Add pretty querstring to allow pretty print json debugging

Author: jakewmeyer

package.json

@@ -32,6 +32,7 @@
     "koa": "^2.5.2",
     "koa-compress": "^3.0.0",
     "koa-helmet": "^4.0.0",
+    "koa-is-json": "^1.0.0",
     "koa-logger": "^3.2.0",
     "koa-pino-logger": "^2.1.3",
     "koa-redis-cache": "^3.0.1",

src/app.js

@@ -6,6 +6,7 @@ const helmet = require('koa-helmet');
 const Koa = require('koa');
 const logger = require('koa-pino-logger');
 const MongoClient = require('mongodb');
+const json = require('./middleware/json');
 const options = require('./middleware/redis');
 
 const capsules = require('./routes/v2-capsules');
@@ -66,6 +67,10 @@ if (process.env.NODE_ENV === 'production') {
   app.use(cache(options));
 }
 
+// Allow pretty print via pretty=true querystring
+// Pretty printed json will NOT be cached
+app.use(json({ pretty: false, param: { pretty: true } }));
+
 // Koa routes
 app.use(capsules.routes());
 app.use(errors.routes());

src/middleware/json.js

@@ -0,0 +1,36 @@
+
+const isJSON = require('koa-is-json');
+
+/**
+ * Pretty JSON response middleware.
+ *
+ *  - `pretty` default to pretty response [true]
+ *  - `param` optional query-string param for pretty responses [none]
+ *
+ * @param {Object} opts
+ * @return {GeneratorFunction}
+ * @api public
+ */
+
+module.exports = (opts = {}) => {
+  const param = opts.param;
+  const pretty = opts.pretty === false ? true : opts.pretty;
+  const spaces = opts.spaces || 2;
+
+  return (ctx, next) => {
+    return next().then(() => {
+      const body = ctx.body;
+      const json = isJSON(body);
+      if (!json) return;
+
+      // query
+      const hasParam = param.pretty === true && ctx.query.pretty === 'true';
+      const prettify = pretty && hasParam;
+
+      // prettify JSON responses
+      if (json && prettify) {
+        ctx.body = JSON.stringify(body, null, spaces);
+      }
+    });
+  };
+};

src/middleware/redis.js

@@ -44,6 +44,7 @@ if (process.env.REDISCLOUD_URL) {
       path: '/v2/capsules/(.*)',
       expire: 86400,
     }],
+    passParam: 'pretty',
     redis: {
       host: redisURL.hostname,
       port: redisURL.port,
@@ -88,6 +89,7 @@ if (process.env.REDISCLOUD_URL) {
       path: '/v2/capsules/(.*)',
       expire: 86400,
     }],
+    passParam: 'pretty',
   };
 }