Identity link id system - handle empty response (prebid#5279)

* IdentityLinkIdSystem - handle empty response

* IdentityLinkIdSystem - add tests

* IdentityLinkIdSystem - rename describe in tests

modules/identityLinkIdSystem.js

@@ -73,7 +73,7 @@ function getEnvelope(url, callback) {
           utils.logError(error);
         }
       }
-      callback(responseObj.envelope);
+      callback((responseObj && responseObj.envelope) ? responseObj.envelope : '');
     },
     error: error => {
       utils.logError(`identityLink: ID fetch encountered an error`, error);

test/spec/modules/identityLinkIdSystem_spec.js

@@ -0,0 +1,92 @@
+import {identityLinkSubmodule} from 'modules/identityLinkIdSystem.js';
+import * as utils from 'src/utils.js';
+import {server} from 'test/mocks/xhr.js';
+
+const pid = '14';
+const defaultConfigParams = {pid: pid};
+const responseHeader = {'Content-Type': 'application/json'}
+
+describe('IdentityLinkId tests', function () {
+  let logErrorStub;
+
+  beforeEach(function () {
+    logErrorStub = sinon.stub(utils, 'logError');
+  });
+
+  afterEach(function () {
+    logErrorStub.restore();
+  });
+
+  it('should log an error if no configParams were passed when getId', function () {
+    identityLinkSubmodule.getId();
+    expect(logErrorStub.calledOnce).to.be.true;
+  });
+
+  it('should log an error if pid configParam was not passed when getId', function () {
+    identityLinkSubmodule.getId({});
+    expect(logErrorStub.calledOnce).to.be.true;
+  });
+
+  it('should call the LiveRamp envelope endpoint', function () {
+    let callBackSpy = sinon.spy();
+    let submoduleCallback = identityLinkSubmodule.getId(defaultConfigParams).callback;
+    submoduleCallback(callBackSpy);
+    let request = server.requests[0];
+    expect(request.url).to.be.eq('https://api.rlcdn.com/api/identity/envelope?pid=14');
+    request.respond(
+      200,
+      responseHeader,
+      JSON.stringify({})
+    );
+    expect(callBackSpy.calledOnce).to.be.true;
+  });
+
+  it('should call the LiveRamp envelope endpoint with consent string', function () {
+    let callBackSpy = sinon.spy();
+    let consentData = {
+      gdprApplies: true,
+      consentString: 'BOkIpDSOkIpDSADABAENCc-AAAApOAFAAMAAsAMIAcAA_g'
+    };
+    let submoduleCallback = identityLinkSubmodule.getId(defaultConfigParams, consentData).callback;
+    submoduleCallback(callBackSpy);
+    let request = server.requests[0];
+    expect(request.url).to.be.eq('https://api.rlcdn.com/api/identity/envelope?pid=14&ct=1&cv=BOkIpDSOkIpDSADABAENCc-AAAApOAFAAMAAsAMIAcAA_g');
+    request.respond(
+      200,
+      responseHeader,
+      JSON.stringify({})
+    );
+    expect(callBackSpy.calledOnce).to.be.true;
+  });
+
+  it('should not throw Uncaught TypeError when envelope endpoint returns empty response', function () {
+    let callBackSpy = sinon.spy();
+    let submoduleCallback = identityLinkSubmodule.getId(defaultConfigParams).callback;
+    submoduleCallback(callBackSpy);
+    let request = server.requests[0];
+    expect(request.url).to.be.eq('https://api.rlcdn.com/api/identity/envelope?pid=14');
+    request.respond(
+      204,
+      responseHeader,
+      ''
+    );
+    expect(callBackSpy.calledOnce).to.be.true;
+    expect(request.response).to.equal('');
+    expect(logErrorStub.calledOnce).to.not.be.true;
+  });
+
+  it('should log an error and continue to callback if ajax request errors', function () {
+    let callBackSpy = sinon.spy();
+    let submoduleCallback = identityLinkSubmodule.getId(defaultConfigParams).callback;
+    submoduleCallback(callBackSpy);
+    let request = server.requests[0];
+    expect(request.url).to.be.eq('https://api.rlcdn.com/api/identity/envelope?pid=14');
+    request.respond(
+      503,
+      responseHeader,
+      'Unavailable'
+    );
+    expect(logErrorStub.calledOnce).to.be.true;
+    expect(callBackSpy.calledOnce).to.be.true;
+  });
+});