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lenso_api/
openapi.rs

1//! `OpenAPI` document assembly.
2//!
3//! Paths and component schemas are derived directly from the
4//! `#[utoipa::path]`-annotated handlers via `utoipa-axum`'s `OpenApiRouter`, so
5//! there is a single source of truth per endpoint. This module contributes the
6//! document-level metadata (info, tags) and normalizes shared platform error
7//! responses after linked/module routers are merged.
8
9use lenso_bootstrap::CompositionProfile;
10use platform_core::AppContext;
11use platform_http::{ApiOpenApiRouter, OpenApiRouter, base_router};
12use utoipa::OpenApi;
13use utoipa::openapi::RefOr;
14use utoipa::openapi::content::Content;
15use utoipa::openapi::path::Operation;
16use utoipa::openapi::response::Response;
17
18/// Document-level `OpenAPI` metadata shared by every endpoint.
19///
20/// Intentionally declares no `paths` and no per-endpoint `schemas`: those are
21/// collected automatically from the annotated handlers when the router is split
22/// into its parts.
23#[derive(OpenApi)]
24#[openapi(
25    info(
26        title = "Lenso API",
27        version = "1.0.0",
28        description = "Rust-first modular monolith API contract"
29    ),
30    tags(
31        (name = "auth", description = "Auth module development session APIs"),
32        (name = "admin-runtime", description = "Read-only runtime console APIs"),
33        (name = "admin-config", description = "Editable configuration console APIs"),
34        (name = "admin-data", description = "Schema-driven admin data console APIs")
35    )
36)]
37struct ApiDoc;
38
39/// Assemble the full `OpenAPI` router: base probes, linked module routes, and
40/// admin/runtime routers, seeded with the document-level metadata.
41///
42/// Context-free: route registration and `OpenAPI` metadata never touch the
43/// database, so callers can either serve it (after `with_state` +
44/// `split_for_parts`) or extract the `OpenAPI` document alone.
45pub(crate) fn api_router() -> ApiOpenApiRouter {
46    api_router_for_profile(CompositionProfile::default())
47}
48
49pub(crate) fn api_router_for_profile(profile: CompositionProfile) -> ApiOpenApiRouter {
50    let base = OpenApiRouter::with_openapi(openapi_document_for_profile_with_composition(
51        profile,
52        &lenso_bootstrap::HostComposition::default(),
53    ))
54    .merge(base_router());
55    lenso_bootstrap::merge_linked_http_for_profile(base, profile)
56        .merge(platform_admin::router())
57        .merge(platform_admin_data::router())
58        .merge(platform_module_remote::router())
59}
60
61pub(crate) fn api_router_for_context_with_composition(
62    ctx: &AppContext,
63    composition: &lenso_bootstrap::HostComposition,
64) -> platform_core::AppResult<ApiOpenApiRouter> {
65    let profile = CompositionProfile::from_config(&ctx.config)?;
66    let base = OpenApiRouter::with_openapi(openapi_document_for_profile_with_composition(
67        profile,
68        composition,
69    ))
70    .merge(base_router());
71    Ok(
72        lenso_bootstrap::merge_linked_http_for_context_with_composition(base, ctx, composition)?
73            .merge(platform_admin::router())
74            .merge(platform_admin_data::router())
75            .merge(platform_module_remote::router()),
76    )
77}
78
79fn openapi_document_for_profile_with_composition(
80    profile: CompositionProfile,
81    composition: &lenso_bootstrap::HostComposition,
82) -> utoipa::openapi::OpenApi {
83    let mut document = ApiDoc::openapi();
84    if let Some(tags) = &mut document.tags {
85        let has_auth = profile == CompositionProfile::Demo
86            || composition
87                .linked_modules()
88                .iter()
89                .any(|module| module.module_name == "auth");
90        match profile {
91            CompositionProfile::Core => tags.retain(|tag| has_auth || tag.name != "auth"),
92            CompositionProfile::Demo => {}
93        }
94    }
95    document
96}
97
98/// The committed `OpenAPI` document, derived from the annotated handlers.
99#[must_use]
100pub fn openapi_document() -> utoipa::openapi::OpenApi {
101    let mut document = api_router().to_openapi();
102    normalize_error_response_content_types(&mut document);
103    document
104}
105
106pub(crate) fn normalize_error_response_content_types(document: &mut utoipa::openapi::OpenApi) {
107    for path_item in document.paths.paths.values_mut() {
108        normalize_operation_error_responses(path_item.get.as_mut());
109        normalize_operation_error_responses(path_item.put.as_mut());
110        normalize_operation_error_responses(path_item.post.as_mut());
111        normalize_operation_error_responses(path_item.delete.as_mut());
112        normalize_operation_error_responses(path_item.options.as_mut());
113        normalize_operation_error_responses(path_item.head.as_mut());
114        normalize_operation_error_responses(path_item.patch.as_mut());
115        normalize_operation_error_responses(path_item.trace.as_mut());
116    }
117}
118
119fn normalize_operation_error_responses(operation: Option<&mut Operation>) {
120    let Some(operation) = operation else {
121        return;
122    };
123    for response in operation.responses.responses.values_mut() {
124        if let RefOr::T(response) = response {
125            normalize_response_error_content_type(response);
126        }
127    }
128}
129
130fn normalize_response_error_content_type(response: &mut Response) {
131    let Some(content) = response.content.get("application/json") else {
132        return;
133    };
134    if !is_error_response_content(content) {
135        return;
136    }
137
138    let content = response
139        .content
140        .shift_remove("application/json")
141        .expect("application/json content should exist");
142    response
143        .content
144        .insert("application/problem+json".to_owned(), content);
145}
146
147fn is_error_response_content(content: &Content) -> bool {
148    matches!(
149        &content.schema,
150        Some(RefOr::Ref(reference))
151            if reference.ref_location == "#/components/schemas/ErrorResponse"
152    )
153}