feat: allow /ipns/webui.ipfs.io on api port

We want to allow user to try out the latest versions of the webui
before they are officially released with js-ipfs.

Context: ipfs/ipfs-companion#736
go-ipfs counterpart: ipfs/kubo#6530

License: MIT
Signed-off-by: Marcin Rataj <lidel@lidel.org>

src/http/api/routes/webui.js

@@ -1,18 +1,35 @@
 'use strict'
 
 const Joi = require('@hapi/joi')
+const Boom = require('@hapi/boom')
 const resources = require('../../gateway/resources')
 
+const webuiPath = '/ipfs/QmQNHd1suZTktPRhP7DD4nKWG46ZRSxkwHocycHVrK3dYW'
+
+const failAction = (request, h, err) => {
+  // match go-ipfs and return 404 without any details if path validation failed
+  if (err.name === 'ValidationError') throw Boom.notFound()
+  return err
+}
+
 module.exports = [
+  {
+    method: '*',
+    path: '/webui',
+    handler (request, h) {
+      return h.redirect(webuiPath)
+    }
+  },
   {
     method: '*',
     path: '/ipfs/{path*}',
     options: {
       handler: resources.gateway.handler,
       validate: {
         params: {
-          path: Joi.string().required()
-        }
+          path: Joi.string().regex(new RegExp(webuiPath.replace('/ipfs/', '^'))).required()
+        },
+        failAction
       },
       response: {
         ranges: false // disable built-in support, handler does it manually
@@ -24,9 +41,25 @@ module.exports = [
   },
   {
     method: '*',
-    path: '/webui',
-    handler (request, h) {
-      return h.redirect('/ipfs/QmQNHd1suZTktPRhP7DD4nKWG46ZRSxkwHocycHVrK3dYW')
+    path: '/ipns/{path*}',
+    options: {
+      handler: resources.gateway.handler,
+      validate: {
+        params: {
+          path: Joi.alternatives().try(
+            // be careful here, someone could register webui.ipfs.io.evil.com
+            Joi.string().regex(/^webui\.ipfs\.io\//), // ends with '/''
+            Joi.string().regex(/^webui\.ipfs\.io$/) // redirect will add '/'
+          ).required()
+        },
+        failAction
+      },
+      response: {
+        ranges: false // disable built-in support, handler does it manually
+      },
+      ext: {
+        onPostHandler: { method: resources.gateway.afterHandler }
+      }
     }
   }
 ]

test/http-api/inject/webui.js

@@ -0,0 +1,66 @@
+/* eslint-env mocha */
+'use strict'
+
+const expect = require('chai').expect
+
+module.exports = (http) => {
+  describe('Web UI', function () {
+    let api
+
+    before(() => {
+      api = http.api._httpApi._apiServers[0]
+    })
+
+    it('allow /webui', async () => {
+      const res = await api.inject({
+        method: 'GET',
+        url: '/webui'
+      })
+      // it should return a redirect
+      expect(res.statusCode).to.equal(302)
+      expect(res.headers.location).to.exist()
+    })
+
+    it('disallow /ipfs/ paths that are not webui', async () => {
+      const res = await api.inject({
+        method: 'GET',
+        url: '/ipfs/QmUNLLsPACCz1vLxQVkXqqLX5R1X345qqfHbsf67hvA3Nn' // empty dir
+      })
+      expect(res.statusCode).to.equal(404)
+    })
+
+    it('disallow /ipns/ paths that are not webui', async () => {
+      const res = await api.inject({
+        method: 'GET',
+        url: '/ipns/ipfs.io' // empty dir
+      })
+      expect(res.statusCode).to.equal(404)
+    })
+
+    /* DNSLink + fetching actual webui is too slow to include in the test :'-(
+    it('/ipns/webui.ipfs.io', async () => {
+      const res = await api.inject({
+        method: 'GET',
+        url: '/ipns/webui.ipfs.io'
+      })
+      expect(res.statusCode).to.equal(302)
+      expect(res.headers.location).to.exist()
+    })
+
+    it('/ipns/webui.ipfs.io/', async () => {
+      const res = await api.inject({
+        method: 'GET',
+        url: '/ipns/webui.ipfs.io/'
+      })
+      expect(res.statusCode).to.equal(200)
+    })
+    it('/ipns/ipfs.io/', async () => {
+      const res = await api.inject({
+        method: 'GET',
+        url: '/ipns/ipfs.io/'
+      })
+      expect(res.statusCode).to.equal(404)
+    })
+    */
+  })
+}