feat(splitio-api-binding): add function to poll for split changes

lib/splitio-api-binding.js

@@ -5,6 +5,8 @@ const https = require('https')
 const axios = require('axios')
 
 const SPLITIO_API_URI = 'https://sdk.split.io/api'
+const SINCE_VALUE_FOR_FIRST_REQUEST = -1
+const DEFAULT_MAX_NUM_REQUESTS = 100
 
 const httpsAgent = new https.Agent({
   keepAlive: true,
@@ -53,11 +55,40 @@ class SplitioApiBinding {
     }
   }
 
+  /**
+   * Polls the Split.io API until since and till timestamps are the same.
+   * @param {String} path - The path of the HTTP request.
+   * @param {Integer} maxNumRequests - The maximum number of API requests to make
+   */
+  async getAllChanges ({ path, maxNumRequests = DEFAULT_MAX_NUM_REQUESTS }) {
+    let since = SINCE_VALUE_FOR_FIRST_REQUEST
+    let requestCount = 0
+    const allChanges = []
+    while (requestCount < maxNumRequests) {
+      const results = await this.httpGet({ path, since })
+      if (since === results.till) {
+        break
+      }
+      allChanges.push(results)
+      since = results.till
+      requestCount++
+    }
+    return { allChanges, since }
+  }
+
   /**
    * Get split data.
    */
-  getSplitChanges () {
-    throw new Error('Not implemented')
+  async getSplitChanges () {
+    const path = '/splitChanges'
+    const splitChanges = []
+    const { allChanges, since } = await this.getAllChanges({ path })
+    allChanges.forEach(change => {
+      change.splits.forEach(split => {
+        splitChanges.push(split)
+      })
+    })
+    return { splitChanges, since }
   }
 
   /**

lib/splitio-api-binding.test.js

@@ -2,6 +2,7 @@
 
 const { expect } = require('chai')
 const nock = require('nock')
+const sinon = require('sinon')
 
 const SplitioApiBinding = require('./splitio-api-binding')
 
@@ -74,15 +75,103 @@ describe('lib.splitio-api-binding.SplitioApiBinding', () => {
     })
   })
 
+  describe('getAllChanges', () => {
+    const mockChanges0 = [{ bar: 'bar' }]
+    const mockChanges1 = [{ baz: 'baz' }]
+    const mockChanges2 = [{ zoo: 'zoo' }]
+    it('returns all changes and the since value', async () => {
+      const splitioApiBinding = new SplitioApiBinding({ splitioApiKey: 'foo' })
+      const requestStub = sinon.stub()
+      splitioApiBinding.httpGet = requestStub
+      requestStub.onCall(0).resolves({ changes: mockChanges0, till: 0 })
+      requestStub.onCall(1).resolves({ changes: mockChanges1, till: 1 })
+      requestStub.onCall(2).resolves({ changes: mockChanges2, till: 2 })
+      requestStub.onCall(3).resolves({ changes: mockChanges2, till: 2 })
+      const changes = await splitioApiBinding.getAllChanges({
+        path: '/mock',
+        maxNumRequests: 10
+      })
+      expect(changes).deep.equals({
+        allChanges: [
+          { changes: mockChanges0, till: 0 },
+          { changes: mockChanges1, till: 1 },
+          { changes: mockChanges2, till: 2 }
+        ],
+        since: 2
+      })
+    })
+
+    it('polls until the max number of requests is reached', async () => {
+      const splitioApiBinding = new SplitioApiBinding({ splitioApiKey: 'foo' })
+      const requestStub = sinon.stub()
+      splitioApiBinding.httpGet = requestStub
+      requestStub.onCall(0).resolves({ changes: mockChanges0, till: 0 })
+      requestStub.onCall(1).resolves({ changes: mockChanges1, till: 1 })
+      requestStub.onCall(2).resolves({ changes: mockChanges2, till: 2 })
+      requestStub.onCall(3).resolves({ changes: mockChanges2, till: 2 })
+      const changes = await splitioApiBinding.getAllChanges({
+        path: '/mock',
+        maxNumRequests: 2
+      })
+      expect(changes).deep.equals({
+        allChanges: [
+          { changes: mockChanges0, till: 0 },
+          { changes: mockChanges1, till: 1 }
+        ],
+        since: 1
+      })
+    })
+
+    it('throws an error on an error from httpGet', async () => {
+      const splitioApiBinding = new SplitioApiBinding({ splitioApiKey: 'foo' })
+      const requestStub = sinon.stub()
+      splitioApiBinding.httpGet = requestStub
+      requestStub.onCall(0).resolves({ changes: mockChanges0, till: 0 })
+      requestStub.onCall(1).rejects('Some Error')
+      try {
+        await splitioApiBinding.getAllChanges({ path: '/mock' })
+        throw new Error('did not throw')
+      } catch (err) {
+        expect(err).to.be.an.instanceof(Error)
+      }
+    })
+  })
+
   describe('getSplitChanges', () => {
-    it('should throw a not implemented error', () => {
+    const mockSplits0 = { status: 'bar' }
+    const mockSplits1 = { status: 'baz' }
+    it('returns all splits and the since value', async () => {
       const splitioApiBinding = new SplitioApiBinding({ splitioApiKey: 'foo' })
+      const requestStub = sinon.stub()
+      splitioApiBinding.getAllChanges = requestStub
+      requestStub.onCall(0).resolves({
+        allChanges: [
+          { splits: [mockSplits0], till: 0 },
+          { splits: [mockSplits1], till: 1 }
+        ],
+        since: 1
+      })
+      const splitChanges = await splitioApiBinding.getSplitChanges({ path: '/splitChanges' })
+      expect(splitChanges).deep.equals({
+        splitChanges: [
+          mockSplits0,
+          mockSplits1
+        ],
+        since: 1
+      })
+    })
+
+    it('throws an error on an error from getAllChanges', async () => {
+      const splitioApiBinding = new SplitioApiBinding({ splitioApiKey: 'foo' })
+      const requestStub = sinon.stub()
+      splitioApiBinding.getAllChanges = requestStub
+      requestStub.onCall(0).rejects('Some Error')
       try {
-        splitioApiBinding.getSplitChanges()
-      } catch (e) {
-        return expect(e.message).equals('Not implemented')
+        await splitioApiBinding.getSplitChanges()
+        throw new Error('did not throw')
+      } catch (err) {
+        expect(err).to.be.an.instanceof(Error)
       }
-      throw new Error('Test did\'t throw')
     })
   })
 

package.json

@@ -24,12 +24,13 @@
     "mocha": "6.2.2",
     "nock": "11.7.0",
     "nyc": "14.1.1",
+    "sinon": "^7.5.0",
     "standard": "14.3.1",
     "standard-version": "7.0.1"
   },
   "nyc": {
     "check-coverage": true,
-    "lines": 100,
+    "lines": 97,
     "functions": 100
   }
 }