web/builds: API to request rebuild of a crate version

This resolves rust-lang#2442.

- adds config variable `DOCSRS_TRIGGER_REBUILD_TOKEN` /
  `Config.trigger_rebuild_token`

- adds `build_trigger_rebuild_handler` and route
  "/crate/:name/:version/rebuild"

Note: does not yet contain any kind of rate limiting!

src/build_queue.rs

@@ -151,7 +151,7 @@ impl BuildQueue {
             .collect())
     }
 
-    fn has_build_queued(&self, name: &str, version: &str) -> Result<bool> {
+    pub(crate) fn has_build_queued(&self, name: &str, version: &str) -> Result<bool> {
         Ok(self
             .db
             .get()?

src/config.rs

@@ -41,6 +41,10 @@ pub struct Config {
     // Gitlab authentication
     pub(crate) gitlab_accesstoken: Option<String>,
 
+    // Access token for rebuild trigger at path
+    // "/crate/:name/:version/rebuild"
+    pub(crate) trigger_rebuild_token: Option<String>,
+
     // amount of retries for external API calls, mostly crates.io
     pub crates_io_api_call_retries: u32,
 
@@ -176,6 +180,8 @@ impl Config {
 
             gitlab_accesstoken: maybe_env("DOCSRS_GITLAB_ACCESSTOKEN")?,
 
+            trigger_rebuild_token: maybe_env("DOCSRS_TRIGGER_REBUILD_TOKEN")?,
+
             max_file_size: env("DOCSRS_MAX_FILE_SIZE", 50 * 1024 * 1024)?,
             max_file_size_html: env("DOCSRS_MAX_FILE_SIZE_HTML", 50 * 1024 * 1024)?,
             // LOL HTML only uses as much memory as the size of the start tag!

src/web/builds.rs

@@ -1,22 +1,33 @@
-use super::{cache::CachePolicy, error::AxumNope, headers::CanonicalUrl};
+use super::{
+    cache::CachePolicy,
+    error::{AxumNope, JsonAxumNope, JsonAxumResult},
+    headers::CanonicalUrl,
+};
 use crate::{
     db::types::BuildStatus,
     docbuilder::Limits,
     impl_axum_webpage,
+    utils::spawn_blocking,
     web::{
+        crate_details::CrateDetails,
         error::AxumResult,
         extractors::{DbConnection, Path},
         match_version, MetaData, ReqVersion,
     },
-    Config,
+    BuildQueue, Config,
 };
-use anyhow::Result;
+use anyhow::{anyhow, Result};
 use axum::{
     extract::Extension, http::header::ACCESS_CONTROL_ALLOW_ORIGIN, response::IntoResponse, Json,
 };
+use axum_extra::{
+    headers::{authorization::Bearer, Authorization},
+    TypedHeader,
+};
 use chrono::{DateTime, Utc};
 use semver::Version;
 use serde::Serialize;
+use serde_json::json;
 use std::sync::Arc;
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize)]
@@ -111,6 +122,81 @@ pub(crate) async fn build_list_json_handler(
         .into_response())
 }
 
+async fn build_trigger_check(
+    mut conn: DbConnection,
+    name: &String,
+    version: &Version,
+    build_queue: &Arc<BuildQueue>,
+) -> AxumResult<impl IntoResponse> {
+    let _ = CrateDetails::new(&mut *conn, &name, &version, None, vec![])
+        .await?
+        .ok_or(AxumNope::VersionNotFound)?;
+
+    let crate_version_is_in_queue = spawn_blocking({
+        let name = name.clone();
+        let version_string = version.to_string();
+        let build_queue = build_queue.clone();
+        move || build_queue.has_build_queued(&name, &version_string)
+    })
+    .await?;
+    if crate_version_is_in_queue {
+        return Err(AxumNope::BadRequest(anyhow!(
+            "crate {name} {version} already queued for rebuild"
+        )));
+    }
+
+    Ok(())
+}
+
+// Priority according to issue #2442; positive here as it's inverted.
+// FUTURE: move to a crate-global enum with all special priorities?
+const TRIGGERED_REBUILD_PRIORITY: i32 = 5;
+
+pub(crate) async fn build_trigger_rebuild_handler(
+    Path((name, version)): Path<(String, Version)>,
+    conn: DbConnection,
+    Extension(build_queue): Extension<Arc<BuildQueue>>,
+    Extension(config): Extension<Arc<Config>>,
+    opt_auth_header: Option<TypedHeader<Authorization<Bearer>>>,
+) -> JsonAxumResult<impl IntoResponse> {
+    let expected_token =
+        config
+            .trigger_rebuild_token
+            .as_ref()
+            .ok_or(JsonAxumNope(AxumNope::InternalError(anyhow!(
+                "access token `trigger_rebuild_token` \
+                     is not configured"
+            ))))?;
+
+    // (Future: would it be better to have standard middleware handle auth?)
+    let TypedHeader(auth_header) =
+        opt_auth_header.ok_or(JsonAxumNope(AxumNope::MissingAuthenticationToken))?;
+    if auth_header.token() != expected_token {
+        return Err(JsonAxumNope(AxumNope::InvalidAuthenticationToken));
+    }
+
+    build_trigger_check(conn, &name, &version, &build_queue)
+        .await
+        .map_err(JsonAxumNope)?;
+
+    spawn_blocking({
+        let name = name.clone();
+        let version_string = version.to_string();
+        move || {
+            build_queue.add_crate(
+                &name,
+                &version_string,
+                TRIGGERED_REBUILD_PRIORITY,
+                None, /* because crates.io is the only service that calls this endpoint */
+            )
+        }
+    })
+    .await
+    .map_err(|e| JsonAxumNope(e.into()))?;
+
+    Ok(Json(json!({})))
+}
+
 async fn get_builds(
     conn: &mut sqlx::PgConnection,
     name: &str,
@@ -276,6 +362,119 @@ mod tests {
         });
     }
 
+    #[test]
+    fn build_trigger_rebuild_missing_config() {
+        wrapper(|env| {
+            env.fake_release().name("foo").version("0.1.0").create()?;
+
+            {
+                let response = env.frontend().get("/crate/regex/1.3.1/rebuild").send()?;
+                // Needs POST
+                assert_eq!(response.status(), StatusCode::METHOD_NOT_ALLOWED);
+            }
+
+            {
+                let response = env.frontend().post("/crate/regex/1.3.1/rebuild").send()?;
+                assert_eq!(response.status(), StatusCode::INTERNAL_SERVER_ERROR);
+                let text = response.text()?;
+                assert!(text.contains("access token `trigger_rebuild_token` is not configured"));
+                let json: serde_json::Value = serde_json::from_str(&text)?;
+                assert_eq!(
+                    json,
+                    serde_json::json!({
+                        "title": "Internal Server Error",
+                        "message": "access token `trigger_rebuild_token` is not configured"
+                    })
+                );
+            }
+
+            Ok(())
+        })
+    }
+
+    #[test]
+    fn build_trigger_rebuild_with_config() {
+        wrapper(|env| {
+            let correct_token = "foo137";
+            env.override_config(|config| config.trigger_rebuild_token = Some(correct_token.into()));
+
+            env.fake_release().name("foo").version("0.1.0").create()?;
+
+            {
+                let response = env.frontend().post("/crate/regex/1.3.1/rebuild").send()?;
+                assert_eq!(response.status(), StatusCode::UNAUTHORIZED);
+                let text = response.text()?;
+                let json: serde_json::Value = serde_json::from_str(&text)?;
+                assert_eq!(
+                    json,
+                    serde_json::json!({
+                        "title": "Missing authentication token",
+                        "message": "The token used for authentication is missing"
+                    })
+                );
+            }
+
+            {
+                let response = env
+                    .frontend()
+                    .post("/crate/regex/1.3.1/rebuild")
+                    .bearer_auth("someinvalidtoken")
+                    .send()?;
+                assert_eq!(response.status(), StatusCode::UNAUTHORIZED);
+                let text = response.text()?;
+                let json: serde_json::Value = serde_json::from_str(&text)?;
+                assert_eq!(
+                    json,
+                    serde_json::json!({
+                        "title": "Invalid authentication token",
+                        "message": "The token used for authentication is not valid"
+                    })
+                );
+            }
+
+            assert_eq!(env.build_queue().pending_count()?, 0);
+            assert!(!env.build_queue().has_build_queued("foo", "0.1.0")?);
+
+            {
+                let response = env
+                    .frontend()
+                    .post("/crate/foo/0.1.0/rebuild")
+                    .bearer_auth(correct_token)
+                    .send()?;
+                assert_eq!(response.status(), StatusCode::OK);
+                let text = response.text()?;
+                let json: serde_json::Value = serde_json::from_str(&text)?;
+                assert_eq!(json, serde_json::json!({}));
+            }
+
+            assert_eq!(env.build_queue().pending_count()?, 1);
+            assert!(env.build_queue().has_build_queued("foo", "0.1.0")?);
+
+            {
+                let response = env
+                    .frontend()
+                    .post("/crate/foo/0.1.0/rebuild")
+                    .bearer_auth(correct_token)
+                    .send()?;
+                assert_eq!(response.status(), StatusCode::BAD_REQUEST);
+                let text = response.text()?;
+                let json: serde_json::Value = serde_json::from_str(&text)?;
+                assert_eq!(
+                    json,
+                    serde_json::json!({
+                        "title": "Bad request",
+                        "message": "crate foo 0.1.0 already queued for rebuild"
+                    })
+                );
+            }
+
+            assert_eq!(env.build_queue().pending_count()?, 1);
+            assert!(env.build_queue().has_build_queued("foo", "0.1.0")?);
+
+            Ok(())
+        });
+    }
+
     #[test]
     fn build_empty_list() {
         wrapper(|env| {

src/web/crate_details.rs

@@ -126,7 +126,7 @@ impl CrateDetails {
         .unwrap())
     }
 
-    async fn new(
+    pub(crate) async fn new(
         conn: &mut sqlx::PgConnection,
         name: &str,
         version: &Version,

src/web/error.rs

@@ -173,7 +173,6 @@ impl ErrorResponse {
             }) => (
                 status,
                 Json(serde_json::json!({
-                    "result": "err", // XXX
                     "title": title,
                     "message": message,
                 })),

src/web/routes.rs

@@ -224,6 +224,10 @@ pub(super) fn build_axum_routes() -> AxumRouter {
             "/crate/:name/:version/builds.json",
             get_internal(super::builds::build_list_json_handler),
         )
+        .route(
+            "/crate/:name/:version/rebuild",
+            post_internal(super::builds::build_trigger_rebuild_handler),
+        )
         .route(
             "/crate/:name/:version/status.json",
             get_internal(super::status::status_handler),