Ensure legacy /oauth path still works for GitHub

changelog.d/1105.bugfix

@@ -0,0 +1 @@
+Fix /oauth responding with 405 despite GitHub being configured.

spec/github.spec.ts

@@ -43,6 +43,11 @@ describe("GitHub", () => {
           webhook: {
             secret: randomUUID(),
           },
+          oauth: {
+            client_id: "GITHUB_ID",
+            client_secret: "GITHUB_SECRET",
+            redirect_uri: "http://example.org/redirectme",
+          },
           // So we can mock out the URL
           enterpriseUrl: `http://localhost:${githubPort}`,
           auth: {
@@ -168,4 +173,14 @@ describe("GitHub", () => {
       expect(body).toContain("My test pull request");
     },
   );
+
+  test.each(["/oauth", "/github/oauth"])(
+    "should redirect invalid oauth requests to oauth.html",
+    async (path) => {
+      // This simply tests that oauth requests do not end up being ignored.
+      const req = await fetch(`http://localhost:${webhooksPort}${path}`);
+      expect(req.url.startsWith(`http://localhost:${webhooksPort}/oauth.html`))
+        .to.be.true;
+    },
+  );
 });

src/Webhooks.ts

@@ -36,6 +36,11 @@
         this.config.widgets?.parsedPublicUrl,
       );
       this.expressRouter.use("/github", this.github.getRouter());
+      // LEGACY PATH - Will be removed in a future release.
+      this.expressRouter.get(
+        "/oauth",
+        this.github.onGetOAuth.bind(this.github),
+      );
     }
 
     if (this.config.gitlab) {
@@ -94,9 +99,6 @@
 
     // LEGACY PATHS. These will be removed in a future version.
     this.expressRouter.post("/", this.onPayload.bind(this));
-    if (this.github) {
-      this.expressRouter.get("/oauth", this.github.onGetOAuth.bind(this));
-    }
   }
 
   public stop() {

src/github/Router.ts

@@ -174,13 +174,13 @@
 
     const { setup_action: setupAction, state } = req.query;
     log.info("Got new oauth request", { state, setupAction });
+    if (!this.config.oauth) {
+      throw new ApiError(
+        "Bridge is not configured with OAuth support",
+        ErrCode.DisabledFeature,
+      );
+    }
     try {
-      if (!this.config.oauth) {
-        throw new ApiError(
-          "Bridge is not configured with OAuth support",
-          ErrCode.DisabledFeature,
-        );
-      }
       if (req.query.error) {
         throw new ApiError(
           `GitHub Error: ${req.query.error} ${req.query.error_description}`,
@@ -291,9 +291,9 @@
 
   public getRouter() {
     const router = Router();
+    router.get("/oauth", this.onGetOAuth.bind(this));
     router.use(json({ verify: this.verifyRequest.bind(this) }));
     router.post("/webhook", this.onWebhook.bind(this));
-    router.get("/oauth", this.onGetOAuth.bind(this));
     return router;
   }
 }