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apimock_server/
respond_response.rs

1//! Turn a matched `Respond` declaration into an HTTP response.
2//!
3//! # Why this is a server-side free function and not a `Respond` method
4//!
5//! Pre-5.0, `Respond::response(...)` lived on the type itself. That
6//! method built a `hyper::Response<BoxBody>` and touched the server's
7//! file-response / text-response / status-response helpers. To keep
8//! `apimock-routing` free of hyper-body construction (so a future GUI
9//! can depend on it cheaply), that work moved here.
10
11use apimock_routing::{ParsedRequest, Respond};
12use console::style;
13use std::path::Path;
14
15use crate::{
16    http_util::delay_response,
17    respond_util::full_file_path,
18    response::{
19        error_response::internal_server_error_response,
20        file_response::FileResponse,
21        json_response::json_response,
22        status_code_response::{status_code_response, status_code_response_with_message},
23        text_response::text_response,
24    },
25    types::BoxBody,
26};
27
28/// Produce the HTTP response for a matched `Respond` declaration.
29///
30/// # Why the branches are ordered file → text → json → status → error
31///
32/// The fields are mutually specialised (RFC 065: `file_path`, `text`
33/// and `json` are the three body sources, `Respond::validate` rejects
34/// more than one being set):
35/// - `file_path` serves a file (possibly with CSV→JSON conversion).
36/// - `text` + `status` yields a custom-status text response.
37/// - `text` alone yields a plain 200 text response.
38/// - `json` (+ an optional `status`) yields an `application/json`
39///   response, parsed with the same JSON5 parser `Respond::validate`
40///   already checked it against at load time.
41/// - `status` alone yields an empty body with that status.
42///
43/// `Respond::validate` rejects nonsensical combinations at startup, so
44/// hitting the final `Err` branch means something slipped past
45/// validation — a real bug, not user input.
46///
47/// `rule_set_default_delay_ms` is the matched rule set's
48/// `[default].delay_response_milliseconds`, if any (RFC 045 Defect 2).
49/// The per-rule `respond.delay_response_milliseconds` always overrides
50/// it when both are set; the rule-set value only applies when the rule
51/// itself is silent.
52pub async fn respond_response(
53    respond: &Respond,
54    dir_prefix: &str,
55    parsed_request: &ParsedRequest,
56    rule_set_default_delay_ms: Option<u32>,
57    confine_to: Option<&Path>,
58    cors_allow_credentials_origins: &[String],
59) -> Result<hyper::Response<BoxBody>, hyper::http::Error> {
60    if let Some(delay_ms) = respond
61        .delay_response_milliseconds
62        .or(rule_set_default_delay_ms)
63    {
64        delay_response(delay_ms).await;
65    }
66
67    let request_headers = &parsed_request.component_parts.headers;
68
69    // file_path → file/CSV/JSON response
70    if let Some(file_path) = respond.file_path.as_ref() {
71        let Some(full_file_path) = full_file_path(file_path.as_str(), dir_prefix) else {
72            log::error!(
73                "{}:\n{} (prefix = {})",
74                style("file not found").red(),
75                file_path,
76                dir_prefix,
77            );
78            return internal_server_error_response(
79                "failed to get response file",
80                request_headers,
81                cors_allow_credentials_origins,
82            );
83        };
84
85        return FileResponse::new_with_csv_records_jsonpath(
86            full_file_path.as_str(),
87            respond.headers.as_ref(),
88            respond.csv_records_key.clone(),
89            request_headers,
90            confine_to,
91            cors_allow_credentials_origins,
92        )
93        .file_content_response()
94        .await;
95    }
96
97    if let Some(text) = respond.text.as_ref() {
98        return match respond.status_code.as_ref() {
99            Some(status_code) => status_code_response_with_message(
100                status_code,
101                text.as_str(),
102                respond.headers.as_ref(),
103                request_headers,
104                cors_allow_credentials_origins,
105            ),
106            None => text_response(
107                text.as_str(),
108                None,
109                respond.headers.as_ref(),
110                request_headers,
111                cors_allow_credentials_origins,
112            ),
113        };
114    }
115
116    if let Some(json_str) = respond.json.as_ref() {
117        return json_response(
118            json_str.as_str(),
119            respond.status_code.as_ref(),
120            respond.headers.as_ref(),
121            request_headers,
122            None,
123            cors_allow_credentials_origins,
124        );
125    }
126
127    if let Some(status_code) = respond.status_code.as_ref() {
128        return status_code_response(
129            status_code,
130            respond.headers.as_ref(),
131            request_headers,
132            cors_allow_credentials_origins,
133        );
134    }
135
136    internal_server_error_response(
137        "invalid respond def",
138        request_headers,
139        cors_allow_credentials_origins,
140    )
141}