Merge pull request #165 from overleaf/ho-retry-url-downloads

add pipeUrlToFileWithRetry for file downloads

services/clsi/app/js/UrlCache.js

@@ -95,7 +95,7 @@ module.exports = UrlCache = {
         }
         if (needsDownloading) {
           logger.log({ url, lastModified }, 'downloading URL')
-          return UrlFetcher.pipeUrlToFile(
+          return UrlFetcher.pipeUrlToFileWithRetry(
             url,
             UrlCache._cacheFilePathForUrl(project_id, url),
             error => {

services/clsi/app/js/UrlFetcher.js

@@ -12,16 +12,23 @@
  * DS207: Consider shorter variations of null checks
  * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
  */
-let UrlFetcher
 const request = require('request').defaults({ jar: false })
 const fs = require('fs')
 const logger = require('logger-sharelatex')
 const settings = require('settings-sharelatex')
 const URL = require('url')
+const async = require('async')
 
 const oneMinute = 60 * 1000
 
 module.exports = UrlFetcher = {
+  pipeUrlToFileWithRetry(url, filePath, callback) {
+    const doDownload = function(cb) {
+      UrlFetcher.pipeUrlToFile(url, filePath, cb)
+    }
+    async.retry(3, doDownload, callback)
+  },
+
   pipeUrlToFile(url, filePath, _callback) {
     if (_callback == null) {
       _callback = function(error) {}

services/clsi/test/acceptance/js/UrlCachingTests.js

@@ -11,7 +11,6 @@
  * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
  */
 const Client = require('./helpers/Client')
-const request = require('request')
 require('chai').should()
 const sinon = require('sinon')
 const ClsiApp = require('./helpers/ClsiApp')

services/clsi/test/unit/js/UrlCacheTests.js

@@ -160,7 +160,7 @@ describe('UrlCache', function() {
 
   describe('_ensureUrlIsInCache', function() {
     beforeEach(function() {
-      this.UrlFetcher.pipeUrlToFile = sinon.stub().callsArg(2)
+      this.UrlFetcher.pipeUrlToFileWithRetry = sinon.stub().callsArg(2)
       return (this.UrlCache._updateOrCreateUrlDetails = sinon
         .stub()
         .callsArg(3))
@@ -190,7 +190,7 @@ describe('UrlCache', function() {
       })
 
       it('should download the URL to the cache file', function() {
-        return this.UrlFetcher.pipeUrlToFile
+        return this.UrlFetcher.pipeUrlToFileWithRetry
           .calledWith(
             this.url,
             this.UrlCache._cacheFilePathForUrl(this.project_id, this.url)
@@ -232,7 +232,7 @@ describe('UrlCache', function() {
       })
 
       it('should not download the URL to the cache file', function() {
-        return this.UrlFetcher.pipeUrlToFile.called.should.equal(false)
+        return this.UrlFetcher.pipeUrlToFileWithRetry.called.should.equal(false)
       })
 
       return it('should return the callback with the cache file path', function() {

services/clsi/test/unit/js/UrlFetcherTests.js

@@ -33,7 +33,42 @@ describe('UrlFetcher', function() {
       }
     }))
   })
+  describe('pipeUrlToFileWithRetry', function() {
+    this.beforeEach(function() {
+      this.UrlFetcher.pipeUrlToFile = sinon.stub()
+    })
 
+    it('should call pipeUrlToFile', function(done) {
+      this.UrlFetcher.pipeUrlToFile.callsArgWith(2)
+      this.UrlFetcher.pipeUrlToFileWithRetry(this.url, this.path, err => {
+        expect(err).to.equal(undefined)
+        this.UrlFetcher.pipeUrlToFile.called.should.equal(true)
+        done()
+      })
+    })
+
+    it('should call pipeUrlToFile multiple times on error', function(done) {
+      error = new Error("couldn't download file")
+      this.UrlFetcher.pipeUrlToFile.callsArgWith(2, error)
+      this.UrlFetcher.pipeUrlToFileWithRetry(this.url, this.path, err => {
+        expect(err).to.equal(error)
+        this.UrlFetcher.pipeUrlToFile.callCount.should.equal(3)
+        done()
+      })
+    })
+
+    it('should call pipeUrlToFile twice if only 1 error', function(done) {
+      this.UrlFetcher.pipeUrlToFile.onCall(0).callsArgWith(2, 'error')
+      this.UrlFetcher.pipeUrlToFile.onCall(1).callsArgWith(2)
+      this.UrlFetcher.pipeUrlToFileWithRetry(this.url, this.path, err => {
+        expect(err).to.equal(undefined)
+        this.UrlFetcher.pipeUrlToFile.callCount.should.equal(2)
+        done()
+      })
+    })
+  })
+
+  describe('pipeUrlToFile', function() {
     it('should turn off the cookie jar in request', function() {
       return this.defaults.calledWith({ jar: false }).should.equal(true)
     })
@@ -145,7 +180,9 @@ describe('UrlFetcher', function() {
           this.callback.calledWith(sinon.match(Error)).should.equal(true)
 
           const message = this.callback.args[0][0].message
-        expect(message).to.include('URL returned non-success status code: 404')
+          expect(message).to.include(
+            'URL returned non-success status code: 404'
+          )
         })
       })
 
@@ -172,3 +209,4 @@ describe('UrlFetcher', function() {
       })
     })
   })
+})