Move suggest code and rewrite tests (#2886)

The suggest code was an exception to our usual organization pattern. There was a service test, but it's not a service. The code would sometimes regress because it wasn't being tested all the time.

This makes them no longer run as service tests, which is good because they run as part of every build. Some of them are smaller-bracket tests which is good too, because it will make them easier to test, especially as this code grows.

I'd have liked to keep using frisby for the ones that make requests to the server, though I ran into some issues with sequencing of setup that I think will require upstream changes.

lib/suggest.js

@@ -1,161 +0,0 @@
-// Suggestion API
-//
-// eg. /$suggest/v1?url=https://github.com/badges/shields
-//
-// Tests for this endpoint are in services/suggest/suggest.spec.js. The
-// endpoint is called from frontend/components/suggestion-and-search.js.
-
-'use strict'
-
-const { URL } = require('url')
-const request = require('request')
-
-function twitterPage(url) {
-  if (url.protocol === null) {
-    return null
-  }
-
-  const schema = url.protocol.slice(0, -1)
-  const host = url.host
-  const path = url.pathname
-  return {
-    title: 'Twitter',
-    link: `https://twitter.com/intent/tweet?text=Wow:&url=${encodeURIComponent(
-      url.href
-    )}`,
-    path: `/twitter/url/${schema}/${host}${path}`,
-    queryParams: { style: 'social' },
-  }
-}
-
-function githubIssues(user, repo) {
-  const repoSlug = `${user}/${repo}`
-  return {
-    title: 'GitHub issues',
-    link: `https://github.com/${repoSlug}/issues`,
-    path: `/github/issues/${repoSlug}`,
-  }
-}
-
-function githubForks(user, repo) {
-  const repoSlug = `${user}/${repo}`
-  return {
-    title: 'GitHub forks',
-    link: `https://github.com/${repoSlug}/network`,
-    path: `/github/forks/${repoSlug}`,
-  }
-}
-
-function githubStars(user, repo) {
-  const repoSlug = `${user}/${repo}`
-  return {
-    title: 'GitHub stars',
-    link: `https://github.com/${repoSlug}/stargazers`,
-    path: `/github/stars/${repoSlug}`,
-  }
-}
-
-async function githubLicense(githubApiProvider, user, repo) {
-  const repoSlug = `${user}/${repo}`
-
-  let link = `https://github.com/${repoSlug}`
-
-  const { buffer } = await githubApiProvider.requestAsPromise(
-    request,
-    `/repos/${repoSlug}/license`
-  )
-  try {
-    const data = JSON.parse(buffer)
-    if ('html_url' in data) {
-      link = data.html_url
-    }
-  } catch (e) {}
-
-  return {
-    title: 'GitHub license',
-    path: `/github/license/${repoSlug}`,
-    link,
-  }
-}
-
-async function findSuggestions(githubApiProvider, url) {
-  let promises = []
-  if (url.hostname === 'github.com') {
-    const userRepo = url.pathname.slice(1).split('/')
-    const user = userRepo[0]
-    const repo = userRepo[1]
-    promises = promises.concat([
-      githubIssues(user, repo),
-      githubForks(user, repo),
-      githubStars(user, repo),
-      githubLicense(githubApiProvider, user, repo),
-    ])
-  }
-  promises.push(twitterPage(url))
-
-  const suggestions = await Promise.all(promises)
-
-  return suggestions.filter(b => b != null)
-}
-
-// data: {url}, JSON-serializable object.
-// end: function(json), with json of the form:
-//  - suggestions: list of objects of the form:
-//    - title: string
-//    - link: target as a string URL.
-//    - path: shields image URL path.
-//    - queryParams: Object containing query params (Optional)
-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. Chrome does not send an Origin header on same-origin
-    // requests, but Firefox does.
-    //
-    // It would be better to solve this problem using some well-tested
-    // middleware.
-    const origin = ask.req.headers.origin
-    if (origin) {
-      let host
-      try {
-        host = new URL(origin).hostname
-      } catch (e) {
-        ask.res.setHeader('Access-Control-Allow-Origin', 'null')
-        end({ err: 'Disallowed' })
-        return
-      }
-
-      if (host !== ask.req.headers.host) {
-        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
-        }
-      }
-    }
-
-    let url
-    try {
-      url = new URL(data.url)
-    } catch (e) {
-      end({ err: `${e}` })
-      return
-    }
-
-    findSuggestions(githubApiProvider, url)
-      // This interacts with callback code and can't use async/await.
-      // eslint-disable-next-line promise/prefer-await-to-then
-      .then(suggestions => {
-        end({ suggestions })
-      })
-      .catch(err => {
-        end({ suggestions: [], err })
-      })
-  })
-}
-
-module.exports = {
-  setRoutes,
-}