Dynamic Call Center with Node.js and Express

In this tutorial we will show how to automate the routing of calls from customers to your support agents. In this example customers would select a product, then be connected to a specialist for that product. If no one is available our customer's number will be saved so that our agent can call them back.

What the application does

At a high level, the application does the following:

Configure a workspace using the Twilio TaskRouter REST API.
Listen for incoming calls and let the user select a product with the dial pad.
Create a Task with the selected product and let TaskRouter handle it.
Store missed calls so agents can return the call to customers.
Redirect users to a voice mail when no one answers the call.
Allow agents to change their status (Available/Offline) via SMS.

Configure the Workspace

In order to instruct TaskRouter to handle the Tasks, we need to configure a Workspace. We can do this in the TaskRouter Console or programmatically using the TaskRouter REST API.

In this Node.js application we'll do this setup when we start up the app.

A Workspace is the container element for any TaskRouter application. The elements are:

Tasks - Represents a customer trying to contact an agent
Workers - The agents responsible for handling Tasks
Task Queues - Holds Tasks to be consumed by a set of Workers
Workflows - Responsible for placing Tasks into Task Queues
Activities - Possible states of a Worker. Eg: idle, offline, busy

To build a client for this API, you need a TWILIO_ACCOUNT_SID, TWILIO_API_KEY, and TWILIO_API_SECRET. Find your Account SID in the Twilio Console or the legacy Console and create an API key. The function initClient configures and returns a TaskRouterClient, which the Twilio Node.js library provides.

Create, Setup and Configure the Workspace

lib/workspace.js

1'use strict';
2
3var twilio = require('twilio');
4var find = require('lodash/find');
5var map = require('lodash/map');
6var difference = require('lodash/difference');
7var WORKSPACE_NAME = 'TaskRouter Node Workspace';
8var HOST = process.env.HOST;
9var EVENT_CALLBACK = `${HOST}/events`;
10var ACCOUNT_SID = process.env.TWILIO_ACCOUNT_SID;
11var API_KEY = process.env.TWILIO_API_KEY;
12var API_SECRET = process.env.TWILIO_API_SECRET;
13
14module.exports = function() {
15  function initClient(existingWorkspaceSid) {
16    if (!existingWorkspaceSid) {
17      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID }).taskrouter.v1.workspaces;
18    } else {
19      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID })
20      .taskrouter.v1.workspaces(existingWorkspaceSid);
21    }
22  }
23
24  function createWorker(opts) {
25    var ctx = this;
26
27    return this.client.activities.list({friendlyName: 'Idle'})
28    .then(function(idleActivity) {
29      return ctx.client.workers.create({
30        friendlyName: opts.name,
31        attributes: JSON.stringify({
32          'products': opts.products,
33          'contact_uri': opts.phoneNumber,
34        }),
35        activitySid: idleActivity.sid,
36      });
37    });
38  }
39
40  function createWorkflow() {
41    var ctx = this;
42    var config = this.createWorkflowConfig();
43
44    return ctx.client.workflows
45      .create({
46        friendlyName: 'Sales',
47        assignmentCallbackUrl: HOST + '/call/assignment',
48        fallbackAssignmentCallbackUrl: HOST + '/call/assignment',
49        taskReservationTimeout: 15,
50        configuration: config,
51      })
52      .then(function(workflow) {
53        return ctx.client.activities.list()
54          .then(function(activities) {
55            var idleActivity = find(activities, {friendlyName: 'Idle'});
56            var offlineActivity = find(activities, {friendlyName: 'Offline'});
57
58            return {
59              workflowSid: workflow.sid,
60              activities: {
61                idle: idleActivity.sid,
62                offline: offlineActivity.sid,
63              },
64              workspaceSid: ctx.client._solution.sid,
65            };
66          });
67      });
68  }
69
70  function createTaskQueues() {
71    var ctx = this;
72    return this.client.activities.list()
73      .then(function(activities) {
74        var busyActivity = find(activities, {friendlyName: 'Busy'});
75        var reservedActivity = find(activities, {friendlyName: 'Reserved'});
76
77        return Promise.all([
78          ctx.client.taskQueues.create({
79            friendlyName: 'SMS',
80            targetWorkers: 'products HAS "ProgrammableSMS"',
81            assignmentActivitySid: busyActivity.sid,
82            reservationActivitySid: reservedActivity.sid,
83          }),
84          ctx.client.taskQueues.create({
85            friendlyName: 'Voice',
86            targetWorkers: 'products HAS "ProgrammableVoice"',
87            assignmentActivitySid: busyActivity.sid,
88            reservationActivitySid: reservedActivity.sid,
89          }),
90          ctx.client.taskQueues.create({
91            friendlyName: 'Default',
92            targetWorkers: '1==1',
93            assignmentActivitySid: busyActivity.sid,
94            reservationActivitySid: reservedActivity.sid,
95          }),
96        ])
97        .then(function(queues) {
98          ctx.queues = queues;
99        });
100      });
101  }
102
103  function createWorkers() {
104    var ctx = this;
105
106    return Promise.all([
107      ctx.createWorker({
108        name: 'Bob',
109        phoneNumber: process.env.BOB_NUMBER,
110        products: ['ProgrammableSMS'],
111      }),
112      ctx.createWorker({
113        name: 'Alice',
114        phoneNumber: process.env.ALICE_NUMBER,
115        products: ['ProgrammableVoice'],
116      })
117    ])
118    .then(function(workers) {
119      var bobWorker = workers[0];
120      var aliceWorker = workers[1];
121      var workerInfo = {};
122
123      workerInfo[process.env.ALICE_NUMBER] = aliceWorker.sid;
124      workerInfo[process.env.BOB_NUMBER] = bobWorker.sid;
125
126      return workerInfo;
127    });
128  }
129
130  function createWorkflowActivities() {
131    var ctx = this;
132    var activityNames = ['Idle', 'Busy', 'Offline', 'Reserved'];
133
134    return ctx.client.activities.list()
135      .then(function(activities) {
136        var existingActivities = map(activities, 'friendlyName');
137
138        var missingActivities = difference(activityNames, existingActivities);
139
140        var newActivities = map(missingActivities, function(friendlyName) {
141          return ctx.client.activities
142            .create({
143              friendlyName: friendlyName,
144              available: 'true'
145            });
146        });
147
148        return Promise.all(newActivities);
149      })
150      .then(function() {
151        return ctx.client.activities.list();
152      });
153  }
154
155  function createWorkflowConfig() {
156    var queues = this.queues;
157
158    if (!queues) {
159      throw new Error('Queues must be initialized.');
160    }
161
162    var defaultTarget = {
163      queue: find(queues, {friendlyName: 'Default'}).sid,
164      timeout: 30,
165      priority: 1,
166    };
167
168    var smsTarget = {
169      queue: find(queues, {friendlyName: 'SMS'}).sid,
170      timeout: 30,
171      priority: 5,
172    };
173
174    var voiceTarget = {
175      queue: find(queues, {friendlyName: 'Voice'}).sid,
176      timeout: 30,
177      priority: 5,
178    };
179
180    var rules = [
181      {
182        expression: 'selected_product=="ProgrammableSMS"',
183        targets: [smsTarget, defaultTarget],
184        timeout: 30,
185      },
186      {
187        expression: 'selected_product=="ProgrammableVoice"',
188        targets: [voiceTarget, defaultTarget],
189        timeout: 30,
190      },
191    ];
192
193    var config = {
194      task_routing: {
195        filters: rules,
196        default_filter: defaultTarget,
197      },
198    };
199
200    return JSON.stringify(config);
201  }
202
203  function setup() {
204    var ctx = this;
205
206    ctx.initClient();
207
208    return this.initWorkspace()
209      .then(createWorkflowActivities.bind(ctx))
210      .then(createTaskQueues.bind(ctx))
211      .then(createWorkflow.bind(ctx))
212      .then(function(workspaceInfo) {
213        return ctx.createWorkers()
214        .then(function(workerInfo) {
215          return [workerInfo, workspaceInfo];
216        });
217      });
218  }
219
220  function findByFriendlyName(friendlyName) {
221    var client = this.client;
222
223    return client.list()
224      .then(function (data) {
225        return find(data, {friendlyName: friendlyName});
226      });
227  }
228
229  function deleteByFriendlyName(friendlyName) {
230    var ctx = this;
231
232    return this.findByFriendlyName(friendlyName)
233      .then(function(workspace) {
234        if (workspace.remove) {
235          return workspace.remove();
236        }
237      });
238  }
239
240  function createWorkspace() {
241    return this.client.create({
242      friendlyName: WORKSPACE_NAME,
243      EVENT_CALLBACKUrl: EVENT_CALLBACK,
244    });
245  }
246
247  function initWorkspace() {
248    var ctx = this;
249    var client = this.client;
250
251    return ctx.findByFriendlyName(WORKSPACE_NAME)
252      .then(function(workspace) {
253        var newWorkspace;
254
255        if (workspace) {
256         newWorkspace = ctx.deleteByFriendlyName(WORKSPACE_NAME)
257                   .then(createWorkspace.bind(ctx));
258        } else {
259         newWorkspace = ctx.createWorkspace();
260        }
261
262        return newWorkspace;
263      })
264      .then(function(workspace) {
265        ctx.initClient(workspace.sid);
266
267        return workspace;
268      });
269  }
270
271  return {
272    createTaskQueues: createTaskQueues,
273    createWorker: createWorker,
274    createWorkers: createWorkers,
275    createWorkflow: createWorkflow,
276    createWorkflowActivities: createWorkflowActivities,
277    createWorkflowConfig: createWorkflowConfig,
278    createWorkspace: createWorkspace,
279    deleteByFriendlyName: deleteByFriendlyName,
280    findByFriendlyName: findByFriendlyName,
281    initClient: initClient,
282    initWorkspace: initWorkspace,
283    setup: setup,
284  };
285};

Now let's look in more detail at all the steps, starting with the creation of the workspace itself.

Create a Workspace

Before creating a workspace, we need to delete any others with the same friendlyName as the one we are trying to create. In order to create a workspace we need to provide a friendlyName and a eventCallbackUrl where a request will be made every time an event is triggered in our workspace.

Create Workspace

lib/workspace.js

1'use strict';
2
3var twilio = require('twilio');
4var find = require('lodash/find');
5var map = require('lodash/map');
6var difference = require('lodash/difference');
7var WORKSPACE_NAME = 'TaskRouter Node Workspace';
8var HOST = process.env.HOST;
9var EVENT_CALLBACK = `${HOST}/events`;
10var ACCOUNT_SID = process.env.TWILIO_ACCOUNT_SID;
11var API_KEY = process.env.TWILIO_API_KEY;
12var API_SECRET = process.env.TWILIO_API_SECRET;
13
14module.exports = function() {
15  function initClient(existingWorkspaceSid) {
16    if (!existingWorkspaceSid) {
17      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID }).taskrouter.v1.workspaces;
18    } else {
19      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID })
20      .taskrouter.v1.workspaces(existingWorkspaceSid);
21    }
22  }
23
24  function createWorker(opts) {
25    var ctx = this;
26
27    return this.client.activities.list({friendlyName: 'Idle'})
28    .then(function(idleActivity) {
29      return ctx.client.workers.create({
30        friendlyName: opts.name,
31        attributes: JSON.stringify({
32          'products': opts.products,
33          'contact_uri': opts.phoneNumber,
34        }),
35        activitySid: idleActivity.sid,
36      });
37    });
38  }
39
40  function createWorkflow() {
41    var ctx = this;
42    var config = this.createWorkflowConfig();
43
44    return ctx.client.workflows
45      .create({
46        friendlyName: 'Sales',
47        assignmentCallbackUrl: HOST + '/call/assignment',
48        fallbackAssignmentCallbackUrl: HOST + '/call/assignment',
49        taskReservationTimeout: 15,
50        configuration: config,
51      })
52      .then(function(workflow) {
53        return ctx.client.activities.list()
54          .then(function(activities) {
55            var idleActivity = find(activities, {friendlyName: 'Idle'});
56            var offlineActivity = find(activities, {friendlyName: 'Offline'});
57
58            return {
59              workflowSid: workflow.sid,
60              activities: {
61                idle: idleActivity.sid,
62                offline: offlineActivity.sid,
63              },
64              workspaceSid: ctx.client._solution.sid,
65            };
66          });
67      });
68  }
69
70  function createTaskQueues() {
71    var ctx = this;
72    return this.client.activities.list()
73      .then(function(activities) {
74        var busyActivity = find(activities, {friendlyName: 'Busy'});
75        var reservedActivity = find(activities, {friendlyName: 'Reserved'});
76
77        return Promise.all([
78          ctx.client.taskQueues.create({
79            friendlyName: 'SMS',
80            targetWorkers: 'products HAS "ProgrammableSMS"',
81            assignmentActivitySid: busyActivity.sid,
82            reservationActivitySid: reservedActivity.sid,
83          }),
84          ctx.client.taskQueues.create({
85            friendlyName: 'Voice',
86            targetWorkers: 'products HAS "ProgrammableVoice"',
87            assignmentActivitySid: busyActivity.sid,
88            reservationActivitySid: reservedActivity.sid,
89          }),
90          ctx.client.taskQueues.create({
91            friendlyName: 'Default',
92            targetWorkers: '1==1',
93            assignmentActivitySid: busyActivity.sid,
94            reservationActivitySid: reservedActivity.sid,
95          }),
96        ])
97        .then(function(queues) {
98          ctx.queues = queues;
99        });
100      });
101  }
102
103  function createWorkers() {
104    var ctx = this;
105
106    return Promise.all([
107      ctx.createWorker({
108        name: 'Bob',
109        phoneNumber: process.env.BOB_NUMBER,
110        products: ['ProgrammableSMS'],
111      }),
112      ctx.createWorker({
113        name: 'Alice',
114        phoneNumber: process.env.ALICE_NUMBER,
115        products: ['ProgrammableVoice'],
116      })
117    ])
118    .then(function(workers) {
119      var bobWorker = workers[0];
120      var aliceWorker = workers[1];
121      var workerInfo = {};
122
123      workerInfo[process.env.ALICE_NUMBER] = aliceWorker.sid;
124      workerInfo[process.env.BOB_NUMBER] = bobWorker.sid;
125
126      return workerInfo;
127    });
128  }
129
130  function createWorkflowActivities() {
131    var ctx = this;
132    var activityNames = ['Idle', 'Busy', 'Offline', 'Reserved'];
133
134    return ctx.client.activities.list()
135      .then(function(activities) {
136        var existingActivities = map(activities, 'friendlyName');
137
138        var missingActivities = difference(activityNames, existingActivities);
139
140        var newActivities = map(missingActivities, function(friendlyName) {
141          return ctx.client.activities
142            .create({
143              friendlyName: friendlyName,
144              available: 'true'
145            });
146        });
147
148        return Promise.all(newActivities);
149      })
150      .then(function() {
151        return ctx.client.activities.list();
152      });
153  }
154
155  function createWorkflowConfig() {
156    var queues = this.queues;
157
158    if (!queues) {
159      throw new Error('Queues must be initialized.');
160    }
161
162    var defaultTarget = {
163      queue: find(queues, {friendlyName: 'Default'}).sid,
164      timeout: 30,
165      priority: 1,
166    };
167
168    var smsTarget = {
169      queue: find(queues, {friendlyName: 'SMS'}).sid,
170      timeout: 30,
171      priority: 5,
172    };
173
174    var voiceTarget = {
175      queue: find(queues, {friendlyName: 'Voice'}).sid,
176      timeout: 30,
177      priority: 5,
178    };
179
180    var rules = [
181      {
182        expression: 'selected_product=="ProgrammableSMS"',
183        targets: [smsTarget, defaultTarget],
184        timeout: 30,
185      },
186      {
187        expression: 'selected_product=="ProgrammableVoice"',
188        targets: [voiceTarget, defaultTarget],
189        timeout: 30,
190      },
191    ];
192
193    var config = {
194      task_routing: {
195        filters: rules,
196        default_filter: defaultTarget,
197      },
198    };
199
200    return JSON.stringify(config);
201  }
202
203  function setup() {
204    var ctx = this;
205
206    ctx.initClient();
207
208    return this.initWorkspace()
209      .then(createWorkflowActivities.bind(ctx))
210      .then(createTaskQueues.bind(ctx))
211      .then(createWorkflow.bind(ctx))
212      .then(function(workspaceInfo) {
213        return ctx.createWorkers()
214        .then(function(workerInfo) {
215          return [workerInfo, workspaceInfo];
216        });
217      });
218  }
219
220  function findByFriendlyName(friendlyName) {
221    var client = this.client;
222
223    return client.list()
224      .then(function (data) {
225        return find(data, {friendlyName: friendlyName});
226      });
227  }
228
229  function deleteByFriendlyName(friendlyName) {
230    var ctx = this;
231
232    return this.findByFriendlyName(friendlyName)
233      .then(function(workspace) {
234        if (workspace.remove) {
235          return workspace.remove();
236        }
237      });
238  }
239
240  function createWorkspace() {
241    return this.client.create({
242      friendlyName: WORKSPACE_NAME,
243      EVENT_CALLBACKUrl: EVENT_CALLBACK,
244    });
245  }
246
247  function initWorkspace() {
248    var ctx = this;
249    var client = this.client;
250
251    return ctx.findByFriendlyName(WORKSPACE_NAME)
252      .then(function(workspace) {
253        var newWorkspace;
254
255        if (workspace) {
256         newWorkspace = ctx.deleteByFriendlyName(WORKSPACE_NAME)
257                   .then(createWorkspace.bind(ctx));
258        } else {
259         newWorkspace = ctx.createWorkspace();
260        }
261
262        return newWorkspace;
263      })
264      .then(function(workspace) {
265        ctx.initClient(workspace.sid);
266
267        return workspace;
268      });
269  }
270
271  return {
272    createTaskQueues: createTaskQueues,
273    createWorker: createWorker,
274    createWorkers: createWorkers,
275    createWorkflow: createWorkflow,
276    createWorkflowActivities: createWorkflowActivities,
277    createWorkflowConfig: createWorkflowConfig,
278    createWorkspace: createWorkspace,
279    deleteByFriendlyName: deleteByFriendlyName,
280    findByFriendlyName: findByFriendlyName,
281    initClient: initClient,
282    initWorkspace: initWorkspace,
283    setup: setup,
284  };
285};

We have a brand new workspace, now we need workers. Let's create them on the next step.

Create the Workers

We'll create two workers: Bob and Alice. They each have two attributes: contact_uri a phone number and products, a list of products each worker is specialized in. We also need to specify an activitySid and a name for each worker. The selected activity will define the status of the worker.

A set of default activities is created with your workspace. We use the Idle activity to make a worker available for incoming calls.

Create Workers

lib/workspace.js

1'use strict';
2
3var twilio = require('twilio');
4var find = require('lodash/find');
5var map = require('lodash/map');
6var difference = require('lodash/difference');
7var WORKSPACE_NAME = 'TaskRouter Node Workspace';
8var HOST = process.env.HOST;
9var EVENT_CALLBACK = `${HOST}/events`;
10var ACCOUNT_SID = process.env.TWILIO_ACCOUNT_SID;
11var API_KEY = process.env.TWILIO_API_KEY;
12var API_SECRET = process.env.TWILIO_API_SECRET;
13
14module.exports = function() {
15  function initClient(existingWorkspaceSid) {
16    if (!existingWorkspaceSid) {
17      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID }).taskrouter.v1.workspaces;
18    } else {
19      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID })
20      .taskrouter.v1.workspaces(existingWorkspaceSid);
21    }
22  }
23
24  function createWorker(opts) {
25    var ctx = this;
26
27    return this.client.activities.list({friendlyName: 'Idle'})
28    .then(function(idleActivity) {
29      return ctx.client.workers.create({
30        friendlyName: opts.name,
31        attributes: JSON.stringify({
32          'products': opts.products,
33          'contact_uri': opts.phoneNumber,
34        }),
35        activitySid: idleActivity.sid,
36      });
37    });
38  }
39
40  function createWorkflow() {
41    var ctx = this;
42    var config = this.createWorkflowConfig();
43
44    return ctx.client.workflows
45      .create({
46        friendlyName: 'Sales',
47        assignmentCallbackUrl: HOST + '/call/assignment',
48        fallbackAssignmentCallbackUrl: HOST + '/call/assignment',
49        taskReservationTimeout: 15,
50        configuration: config,
51      })
52      .then(function(workflow) {
53        return ctx.client.activities.list()
54          .then(function(activities) {
55            var idleActivity = find(activities, {friendlyName: 'Idle'});
56            var offlineActivity = find(activities, {friendlyName: 'Offline'});
57
58            return {
59              workflowSid: workflow.sid,
60              activities: {
61                idle: idleActivity.sid,
62                offline: offlineActivity.sid,
63              },
64              workspaceSid: ctx.client._solution.sid,
65            };
66          });
67      });
68  }
69
70  function createTaskQueues() {
71    var ctx = this;
72    return this.client.activities.list()
73      .then(function(activities) {
74        var busyActivity = find(activities, {friendlyName: 'Busy'});
75        var reservedActivity = find(activities, {friendlyName: 'Reserved'});
76
77        return Promise.all([
78          ctx.client.taskQueues.create({
79            friendlyName: 'SMS',
80            targetWorkers: 'products HAS "ProgrammableSMS"',
81            assignmentActivitySid: busyActivity.sid,
82            reservationActivitySid: reservedActivity.sid,
83          }),
84          ctx.client.taskQueues.create({
85            friendlyName: 'Voice',
86            targetWorkers: 'products HAS "ProgrammableVoice"',
87            assignmentActivitySid: busyActivity.sid,
88            reservationActivitySid: reservedActivity.sid,
89          }),
90          ctx.client.taskQueues.create({
91            friendlyName: 'Default',
92            targetWorkers: '1==1',
93            assignmentActivitySid: busyActivity.sid,
94            reservationActivitySid: reservedActivity.sid,
95          }),
96        ])
97        .then(function(queues) {
98          ctx.queues = queues;
99        });
100      });
101  }
102
103  function createWorkers() {
104    var ctx = this;
105
106    return Promise.all([
107      ctx.createWorker({
108        name: 'Bob',
109        phoneNumber: process.env.BOB_NUMBER,
110        products: ['ProgrammableSMS'],
111      }),
112      ctx.createWorker({
113        name: 'Alice',
114        phoneNumber: process.env.ALICE_NUMBER,
115        products: ['ProgrammableVoice'],
116      })
117    ])
118    .then(function(workers) {
119      var bobWorker = workers[0];
120      var aliceWorker = workers[1];
121      var workerInfo = {};
122
123      workerInfo[process.env.ALICE_NUMBER] = aliceWorker.sid;
124      workerInfo[process.env.BOB_NUMBER] = bobWorker.sid;
125
126      return workerInfo;
127    });
128  }
129
130  function createWorkflowActivities() {
131    var ctx = this;
132    var activityNames = ['Idle', 'Busy', 'Offline', 'Reserved'];
133
134    return ctx.client.activities.list()
135      .then(function(activities) {
136        var existingActivities = map(activities, 'friendlyName');
137
138        var missingActivities = difference(activityNames, existingActivities);
139
140        var newActivities = map(missingActivities, function(friendlyName) {
141          return ctx.client.activities
142            .create({
143              friendlyName: friendlyName,
144              available: 'true'
145            });
146        });
147
148        return Promise.all(newActivities);
149      })
150      .then(function() {
151        return ctx.client.activities.list();
152      });
153  }
154
155  function createWorkflowConfig() {
156    var queues = this.queues;
157
158    if (!queues) {
159      throw new Error('Queues must be initialized.');
160    }
161
162    var defaultTarget = {
163      queue: find(queues, {friendlyName: 'Default'}).sid,
164      timeout: 30,
165      priority: 1,
166    };
167
168    var smsTarget = {
169      queue: find(queues, {friendlyName: 'SMS'}).sid,
170      timeout: 30,
171      priority: 5,
172    };
173
174    var voiceTarget = {
175      queue: find(queues, {friendlyName: 'Voice'}).sid,
176      timeout: 30,
177      priority: 5,
178    };
179
180    var rules = [
181      {
182        expression: 'selected_product=="ProgrammableSMS"',
183        targets: [smsTarget, defaultTarget],
184        timeout: 30,
185      },
186      {
187        expression: 'selected_product=="ProgrammableVoice"',
188        targets: [voiceTarget, defaultTarget],
189        timeout: 30,
190      },
191    ];
192
193    var config = {
194      task_routing: {
195        filters: rules,
196        default_filter: defaultTarget,
197      },
198    };
199
200    return JSON.stringify(config);
201  }
202
203  function setup() {
204    var ctx = this;
205
206    ctx.initClient();
207
208    return this.initWorkspace()
209      .then(createWorkflowActivities.bind(ctx))
210      .then(createTaskQueues.bind(ctx))
211      .then(createWorkflow.bind(ctx))
212      .then(function(workspaceInfo) {
213        return ctx.createWorkers()
214        .then(function(workerInfo) {
215          return [workerInfo, workspaceInfo];
216        });
217      });
218  }
219
220  function findByFriendlyName(friendlyName) {
221    var client = this.client;
222
223    return client.list()
224      .then(function (data) {
225        return find(data, {friendlyName: friendlyName});
226      });
227  }
228
229  function deleteByFriendlyName(friendlyName) {
230    var ctx = this;
231
232    return this.findByFriendlyName(friendlyName)
233      .then(function(workspace) {
234        if (workspace.remove) {
235          return workspace.remove();
236        }
237      });
238  }
239
240  function createWorkspace() {
241    return this.client.create({
242      friendlyName: WORKSPACE_NAME,
243      EVENT_CALLBACKUrl: EVENT_CALLBACK,
244    });
245  }
246
247  function initWorkspace() {
248    var ctx = this;
249    var client = this.client;
250
251    return ctx.findByFriendlyName(WORKSPACE_NAME)
252      .then(function(workspace) {
253        var newWorkspace;
254
255        if (workspace) {
256         newWorkspace = ctx.deleteByFriendlyName(WORKSPACE_NAME)
257                   .then(createWorkspace.bind(ctx));
258        } else {
259         newWorkspace = ctx.createWorkspace();
260        }
261
262        return newWorkspace;
263      })
264      .then(function(workspace) {
265        ctx.initClient(workspace.sid);
266
267        return workspace;
268      });
269  }
270
271  return {
272    createTaskQueues: createTaskQueues,
273    createWorker: createWorker,
274    createWorkers: createWorkers,
275    createWorkflow: createWorkflow,
276    createWorkflowActivities: createWorkflowActivities,
277    createWorkflowConfig: createWorkflowConfig,
278    createWorkspace: createWorkspace,
279    deleteByFriendlyName: deleteByFriendlyName,
280    findByFriendlyName: findByFriendlyName,
281    initClient: initClient,
282    initWorkspace: initWorkspace,
283    setup: setup,
284  };
285};

After creating our workers, let's set up the Task Queues.

Create the Task Queues

Next, we set up the Task Queues. Each with a friendlyName and a targetWorkers, which is an expression to match Workers. Our Task Queues are:

SMS - Will target Workers specialized in Programmable SMS, such as Bob, using the expression products HAS "ProgrammableSMS".
Voice - Will do the same for Programmable Voice Workers, such as Alice, using the expression products HAS "ProgrammableVoice".
Default - This queue targets all users and can be used when there are no specialist around for the chosen product. We can use the "1==1" expression here.

Create Task Queues

lib/workspace.js

1'use strict';
2
3var twilio = require('twilio');
4var find = require('lodash/find');
5var map = require('lodash/map');
6var difference = require('lodash/difference');
7var WORKSPACE_NAME = 'TaskRouter Node Workspace';
8var HOST = process.env.HOST;
9var EVENT_CALLBACK = `${HOST}/events`;
10var ACCOUNT_SID = process.env.TWILIO_ACCOUNT_SID;
11var API_KEY = process.env.TWILIO_API_KEY;
12var API_SECRET = process.env.TWILIO_API_SECRET;
13
14module.exports = function() {
15  function initClient(existingWorkspaceSid) {
16    if (!existingWorkspaceSid) {
17      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID }).taskrouter.v1.workspaces;
18    } else {
19      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID })
20      .taskrouter.v1.workspaces(existingWorkspaceSid);
21    }
22  }
23
24  function createWorker(opts) {
25    var ctx = this;
26
27    return this.client.activities.list({friendlyName: 'Idle'})
28    .then(function(idleActivity) {
29      return ctx.client.workers.create({
30        friendlyName: opts.name,
31        attributes: JSON.stringify({
32          'products': opts.products,
33          'contact_uri': opts.phoneNumber,
34        }),
35        activitySid: idleActivity.sid,
36      });
37    });
38  }
39
40  function createWorkflow() {
41    var ctx = this;
42    var config = this.createWorkflowConfig();
43
44    return ctx.client.workflows
45      .create({
46        friendlyName: 'Sales',
47        assignmentCallbackUrl: HOST + '/call/assignment',
48        fallbackAssignmentCallbackUrl: HOST + '/call/assignment',
49        taskReservationTimeout: 15,
50        configuration: config,
51      })
52      .then(function(workflow) {
53        return ctx.client.activities.list()
54          .then(function(activities) {
55            var idleActivity = find(activities, {friendlyName: 'Idle'});
56            var offlineActivity = find(activities, {friendlyName: 'Offline'});
57
58            return {
59              workflowSid: workflow.sid,
60              activities: {
61                idle: idleActivity.sid,
62                offline: offlineActivity.sid,
63              },
64              workspaceSid: ctx.client._solution.sid,
65            };
66          });
67      });
68  }
69
70  function createTaskQueues() {
71    var ctx = this;
72    return this.client.activities.list()
73      .then(function(activities) {
74        var busyActivity = find(activities, {friendlyName: 'Busy'});
75        var reservedActivity = find(activities, {friendlyName: 'Reserved'});
76
77        return Promise.all([
78          ctx.client.taskQueues.create({
79            friendlyName: 'SMS',
80            targetWorkers: 'products HAS "ProgrammableSMS"',
81            assignmentActivitySid: busyActivity.sid,
82            reservationActivitySid: reservedActivity.sid,
83          }),
84          ctx.client.taskQueues.create({
85            friendlyName: 'Voice',
86            targetWorkers: 'products HAS "ProgrammableVoice"',
87            assignmentActivitySid: busyActivity.sid,
88            reservationActivitySid: reservedActivity.sid,
89          }),
90          ctx.client.taskQueues.create({
91            friendlyName: 'Default',
92            targetWorkers: '1==1',
93            assignmentActivitySid: busyActivity.sid,
94            reservationActivitySid: reservedActivity.sid,
95          }),
96        ])
97        .then(function(queues) {
98          ctx.queues = queues;
99        });
100      });
101  }
102
103  function createWorkers() {
104    var ctx = this;
105
106    return Promise.all([
107      ctx.createWorker({
108        name: 'Bob',
109        phoneNumber: process.env.BOB_NUMBER,
110        products: ['ProgrammableSMS'],
111      }),
112      ctx.createWorker({
113        name: 'Alice',
114        phoneNumber: process.env.ALICE_NUMBER,
115        products: ['ProgrammableVoice'],
116      })
117    ])
118    .then(function(workers) {
119      var bobWorker = workers[0];
120      var aliceWorker = workers[1];
121      var workerInfo = {};
122
123      workerInfo[process.env.ALICE_NUMBER] = aliceWorker.sid;
124      workerInfo[process.env.BOB_NUMBER] = bobWorker.sid;
125
126      return workerInfo;
127    });
128  }
129
130  function createWorkflowActivities() {
131    var ctx = this;
132    var activityNames = ['Idle', 'Busy', 'Offline', 'Reserved'];
133
134    return ctx.client.activities.list()
135      .then(function(activities) {
136        var existingActivities = map(activities, 'friendlyName');
137
138        var missingActivities = difference(activityNames, existingActivities);
139
140        var newActivities = map(missingActivities, function(friendlyName) {
141          return ctx.client.activities
142            .create({
143              friendlyName: friendlyName,
144              available: 'true'
145            });
146        });
147
148        return Promise.all(newActivities);
149      })
150      .then(function() {
151        return ctx.client.activities.list();
152      });
153  }
154
155  function createWorkflowConfig() {
156    var queues = this.queues;
157
158    if (!queues) {
159      throw new Error('Queues must be initialized.');
160    }
161
162    var defaultTarget = {
163      queue: find(queues, {friendlyName: 'Default'}).sid,
164      timeout: 30,
165      priority: 1,
166    };
167
168    var smsTarget = {
169      queue: find(queues, {friendlyName: 'SMS'}).sid,
170      timeout: 30,
171      priority: 5,
172    };
173
174    var voiceTarget = {
175      queue: find(queues, {friendlyName: 'Voice'}).sid,
176      timeout: 30,
177      priority: 5,
178    };
179
180    var rules = [
181      {
182        expression: 'selected_product=="ProgrammableSMS"',
183        targets: [smsTarget, defaultTarget],
184        timeout: 30,
185      },
186      {
187        expression: 'selected_product=="ProgrammableVoice"',
188        targets: [voiceTarget, defaultTarget],
189        timeout: 30,
190      },
191    ];
192
193    var config = {
194      task_routing: {
195        filters: rules,
196        default_filter: defaultTarget,
197      },
198    };
199
200    return JSON.stringify(config);
201  }
202
203  function setup() {
204    var ctx = this;
205
206    ctx.initClient();
207
208    return this.initWorkspace()
209      .then(createWorkflowActivities.bind(ctx))
210      .then(createTaskQueues.bind(ctx))
211      .then(createWorkflow.bind(ctx))
212      .then(function(workspaceInfo) {
213        return ctx.createWorkers()
214        .then(function(workerInfo) {
215          return [workerInfo, workspaceInfo];
216        });
217      });
218  }
219
220  function findByFriendlyName(friendlyName) {
221    var client = this.client;
222
223    return client.list()
224      .then(function (data) {
225        return find(data, {friendlyName: friendlyName});
226      });
227  }
228
229  function deleteByFriendlyName(friendlyName) {
230    var ctx = this;
231
232    return this.findByFriendlyName(friendlyName)
233      .then(function(workspace) {
234        if (workspace.remove) {
235          return workspace.remove();
236        }
237      });
238  }
239
240  function createWorkspace() {
241    return this.client.create({
242      friendlyName: WORKSPACE_NAME,
243      EVENT_CALLBACKUrl: EVENT_CALLBACK,
244    });
245  }
246
247  function initWorkspace() {
248    var ctx = this;
249    var client = this.client;
250
251    return ctx.findByFriendlyName(WORKSPACE_NAME)
252      .then(function(workspace) {
253        var newWorkspace;
254
255        if (workspace) {
256         newWorkspace = ctx.deleteByFriendlyName(WORKSPACE_NAME)
257                   .then(createWorkspace.bind(ctx));
258        } else {
259         newWorkspace = ctx.createWorkspace();
260        }
261
262        return newWorkspace;
263      })
264      .then(function(workspace) {
265        ctx.initClient(workspace.sid);
266
267        return workspace;
268      });
269  }
270
271  return {
272    createTaskQueues: createTaskQueues,
273    createWorker: createWorker,
274    createWorkers: createWorkers,
275    createWorkflow: createWorkflow,
276    createWorkflowActivities: createWorkflowActivities,
277    createWorkflowConfig: createWorkflowConfig,
278    createWorkspace: createWorkspace,
279    deleteByFriendlyName: deleteByFriendlyName,
280    findByFriendlyName: findByFriendlyName,
281    initClient: initClient,
282    initWorkspace: initWorkspace,
283    setup: setup,
284  };
285};

We have a Workspace, Workers and Task Queues... what's left? A Workflow. Let's see how to create one next!

Create a Workflow

Finally, we create the Workflow using the following parameters:

friendlyName as the name of a Workflow.
assignmentCallbackUrl and fallbackAssignmentCallbackUrl as the public URL where a request will be made when this Workflow assigns a Task to a Worker. We will learn how to implement it on the next steps.
taskReservationTimeout as the maximum time we want to wait until a Worker is available for handling a Task.
configuration which is a set of rules for placing Tasks into Task Queues. The routing configuration will take a Task's attribute and match this with Task Queues. This application's Workflow rules are defined as:
- "selected_product==\ "ProgrammableSMS\"" expression for SMS Task Queue. This expression will match any Task with ProgrammableSMS as the selected_product attribute.
- "selected_product==\ "ProgrammableVoice\"" expression for Voice Task Queue.

Create a Workflow

lib/workspace.js

1'use strict';
2
3var twilio = require('twilio');
4var find = require('lodash/find');
5var map = require('lodash/map');
6var difference = require('lodash/difference');
7var WORKSPACE_NAME = 'TaskRouter Node Workspace';
8var HOST = process.env.HOST;
9var EVENT_CALLBACK = `${HOST}/events`;
10var ACCOUNT_SID = process.env.TWILIO_ACCOUNT_SID;
11var API_KEY = process.env.TWILIO_API_KEY;
12var API_SECRET = process.env.TWILIO_API_SECRET;
13
14module.exports = function() {
15  function initClient(existingWorkspaceSid) {
16    if (!existingWorkspaceSid) {
17      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID }).taskrouter.v1.workspaces;
18    } else {
19      this.client = twilio(API_KEY, API_SECRET, { accountSid: ACCOUNT_SID })
20      .taskrouter.v1.workspaces(existingWorkspaceSid);
21    }
22  }
23
24  function createWorker(opts) {
25    var ctx = this;
26
27    return this.client.activities.list({friendlyName: 'Idle'})
28    .then(function(idleActivity) {
29      return ctx.client.workers.create({
30        friendlyName: opts.name,
31        attributes: JSON.stringify({
32          'products': opts.products,
33          'contact_uri': opts.phoneNumber,
34        }),
35        activitySid: idleActivity.sid,
36      });
37    });
38  }
39
40  function createWorkflow() {
41    var ctx = this;
42    var config = this.createWorkflowConfig();
43
44    return ctx.client.workflows
45      .create({
46        friendlyName: 'Sales',
47        assignmentCallbackUrl: HOST + '/call/assignment',
48        fallbackAssignmentCallbackUrl: HOST + '/call/assignment',
49        taskReservationTimeout: 15,
50        configuration: config,
51      })
52      .then(function(workflow) {
53        return ctx.client.activities.list()
54          .then(function(activities) {
55            var idleActivity = find(activities, {friendlyName: 'Idle'});
56            var offlineActivity = find(activities, {friendlyName: 'Offline'});
57
58            return {
59              workflowSid: workflow.sid,
60              activities: {
61                idle: idleActivity.sid,
62                offline: offlineActivity.sid,
63              },
64              workspaceSid: ctx.client._solution.sid,
65            };
66          });
67      });
68  }
69
70  function createTaskQueues() {
71    var ctx = this;
72    return this.client.activities.list()
73      .then(function(activities) {
74        var busyActivity = find(activities, {friendlyName: 'Busy'});
75        var reservedActivity = find(activities, {friendlyName: 'Reserved'});
76
77        return Promise.all([
78          ctx.client.taskQueues.create({
79            friendlyName: 'SMS',
80            targetWorkers: 'products HAS "ProgrammableSMS"',
81            assignmentActivitySid: busyActivity.sid,
82            reservationActivitySid: reservedActivity.sid,
83          }),
84          ctx.client.taskQueues.create({
85            friendlyName: 'Voice',
86            targetWorkers: 'products HAS "ProgrammableVoice"',
87            assignmentActivitySid: busyActivity.sid,
88            reservationActivitySid: reservedActivity.sid,
89          }),
90          ctx.client.taskQueues.create({
91            friendlyName: 'Default',
92            targetWorkers: '1==1',
93            assignmentActivitySid: busyActivity.sid,
94            reservationActivitySid: reservedActivity.sid,
95          }),
96        ])
97        .then(function(queues) {
98          ctx.queues = queues;
99        });
100      });
101  }
102
103  function createWorkers() {
104    var ctx = this;
105
106    return Promise.all([
107      ctx.createWorker({
108        name: 'Bob',
109        phoneNumber: process.env.BOB_NUMBER,
110        products: ['ProgrammableSMS'],
111      }),
112      ctx.createWorker({
113        name: 'Alice',
114        phoneNumber: process.env.ALICE_NUMBER,
115        products: ['ProgrammableVoice'],
116      })
117    ])
118    .then(function(workers) {
119      var bobWorker = workers[0];
120      var aliceWorker = workers[1];
121      var workerInfo = {};
122
123      workerInfo[process.env.ALICE_NUMBER] = aliceWorker.sid;
124      workerInfo[process.env.BOB_NUMBER] = bobWorker.sid;
125
126      return workerInfo;
127    });
128  }
129
130  function createWorkflowActivities() {
131    var ctx = this;
132    var activityNames = ['Idle', 'Busy', 'Offline', 'Reserved'];
133
134    return ctx.client.activities.list()
135      .then(function(activities) {
136        var existingActivities = map(activities, 'friendlyName');
137
138        var missingActivities = difference(activityNames, existingActivities);
139
140        var newActivities = map(missingActivities, function(friendlyName) {
141          return ctx.client.activities
142            .create({
143              friendlyName: friendlyName,
144              available: 'true'
145            });
146        });
147
148        return Promise.all(newActivities);
149      })
150      .then(function() {
151        return ctx.client.activities.list();
152      });
153  }
154
155  function createWorkflowConfig() {
156    var queues = this.queues;
157
158    if (!queues) {
159      throw new Error('Queues must be initialized.');
160    }
161
162    var defaultTarget = {
163      queue: find(queues, {friendlyName: 'Default'}).sid,
164      timeout: 30,
165      priority: 1,
166    };
167
168    var smsTarget = {
169      queue: find(queues, {friendlyName: 'SMS'}).sid,
170      timeout: 30,
171      priority: 5,
172    };
173
174    var voiceTarget = {
175      queue: find(queues, {friendlyName: 'Voice'}).sid,
176      timeout: 30,
177      priority: 5,
178    };
179
180    var rules = [
181      {
182        expression: 'selected_product=="ProgrammableSMS"',
183        targets: [smsTarget, defaultTarget],
184        timeout: 30,
185      },
186      {
187        expression: 'selected_product=="ProgrammableVoice"',
188        targets: [voiceTarget, defaultTarget],
189        timeout: 30,
190      },
191    ];
192
193    var config = {
194      task_routing: {
195        filters: rules,
196        default_filter: defaultTarget,
197      },
198    };
199
200    return JSON.stringify(config);
201  }
202
203  function setup() {
204    var ctx = this;
205
206    ctx.initClient();
207
208    return this.initWorkspace()
209      .then(createWorkflowActivities.bind(ctx))
210      .then(createTaskQueues.bind(ctx))
211      .then(createWorkflow.bind(ctx))
212      .then(function(workspaceInfo) {
213        return ctx.createWorkers()
214        .then(function(workerInfo) {
215          return [workerInfo, workspaceInfo];
216        });
217      });
218  }
219
220  function findByFriendlyName(friendlyName) {
221    var client = this.client;
222
223    return client.list()
224      .then(function (data) {
225        return find(data, {friendlyName: friendlyName});
226      });
227  }
228
229  function deleteByFriendlyName(friendlyName) {
230    var ctx = this;
231
232    return this.findByFriendlyName(friendlyName)
233      .then(function(workspace) {
234        if (workspace.remove) {
235          return workspace.remove();
236        }
237      });
238  }
239
240  function createWorkspace() {
241    return this.client.create({
242      friendlyName: WORKSPACE_NAME,
243      EVENT_CALLBACKUrl: EVENT_CALLBACK,
244    });
245  }
246
247  function initWorkspace() {
248    var ctx = this;
249    var client = this.client;
250
251    return ctx.findByFriendlyName(WORKSPACE_NAME)
252      .then(function(workspace) {
253        var newWorkspace;
254
255        if (workspace) {
256         newWorkspace = ctx.deleteByFriendlyName(WORKSPACE_NAME)
257                   .then(createWorkspace.bind(ctx));
258        } else {
259         newWorkspace = ctx.createWorkspace();
260        }
261
262        return newWorkspace;
263      })
264      .then(function(workspace) {
265        ctx.initClient(workspace.sid);
266
267        return workspace;
268      });
269  }
270
271  return {
272    createTaskQueues: createTaskQueues,
273    createWorker: createWorker,
274    createWorkers: createWorkers,
275    createWorkflow: createWorkflow,
276    createWorkflowActivities: createWorkflowActivities,
277    createWorkflowConfig: createWorkflowConfig,
278    createWorkspace: createWorkspace,
279    deleteByFriendlyName: deleteByFriendlyName,
280    findByFriendlyName: findByFriendlyName,
281    initClient: initClient,
282    initWorkspace: initWorkspace,
283    setup: setup,
284  };
285};

Our workspace is completely setup. Now it's time to see how we use it to route calls.

Handle Twilio's Request

Right after receiving a call, Twilio will send a request to the URL specified on the number's configuration.

The endpoint will then process the request and generate a TwiML response. We'll use the Say verb to give the user product alternatives they can select by pressing a key. The Gather verb allows us to capture the user's key press.

Handling Twilio's Requests

routes/call.js

1'use strict';
2
3var express = require('express'),
4    router = express.Router(),
5    VoiceResponse = require('twilio/lib/twiml/VoiceResponse');
6
7module.exports = function (app) {
8  // POST /call/incoming
9  router.post('/incoming/', function (req, res) {
10    var twimlResponse = new VoiceResponse();
11    var gather = twimlResponse.gather({
12      numDigits: 1,
13      action: '/call/enqueue',
14      method: 'POST'
15    });
16    gather.say('For Programmable SMS, press one. For Voice, press any other key.');
17    res.type('text/xml');
18    res.send(twimlResponse.toString());
19  });
20
21  // POST /call/enqueue
22  router.post('/enqueue/', function (req, res) {
23    var pressedKey = req.body.Digits;
24    var twimlResponse = new VoiceResponse();
25    var selectedProduct = (pressedKey === '1') ? 'ProgrammableSMS' : 'ProgrammableVoice';
26    var enqueue = twimlResponse.enqueueTask(
27      {workflowSid: app.get('workspaceInfo').workflowSid}
28    );
29    enqueue.task({}, JSON.stringify({selected_product: selectedProduct}));
30
31    res.type('text/xml');
32    res.send(twimlResponse.toString());
33  });
34
35  // POST /call/assignment
36  router.post('/assignment/', function (req, res) {
37    res.type('application/json');
38    res.send({
39      instruction: "dequeue",
40      post_work_activity_sid: app.get('workspaceInfo').activities.idle
41    });
42  });
43
44  return router;
45};

We just asked the caller to choose a product, next we will use their choice to create the appropriate Task.

Create a Task

This is the endpoint set as the action URL on the Gather verb on the previous step. A request is made to this endpoint when the user presses a key during the call. This request has a Digits parameter that holds the pressed keys. A Task will be created based on the pressed digit with the selected_product as an attribute. The Workflow will take this Task's attributes and match with the configured expressions in order to find a Task Queue for this Task, so an appropriate available Worker can be assigned to handle it.

We use the Enqueue verb with a WorkflowSid attribute to integrate with TaskRouter. Then the voice call will be put on hold while TaskRouter tries to find an available Worker to handle this Task.

Create a Task

routes/call.js

1'use strict';
2
3var express = require('express'),
4    router = express.Router(),
5    VoiceResponse = require('twilio/lib/twiml/VoiceResponse');
6
7module.exports = function (app) {
8  // POST /call/incoming
9  router.post('/incoming/', function (req, res) {
10    var twimlResponse = new VoiceResponse();
11    var gather = twimlResponse.gather({
12      numDigits: 1,
13      action: '/call/enqueue',
14      method: 'POST'
15    });
16    gather.say('For Programmable SMS, press one. For Voice, press any other key.');
17    res.type('text/xml');
18    res.send(twimlResponse.toString());
19  });
20
21  // POST /call/enqueue
22  router.post('/enqueue/', function (req, res) {
23    var pressedKey = req.body.Digits;
24    var twimlResponse = new VoiceResponse();
25    var selectedProduct = (pressedKey === '1') ? 'ProgrammableSMS' : 'ProgrammableVoice';
26    var enqueue = twimlResponse.enqueueTask(
27      {workflowSid: app.get('workspaceInfo').workflowSid}
28    );
29    enqueue.task({}, JSON.stringify({selected_product: selectedProduct}));
30
31    res.type('text/xml');
32    res.send(twimlResponse.toString());
33  });
34
35  // POST /call/assignment
36  router.post('/assignment/', function (req, res) {
37    res.type('application/json');
38    res.send({
39      instruction: "dequeue",
40      post_work_activity_sid: app.get('workspaceInfo').activities.idle
41    });
42  });
43
44  return router;
45};

After sending a Task to Twilio, let's see how we tell TaskRouter which Worker to use to execute that task.

Assign a Worker

When TaskRouter selects a Worker, it does the following:

The Task's Assignment Status is set to 'reserved'.
A Reservation instance is generated, linking the Task to the selected Worker.
At the same time the Reservation is created, a POST request is made to the Workflow's AssignmentCallbackURL, which was configured while creating the Workflow. This request includes the full details of the Task, the selected Worker, and the Reservation.

Handling this Assignment Callback is a key component of building a TaskRouter application as we can instruct how the Worker will handle a Task. We could send a text, email, push notifications or make a call.

Since we created this Task during a voice call with an Enqueue verb, lets instruct TaskRouter to dequeue the call and dial a Worker. If we do not specify a to parameter with a phone number, TaskRouter will pick the Worker's contact_uri attribute.

We also send a post_work_activity_sid which will tell TaskRouter which Activity to assign this worker after the call ends.

Assign a Worker

routes/call.js

1'use strict';
2
3var express = require('express'),
4    router = express.Router(),
5    VoiceResponse = require('twilio/lib/twiml/VoiceResponse');
6
7module.exports = function (app) {
8  // POST /call/incoming
9  router.post('/incoming/', function (req, res) {
10    var twimlResponse = new VoiceResponse();
11    var gather = twimlResponse.gather({
12      numDigits: 1,
13      action: '/call/enqueue',
14      method: 'POST'
15    });
16    gather.say('For Programmable SMS, press one. For Voice, press any other key.');
17    res.type('text/xml');
18    res.send(twimlResponse.toString());
19  });
20
21  // POST /call/enqueue
22  router.post('/enqueue/', function (req, res) {
23    var pressedKey = req.body.Digits;
24    var twimlResponse = new VoiceResponse();
25    var selectedProduct = (pressedKey === '1') ? 'ProgrammableSMS' : 'ProgrammableVoice';
26    var enqueue = twimlResponse.enqueueTask(
27      {workflowSid: app.get('workspaceInfo').workflowSid}
28    );
29    enqueue.task({}, JSON.stringify({selected_product: selectedProduct}));
30
31    res.type('text/xml');
32    res.send(twimlResponse.toString());
33  });
34
35  // POST /call/assignment
36  router.post('/assignment/', function (req, res) {
37    res.type('application/json');
38    res.send({
39      instruction: "dequeue",
40      post_work_activity_sid: app.get('workspaceInfo').activities.idle
41    });
42  });
43
44  return router;
45};

Now that our Tasks are routed properly, let's deal with missed calls in the next step.

Collect Missed Calls

This endpoint will be called after each TaskRouter Event is triggered. In our application, we are trying to collect missed calls, so we would like to handle the workflow.timeout event. This event is triggered when the Task waits more than the limit set on the Workflow Configuration-- or rather when no worker is available.

Here we use TwilioRestClient to route this call to a Voicemail Twimlet. Twimlets are tiny web applications for voice. This one will generate a TwiML response using Say verb and record a message using Record verb. The recorded message will then be transcribed and sent to the email address configured.

Note that we are also listening for task.canceled. This is triggered when the customer hangs up before being assigned to an agent, therefore canceling the task. Capturing this event allows us to collect the information from the customers that hang up before the Workflow times out.

Collect Missed Calls

routes/events.js

1'use strict';
2
3var express = require('express'),
4  MissedCall = require('../models/missed-call'),
5  util = require('util'),
6  querystring = require('querystring'),
7  router = express.Router(),
8  Q = require('q');
9
10// POST /events
11router.post('/', function (req, res) {
12  var eventType = req.body.EventType;
13  var taskAttributes = (req.body.TaskAttributes)? JSON.parse(req.body.TaskAttributes) : {};
14
15  function saveMissedCall(){
16    return MissedCall.create({
17      selectedProduct: taskAttributes.selected_product,
18      phoneNumber: taskAttributes.from
19    });
20  }
21
22  var eventHandler = {
23    'task.canceled': saveMissedCall,
24    'workflow.timeout': function() {
25      return saveMissedCall().then(voicemail(taskAttributes.call_sid));
26    },
27    'worker.activity.update': function(){
28      var workerAttributes = JSON.parse(req.body.WorkerAttributes);
29      if (req.body.WorkerActivityName === 'Offline') {
30        notifyOfflineStatus(workerAttributes.contact_uri);
31      }
32      return Q.resolve({});
33    },
34    'default': function() { return Q.resolve({}); }
35  };
36
37  (eventHandler[eventType] || eventHandler['default'])().then(function () {
38    res.json({});
39  });
40});
41
42function voicemail (callSid){
43  var client = buildClient(),
44      query = querystring.stringify({
45        Message: 'Sorry, All agents are busy. Please leave a message. We\'ll call you as soon as possible',
46        Email: process.env.MISSED_CALLS_EMAIL_ADDRESS}),
47      voicemailUrl = util.format("https://twimlets.com/voicemail?%s", query);
48
49  client.calls(callSid).update({
50    method: 'POST',
51    url: voicemailUrl
52  });
53}
54
55function notifyOfflineStatus(phone_number) {
56  var client = buildClient(),
57      message = 'Your status has changed to Offline. Reply with "On" to get back Online';
58  client.sendMessage({
59    to: phone_number,
60    from: process.env.TWILIO_NUMBER,
61    body: message
62  });
63}
64
65function buildClient() {
66  var accountSid = process.env.TWILIO_ACCOUNT_SID,
67      apiKey = process.env.TWILIO_API_KEY,
68      apiSecret = process.env.TWILIO_API_SECRET;
69  return require('twilio')(apiKey, apiSecret, { accountSid: accountSid });
70}
71
72module.exports = router;

Most of the features of our application are implemented. The last piece is allowing the Workers to change their availability status. Let's see how to do that next.

Change a Worker's Activity

We have created this endpoint, so a worker can send an SMS message to the support line with the command "On" or "Off" to change their availability status.

This is important as a worker's activity will change to Offline when they miss a call. When this happens, they receive an SMS letting them know that their activity has changed, and that they can reply with the On command to make themselves available for incoming calls again.

Handle Message to update the Worker Status

routes/sms.js

1'use strict';
2
3var express = require('express'),
4    router = express.Router(),
5    twimlGenerator = require('../lib/twiml-generator');
6
7module.exports = function (app) {
8  // POST /sms/incoming
9  router.post('/incoming/', function (req, res) {
10    var targetActivity = (req.body.Body.toLowerCase() === "on")? "idle":"offline";
11    var activitySid = app.get('workspaceInfo').activities[targetActivity];
12    changeWorkerActivitySid(req.body.From, activitySid);
13    res.type('text/xml');
14    res.send(twimlGenerator.generateConfirmMessage(targetActivity));
15  });
16
17  function changeWorkerActivitySid(workerNumber, activitySid){
18    var accountSid = process.env.TWILIO_ACCOUNT_SID,
19        apiKey = process.env.TWILIO_API_KEY,
20        apiSecret = process.env.TWILIO_API_SECRET,
21        workspaceSid = app.get('workspaceInfo').workspaceSid,
22        workerSid = app.get('workerInfo')[workerNumber],
23        client = require('twilio')(apiKey, apiSecret, { accountSid: accountSid });
24    client.taskrouter.v1
25      .workspaces(workspaceSid)
26      .workers(workerSid)
27      .update({activitySid: activitySid});
28  }
29  return router;
30};

You've finished this tutorial and built a dynamic call center that routes calls to specialist agents with TaskRouter.

Where to Next?

If you're a Node.js/Express developer working with Twilio, you might enjoy these other tutorials:

Warm-Transfer

Have you ever been disconnected from a support call while being transferred to another support agent? Warm transfer eliminates this problem. Using Twilio powered warm transfers your agents will have the ability to conference in another agent in realtime.

Automated-Survey

Instantly collect structured data from your users with a survey conducted over a call or SMS text messages.