From db73c56eca625ce9647ae11826146717b9fd57da Mon Sep 17 00:00:00 2001
From: Brian Dennis <hi@briandennis.io>
Date: Tue, 19 Sep 2017 21:57:18 -0500
Subject: [PATCH] Add notification of Twitter rate limiting (#13)

* add rate limiting detection to handler

* alert user on rate limit error

* Update api.js

* Add morphmorph dep
---
 handlers/twitter.js | 15 +++++++++++++--
 lib/api.js          | 11 +++++++++++
 package.json        |  1 +
 yarn.lock           |  4 ++++
 4 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/handlers/twitter.js b/handlers/twitter.js
index 807be1e..0d15e0b 100644
--- a/handlers/twitter.js
+++ b/handlers/twitter.js
@@ -1,4 +1,7 @@
 const Twitter = require('twitter')
+const morph = require('morphmorph')
+
+const RATE_LIMIT_CODE = 420
 
 const client = new Twitter({
   consumer_key: process.env.TWITTER_CONSUMER_KEY,
@@ -9,11 +12,19 @@ const client = new Twitter({
 
 const uploadImage = (data) => client.post('media/upload', { media_data: data })
 const uploadTweet = (media) => client.post('statuses/update', { status: 'Carbon Copy', media_ids: media.media_id_string })
-const extractImageUrl = (response) => response.entities.media[0].display_url
+const extractImageUrl = morph.get('entities.media.0.display_url')
+const extractErrorCode = morph.get('0.code')
 
 const respondSuccess = (res, url) => res.json({ url })
 const respondFail = (res, err) => {
-  console.error(`Error: ${err.message || err}`)
+  const errorCode = extractErrorCode(err)
+
+  // check for rate limit
+  if (errorCode === RATE_LIMIT_CODE) {
+    return res.status(420).send()
+  }
+
+  console.error(`Error: ${errorCode || err.message}`)
   res.status(500).send()
 }
 
diff --git a/lib/api.js b/lib/api.js
index c4d1f89..d98ca3c 100644
--- a/lib/api.js
+++ b/lib/api.js
@@ -1,6 +1,7 @@
 import axios from 'axios'
 
 const DOMAIN = process.browser ? document.location.origin : ''
+const RATE_LIMIT_CODE = 420
 
 const gistClient = axios.create({
   baseURL: 'https://api.github.com',
@@ -19,6 +20,7 @@ async function tweet (encodedImage) {
   .then(url => encodeURIComponent(`Built with #Carbon, by @dawn_labs ${url}`))
   .then(uri => `https://twitter.com/intent/tweet?text=${uri}`)
   .then(openTwitterUrl)
+  .catch(checkIfRateLimited)
 }
 
 const getGist = (id) => {
@@ -40,6 +42,15 @@ function openTwitterUrl (twitterUrl) {
   window.open(twitterUrl, 'twitter', opts)
 }
 
+function checkIfRateLimited (err) {
+  if (err.response.status === RATE_LIMIT_CODE) {
+    alert('Oh no! Looks like to many people are trying to tweet right now and we\'ve been rate limited. Try again soon or save and upload manually!')
+    return
+  }
+  
+  throw err
+}
+
 
 export default {
   getGist,
diff --git a/package.json b/package.json
index 181308d..88041a2 100644
--- a/package.json
+++ b/package.json
@@ -18,6 +18,7 @@
     "form-data": "^2.2.0",
     "highlight.js": "^9.12.0",
     "morgan": "^1.8.2",
+    "morphmorph": "0.0.2",
     "next": "^3.2.2",
     "react": "^15.6.1",
     "react-click-outside": "^2.3.1",
diff --git a/yarn.lock b/yarn.lock
index cbde3fb..1543eeb 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2407,6 +2407,10 @@ morgan@^1.8.2:
     on-finished "~2.3.0"
     on-headers "~1.0.1"
 
+morphmorph@0.0.2:
+  version "0.0.2"
+  resolved "https://registry.yarnpkg.com/morphmorph/-/morphmorph-0.0.2.tgz#b2401b5e976ca4f4e068b730145aa64634aaa689"
+
 ms@2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/ms/-/ms-2.0.0.tgz#5608aeadfc00be6c2901df5f9861788de0d597c8"