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actus_controller/
lib.rs

1//! Public API types and utilities for the Actus controller system — the
2//! `Controller` trait, the typed [`Params`] / [`ExtractedParams`], the route
3//! metadata (`Verb`, `ParamDef`, `RouteDef`), and the route-resolution
4//! [`routing`] helpers. This is what user code and the `#[controller]` /
5//! `routes!` / `app_routes!` macros' generated code interact with.
6#![warn(missing_docs)]
7
8pub use async_trait::async_trait;
9use bytes::Bytes;
10use serde_json::Value as JsonValue;
11use std::any::{Any, TypeId};
12use std::collections::HashMap;
13
14// Re-export the controller macro and app_routes! macro from the macros crate.
15pub use actus_controller_macros::{app_routes, controller};
16pub use actus_reply::prelude::*;
17
18// =========================
19// HTTP Verbs
20// =========================
21
22/// An HTTP method. Used in `routes!` verb prefixes and for the `Allow` header
23/// the framework stamps on `405` responses.
24#[derive(Debug, Clone, Copy, PartialEq, Eq)]
25pub enum Verb {
26    /// The HTTP `GET` method.
27    GET,
28    /// The HTTP `POST` method.
29    POST,
30    /// The HTTP `PUT` method.
31    PUT,
32    /// The HTTP `DELETE` method.
33    DELETE,
34    /// The HTTP `PATCH` method.
35    PATCH,
36    /// The HTTP `HEAD` method.
37    HEAD,
38    /// The HTTP `OPTIONS` method.
39    OPTIONS,
40}
41
42impl Verb {
43    /// The canonical uppercase method token (`"GET"`, `"POST"`, …). Used for
44    /// the `Allow` header on `405` responses, among other things.
45    pub fn as_str(&self) -> &'static str {
46        match self {
47            Verb::GET => "GET",
48            Verb::POST => "POST",
49            Verb::PUT => "PUT",
50            Verb::DELETE => "DELETE",
51            Verb::PATCH => "PATCH",
52            Verb::HEAD => "HEAD",
53            Verb::OPTIONS => "OPTIONS",
54        }
55    }
56}
57
58impl core::fmt::Display for Verb {
59    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
60        f.write_str(self.as_str())
61    }
62}
63
64/// Verbs accepted by a route declared without a verb prefix. Reflects the
65/// "verbs are constraints, not identities" stance: an unmarked route imposes
66/// no semantic restriction beyond what HTML forms emit natively.
67/// Restrictive verbs (PUT/DELETE/PATCH) and protocol verbs (HEAD/OPTIONS)
68/// must be opted into explicitly.
69pub const DEFAULT_VERBS: &[Verb] = &[Verb::GET, Verb::POST];
70
71// =========================
72// Controller mode
73// =========================
74
75/// How a controller treats request parameters it didn't declare.
76#[derive(Debug, Clone, Copy, PartialEq, Eq)]
77pub enum ControllerMode {
78    /// Reject a request that carries parameters the route didn't declare.
79    Strict,
80    /// Allow undeclared extra parameters to pass through.
81    Lax,
82}
83
84// =========================
85// Parameter definitions
86// =========================
87
88/// The declared type of a route parameter — governs how its raw string value
89/// is parsed before reaching the handler.
90#[derive(Debug, Clone, Copy)]
91pub enum ParamType {
92    /// A UTF-8 string.
93    String,
94    /// A signed 64-bit integer (`i64`).
95    Int,
96    /// An unsigned 64-bit integer (`u64`).
97    U64,
98    /// An unsigned 32-bit integer (`u32`).
99    U32,
100    /// A 64-bit float (`f64`).
101    F64,
102    /// A boolean.
103    Bool,
104    /// A repeated parameter collected into `Vec<String>`.
105    StringArray,
106    /// A JSON value (`serde_json::Value`), parsed from the request body.
107    Json,
108    /// The raw request body as `bytes::Bytes`.
109    Bytes,
110}
111
112/// A parameter's default value, applied when the request omits it. Declared
113/// in `routes!` as `name: Type = default`.
114#[derive(Debug, Clone)]
115pub enum ParamDefault {
116    /// `&'static str` (not `String`) so route metadata can live in a
117    /// `static ROUTES: &[RouteDef]` initializer — `String::from(...)` and
118    /// `.to_string()` aren't const on stable Rust. Default-application at
119    /// runtime borrows the str, allocating only if/when needed.
120    String(&'static str),
121    /// A default `i64`.
122    Int(i64),
123    /// A default `u64`.
124    U64(u64),
125    /// A default `u32`.
126    U32(u32),
127    /// A default `f64`.
128    F64(f64),
129    /// A default `bool`.
130    Bool(bool),
131}
132
133/// Where a parameter's value is read from.
134#[derive(Debug, Clone, Copy, PartialEq, Eq)]
135pub enum ParamSource {
136    /// From a `{name}` segment of the URL path.
137    Path,
138    /// From the query string.
139    Query,
140    /// From the request body.
141    Body,
142}
143
144/// The compile-time description of one route parameter, recorded by the
145/// `routes!` macro and used to extract and parse it at request time.
146#[derive(Debug, Clone)]
147pub struct ParamDef {
148    /// The parameter name.
149    pub name: &'static str,
150    /// The declared type the raw value is parsed into.
151    pub ty: ParamType,
152    /// Where the value is read from (path, query, or body).
153    pub source: ParamSource,
154    /// The default applied when the request omits the parameter, if any.
155    pub default: Option<ParamDefault>,
156}
157
158// =========================
159// Route definition
160// =========================
161
162/// The compile-time description of one route in a controller, recorded by the
163/// `routes!` macro. The framework matches and dispatches against these, and
164/// tools can introspect them (e.g. the OpenAPI generator).
165#[derive(Debug, Clone)]
166pub struct RouteDef {
167    /// The route pattern relative to the controller's mount (e.g.
168    /// `"posts/{id}"`).
169    pub pattern: &'static str,
170    /// Internal dispatch token (`"handler_0"`, `"handler_1"`, …) produced by
171    /// the `#[controller]` macro. Opaque to user code; for the
172    /// human-readable handler method name (useful for OpenAPI operationIds
173    /// and the like), see [`RouteDef::handler`].
174    pub handler_id: &'static str,
175    /// Handler method name as written in the controller's `impl` block
176    /// (`"list"`, `"get"`, `"create"`, …). Captured at macro-expansion time
177    /// so introspection tools (OpenAPI doc generators, route audit scripts)
178    /// can identify the handler without grepping.
179    pub handler: &'static str,
180    /// Verbs this route accepts. Always non-empty: a single-element slice for
181    /// an explicitly declared verb, [`DEFAULT_VERBS`] for an unmarked route.
182    pub verb: &'static [Verb],
183    /// The route's declared parameters, in order.
184    pub params: &'static [ParamDef],
185    /// The handler method's `///` doc comment, if any — surfaced to tools like
186    /// the OpenAPI generator.
187    pub doc: Option<&'static str>,
188}
189
190// =========================
191// Runtime parameter handling
192// =========================
193
194/// Raw parameters from the HTTP request, plus headers, the parsed body, and
195/// a typed extensions slot for per-request data that prepare hooks (or
196/// middleware) want to attach for handlers to read.
197///
198/// Headers are a **multimap**, just like query: each lowercased name maps to
199/// every value seen for it, in request order. Scalar accessor
200/// [`Params::header`] reads the first value (the common case);
201/// [`Params::header_all`] returns every value (for `Forwarded`, `Via`, etc.
202/// which can legitimately appear multiple times — e.g. in a proxy chain).
203///
204/// Query parameters are a **multimap**: each name maps to *every* value seen
205/// for it, in request order — `?tags=a&tags=b` is `{"tags": ["a", "b"]}`.
206/// Scalar accessors (`require`, `get_u64`, …) read the first value;
207/// [`Params::get_all`] returns the whole list (this is what backs
208/// `Vec<String>` handler parameters, so a one-element array works the same
209/// as a many-element one). Repeated *keys* are what create multiple values;
210/// a comma in a single value (`?tags=a,b`) is just one value `"a,b"`.
211///
212/// `body` and `raw_body` are populated by the server's `Request::to_params`
213/// using `Content-Type` discrimination:
214///
215/// * `application/json` → `body = Some(parsed)`, `raw_body = original_bytes`.
216/// * `application/x-www-form-urlencoded` → fields are appended into `query`
217///   (same multimap); `body = None`, `raw_body = original_bytes`.
218/// * any other `Content-Type` (including `application/octet-stream`,
219///   `application/zip`, …) → `body = None`, `raw_body = original_bytes`.
220/// * empty body → `body = None`, `raw_body = Bytes::new()`.
221///
222/// A non-empty request body without a `Content-Type` header is rejected
223/// at ingest with `WebError::BadRequest` — `body` and `raw_body` are
224/// therefore never both empty by accident.
225pub struct Params {
226    verb: Verb,
227    query: HashMap<String, Vec<String>>,
228    body: Option<JsonValue>,
229    raw_body: Bytes,
230    headers: HashMap<String, Vec<String>>,
231    extensions: HashMap<TypeId, Box<dyn Any + Send + Sync>>,
232}
233
234impl Params {
235    /// Construct a `Params` from the extracted request pieces. Called by the
236    /// framework's dispatch path; handlers receive an already-built `Params`.
237    pub fn new(
238        verb: Verb,
239        query: HashMap<String, Vec<String>>,
240        body: Option<JsonValue>,
241        raw_body: Bytes,
242        headers: HashMap<String, Vec<String>>,
243    ) -> Self {
244        Self {
245            verb,
246            query,
247            body,
248            raw_body,
249            headers,
250            extensions: HashMap::new(),
251        }
252    }
253
254    /// First value of query parameter `name`, if present. The basis for all
255    /// the scalar accessors below.
256    fn first(&self, name: &str) -> Option<&str> {
257        self.query
258            .get(name)
259            .and_then(|values| values.first())
260            .map(String::as_str)
261    }
262
263    /// The entire query multimap — every parameter name and all its values,
264    /// in request order, plus any folded `application/x-www-form-urlencoded`
265    /// body fields.
266    ///
267    /// Use this for "catch the rest" handlers — a search endpoint with
268    /// open-ended filters, a request proxy, etc.: declare `params: &Params`,
269    /// mark the controller `#[controller(lax)]` so strict mode doesn't reject
270    /// the undeclared keys, and read `params.query()`. Handlers that know
271    /// their parameters up front should declare them as typed arguments
272    /// instead; this is the escape hatch, not the default.
273    pub fn query(&self) -> &HashMap<String, Vec<String>> {
274        &self.query
275    }
276
277    /// Raw bytes of the request body, before any content-type-specific
278    /// parsing. Always present (`Bytes::new()` for empty bodies).
279    ///
280    /// Use this when the handler consumes binary uploads (`.uwx`, image
281    /// blobs, etc.). For JSON bodies, prefer [`Params::json_body`] or
282    /// macro-extracted typed args — those operate on the parsed value
283    /// the framework already produced from the same bytes.
284    pub fn body_bytes(&self) -> &Bytes {
285        &self.raw_body
286    }
287
288    /// Stash a value for later retrieval. The value is keyed by its type;
289    /// inserting a second value of the same type replaces the first.
290    /// Typically called from a `prepare` hook to pass a resolved user (or
291    /// other request-scoped state) through to the handler.
292    pub fn insert<T: Any + Send + Sync>(&mut self, value: T) -> Option<T> {
293        self.extensions
294            .insert(TypeId::of::<T>(), Box::new(value))
295            .and_then(|prev| prev.downcast::<T>().ok().map(|b| *b))
296    }
297
298    /// Look up a value previously inserted with [`Params::insert`].
299    pub fn get<T: Any + Send + Sync>(&self) -> Option<&T> {
300        self.extensions
301            .get(&TypeId::of::<T>())
302            .and_then(|b| b.downcast_ref::<T>())
303    }
304
305    /// The HTTP verb this request was dispatched with.
306    pub fn verb(&self) -> Verb {
307        self.verb
308    }
309
310    /// Look up a request header (case-insensitive). Returns the *first*
311    /// value if the header appears more than once; see [`Params::header_all`]
312    /// for every value.
313    pub fn header(&self, name: &str) -> Option<&str> {
314        self.headers
315            .get(&name.to_ascii_lowercase())
316            .and_then(|values| values.first())
317            .map(String::as_str)
318    }
319
320    /// Every value for a request header (case-insensitive), in receipt
321    /// order. Empty slice if the header wasn't present. Use this for headers
322    /// that can legitimately appear multiple times — `Forwarded`, `Via`,
323    /// `X-Forwarded-For` (when proxies emit one entry per hop), etc.
324    pub fn header_all(&self, name: &str) -> &[String] {
325        self.headers
326            .get(&name.to_ascii_lowercase())
327            .map(Vec::as_slice)
328            .unwrap_or(&[])
329    }
330
331    /// Convenience: extract a Bearer token from the `Authorization` header.
332    /// Returns `None` if the header is missing or doesn't start with `Bearer `.
333    pub fn bearer_token(&self) -> Option<&str> {
334        let auth = self.header("authorization")?;
335        auth.strip_prefix("Bearer ")
336            .or_else(|| auth.strip_prefix("bearer "))
337    }
338
339    // Core methods for parameter extraction
340
341    /// The first value of query parameter `name`, or a `400 Bad Request` if
342    /// it's absent.
343    pub fn require(&self, name: &str) -> Result<&str, WebError> {
344        self.first(name)
345            .ok_or_else(|| WebError::BadRequest(format!("Missing required parameter: {}", name)))
346    }
347
348    /// Look up a query parameter's first value; returns `None` if absent.
349    pub fn get_optional(&self, name: &str) -> Option<&str> {
350        self.first(name)
351    }
352
353    /// Parse query parameter `name` as an `i64`; `400` if missing or unparsable.
354    pub fn get_int(&self, name: &str) -> Result<i64, WebError> {
355        self.require(name)?
356            .parse()
357            .map_err(|_| WebError::BadRequest(format!("Invalid integer: {}", name)))
358    }
359
360    /// Parse optional query parameter `name` as an `i64`; `Ok(None)` if absent,
361    /// `400` if present but unparsable.
362    pub fn get_int_optional(&self, name: &str) -> Result<Option<i64>, WebError> {
363        match self.get_optional(name) {
364            Some(s) => s
365                .parse()
366                .map(Some)
367                .map_err(|_| WebError::BadRequest(format!("Invalid integer: {}", name))),
368            None => Ok(None),
369        }
370    }
371
372    // Extended type methods
373
374    /// Parse query parameter `name` as a `u64`; `400` if missing or unparsable.
375    pub fn get_u64(&self, name: &str) -> Result<u64, WebError> {
376        self.require(name)?
377            .parse()
378            .map_err(|_| WebError::BadRequest(format!("Invalid u64: {}", name)))
379    }
380
381    /// Parse optional query parameter `name` as a `u64`; `Ok(None)` if absent,
382    /// `400` if present but unparsable.
383    pub fn get_u64_optional(&self, name: &str) -> Result<Option<u64>, WebError> {
384        match self.get_optional(name) {
385            Some(s) => s
386                .parse()
387                .map(Some)
388                .map_err(|_| WebError::BadRequest(format!("Invalid u64: {}", name))),
389            None => Ok(None),
390        }
391    }
392
393    /// Parse query parameter `name` as a `u32`; `400` if missing or unparsable.
394    pub fn get_u32(&self, name: &str) -> Result<u32, WebError> {
395        self.require(name)?
396            .parse()
397            .map_err(|_| WebError::BadRequest(format!("Invalid u32: {}", name)))
398    }
399
400    /// Parse optional query parameter `name` as a `u32`; `Ok(None)` if absent,
401    /// `400` if present but unparsable.
402    pub fn get_u32_optional(&self, name: &str) -> Result<Option<u32>, WebError> {
403        match self.get_optional(name) {
404            Some(s) => s
405                .parse()
406                .map(Some)
407                .map_err(|_| WebError::BadRequest(format!("Invalid u32: {}", name))),
408            None => Ok(None),
409        }
410    }
411
412    /// Parse query parameter `name` as an `f64`; `400` if missing or unparsable.
413    pub fn get_f64(&self, name: &str) -> Result<f64, WebError> {
414        self.require(name)?
415            .parse()
416            .map_err(|_| WebError::BadRequest(format!("Invalid float: {}", name)))
417    }
418
419    /// Parse optional query parameter `name` as an `f64`; `Ok(None)` if absent,
420    /// `400` if present but unparsable.
421    pub fn get_f64_optional(&self, name: &str) -> Result<Option<f64>, WebError> {
422        match self.get_optional(name) {
423            Some(s) => s
424                .parse()
425                .map(Some)
426                .map_err(|_| WebError::BadRequest(format!("Invalid float: {}", name))),
427            None => Ok(None),
428        }
429    }
430
431    /// Read query parameter `name` as a bool — `false` when absent, empty,
432    /// `"false"`, or `"0"`; `true` otherwise.
433    pub fn get_bool(&self, name: &str) -> bool {
434        self.first(name)
435            .map(|s| !s.is_empty() && s != "false" && s != "0")
436            .unwrap_or(false)
437    }
438
439    /// Like [`Params::get_bool`], but `None` when the parameter is absent
440    /// (rather than `false`).
441    pub fn get_bool_optional(&self, name: &str) -> Option<bool> {
442        self.first(name)
443            .map(|s| !s.is_empty() && s != "false" && s != "0")
444    }
445
446    /// All values of query parameter `name`, in request order (empty if the
447    /// name wasn't present). Backs `Vec<String>` handler parameters.
448    pub fn get_all(&self, name: &str) -> Result<Vec<String>, WebError> {
449        Ok(self.query.get(name).cloned().unwrap_or_default())
450    }
451
452    /// All values of query parameter `name`; `None` if the name wasn't present
453    /// at all (vs. `Some(vec![])`, which urlencoding can't actually produce).
454    pub fn get_all_optional(&self, name: &str) -> Option<Vec<String>> {
455        self.query.get(name).cloned()
456    }
457
458    /// The parsed JSON request body, or `400 Bad Request` if there wasn't one.
459    pub fn json_body(&self) -> Result<JsonValue, WebError> {
460        self.body
461            .clone()
462            .ok_or_else(|| WebError::BadRequest("Missing JSON body".to_string()))
463    }
464
465    /// In strict mode, return any query keys *not* in `expected` (so the caller
466    /// can reject the request); `None` if every key was expected.
467    pub fn check_unexpected(&self, expected: &[&str]) -> Option<Vec<String>> {
468        let unexpected: Vec<String> = self
469            .query
470            .keys()
471            .filter(|k| !expected.contains(&k.as_str()))
472            .cloned()
473            .collect();
474
475        if unexpected.is_empty() {
476            None
477        } else {
478            Some(unexpected)
479        }
480    }
481}
482
483// =========================
484// Extracted parameters (after route resolution)
485// =========================
486
487/// Parameters extracted after route resolution — path captures plus the
488/// declared query and body values. The `#[controller]` macro reads typed
489/// handler arguments out of this; application code rarely touches it directly.
490#[derive(Debug)]
491pub struct ExtractedParams {
492    /// Path captures (single-segment `{name}` or the joined `{...rest}`).
493    path: HashMap<String, String>,
494    /// Declared query parameters that were present, with *all* their values
495    /// (see [`Params`] — query is a multimap).
496    query: HashMap<String, Vec<String>>,
497    body: Option<JsonValue>,
498    raw_body: Bytes,
499}
500
501impl ExtractedParams {
502    /// The single scalar value for `name`: a path capture takes precedence,
503    /// otherwise the first query value. `None` if neither has it.
504    fn scalar(&self, name: &str) -> Option<&str> {
505        self.path.get(name).map(String::as_str).or_else(|| {
506            self.query
507                .get(name)
508                .and_then(|values| values.first())
509                .map(String::as_str)
510        })
511    }
512
513    fn require_scalar(&self, name: &str) -> Result<&str, WebError> {
514        self.scalar(name)
515            .ok_or_else(|| WebError::BadRequest(format!("Missing parameter: {}", name)))
516    }
517
518    /// The value of path/query parameter `name` as a `String`; `400` if absent.
519    pub fn get_string(&self, name: &str) -> Result<String, WebError> {
520        self.require_scalar(name).map(str::to_string)
521    }
522
523    /// Parse path/query parameter `name` as an `i64`; `400` if missing or
524    /// unparsable.
525    pub fn get_i64(&self, name: &str) -> Result<i64, WebError> {
526        self.require_scalar(name)?
527            .parse()
528            .map_err(|_| WebError::BadRequest(format!("Invalid integer: {}", name)))
529    }
530
531    /// Parse path/query parameter `name` as a `u64`; `400` if missing or
532    /// unparsable.
533    pub fn get_u64(&self, name: &str) -> Result<u64, WebError> {
534        self.require_scalar(name)?
535            .parse()
536            .map_err(|_| WebError::BadRequest(format!("Invalid u64: {}", name)))
537    }
538
539    /// Parse path/query parameter `name` as a `u32`; `400` if missing or
540    /// unparsable.
541    pub fn get_u32(&self, name: &str) -> Result<u32, WebError> {
542        self.require_scalar(name)?
543            .parse()
544            .map_err(|_| WebError::BadRequest(format!("Invalid u32: {}", name)))
545    }
546
547    /// Parse path/query parameter `name` as an `f64`; `400` if missing or
548    /// unparsable.
549    pub fn get_f64(&self, name: &str) -> Result<f64, WebError> {
550        self.require_scalar(name)?
551            .parse()
552            .map_err(|_| WebError::BadRequest(format!("Invalid float: {}", name)))
553    }
554
555    /// Read path/query parameter `name` as a bool — `false` for an empty value,
556    /// `"false"` or `"0"`; `true` otherwise. **`400` when absent**, exactly as
557    /// `get_string` / `get_i64` / every other scalar getter, all of which go
558    /// through `require_scalar`.
559    ///
560    /// ⛔ **It did NOT always do that**, and the history is the point. It used to
561    /// answer `Ok(false)` for a missing parameter — the one getter that invented
562    /// a value instead of erroring. The generated default is
563    /// `get_x(name).unwrap_or(default)`, which relies on that `Err`, so this
564    /// method swallowed the absence and **every `param: bool = true` silently
565    /// behaved as `false`**.
566    ///
567    /// ⚠️ Found in a consumer, 2026-09-04: a cancellation route declared
568    /// `at_period_end: bool = true` and documented the reversible, deferred form as
569    /// its default. A client that omitted the parameter got the **immediate**
570    /// cancellation instead — the destructive direction, and the opposite of what
571    /// the route promised. It stayed invisible because the route behaved correctly
572    /// whenever the parameter **was** supplied.
573    ///
574    /// ⇒ Use [`Self::get_bool_optional`] when you need to tell an absent
575    /// parameter from an explicit `false`; that is what a declared default reads.
576    ///
577    /// ⚠️ **Correction, 2026-09-04.** This doc used to justify the old
578    /// `unwrap_or(false)` by saying a bare `param: bool` means *"false unless
579    /// asked for"* (`confirm`, `dry_run`) and that erroring on absence would turn
580    /// those into `400`s. **That was false and was never checked**: a bare `bool`
581    /// *already* 400s, because [`routing::param_is_required`] reports it required
582    /// and `resolve` rejects the request before extraction runs. An optional flag
583    /// is written `confirm: bool = false`. The fallback was the last code in the
584    /// crate asserting the opposite of what the router does, so it is gone —
585    /// nothing outside this crate could reach it, since [`ExtractedParams`] has
586    /// no public constructor and `resolve` is the only way to obtain one.
587    pub fn get_bool(&self, name: &str) -> Result<bool, WebError> {
588        Ok(!matches!(self.require_scalar(name)?, "" | "false" | "0"))
589    }
590
591    /// Like [`Self::get_bool`], but distinguishes **absent** (`None`) from the
592    /// value `false` — the reader a declared default needs.
593    ///
594    /// ⭐ This exists because `bool` is the only parameter type where "not
595    /// supplied" and "supplied as the falsy value" are both meaningful. For every
596    /// other type the absence is already an `Err` and the default falls out of
597    /// `unwrap_or`; here it has to be asked for explicitly.
598    ///
599    /// The `_optional` name is the crate's convention for exactly this pair —
600    /// see [`Params::get_bool_optional`], which draws the same distinction on
601    /// the pre-resolution type. (This one returns `Result` because every
602    /// `ExtractedParams` getter does; it has no failure case of its own.)
603    pub fn get_bool_optional(&self, name: &str) -> Result<Option<bool>, WebError> {
604        Ok(self
605            .scalar(name)
606            .map(|s| !s.is_empty() && s != "false" && s != "0"))
607    }
608
609    /// All values for `name` (in request order; empty if the name wasn't
610    /// present). Backs `Vec<String>` handler parameters — a one-element list
611    /// (`?tags=a`) and a many-element one (`?tags=a&tags=b`) flow through the
612    /// same path.
613    pub fn get_string_array(&self, name: &str) -> Result<Vec<String>, WebError> {
614        Ok(self.query.get(name).cloned().unwrap_or_default())
615    }
616
617    /// The parsed JSON request body, or `400 Bad Request` if there wasn't one.
618    pub fn get_json_body(&self) -> Result<JsonValue, WebError> {
619        self.body
620            .clone()
621            .ok_or_else(|| WebError::BadRequest("Missing JSON body".to_string()))
622    }
623
624    /// Raw bytes of the request body. See [`Params::body_bytes`] for the
625    /// content-type-aware semantics. Used by the macro to extract a
626    /// `Bytes` handler argument.
627    pub fn get_body_bytes(&self) -> Bytes {
628        self.raw_body.clone()
629    }
630}
631
632// =========================
633// Routing utilities module
634// =========================
635
636/// Route resolution helpers — matching a request path + verb against a
637/// controller's `&[RouteDef]` and extracting the path/query/body parameters.
638/// Used by the `#[controller]` macro's generated dispatch; exposed for tools
639/// and tests that need to resolve routes directly.
640pub mod routing {
641    use super::*;
642    use std::collections::HashMap;
643
644    /// The segments of a mount path or family prefix, normalised exactly as
645    /// `RouterBuilder::add_route` and the `families` block of `app_routes!`
646    /// normalise them: surrounding slashes trimmed, empty segments dropped, a
647    /// trailing `*` (the catch-all sugar) removed — so `"api/*"`, `"/api/"`
648    /// and `"api"` are the same prefix, and `""` / `"*"` is the root.
649    pub fn family_segments(path: &str) -> Vec<&str> {
650        let mut segs: Vec<&str> = path
651            .trim_matches('/')
652            .split('/')
653            .filter(|s| !s.is_empty())
654            .collect();
655        if segs.last() == Some(&"*") {
656            segs.pop();
657        }
658        segs
659    }
660
661    /// Which of `prefixes` covers `mount` — by the **same rule the `families`
662    /// block of `app_routes!` applies at compile time**, so a boot-time check
663    /// written against this cannot disagree with the compile-time one:
664    /// segment-aligned (`"api"` covers `"api/things"`, never `"apiary"`), the
665    /// **longest** covering prefix wins (so `"api/auth"` carves its subtree out
666    /// of `"api"`), a trailing `*` reads as the prefix before it, and the root
667    /// (`""` or `"*"`) covers every mount. Returns the winning prefix as it was
668    /// given, so the caller can look it up in its own table. On two prefixes
669    /// that normalise identically, the later one wins, as in the macro.
670    ///
671    /// Do not re-derive this with `mount.split('/').next()`: that matches by
672    /// first segment, agrees with the macro only while every family is a single
673    /// segment, and silently diverges the moment one nests.
674    pub fn covering_family<'a, I>(mount: &str, prefixes: I) -> Option<&'a str>
675    where
676        I: IntoIterator<Item = &'a str>,
677    {
678        let m = family_segments(mount);
679        let mut best: Option<(&'a str, usize)> = None;
680        for p in prefixes {
681            let ps = family_segments(p);
682            let covers = ps.len() <= m.len() && ps.iter().zip(m.iter()).all(|(a, b)| a == b);
683            if covers && best.is_none_or(|(_, n)| ps.len() >= n) {
684                best = Some((p, ps.len()));
685            }
686        }
687        best.map(|(p, _)| p)
688    }
689
690    /// Whether an absent value for `param` makes the request a `400`.
691    ///
692    /// ⭐ **This is the rule [`resolve`] enforces, exported so that a tool
693    /// reporting requiredness cannot disagree with the router that enforces it.**
694    /// The OpenAPI generator's `required` flag is computed from this; before it
695    /// was extracted the same expression was written out in two crates with
696    /// nothing relating them, and they agreed only by diligence.
697    ///
698    /// The rule is **syntactic, and uniform across every scalar type**: a query
699    /// parameter is required unless it declared a default. Requiredness is
700    /// therefore readable straight off a `routes!` block — `name: T` is required,
701    /// `name: T = x` is optional — without knowing what `T` is.
702    ///
703    /// ⛔ **`bool` is deliberately NOT exempt**, though the pull to exempt it is
704    /// strong: `confirm: bool` is required, and an optional flag must be written
705    /// `confirm: bool = false`. Two reasons. It keeps *both* meanings sayable —
706    /// exempting `bool` would leave no way to declare a required one. And an
707    /// absent `bool` and an explicit `?flag=false` are genuinely distinguishable
708    /// on the wire (see [`ExtractedParams::get_bool_optional`]), so reading
709    /// absence as `false` would discard a distinction the request carries.
710    ///
711    /// [`ParamType::StringArray`] is exempt for the opposite reason — its
712    /// exemption is **forced, not chosen**: urlencoding cannot express "present
713    /// but empty" (see [`Params::get_all_optional`]), so there is no
714    /// required/optional distinction available to lose. ⇒ A new type earns an
715    /// exemption only when the wire format denies it the distinction. That it
716    /// merely *has* a natural zero value is not enough.
717    pub fn param_is_required(param: &ParamDef) -> bool {
718        match param.source {
719            // A `{name}` capture is always present when the pattern matched, so
720            // absence never arises. (OpenAPI additionally *mandates*
721            // `required: true` for path parameters.)
722            ParamSource::Path => true,
723            // The body is required by whichever getter reads it.
724            ParamSource::Body => true,
725            // The only case that actually varies.
726            ParamSource::Query => {
727                param.default.is_none() && !matches!(param.ty, ParamType::StringArray)
728            }
729        }
730    }
731
732    /// Main route resolution function. Tries each route in declaration order
733    /// and returns the first whose path pattern *and* verb both match, along
734    /// with its extracted parameters.
735    ///
736    /// "Declaration order" matters: when two patterns can match the same
737    /// action (e.g. `"special"` and `"{id}"`), the one declared first wins —
738    /// list the more specific route earlier.
739    ///
740    /// When no route fully matches, the error distinguishes:
741    /// - `WebError::MethodNotAllowed(methods)`: at least one route's *path*
742    ///   pattern matched but its verb didn't; `methods` is the (sorted, deduped)
743    ///   set of verbs those routes accept, which the caller surfaces as the
744    ///   `Allow` header.
745    /// - `WebError::NotFound`: no route's path pattern matched at all.
746    #[inline]
747    pub fn resolve<'a>(
748        routes: &'a [RouteDef],
749        action: &str,
750        params: &Params,
751        mode: ControllerMode,
752    ) -> Result<(&'a RouteDef, ExtractedParams), WebError> {
753        // Verbs accepted by routes whose *path* matched but whose verb didn't.
754        let mut allowed_methods: Vec<&'static str> = Vec::new();
755
756        for route in routes {
757            // Pattern match first.
758            let path_params = match match_pattern(route.pattern, action) {
759                Some(p) => p,
760                None => continue,
761            };
762
763            // Then verb check. `route.verb` is the (non-empty) set of verbs
764            // this route accepts; an unmarked route carries `DEFAULT_VERBS`.
765            if !route.verb.contains(&params.verb()) {
766                for v in route.verb {
767                    let token = v.as_str();
768                    if !allowed_methods.contains(&token) {
769                        allowed_methods.push(token);
770                    }
771                }
772                continue;
773            }
774
775            // Full match: build extracted params and return.
776            {
777                // Build extracted params
778                let mut extracted = ExtractedParams {
779                    path: path_params,
780                    query: HashMap::new(),
781                    body: params.body.clone(),
782                    raw_body: params.raw_body.clone(),
783                };
784
785                // Extract and validate parameters
786                for param_def in route.params {
787                    match param_def.source {
788                        ParamSource::Path => {
789                            // Path-source params come from `{name}` / `{...name}`
790                            // tokens, which `match_pattern` always captures when
791                            // the pattern matched — so this is already in
792                            // `extracted.path`. (The `#[controller]` macro is what
793                            // guarantees the `ParamDef` ↔ pattern correspondence;
794                            // a hand-built `RouteDef` that violates it would trip
795                            // this in debug builds.)
796                            debug_assert!(
797                                extracted.path.contains_key(param_def.name),
798                                "path parameter `{}` not captured by pattern",
799                                param_def.name
800                            );
801                        }
802                        ParamSource::Query => {
803                            // Requiredness is `param_is_required` and nothing
804                            // else — the OpenAPI generator reports the same
805                            // predicate, so a spec cannot claim a parameter is
806                            // optional that this branch would 400.
807                            if let Some(value) = params.query.get(param_def.name) {
808                                extracted
809                                    .query
810                                    .insert(param_def.name.to_string(), value.clone());
811                            } else if param_is_required(param_def) {
812                                return Err(WebError::BadRequest(format!(
813                                    "Missing required parameter: {}",
814                                    param_def.name
815                                )));
816                            }
817                            // Defaults are applied in the handler extraction phase.
818                        }
819                        ParamSource::Body => {
820                            // JSON body is already handled
821                        }
822                    }
823                }
824
825                // Check for unexpected parameters in strict mode
826                if mode == ControllerMode::Strict {
827                    let expected: Vec<&str> = route
828                        .params
829                        .iter()
830                        .filter(|p| p.source == ParamSource::Query)
831                        .map(|p| p.name)
832                        .collect();
833
834                    if let Some(unexpected) = params.check_unexpected(&expected) {
835                        return Err(WebError::BadRequest(format!(
836                            "Unexpected parameters: {}",
837                            unexpected.join(", ")
838                        )));
839                    }
840                }
841
842                return Ok((route, extracted));
843            }
844        }
845
846        if allowed_methods.is_empty() {
847            Err(WebError::NotFound)
848        } else {
849            allowed_methods.sort_unstable();
850            allowed_methods.dedup();
851            Err(WebError::MethodNotAllowed(allowed_methods))
852        }
853    }
854
855    /// If `segment` is a `{...name}` rest token, returns `name` (non-empty).
856    fn rest_token_name(segment: &str) -> Option<&str> {
857        segment
858            .strip_prefix("{...")
859            .and_then(|s| s.strip_suffix('}'))
860            .filter(|name| !name.is_empty())
861    }
862
863    /// Match one fixed (non-rest) pattern segment against a path segment,
864    /// recording a capture for `{name}` tokens. Returns `false` if a literal
865    /// segment doesn't match.
866    fn match_fixed_segment(
867        pattern_part: &str,
868        path_part: &str,
869        params: &mut HashMap<String, String>,
870    ) -> bool {
871        if let Some(param_name) = pattern_part
872            .strip_prefix('{')
873            .and_then(|s| s.strip_suffix('}'))
874        {
875            params.insert(param_name.to_string(), path_part.to_string());
876            true
877        } else {
878            pattern_part == path_part
879        }
880    }
881
882    /// Split a pattern or action into its segments. A pattern/action is a
883    /// `/`-joined list of **non-empty** segments; empty segments — from
884    /// leading, trailing, or doubled slashes, and notably from the empty
885    /// action `""` (which `str::split` would otherwise yield as `[""]`) —
886    /// are not segments. This is the same normalization `Request` applies to
887    /// the full request path, applied here to the per-controller action and
888    /// the route patterns it's matched against.
889    fn segments(s: &str) -> Vec<&str> {
890        s.split('/').filter(|seg| !seg.is_empty()).collect()
891    }
892
893    /// Match a route pattern against an action path.
894    /// Returns extracted path parameters if matched.
895    ///
896    /// Both sides are viewed as lists of non-empty path segments.
897    /// A literal segment or `{name}` token is **required** — it has no match
898    /// when there's no segment to fill it, so `match_pattern("{id}", "")` is
899    /// `None`. (A controller that wants to serve its collection root declares
900    /// `"" => …`.)
901    ///
902    /// A trailing `{...name}` token is a *rest* parameter: it captures the
903    /// remainder of the path (slashes included) and matches **zero or more**
904    /// segments — `match_pattern("{...path}", "")` is `Some({path: ""})`, and
905    /// `"{folder_id}/{...path}"` matches `"abc"` (`path == ""`) and
906    /// `"abc/x/y"` (`path == "x/y"`) but **not** `""` (the required
907    /// `folder_id` has no segment). The `#[controller]` macro enforces that
908    /// `{...name}` appears at most once and only as the final token; this
909    /// function trusts that and only inspects the last token.
910    #[inline]
911    pub fn match_pattern(pattern: &str, path: &str) -> Option<HashMap<String, String>> {
912        let pattern_parts = segments(pattern);
913        let path_parts = segments(path);
914        let mut params = HashMap::new();
915
916        if let Some(rest_name) = pattern_parts.last().and_then(|s| rest_token_name(s)) {
917            // Everything before the rest token is a fixed prefix that must
918            // match segment-for-segment; the rest token soaks up whatever
919            // is left (possibly nothing).
920            let fixed = &pattern_parts[..pattern_parts.len() - 1];
921            if path_parts.len() < fixed.len() {
922                return None;
923            }
924            for (pattern_part, path_part) in fixed.iter().zip(path_parts.iter()) {
925                if !match_fixed_segment(pattern_part, path_part, &mut params) {
926                    return None;
927                }
928            }
929            params.insert(rest_name.to_string(), path_parts[fixed.len()..].join("/"));
930            return Some(params);
931        }
932
933        if pattern_parts.len() != path_parts.len() {
934            return None;
935        }
936        for (pattern_part, path_part) in pattern_parts.iter().zip(path_parts.iter()) {
937            if !match_fixed_segment(pattern_part, path_part, &mut params) {
938                return None;
939            }
940        }
941        Some(params)
942    }
943}
944
945// =========================
946// Controller trait
947// =========================
948
949/// The runtime interface every controller implements. Hand-writing this is
950/// possible but unusual — the `#[controller]` macro generates the
951/// implementation (dispatch table, parameter extraction, the metadata methods)
952/// from a controller's `impl` block and its `routes!` declaration.
953#[async_trait]
954pub trait Controller: Send + Sync {
955    /// Route `action` (the path below this controller's mount) to the matching
956    /// handler and run it, returning its [`Reply`]. Generated by the macro.
957    async fn actus_dispatch(&self, action: &str, params: Params) -> Reply;
958
959    /// The controller's type name, for diagnostics and route auditing.
960    fn __name(&self) -> &'static str;
961
962    /// The controller's declared routes, for introspection (OpenAPI
963    /// generation, route audits). Defaults to empty; the macro overrides it.
964    fn actus_describe_routes(&self) -> Vec<RouteDef> {
965        vec![]
966    }
967
968    /// Per-controller maximum buffered body size, in bytes. Returned by the
969    /// `#[controller(max_body_bytes = …)]` attribute when set; `None` means the
970    /// controller defers to the server-level cap (`Server::with_max_body_bytes`).
971    ///
972    /// Resolution at request time (see `Server::handle_request_inner`):
973    /// controller value if `Some`, otherwise the server-wide cap, otherwise
974    /// `DEFAULT_MAX_BODY_BYTES` (2 MiB).
975    ///
976    /// The framework calls this *before* buffering the body — so a 1 KB
977    /// controller cap rejects a 50 KB request before the bytes are
978    /// allocated. (A request body big enough to be a memory concern
979    /// shouldn't get past the framework regardless of where the handler
980    /// would have rejected it.)
981    fn actus_max_body_bytes(&self) -> Option<usize> {
982        None
983    }
984
985    /// Per-controller rate-limit *class* label, as declared by
986    /// `#[controller(rate_limit = "name")]`. `None` (the default) means the
987    /// controller declared no class.
988    ///
989    /// This is a **label, not a policy**. Actus is policy-agnostic: it ships
990    /// no limiter algorithm, key function, or store, because the framework
991    /// can't pick those correctly for someone else (which key — IP / user /
992    /// API key? which algorithm — token bucket / sliding window? which store
993    /// — in-memory / Redis?). Those are application decisions, so the limiter
994    /// itself stays an application `Middleware`.
995    ///
996    /// What the framework *does* own is auditability and the response shape.
997    /// The server stamps this label onto the matched request (surfaced as
998    /// `Request::rate_limit_class` in `actus-server`), so a reviewer can read
999    /// each endpoint's rate-limit class straight off the `#[controller(...)]`
1000    /// line, and an application's rate-limit `Middleware` can map class →
1001    /// policy and reject over-limit requests with
1002    /// [`WebError::TooManyRequests`] (429 + `Retry-After`, also framework-owned).
1003    /// Two controllers sharing a class share a limit namespace; what each
1004    /// class *means* is the application's call.
1005    ///
1006    /// Resolution is per-controller, mirroring [`Controller::actus_max_body_bytes`].
1007    /// A per-route override would be an additive future change (the same shape
1008    /// as the per-route body-cap proposal).
1009    fn actus_rate_limit(&self) -> Option<&'static str> {
1010        None
1011    }
1012
1013    /// The controller's declared caller expectation, as set by
1014    /// `#[controller(expects = "…")]`. `None` (the default) means the
1015    /// controller declared nothing.
1016    ///
1017    /// This is a **label, not a policy** — and specifically a **floor**: it
1018    /// names the *least-privileged caller the controller is written to
1019    /// accept* (`"credential"`, `"anonymous"`, `"signature"`, …). It is not a
1020    /// ceiling — individual routes may demand more in their handlers — and it
1021    /// is not authorization: Actus never interprets the value, compares it
1022    /// only for presence/equality in application code, and hands it back
1023    /// untouched. What each label *means*, and what happens to a caller below
1024    /// the floor, is entirely the application's (typically: a startup
1025    /// coverage check over [`Router::mounts`], a declaration-keyed gate in a
1026    /// `prepare` hook or middleware, and a probe test — see the README's
1027    /// "Route families" section).
1028    ///
1029    /// Resolution is per-controller, mirroring
1030    /// [`Controller::actus_rate_limit`]. A controller with routes above its
1031    /// floor declares the floor and enforces the stricter routes in their
1032    /// handlers.
1033    ///
1034    /// [`Router::mounts`]: https://docs.rs/actus-server/latest/actus_server/struct.Router.html#method.mounts
1035    fn actus_expects(&self) -> Option<&'static str> {
1036        None
1037    }
1038
1039    /// The path of the controller's `prepare` hook, as written in
1040    /// `#[controller(prepare = …)]` (e.g. `"Self::auth"`), or `None` when the
1041    /// controller declared no hook.
1042    ///
1043    /// **Presence is the payload.** A route-family coverage check reads this
1044    /// to enforce rules like *"a controller whose floor is `"credential"`
1045    /// must have a hook to refuse anonymous callers with"* — the string
1046    /// itself is a courtesy for route dumps and diagnostics, not an
1047    /// invocation handle.
1048    fn actus_prepare(&self) -> Option<&'static str> {
1049        None
1050    }
1051}
1052
1053// =========================
1054// Route families — the compile-time half (Phase 2)
1055// =========================
1056
1057/// Implemented by the `#[controller]` macro for every controller that declares
1058/// `expects = "…"`; **absent on a controller that declares nothing**, which is
1059/// the whole point. The `families { … }` block in `app_routes!` requires this
1060/// trait of every controller mounted under a listed prefix, so a silently
1061/// undeclared controller under a covered prefix is a **compile error** — the
1062/// `on_unimplemented` message below is the one the developer reads.
1063///
1064/// `EXPECTS` is the same label [`Controller::actus_expects`] returns at runtime,
1065/// lifted to a constant so a family's *accepted set* can be checked at compile
1066/// time too (see [`declares_expectation_in`]).
1067#[diagnostic::on_unimplemented(
1068    message = "`{Self}` is mounted under a route family that requires a declared caller expectation",
1069    label = "this controller declares no `expects` label",
1070    note = "add `expects = \"…\"` to its `#[controller(...)]` attribute, or drop the prefix \
1071            from the `families` block in `app_routes!`"
1072)]
1073pub trait DeclaresExpectation {
1074    /// The declared floor — the value of `#[controller(expects = …)]`.
1075    const EXPECTS: &'static str;
1076}
1077
1078/// A route family's accepted floors, as a type — generated by `app_routes!` for
1079/// each `"prefix" => ["floor", …]` entry in its `families` block, and handed to
1080/// [`declares_expectation_in`] so the acceptance check can run in a `const`.
1081pub trait Family {
1082    /// The floors this family accepts.
1083    const ACCEPTS: &'static [&'static str];
1084}
1085
1086/// `const`-evaluable string equality (`==` on `str` is not `const`).
1087pub const fn str_eq(a: &str, b: &str) -> bool {
1088    let (a, b) = (a.as_bytes(), b.as_bytes());
1089    if a.len() != b.len() {
1090        return false;
1091    }
1092    let mut i = 0;
1093    while i < a.len() {
1094        if a[i] != b[i] {
1095            return false;
1096        }
1097        i += 1;
1098    }
1099    true
1100}
1101
1102/// `const`-evaluable "is `floor` one of `accepts`".
1103pub const fn floor_accepted(floor: &str, accepts: &[&str]) -> bool {
1104    let mut i = 0;
1105    while i < accepts.len() {
1106        if str_eq(floor, accepts[i]) {
1107            return true;
1108        }
1109        i += 1;
1110    }
1111    false
1112}
1113
1114/// Identity pass-through that only compiles for a controller implementing
1115/// [`DeclaresExpectation`]. `app_routes!` wraps a mount's construction
1116/// expression in this when the mount falls under a `families` prefix declared
1117/// without an accepted set — so *presence* of a declaration is checked at
1118/// compile time, and any construction form (`Foo { db }`, `Foo::new(db)`,
1119/// `make_foo()`) works without the macro naming the type.
1120#[inline(always)]
1121pub fn declares_expectation<T: Controller + DeclaresExpectation>(c: T) -> T {
1122    c
1123}
1124
1125/// [`declares_expectation`], plus the *value* check: the controller's
1126/// [`DeclaresExpectation::EXPECTS`] must be one of `F::ACCEPTS`. The check is a
1127/// `const` assertion evaluated when this instantiation is compiled — i.e. when
1128/// the generated `init()` is reachable from something that runs, which in an
1129/// application it always is. A failure reads as an `E0080` naming the
1130/// controller type in its "while instantiating" note. ⚠️ Evaluation needs
1131/// codegen: `cargo check` (and IDE diagnostics built on it) does not run it;
1132/// `cargo build`, `cargo test` and CI do — only the presence bound is a type
1133/// error visible under `check`. (The boot-time coverage check over
1134/// `Router::mounts()` remains the backstop that needs no reachability.)
1135#[inline(always)]
1136pub fn declares_expectation_in<F: Family, T: Controller + DeclaresExpectation>(c: T) -> T {
1137    const {
1138        assert!(
1139            floor_accepted(T::EXPECTS, F::ACCEPTS),
1140            "this controller declares a caller expectation (`expects = …`) that its route \
1141             family does not accept — see the `families` block in `app_routes!`"
1142        )
1143    };
1144    c
1145}
1146
1147/// A list of `(mount, controller-factory)` pairs — the route-registration
1148/// shape the `app_routes!` macro builds when wiring controllers into a router.
1149pub type Routes = Vec<(
1150    &'static str,
1151    Box<dyn Fn() -> Box<dyn Controller> + Send + Sync>,
1152)>;
1153
1154/// A marker macro to define routes within a `#[controller]` impl block.
1155/// The `#[controller]` procedural macro is responsible for parsing this.
1156#[macro_export]
1157macro_rules! routes {
1158    ($($tokens:tt)*) => {};
1159}
1160
1161#[cfg(test)]
1162mod match_pattern_tests {
1163    use super::routing::match_pattern;
1164
1165    fn cap(pattern: &str, path: &str) -> Option<Vec<(String, String)>> {
1166        match_pattern(pattern, path).map(|m| {
1167            let mut v: Vec<_> = m.into_iter().collect();
1168            v.sort();
1169            v
1170        })
1171    }
1172
1173    fn pair(k: &str, v: &str) -> (String, String) {
1174        (k.to_string(), v.to_string())
1175    }
1176
1177    #[test]
1178    fn fixed_patterns_still_work() {
1179        assert_eq!(cap("", ""), Some(vec![]));
1180        assert_eq!(cap("{id}", "42"), Some(vec![pair("id", "42")]));
1181        assert_eq!(
1182            cap("posts/{id}/comments", "posts/3/comments"),
1183            Some(vec![pair("id", "3")])
1184        );
1185        assert_eq!(cap("a/b", "a/b/c"), None);
1186        assert_eq!(cap("a/b/c", "a/b"), None);
1187        assert_eq!(cap("posts/{id}", "users/3"), None);
1188    }
1189
1190    #[test]
1191    fn required_segments_dont_match_the_empty_action() {
1192        // A `{id}` (or any literal) is required: it has no match when there's
1193        // no segment for it. The empty action is the empty segment list, not
1194        // a one-element list containing `""`.
1195        assert_eq!(cap("{id}", ""), None);
1196        assert_eq!(cap("posts", ""), None);
1197        assert_eq!(cap("{a}/{b}", "x"), None);
1198        // ...but the empty pattern is *defined* as the empty segment list,
1199        // so it matches the empty action (this is how `"" => index` works).
1200        assert_eq!(cap("", ""), Some(vec![]));
1201        assert_eq!(cap("", "x"), None);
1202    }
1203
1204    #[test]
1205    fn rest_param_captures_remainder() {
1206        assert_eq!(
1207            cap("{folder_id}/{...path}", "abc/x/y/z"),
1208            Some(vec![pair("folder_id", "abc"), pair("path", "x/y/z")])
1209        );
1210        // zero trailing segments → rest is empty (folder_id is still present)
1211        assert_eq!(
1212            cap("{folder_id}/{...path}", "abc"),
1213            Some(vec![pair("folder_id", "abc"), pair("path", "")])
1214        );
1215        // ...but the required folder_id has no segment in the empty action
1216        assert_eq!(cap("{folder_id}/{...path}", ""), None);
1217    }
1218
1219    #[test]
1220    fn rest_param_as_sole_token() {
1221        assert_eq!(cap("{...path}", "a/b/c"), Some(vec![pair("path", "a/b/c")]));
1222        assert_eq!(cap("{...path}", "a"), Some(vec![pair("path", "a")]));
1223        // a sole rest token explicitly matches zero segments
1224        assert_eq!(cap("{...path}", ""), Some(vec![pair("path", "")]));
1225    }
1226
1227    #[test]
1228    fn rest_param_after_literal_prefix() {
1229        assert_eq!(
1230            cap("files/{...path}", "files/x/y"),
1231            Some(vec![pair("path", "x/y")])
1232        );
1233        assert_eq!(
1234            cap("files/{...path}", "files"),
1235            Some(vec![pair("path", "")])
1236        );
1237        assert_eq!(cap("files/{...path}", "other/x"), None);
1238        // a literal prefix longer than the path can't match
1239        assert_eq!(cap("a/b/{...path}", "a"), None);
1240    }
1241}
1242
1243#[cfg(test)]
1244mod resolve_tests {
1245    use super::routing::resolve;
1246    use super::*;
1247    use bytes::Bytes;
1248    use std::collections::HashMap;
1249
1250    fn params_with(verb: Verb, query: HashMap<String, Vec<String>>) -> Params {
1251        Params::new(verb, query, None, Bytes::new(), HashMap::new())
1252    }
1253
1254    #[test]
1255    fn headers_are_a_multimap_first_value_wins_for_scalar_access() {
1256        // Two values for one header name (e.g. a proxy chain stamping
1257        // `Forwarded` twice). `header()` returns the first; `header_all()`
1258        // returns both, in receipt order. Absent headers come back as `None`
1259        // / empty slice respectively.
1260        let mut headers = HashMap::new();
1261        headers.insert(
1262            "forwarded".to_string(),
1263            vec!["for=1.2.3.4".to_string(), "for=10.0.0.1".to_string()],
1264        );
1265        headers.insert("x-trace-id".to_string(), vec!["abc-123".to_string()]);
1266        let p = Params::new(Verb::GET, HashMap::new(), None, Bytes::new(), headers);
1267
1268        // Case-insensitive lookup; first value for scalar access.
1269        assert_eq!(p.header("Forwarded"), Some("for=1.2.3.4"));
1270        assert_eq!(p.header("FORWARDED"), Some("for=1.2.3.4"));
1271        assert_eq!(p.header_all("Forwarded"), ["for=1.2.3.4", "for=10.0.0.1"]);
1272
1273        // Single-value headers still work — header_all yields a one-element
1274        // slice, header yields the same value.
1275        assert_eq!(p.header("X-Trace-Id"), Some("abc-123"));
1276        assert_eq!(p.header_all("X-Trace-Id"), ["abc-123"]);
1277
1278        // Absent: None / empty slice.
1279        assert_eq!(p.header("Authorization"), None);
1280        assert!(p.header_all("Authorization").is_empty());
1281    }
1282
1283    #[test]
1284    fn params_query_exposes_the_whole_multimap() {
1285        let mut q = HashMap::new();
1286        q.insert("a".to_string(), vec!["1".to_string(), "2".to_string()]);
1287        q.insert("b".to_string(), vec!["3".to_string()]);
1288        let p = params_with(Verb::GET, q);
1289        assert_eq!(p.query().len(), 2);
1290        assert_eq!(
1291            p.query().get("a").unwrap(),
1292            &["1".to_string(), "2".to_string()]
1293        );
1294        // scalar view still takes the first
1295        assert_eq!(p.get_optional("a"), Some("1"));
1296    }
1297
1298    #[test]
1299    fn verb_mismatch_yields_405_with_sorted_deduped_allow_list() {
1300        // `""` matches the action `""` for both routes; the request verb
1301        // (PUT) matches neither, so we get 405 carrying the union of their
1302        // verbs — sorted and deduped, so the `Allow` header is deterministic.
1303        static ROUTES: &[RouteDef] = &[
1304            RouteDef {
1305                pattern: "",
1306                handler_id: "create",
1307                handler: "create",
1308                verb: &[Verb::POST],
1309                params: &[],
1310                doc: None,
1311            },
1312            RouteDef {
1313                pattern: "",
1314                handler_id: "list",
1315                handler: "list",
1316                verb: &[Verb::GET],
1317                params: &[],
1318                doc: None,
1319            },
1320        ];
1321        match resolve(
1322            ROUTES,
1323            "",
1324            &params_with(Verb::PUT, HashMap::new()),
1325            ControllerMode::Strict,
1326        ) {
1327            Err(WebError::MethodNotAllowed(methods)) => assert_eq!(methods, ["GET", "POST"]),
1328            other => panic!("expected 405, got {other:?}"),
1329        }
1330        // GET matches the second route → Ok.
1331        assert!(
1332            resolve(
1333                ROUTES,
1334                "",
1335                &params_with(Verb::GET, HashMap::new()),
1336                ControllerMode::Strict
1337            )
1338            .is_ok()
1339        );
1340    }
1341
1342    #[test]
1343    fn no_pattern_match_is_404_not_405() {
1344        static ROUTES: &[RouteDef] = &[RouteDef {
1345            pattern: "items",
1346            handler_id: "h",
1347            handler: "h",
1348            verb: &[Verb::GET],
1349            params: &[],
1350            doc: None,
1351        }];
1352        match resolve(
1353            ROUTES,
1354            "other",
1355            &params_with(Verb::DELETE, HashMap::new()),
1356            ControllerMode::Strict,
1357        ) {
1358            Err(WebError::NotFound) => {}
1359            other => panic!("expected 404, got {other:?}"),
1360        }
1361    }
1362
1363    #[test]
1364    fn vec_string_query_param_collects_all_values() {
1365        static ROUTES: &[RouteDef] = &[RouteDef {
1366            pattern: "",
1367            handler_id: "h",
1368            handler: "h",
1369            verb: &[Verb::GET],
1370            params: &[ParamDef {
1371                name: "tags",
1372                ty: ParamType::StringArray,
1373                source: ParamSource::Query,
1374                default: None,
1375            }],
1376            doc: None,
1377        }];
1378
1379        let mut q = HashMap::new();
1380        q.insert(
1381            "tags".to_string(),
1382            vec!["a".to_string(), "b".to_string(), "c".to_string()],
1383        );
1384        let (_, extracted) = resolve(
1385            ROUTES,
1386            "",
1387            &params_with(Verb::GET, q),
1388            ControllerMode::Strict,
1389        )
1390        .expect("route matches");
1391        assert_eq!(extracted.get_string_array("tags").unwrap(), ["a", "b", "c"]);
1392
1393        // A one-element array flows through the same path; a scalar accessor
1394        // takes the first value.
1395        let mut q1 = HashMap::new();
1396        q1.insert("tags".to_string(), vec!["solo".to_string()]);
1397        let (_, e1) = resolve(
1398            ROUTES,
1399            "",
1400            &params_with(Verb::GET, q1),
1401            ControllerMode::Strict,
1402        )
1403        .expect("route matches");
1404        assert_eq!(e1.get_string_array("tags").unwrap(), ["solo"]);
1405        assert_eq!(e1.get_string("tags").unwrap(), "solo");
1406
1407        // Absent is *not* a 400 for a `Vec<String>` param — it's the empty
1408        // list (unlike a missing required scalar).
1409        let (_, e2) = resolve(
1410            ROUTES,
1411            "",
1412            &params_with(Verb::GET, HashMap::new()),
1413            ControllerMode::Strict,
1414        )
1415        .expect("route matches with no query");
1416        assert!(e2.get_string_array("tags").unwrap().is_empty());
1417    }
1418}
1419
1420#[cfg(test)]
1421mod covering_family_tests {
1422    use super::routing::covering_family;
1423
1424    #[test]
1425    fn segment_aligned_longest_prefix_wins() {
1426        let fams = ["api", "api/auth", "public"];
1427        assert_eq!(covering_family("api/things", fams), Some("api"));
1428        assert_eq!(covering_family("api/auth", fams), Some("api/auth"));
1429        assert_eq!(covering_family("api/auth/oauth", fams), Some("api/auth"));
1430        assert_eq!(
1431            covering_family("api/authx", fams),
1432            Some("api"),
1433            "segment-aligned, not a string prefix"
1434        );
1435        assert_eq!(covering_family("apiary", fams), None);
1436        assert_eq!(covering_family("health", fams), None);
1437    }
1438
1439    #[test]
1440    fn star_sugar_and_root() {
1441        assert_eq!(covering_family("api/things", ["api/*"]), Some("api/*"));
1442        assert_eq!(covering_family("anything/at/all", ["*"]), Some("*"));
1443        assert_eq!(covering_family("", [""]), Some(""));
1444        assert_eq!(covering_family("/api/", ["api"]), Some("api"));
1445    }
1446
1447    #[test]
1448    fn a_later_identical_prefix_wins_like_the_macro() {
1449        assert_eq!(covering_family("api/x", ["api", "api/*"]), Some("api/*"));
1450    }
1451}
1452
1453#[cfg(test)]
1454mod bool_default_tests {
1455    //! ⛔ **A declared `bool` default must actually reach the handler.**
1456    //!
1457    //! `bool` is the only parameter type whose *absence* is a usable value, so
1458    //! `get_bool` answers `Ok(false)` for a missing parameter rather than `Err`.
1459    //! Every other type reaches its declared default because the generated code is
1460    //! `get_x(name).unwrap_or(default)` and `get_x` **errors** when the parameter is
1461    //! missing — so for `bool` that `unwrap_or` unwrapped an `Ok(false)` and the
1462    //! default was **dead code**.
1463    //!
1464    //! ⚠️ Measured in a consumer on 2026-09-04: a cancel route declaring
1465    //! `at_period_end: bool = true`, and documenting the reversible at-period-end
1466    //! form as its default, cancelled **immediately** whenever the client omitted the
1467    //! parameter. Destructive direction, opposite of the documented promise, and
1468    //! invisible because the route worked perfectly when the parameter *was* sent.
1469    use super::*;
1470
1471    fn params(query: &[(&str, &str)]) -> ExtractedParams {
1472        let mut q: HashMap<String, Vec<String>> = HashMap::new();
1473        for (k, v) in query {
1474            q.entry((*k).to_string())
1475                .or_default()
1476                .push((*v).to_string());
1477        }
1478        ExtractedParams {
1479            path: HashMap::new(),
1480            query: q,
1481            body: None,
1482            raw_body: Bytes::new(),
1483        }
1484    }
1485
1486    #[test]
1487    fn an_absent_bool_is_distinguishable_from_an_explicit_false() {
1488        let absent = params(&[]);
1489        assert_eq!(
1490            absent.get_bool_optional("flag").unwrap(),
1491            None,
1492            "absent must be None, or a declared default has nothing to fall back from"
1493        );
1494        assert_eq!(
1495            params(&[("flag", "false")])
1496                .get_bool_optional("flag")
1497                .unwrap(),
1498            Some(false),
1499            "an explicit `false` is a VALUE, and must not be confused with absence — \
1500             that conflation is the whole defect"
1501        );
1502        assert_eq!(
1503            params(&[("flag", "true")])
1504                .get_bool_optional("flag")
1505                .unwrap(),
1506            Some(true)
1507        );
1508
1509        // ⭐ The generated shape, verbatim: this is what a `param: bool = true`
1510        // declaration compiles to, and what silently yielded `false` before.
1511        let d = true;
1512        assert!(
1513            absent.get_bool_optional("flag").unwrap().unwrap_or(d),
1514            "⛔ a declared default of `true` must survive an omitted parameter"
1515        );
1516        assert!(
1517            !params(&[("flag", "false")])
1518                .get_bool_optional("flag")
1519                .unwrap()
1520                .unwrap_or(d),
1521            "…and an explicit `false` must still override that default"
1522        );
1523    }
1524
1525    #[test]
1526    fn get_bool_errors_on_absence_like_every_other_scalar_getter() {
1527        // ⛔ This test used to assert the opposite, on the stated grounds that a
1528        // bare `param: bool` means "false unless asked for" and erroring would
1529        // turn `confirm` / `dry_run` into `400`s. That was never true — a bare
1530        // `bool` is required and `resolve` 400s it before extraction (see
1531        // `routing::param_is_required`) — and a red test carrying a confident
1532        // wrong reason is what would stop the next person from fixing it.
1533        assert!(
1534            params(&[]).get_bool("confirm").is_err(),
1535            "absence is an `Err` here, as it is for get_string / get_i64 / the rest"
1536        );
1537        // Present values parse exactly as before.
1538        assert!(params(&[("confirm", "1")]).get_bool("confirm").unwrap());
1539        assert!(!params(&[("confirm", "0")]).get_bool("confirm").unwrap());
1540        assert!(!params(&[("confirm", "false")]).get_bool("confirm").unwrap());
1541        assert!(!params(&[("confirm", "")]).get_bool("confirm").unwrap());
1542    }
1543}
1544
1545#[cfg(test)]
1546mod param_requiredness_tests {
1547    //! ⭐ **The requiredness rule is one predicate, and this is where the
1548    //! decision it encodes is written down.**
1549    //!
1550    //! `routing::resolve` (which 400s) and the OpenAPI generator (which reports
1551    //! `required`) both call [`routing::param_is_required`]. They used to spell
1552    //! the rule out separately and agreed only by diligence; a third site —
1553    //! `ExtractedParams::get_bool`'s `unwrap_or(false)` — quietly encoded the
1554    //! *opposite* rule for `bool`, and that disagreement is what made a declared
1555    //! `bool` default unreachable (fixed 2026-09-04).
1556    use super::routing::param_is_required;
1557    use super::*;
1558
1559    fn q(ty: ParamType, default: Option<ParamDefault>) -> ParamDef {
1560        ParamDef {
1561            name: "p",
1562            ty,
1563            source: ParamSource::Query,
1564            default,
1565        }
1566    }
1567
1568    #[test]
1569    fn requiredness_is_syntactic_and_uniform_across_scalar_types() {
1570        // ⭐ The property worth having: whether a parameter is required is
1571        // readable off `routes!` without knowing the type. `name: T` is
1572        // required; `name: T = x` is not. No per-type table.
1573        for ty in [
1574            ParamType::String,
1575            ParamType::Int,
1576            ParamType::U64,
1577            ParamType::U32,
1578            ParamType::F64,
1579            ParamType::Bool,
1580        ] {
1581            assert!(
1582                param_is_required(&q(ty, None)),
1583                "a bare `{ty:?}` query param is required"
1584            );
1585        }
1586        assert!(!param_is_required(&q(
1587            ParamType::String,
1588            Some(ParamDefault::String("x"))
1589        )));
1590        assert!(!param_is_required(&q(
1591            ParamType::U32,
1592            Some(ParamDefault::U32(1))
1593        )));
1594        assert!(!param_is_required(&q(
1595            ParamType::Bool,
1596            Some(ParamDefault::Bool(true))
1597        )));
1598    }
1599
1600    #[test]
1601    fn a_bare_bool_is_required_and_that_is_the_deliberate_choice() {
1602        // ⛔ Do not "fix" this into `false unless asked for`. Exempting `bool`
1603        // would leave NO way to declare a required one, and it would discard a
1604        // distinction the wire actually carries — absent and `?p=false` are
1605        // different requests (see `ExtractedParams::get_bool_optional`).
1606        // An optional flag is spelled `confirm: bool = false`.
1607        assert!(param_is_required(&q(ParamType::Bool, None)));
1608        assert!(!param_is_required(&q(
1609            ParamType::Bool,
1610            Some(ParamDefault::Bool(false))
1611        )));
1612    }
1613
1614    #[test]
1615    fn string_array_is_the_one_exemption_and_it_is_forced_not_chosen() {
1616        // ⚖️ urlencoding cannot express "present but empty", so there is no
1617        // required/optional distinction available to lose. That is the bar a
1618        // future exemption has to clear — a natural zero value is not enough.
1619        assert!(!param_is_required(&q(ParamType::StringArray, None)));
1620    }
1621
1622    #[test]
1623    fn a_path_capture_is_always_required() {
1624        // The pattern matched, so the capture is present; absence never arises.
1625        assert!(param_is_required(&ParamDef {
1626            name: "id",
1627            ty: ParamType::U64,
1628            source: ParamSource::Path,
1629            default: None,
1630        }));
1631    }
1632}