feat: make api only return json (#42320)

* fix(api): return json for delete + reset-progress

* refactor(api): make .json calls explicit

These .send() calls had objects as arguments. Using .json() makes it
explicit without changing behaviour.

* fix: return json or redirectWithFlash

We should never be getting requests for plain text, but if we do they
should be redirected back to the client.

* fix: prioritize JSON responses

If accepted, respond with JSON.  If not, it's probably a bad request.

api-server/src/server/boot/challenge.js

@@ -286,7 +286,7 @@ function projectCompleted(req, res, next) {
         })
       );
       return Observable.fromPromise(updatePromise).doOnNext(() => {
-        return res.send({
+        return res.json({
           alreadyCompleted,
           points: alreadyCompleted ? user.points : user.points + 1,
           completedDate: completedChallenge.completedDate
@@ -320,7 +320,7 @@ function backendChallengeCompleted(req, res, next) {
         })
       );
       return Observable.fromPromise(updatePromise).doOnNext(() => {
-        return res.send({
+        return res.json({
           alreadyCompleted,
           points: alreadyCompleted ? user.points : user.points + 1,
           completedDate: completedChallenge.completedDate

api-server/src/server/boot/donate.js

@@ -20,7 +20,7 @@ export default function donateBoot(app, done) {
     if (!user || !body) {
       return res
         .status(500)
-        .send({ error: 'User must be signed in for this request.' });
+        .json({ error: 'User must be signed in for this request.' });
     }
     return Promise.resolve(req)
       .then(
@@ -31,7 +31,7 @@ export default function donateBoot(app, done) {
       .then(() => res.status(200).json({ isDonating: true }))
       .catch(err => {
         log(err.message);
-        return res.status(500).send({
+        return res.status(500).json({
           type: 'danger',
           message: 'Something went wrong.'
         });

api-server/src/server/boot/randomAPIs.js

@@ -193,7 +193,7 @@ module.exports = function (app) {
               pulls === parseInt(pulls, 10) && issues
                 ? Object.keys(JSON.parse(issues)).length - pulls
                 : "Can't connect to GitHub";
-            return res.send({
+            return res.json({
               issues: issues,
               pulls: pulls
             });

api-server/src/server/boot/user.js

@@ -185,7 +185,7 @@ function postResetProgress(req, res, next) {
       if (err) {
         return next(err);
       }
-      return res.sendStatus(200);
+      return res.status(200).json({});
     }
   );
 }
@@ -199,7 +199,7 @@ function createPostDeleteAccount(app) {
       }
       req.logout();
       removeCookies(req, res);
-      return res.sendStatus(200);
+      return res.status(200).json({});
     });
   };
 }

api-server/src/server/boot/z-not-found.js

@@ -4,20 +4,16 @@ import { getRedirectParams } from '../utils/redirection';
 export default function fourOhFour(app) {
   app.all('*', function (req, res) {
     const accept = accepts(req);
-    const type = accept.type('html', 'json', 'text');
+    // prioritise returning json
+    const type = accept.type('json', 'html', 'text');
     const { path } = req;
     const { origin } = getRedirectParams(req);
 
-    if (type === 'html') {
+    if (type === 'json') {
+      return res.status('404').json({ error: 'path not found' });
+    } else {
       req.flash('danger', `We couldn't find path ${path}`);
       return res.redirectWithFlash(`${origin}/404`);
     }
-
-    if (type === 'json') {
-      return res.status('404').json({ error: 'path not found' });
-    }
-
-    res.setHeader('Content-Type', 'text/plain');
-    return res.send('404 path not found');
   });
 }

api-server/src/server/middlewares/error-handlers.js

@@ -37,7 +37,8 @@ export default function prodErrorHandler() {
 
     // parse res type
     const accept = accepts(req);
-    const type = accept.type('html', 'json', 'text');
+    // prioritise returning json
+    const type = accept.type('json', 'html', 'text');
 
     const redirectTo = handled.redirectTo || `${origin}/`;
     const message =
@@ -48,22 +49,16 @@ export default function prodErrorHandler() {
       console.error(errTemplate(err, req));
     }
 
-    if (type === 'html') {
+    if (type === 'json') {
+      return res.json({
+        type: handled.type || 'errors',
+        message
+      });
+    } else {
       if (typeof req.flash === 'function') {
         req.flash(handled.type || 'danger', message);
       }
       return res.redirectWithFlash(redirectTo);
-      // json
-    } else if (type === 'json') {
-      res.setHeader('Content-Type', 'application/json');
-      return res.send({
-        type: handled.type || 'errors',
-        message
-      });
-      // plain text
-    } else {
-      res.setHeader('Content-Type', 'text/plain');
-      return res.send(message);
     }
   };
 }