Rework [suggest] code using async/await (#2029)

badges · Oct 31, 2018 · 07c5f47 · 07c5f47
1 parent cc84394
commit 07c5f47
Showing 1 changed file with 102 additions and 119 deletions.
diff --git a/lib/suggest.js b/lib/suggest.js
@@ -1,46 +1,83 @@
 // Suggestion API
 //
 // eg. /$suggest/v1?url=https://github.com/badges/shields
+//
+// Tests for this endpoint are in services/suggest/suggest.spec.js. The
+// endpoint is called from frontend/components/suggestion-and-search.js.
 
 'use strict'
 
 const nodeUrl = require('url')
 const request = require('request')
 
-// data: {url}, JSON-serializable object.
-// end: function(json), with json of the form:
-//  - badges: list of objects of the form:
-//    - link: target as a string URL.
-//    - badge: shields image URL.
-//    - name: string
-function suggest(allowedOrigin, githubApiProvider, data, end, ask) {
-  // The typical dev and production setups are cross-origin. However, in
-  // Heroku deploys and some self-hosted deploys these requests may come from
-  // the same host.
-  const origin = ask.req.headers.origin
-  if (origin) {
-    if (allowedOrigin.includes(origin)) {
-      ask.res.setHeader('Access-Control-Allow-Origin', origin)
-    } else {
-      ask.res.setHeader('Access-Control-Allow-Origin', 'null')
-      end({ err: 'Disallowed' })
-      return
-    }
+function twitterPage(url) {
+  if (url.protocol === null) {
+    return null
+  }
+
+  const schema = url.protocol.slice(0, -1)
+  const host = url.host
+  const path = url.path
+  return {
+    name: 'Twitter',
+    link: `https://twitter.com/intent/tweet?text=Wow:&url=${encodeURIComponent(
+      url.href
+    )}`,
+    badge: `https://img.shields.io/twitter/url/${schema}/${host}${path}.svg?style=social`,
+  }
+}
+
+function githubIssues(user, repo) {
+  const repoSlug = `${user}/${repo}`
+  return {
+    name: 'GitHub issues',
+    link: `https://github.com/${repoSlug}/issues`,
+    badge: `https://img.shields.io/github/issues/${repoSlug}.svg`,
   }
+}
 
-  let url
+function githubForks(user, repo) {
+  const repoSlug = `${user}/${repo}`
+  return {
+    name: 'GitHub forks',
+    link: `https://github.com/${repoSlug}/network`,
+    badge: `https://img.shields.io/github/forks/${repoSlug}.svg`,
+  }
+}
+
+function githubStars(user, repo) {
+  const repoSlug = `${user}/${repo}`
+  return {
+    name: 'GitHub stars',
+    link: `https://github.com/${repoSlug}/stargazers`,
+    badge: `https://img.shields.io/github/stars/${repoSlug}.svg`,
+  }
+}
+
+async function githubLicense(githubApiProvider, user, repo) {
+  const repoSlug = `${user}/${repo}`
+
+  let link = `https://github.com/${repoSlug}`
+
+  const { buffer } = await githubApiProvider.requestAsPromise(
+    request,
+    `/repos/${repoSlug}/license`
+  )
   try {
-    url = nodeUrl.parse(data.url)
-  } catch (e) {
-    end({ err: '' + e })
-    return
+    const data = JSON.parse(buffer)
+    if ('html_url' in data) {
+      link = data.html_url
+    }
+  } catch (e) {}
+
+  return {
+    name: 'GitHub license',
+    badge: `https://img.shields.io/github/license/${repoSlug}.svg`,
+    link,
   }
-  findSuggestions(githubApiProvider, url, end)
 }
 
-// url: string
-// cb: function({badges})
-function findSuggestions(githubApiProvider, url, cb) {
+async function findSuggestions(githubApiProvider, url) {
   let promises = []
   if (url.hostname === 'github.com') {
     const userRepo = url.pathname.slice(1).split('/')
@@ -54,106 +91,52 @@ function findSuggestions(githubApiProvider, url, cb) {
     ])
   }
   promises.push(twitterPage(url))
-  Promise.all(promises)
-    .then(badges => {
-      // eslint-disable-next-line standard/no-callback-literal
-      cb({
-        badges: badges.filter(b => b != null),
-      })
-    })
-    .catch(err => {
-      // eslint-disable-next-line standard/no-callback-literal
-      cb({ badges: [], err: err })
-    })
-}
 
-function twitterPage(url) {
-  if (url.protocol === null) {
-    return Promise.resolve(null)
-  }
-  const schema = url.protocol.slice(0, -1)
-  const host = url.host
-  const path = url.path
-  return Promise.resolve({
-    name: 'Twitter',
-    link:
-      'https://twitter.com/intent/tweet?text=Wow:&url=' +
-      encodeURIComponent(url.href),
-    badge:
-      'https://img.shields.io/twitter/url/' +
-      schema +
-      '/' +
-      host +
-      path +
-      '.svg?style=social',
-  })
-}
+  const suggestions = await Promise.all(promises)
 
-function githubIssues(user, repo) {
-  const userRepo = user + '/' + repo
-  return Promise.resolve({
-    name: 'GitHub issues',
-    link: 'https://github.com/' + userRepo + '/issues',
-    badge: 'https://img.shields.io/github/issues/' + userRepo + '.svg',
-  })
+  return suggestions.filter(b => b != null)
 }
 
-function githubForks(user, repo) {
-  const userRepo = user + '/' + repo
-  return Promise.resolve({
-    name: 'GitHub forks',
-    link: 'https://github.com/' + userRepo + '/network',
-    badge: 'https://img.shields.io/github/forks/' + userRepo + '.svg',
-  })
-}
-
-function githubStars(user, repo) {
-  const userRepo = user + '/' + repo
-  return Promise.resolve({
-    name: 'GitHub stars',
-    link: 'https://github.com/' + userRepo + '/stargazers',
-    badge: 'https://img.shields.io/github/stars/' + userRepo + '.svg',
-  })
-}
-
-function githubLicense(githubApiProvider, user, repo) {
-  return new Promise(resolve => {
-    const apiUrl = `/repos/${user}/${repo}/license`
-    githubApiProvider.request(request, apiUrl, {}, (err, res, buffer) => {
-      if (err !== null) {
-        resolve(null)
+// data: {url}, JSON-serializable object.
+// end: function(json), with json of the form:
+//  - badges: list of objects of the form:
+//    - link: target as a string URL.
+//    - badge: shields image URL.
+//    - name: string
+function setRoutes(allowedOrigin, githubApiProvider, server) {
+  server.ajax.on('suggest/v1', (data, end, ask) => {
+    // The typical dev and production setups are cross-origin. However, in
+    // Heroku deploys and some self-hosted deploys these requests may come from
+    // the same host.
+    const origin = ask.req.headers.origin
+    if (origin) {
+      if (allowedOrigin.includes(origin)) {
+        ask.res.setHeader('Access-Control-Allow-Origin', origin)
+      } else {
+        ask.res.setHeader('Access-Control-Allow-Origin', 'null')
+        end({ err: 'Disallowed' })
         return
       }
-      const defaultBadge = {
-        name: 'GitHub license',
-        link: `https://github.com/${user}/${repo}`,
-        badge: `https://img.shields.io/github/license/${user}/${repo}.svg`,
-      }
-      if (res.statusCode !== 200) {
-        resolve(defaultBadge)
-      }
-      try {
-        const data = JSON.parse(buffer)
-        if (data.html_url) {
-          defaultBadge.link = data.html_url
-          resolve(defaultBadge)
-        } else {
-          resolve(defaultBadge)
-        }
-      } catch (e) {
-        resolve(defaultBadge)
-      }
-    })
-  })
-}
+    }
 
-function setRoutes(allowedOrigin, githubApiProvider, server) {
-  server.ajax.on('suggest/v1', (data, end, ask) =>
-    suggest(allowedOrigin, githubApiProvider, data, end, ask)
-  )
+    let url
+    try {
+      url = nodeUrl.parse(data.url)
+    } catch (e) {
+      end({ err: '' + e })
+      return
+    }
+
+    findSuggestions(githubApiProvider, url)
+      .then(badges => {
+        end({ badges })
+      })
+      .catch(err => {
+        end({ badges: [], err })
+      })
+  })
 }
 
 module.exports = {
-  suggest,
   setRoutes,
 }