Dynamic Call Center with Ruby and Rails

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.

This is what the application does at a high level

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 Ruby on Rails application, this step will be executed in the initialization phase every time you run 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

We'll use a TaskRouterClient provided in the twilio-ruby gem to create and configure the workspace.

Create, Setup and Configure the Workspace

lib/workspace_config.rb

1class WorkspaceConfig
2  WORKSPACE_NAME          = 'Rails Workspace'.freeze
3  WORKFLOW_NAME           = 'Sales'.freeze
4  WORKFLOW_TIMEOUT        = ENV['WORKFLOW_TIMEOUT'].freeze
5  QUEUE_TIMEOUT           = ENV['QUEUE_TIMEOUT'].freeze
6  ASSIGNMENT_CALLBACK_URL = ENV['ASSIGNMENT_CALLBACK_URL'].freeze
7  EVENT_CALLBACK_URL      = ENV['EVENT_CALLBACK_URL'].freeze
8  BOB_NUMBER              = ENV['BOB_NUMBER'].freeze
9  ALICE_NUMBER            = ENV['ALICE_NUMBER'].freeze
10
11  def self.setup
12    puts 'Configuring workspace, please wait ...'
13    new.setup
14    puts 'Workspace ready!'
15  end
16
17  def initialize
18    @account_sid = ENV['TWILIO_ACCOUNT_SID']
19    @auth_token  = ENV['TWILIO_AUTH_TOKEN']
20    @client      = taskrouter_client
21  end
22
23  def setup
24    @workspace_sid = create_workspace
25    @client = taskrouter_client
26    WorkspaceInfo.instance.workers = create_workers
27    workflow_sid = create_workflow.sid
28    WorkspaceInfo.instance.workflow_sid = workflow_sid
29    idle_activity_sid = activity_by_name('Idle').sid
30    WorkspaceInfo.instance.post_work_activity_sid = idle_activity_sid
31    WorkspaceInfo.instance.idle_activity_sid = idle_activity_sid
32    WorkspaceInfo.instance.offline_activity_sid = activity_by_name('Offline').sid
33    WorkspaceInfo.instance.workspace_sid = @workspace_sid
34  end
35
36  private
37
38  attr_reader :client, :account_sid, :auth_token
39
40  def taskrouter_client
41    client_instance = Twilio::REST::Client.new(
42      account_sid,
43      auth_token
44    )
45
46    client_instance.taskrouter.v1
47  end
48
49  def create_workspace
50    workspace = client.workspaces.list(friendly_name: WORKSPACE_NAME).first
51    workspace.delete unless workspace.nil?
52
53    workspace = client.workspaces.create(
54      friendly_name: WORKSPACE_NAME,
55      event_callback_url: EVENT_CALLBACK_URL
56    )
57
58    workspace.sid
59  end
60
61  def create_workers
62    bob_attributes = "{\"products\": [\"ProgrammableSMS\"], \"contact_uri\": \"#{BOB_NUMBER}\"}"
63    alice_attributes = "{\"products\": [\"ProgrammableVoice\"], \"contact_uri\": \"#{ALICE_NUMBER}\"}"
64
65    bob   = create_worker('Bob', bob_attributes)
66    alice = create_worker('Alice', alice_attributes)
67
68    {
69      BOB_NUMBER   => { sid: bob.sid,   name: 'Bob' },
70      ALICE_NUMBER => { sid: alice.sid, name: 'Alice' }
71    }
72  end
73
74  def create_worker(name, attributes)
75    client.workspaces(@workspace_sid).workers.create(
76      friendly_name: name,
77      attributes:    attributes,
78      activity_sid:  activity_by_name('Idle').sid
79    )
80  end
81
82  def activity_by_name(name)
83    client.workspaces(@workspace_sid).activities.list(friendly_name: name).first
84  end
85
86  def create_task_queues
87    reservation_activity_sid = activity_by_name('Reserved').sid
88    assignment_activity_sid  = activity_by_name('Busy').sid
89
90    voice_queue = create_task_queue('Voice', reservation_activity_sid,
91                                    assignment_activity_sid,
92                                    "products HAS 'ProgrammableVoice'")
93
94    sms_queue = create_task_queue('SMS', reservation_activity_sid,
95                                  assignment_activity_sid,
96                                  "products HAS 'ProgrammableSMS'")
97
98    all_queue = create_task_queue('All', reservation_activity_sid,
99                                  assignment_activity_sid, '1==1')
100
101    { voice: voice_queue, sms: sms_queue, all: all_queue }
102  end
103
104  def create_task_queue(name, reservation_sid, assignment_sid, target_workers)
105    client.workspaces(@workspace_sid).task_queues.create(
106      friendly_name: name,
107      reservation_activity_sid: reservation_sid,
108      assignment_activity_sid: assignment_sid,
109      target_workers: target_workers
110    )
111  end
112
113  def create_workflow
114    queues = create_task_queues
115    config = workflow_config(queues)
116
117    client.workspaces(@workspace_sid).workflows.create(
118      configuration: config.to_json,
119      friendly_name: WORKFLOW_NAME,
120      assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
121      fallback_assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
122      task_reservation_timeout: WORKFLOW_TIMEOUT
123    )
124  end
125
126  def workspace_sid
127    @workspace_sid || 'no_workspace_yet'
128  end
129
130  def workflow_config(queues)
131    default_target = default_rule_target(queues[:all].sid)
132
133    {
134      task_routing: {
135        filters: [
136          {
137            expression: 'selected_product=="ProgrammableVoice"',
138            targets: [
139              rule_target(queues[:voice].sid),
140              default_target
141            ]
142          },
143          {
144            expression: 'selected_product=="ProgrammableSMS"',
145            targets: [
146              rule_target(queues[:sms].sid),
147              default_target
148            ]
149          }
150        ],
151        default_filter: default_target
152      }
153    }
154  end
155
156  def rule_target(sid)
157    { queue: sid, priority: 5, timeout: QUEUE_TIMEOUT }
158  end
159
160  def default_rule_target(sid)
161    {
162      queue: sid,
163      priority: 1,
164      timeout: QUEUE_TIMEOUT,
165      expression: '1==1'
166    }
167  end
168end

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 friendly_name as the one we are trying to create. In order to create a workspace we need to provide a friendly_name and a callback_url where a requests will be made every time an event is triggered in our workspace.

See how to create a new workspace

lib/workspace_config.rb

1class WorkspaceConfig
2  WORKSPACE_NAME          = 'Rails Workspace'.freeze
3  WORKFLOW_NAME           = 'Sales'.freeze
4  WORKFLOW_TIMEOUT        = ENV['WORKFLOW_TIMEOUT'].freeze
5  QUEUE_TIMEOUT           = ENV['QUEUE_TIMEOUT'].freeze
6  ASSIGNMENT_CALLBACK_URL = ENV['ASSIGNMENT_CALLBACK_URL'].freeze
7  EVENT_CALLBACK_URL      = ENV['EVENT_CALLBACK_URL'].freeze
8  BOB_NUMBER              = ENV['BOB_NUMBER'].freeze
9  ALICE_NUMBER            = ENV['ALICE_NUMBER'].freeze
10
11  def self.setup
12    puts 'Configuring workspace, please wait ...'
13    new.setup
14    puts 'Workspace ready!'
15  end
16
17  def initialize
18    @account_sid = ENV['TWILIO_ACCOUNT_SID']
19    @auth_token  = ENV['TWILIO_AUTH_TOKEN']
20    @client      = taskrouter_client
21  end
22
23  def setup
24    @workspace_sid = create_workspace
25    @client = taskrouter_client
26    WorkspaceInfo.instance.workers = create_workers
27    workflow_sid = create_workflow.sid
28    WorkspaceInfo.instance.workflow_sid = workflow_sid
29    idle_activity_sid = activity_by_name('Idle').sid
30    WorkspaceInfo.instance.post_work_activity_sid = idle_activity_sid
31    WorkspaceInfo.instance.idle_activity_sid = idle_activity_sid
32    WorkspaceInfo.instance.offline_activity_sid = activity_by_name('Offline').sid
33    WorkspaceInfo.instance.workspace_sid = @workspace_sid
34  end
35
36  private
37
38  attr_reader :client, :account_sid, :auth_token
39
40  def taskrouter_client
41    client_instance = Twilio::REST::Client.new(
42      account_sid,
43      auth_token
44    )
45
46    client_instance.taskrouter.v1
47  end
48
49  def create_workspace
50    workspace = client.workspaces.list(friendly_name: WORKSPACE_NAME).first
51    workspace.delete unless workspace.nil?
52
53    workspace = client.workspaces.create(
54      friendly_name: WORKSPACE_NAME,
55      event_callback_url: EVENT_CALLBACK_URL
56    )
57
58    workspace.sid
59  end
60
61  def create_workers
62    bob_attributes = "{\"products\": [\"ProgrammableSMS\"], \"contact_uri\": \"#{BOB_NUMBER}\"}"
63    alice_attributes = "{\"products\": [\"ProgrammableVoice\"], \"contact_uri\": \"#{ALICE_NUMBER}\"}"
64
65    bob   = create_worker('Bob', bob_attributes)
66    alice = create_worker('Alice', alice_attributes)
67
68    {
69      BOB_NUMBER   => { sid: bob.sid,   name: 'Bob' },
70      ALICE_NUMBER => { sid: alice.sid, name: 'Alice' }
71    }
72  end
73
74  def create_worker(name, attributes)
75    client.workspaces(@workspace_sid).workers.create(
76      friendly_name: name,
77      attributes:    attributes,
78      activity_sid:  activity_by_name('Idle').sid
79    )
80  end
81
82  def activity_by_name(name)
83    client.workspaces(@workspace_sid).activities.list(friendly_name: name).first
84  end
85
86  def create_task_queues
87    reservation_activity_sid = activity_by_name('Reserved').sid
88    assignment_activity_sid  = activity_by_name('Busy').sid
89
90    voice_queue = create_task_queue('Voice', reservation_activity_sid,
91                                    assignment_activity_sid,
92                                    "products HAS 'ProgrammableVoice'")
93
94    sms_queue = create_task_queue('SMS', reservation_activity_sid,
95                                  assignment_activity_sid,
96                                  "products HAS 'ProgrammableSMS'")
97
98    all_queue = create_task_queue('All', reservation_activity_sid,
99                                  assignment_activity_sid, '1==1')
100
101    { voice: voice_queue, sms: sms_queue, all: all_queue }
102  end
103
104  def create_task_queue(name, reservation_sid, assignment_sid, target_workers)
105    client.workspaces(@workspace_sid).task_queues.create(
106      friendly_name: name,
107      reservation_activity_sid: reservation_sid,
108      assignment_activity_sid: assignment_sid,
109      target_workers: target_workers
110    )
111  end
112
113  def create_workflow
114    queues = create_task_queues
115    config = workflow_config(queues)
116
117    client.workspaces(@workspace_sid).workflows.create(
118      configuration: config.to_json,
119      friendly_name: WORKFLOW_NAME,
120      assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
121      fallback_assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
122      task_reservation_timeout: WORKFLOW_TIMEOUT
123    )
124  end
125
126  def workspace_sid
127    @workspace_sid || 'no_workspace_yet'
128  end
129
130  def workflow_config(queues)
131    default_target = default_rule_target(queues[:all].sid)
132
133    {
134      task_routing: {
135        filters: [
136          {
137            expression: 'selected_product=="ProgrammableVoice"',
138            targets: [
139              rule_target(queues[:voice].sid),
140              default_target
141            ]
142          },
143          {
144            expression: 'selected_product=="ProgrammableSMS"',
145            targets: [
146              rule_target(queues[:sms].sid),
147              default_target
148            ]
149          }
150        ],
151        default_filter: default_target
152      }
153    }
154  end
155
156  def rule_target(sid)
157    { queue: sid, priority: 5, timeout: QUEUE_TIMEOUT }
158  end
159
160  def default_rule_target(sid)
161    {
162      queue: sid,
163      priority: 1,
164      timeout: QUEUE_TIMEOUT,
165      expression: '1==1'
166    }
167  end
168end

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 activity_sid 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_config.rb

1class WorkspaceConfig
2  WORKSPACE_NAME          = 'Rails Workspace'.freeze
3  WORKFLOW_NAME           = 'Sales'.freeze
4  WORKFLOW_TIMEOUT        = ENV['WORKFLOW_TIMEOUT'].freeze
5  QUEUE_TIMEOUT           = ENV['QUEUE_TIMEOUT'].freeze
6  ASSIGNMENT_CALLBACK_URL = ENV['ASSIGNMENT_CALLBACK_URL'].freeze
7  EVENT_CALLBACK_URL      = ENV['EVENT_CALLBACK_URL'].freeze
8  BOB_NUMBER              = ENV['BOB_NUMBER'].freeze
9  ALICE_NUMBER            = ENV['ALICE_NUMBER'].freeze
10
11  def self.setup
12    puts 'Configuring workspace, please wait ...'
13    new.setup
14    puts 'Workspace ready!'
15  end
16
17  def initialize
18    @account_sid = ENV['TWILIO_ACCOUNT_SID']
19    @auth_token  = ENV['TWILIO_AUTH_TOKEN']
20    @client      = taskrouter_client
21  end
22
23  def setup
24    @workspace_sid = create_workspace
25    @client = taskrouter_client
26    WorkspaceInfo.instance.workers = create_workers
27    workflow_sid = create_workflow.sid
28    WorkspaceInfo.instance.workflow_sid = workflow_sid
29    idle_activity_sid = activity_by_name('Idle').sid
30    WorkspaceInfo.instance.post_work_activity_sid = idle_activity_sid
31    WorkspaceInfo.instance.idle_activity_sid = idle_activity_sid
32    WorkspaceInfo.instance.offline_activity_sid = activity_by_name('Offline').sid
33    WorkspaceInfo.instance.workspace_sid = @workspace_sid
34  end
35
36  private
37
38  attr_reader :client, :account_sid, :auth_token
39
40  def taskrouter_client
41    client_instance = Twilio::REST::Client.new(
42      account_sid,
43      auth_token
44    )
45
46    client_instance.taskrouter.v1
47  end
48
49  def create_workspace
50    workspace = client.workspaces.list(friendly_name: WORKSPACE_NAME).first
51    workspace.delete unless workspace.nil?
52
53    workspace = client.workspaces.create(
54      friendly_name: WORKSPACE_NAME,
55      event_callback_url: EVENT_CALLBACK_URL
56    )
57
58    workspace.sid
59  end
60
61  def create_workers
62    bob_attributes = "{\"products\": [\"ProgrammableSMS\"], \"contact_uri\": \"#{BOB_NUMBER}\"}"
63    alice_attributes = "{\"products\": [\"ProgrammableVoice\"], \"contact_uri\": \"#{ALICE_NUMBER}\"}"
64
65    bob   = create_worker('Bob', bob_attributes)
66    alice = create_worker('Alice', alice_attributes)
67
68    {
69      BOB_NUMBER   => { sid: bob.sid,   name: 'Bob' },
70      ALICE_NUMBER => { sid: alice.sid, name: 'Alice' }
71    }
72  end
73
74  def create_worker(name, attributes)
75    client.workspaces(@workspace_sid).workers.create(
76      friendly_name: name,
77      attributes:    attributes,
78      activity_sid:  activity_by_name('Idle').sid
79    )
80  end
81
82  def activity_by_name(name)
83    client.workspaces(@workspace_sid).activities.list(friendly_name: name).first
84  end
85
86  def create_task_queues
87    reservation_activity_sid = activity_by_name('Reserved').sid
88    assignment_activity_sid  = activity_by_name('Busy').sid
89
90    voice_queue = create_task_queue('Voice', reservation_activity_sid,
91                                    assignment_activity_sid,
92                                    "products HAS 'ProgrammableVoice'")
93
94    sms_queue = create_task_queue('SMS', reservation_activity_sid,
95                                  assignment_activity_sid,
96                                  "products HAS 'ProgrammableSMS'")
97
98    all_queue = create_task_queue('All', reservation_activity_sid,
99                                  assignment_activity_sid, '1==1')
100
101    { voice: voice_queue, sms: sms_queue, all: all_queue }
102  end
103
104  def create_task_queue(name, reservation_sid, assignment_sid, target_workers)
105    client.workspaces(@workspace_sid).task_queues.create(
106      friendly_name: name,
107      reservation_activity_sid: reservation_sid,
108      assignment_activity_sid: assignment_sid,
109      target_workers: target_workers
110    )
111  end
112
113  def create_workflow
114    queues = create_task_queues
115    config = workflow_config(queues)
116
117    client.workspaces(@workspace_sid).workflows.create(
118      configuration: config.to_json,
119      friendly_name: WORKFLOW_NAME,
120      assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
121      fallback_assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
122      task_reservation_timeout: WORKFLOW_TIMEOUT
123    )
124  end
125
126  def workspace_sid
127    @workspace_sid || 'no_workspace_yet'
128  end
129
130  def workflow_config(queues)
131    default_target = default_rule_target(queues[:all].sid)
132
133    {
134      task_routing: {
135        filters: [
136          {
137            expression: 'selected_product=="ProgrammableVoice"',
138            targets: [
139              rule_target(queues[:voice].sid),
140              default_target
141            ]
142          },
143          {
144            expression: 'selected_product=="ProgrammableSMS"',
145            targets: [
146              rule_target(queues[:sms].sid),
147              default_target
148            ]
149          }
150        ],
151        default_filter: default_target
152      }
153    }
154  end
155
156  def rule_target(sid)
157    { queue: sid, priority: 5, timeout: QUEUE_TIMEOUT }
158  end
159
160  def default_rule_target(sid)
161    {
162      queue: sid,
163      priority: 1,
164      timeout: QUEUE_TIMEOUT,
165      expression: '1==1'
166    }
167  end
168end

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 friendly_name 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\"".
All - 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_config.rb

1class WorkspaceConfig
2  WORKSPACE_NAME          = 'Rails Workspace'.freeze
3  WORKFLOW_NAME           = 'Sales'.freeze
4  WORKFLOW_TIMEOUT        = ENV['WORKFLOW_TIMEOUT'].freeze
5  QUEUE_TIMEOUT           = ENV['QUEUE_TIMEOUT'].freeze
6  ASSIGNMENT_CALLBACK_URL = ENV['ASSIGNMENT_CALLBACK_URL'].freeze
7  EVENT_CALLBACK_URL      = ENV['EVENT_CALLBACK_URL'].freeze
8  BOB_NUMBER              = ENV['BOB_NUMBER'].freeze
9  ALICE_NUMBER            = ENV['ALICE_NUMBER'].freeze
10
11  def self.setup
12    puts 'Configuring workspace, please wait ...'
13    new.setup
14    puts 'Workspace ready!'
15  end
16
17  def initialize
18    @account_sid = ENV['TWILIO_ACCOUNT_SID']
19    @auth_token  = ENV['TWILIO_AUTH_TOKEN']
20    @client      = taskrouter_client
21  end
22
23  def setup
24    @workspace_sid = create_workspace
25    @client = taskrouter_client
26    WorkspaceInfo.instance.workers = create_workers
27    workflow_sid = create_workflow.sid
28    WorkspaceInfo.instance.workflow_sid = workflow_sid
29    idle_activity_sid = activity_by_name('Idle').sid
30    WorkspaceInfo.instance.post_work_activity_sid = idle_activity_sid
31    WorkspaceInfo.instance.idle_activity_sid = idle_activity_sid
32    WorkspaceInfo.instance.offline_activity_sid = activity_by_name('Offline').sid
33    WorkspaceInfo.instance.workspace_sid = @workspace_sid
34  end
35
36  private
37
38  attr_reader :client, :account_sid, :auth_token
39
40  def taskrouter_client
41    client_instance = Twilio::REST::Client.new(
42      account_sid,
43      auth_token
44    )
45
46    client_instance.taskrouter.v1
47  end
48
49  def create_workspace
50    workspace = client.workspaces.list(friendly_name: WORKSPACE_NAME).first
51    workspace.delete unless workspace.nil?
52
53    workspace = client.workspaces.create(
54      friendly_name: WORKSPACE_NAME,
55      event_callback_url: EVENT_CALLBACK_URL
56    )
57
58    workspace.sid
59  end
60
61  def create_workers
62    bob_attributes = "{\"products\": [\"ProgrammableSMS\"], \"contact_uri\": \"#{BOB_NUMBER}\"}"
63    alice_attributes = "{\"products\": [\"ProgrammableVoice\"], \"contact_uri\": \"#{ALICE_NUMBER}\"}"
64
65    bob   = create_worker('Bob', bob_attributes)
66    alice = create_worker('Alice', alice_attributes)
67
68    {
69      BOB_NUMBER   => { sid: bob.sid,   name: 'Bob' },
70      ALICE_NUMBER => { sid: alice.sid, name: 'Alice' }
71    }
72  end
73
74  def create_worker(name, attributes)
75    client.workspaces(@workspace_sid).workers.create(
76      friendly_name: name,
77      attributes:    attributes,
78      activity_sid:  activity_by_name('Idle').sid
79    )
80  end
81
82  def activity_by_name(name)
83    client.workspaces(@workspace_sid).activities.list(friendly_name: name).first
84  end
85
86  def create_task_queues
87    reservation_activity_sid = activity_by_name('Reserved').sid
88    assignment_activity_sid  = activity_by_name('Busy').sid
89
90    voice_queue = create_task_queue('Voice', reservation_activity_sid,
91                                    assignment_activity_sid,
92                                    "products HAS 'ProgrammableVoice'")
93
94    sms_queue = create_task_queue('SMS', reservation_activity_sid,
95                                  assignment_activity_sid,
96                                  "products HAS 'ProgrammableSMS'")
97
98    all_queue = create_task_queue('All', reservation_activity_sid,
99                                  assignment_activity_sid, '1==1')
100
101    { voice: voice_queue, sms: sms_queue, all: all_queue }
102  end
103
104  def create_task_queue(name, reservation_sid, assignment_sid, target_workers)
105    client.workspaces(@workspace_sid).task_queues.create(
106      friendly_name: name,
107      reservation_activity_sid: reservation_sid,
108      assignment_activity_sid: assignment_sid,
109      target_workers: target_workers
110    )
111  end
112
113  def create_workflow
114    queues = create_task_queues
115    config = workflow_config(queues)
116
117    client.workspaces(@workspace_sid).workflows.create(
118      configuration: config.to_json,
119      friendly_name: WORKFLOW_NAME,
120      assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
121      fallback_assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
122      task_reservation_timeout: WORKFLOW_TIMEOUT
123    )
124  end
125
126  def workspace_sid
127    @workspace_sid || 'no_workspace_yet'
128  end
129
130  def workflow_config(queues)
131    default_target = default_rule_target(queues[:all].sid)
132
133    {
134      task_routing: {
135        filters: [
136          {
137            expression: 'selected_product=="ProgrammableVoice"',
138            targets: [
139              rule_target(queues[:voice].sid),
140              default_target
141            ]
142          },
143          {
144            expression: 'selected_product=="ProgrammableSMS"',
145            targets: [
146              rule_target(queues[:sms].sid),
147              default_target
148            ]
149          }
150        ],
151        default_filter: default_target
152      }
153    }
154  end
155
156  def rule_target(sid)
157    { queue: sid, priority: 5, timeout: QUEUE_TIMEOUT }
158  end
159
160  def default_rule_target(sid)
161    {
162      queue: sid,
163      priority: 1,
164      timeout: QUEUE_TIMEOUT,
165      expression: '1==1'
166    }
167  end
168end

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:

friendly_name as the name of a Workflow.
assignment_callback_url and fallback_assignment_callback_url 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.
task_reservation_timeout 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_config.rb

1class WorkspaceConfig
2  WORKSPACE_NAME          = 'Rails Workspace'.freeze
3  WORKFLOW_NAME           = 'Sales'.freeze
4  WORKFLOW_TIMEOUT        = ENV['WORKFLOW_TIMEOUT'].freeze
5  QUEUE_TIMEOUT           = ENV['QUEUE_TIMEOUT'].freeze
6  ASSIGNMENT_CALLBACK_URL = ENV['ASSIGNMENT_CALLBACK_URL'].freeze
7  EVENT_CALLBACK_URL      = ENV['EVENT_CALLBACK_URL'].freeze
8  BOB_NUMBER              = ENV['BOB_NUMBER'].freeze
9  ALICE_NUMBER            = ENV['ALICE_NUMBER'].freeze
10
11  def self.setup
12    puts 'Configuring workspace, please wait ...'
13    new.setup
14    puts 'Workspace ready!'
15  end
16
17  def initialize
18    @account_sid = ENV['TWILIO_ACCOUNT_SID']
19    @auth_token  = ENV['TWILIO_AUTH_TOKEN']
20    @client      = taskrouter_client
21  end
22
23  def setup
24    @workspace_sid = create_workspace
25    @client = taskrouter_client
26    WorkspaceInfo.instance.workers = create_workers
27    workflow_sid = create_workflow.sid
28    WorkspaceInfo.instance.workflow_sid = workflow_sid
29    idle_activity_sid = activity_by_name('Idle').sid
30    WorkspaceInfo.instance.post_work_activity_sid = idle_activity_sid
31    WorkspaceInfo.instance.idle_activity_sid = idle_activity_sid
32    WorkspaceInfo.instance.offline_activity_sid = activity_by_name('Offline').sid
33    WorkspaceInfo.instance.workspace_sid = @workspace_sid
34  end
35
36  private
37
38  attr_reader :client, :account_sid, :auth_token
39
40  def taskrouter_client
41    client_instance = Twilio::REST::Client.new(
42      account_sid,
43      auth_token
44    )
45
46    client_instance.taskrouter.v1
47  end
48
49  def create_workspace
50    workspace = client.workspaces.list(friendly_name: WORKSPACE_NAME).first
51    workspace.delete unless workspace.nil?
52
53    workspace = client.workspaces.create(
54      friendly_name: WORKSPACE_NAME,
55      event_callback_url: EVENT_CALLBACK_URL
56    )
57
58    workspace.sid
59  end
60
61  def create_workers
62    bob_attributes = "{\"products\": [\"ProgrammableSMS\"], \"contact_uri\": \"#{BOB_NUMBER}\"}"
63    alice_attributes = "{\"products\": [\"ProgrammableVoice\"], \"contact_uri\": \"#{ALICE_NUMBER}\"}"
64
65    bob   = create_worker('Bob', bob_attributes)
66    alice = create_worker('Alice', alice_attributes)
67
68    {
69      BOB_NUMBER   => { sid: bob.sid,   name: 'Bob' },
70      ALICE_NUMBER => { sid: alice.sid, name: 'Alice' }
71    }
72  end
73
74  def create_worker(name, attributes)
75    client.workspaces(@workspace_sid).workers.create(
76      friendly_name: name,
77      attributes:    attributes,
78      activity_sid:  activity_by_name('Idle').sid
79    )
80  end
81
82  def activity_by_name(name)
83    client.workspaces(@workspace_sid).activities.list(friendly_name: name).first
84  end
85
86  def create_task_queues
87    reservation_activity_sid = activity_by_name('Reserved').sid
88    assignment_activity_sid  = activity_by_name('Busy').sid
89
90    voice_queue = create_task_queue('Voice', reservation_activity_sid,
91                                    assignment_activity_sid,
92                                    "products HAS 'ProgrammableVoice'")
93
94    sms_queue = create_task_queue('SMS', reservation_activity_sid,
95                                  assignment_activity_sid,
96                                  "products HAS 'ProgrammableSMS'")
97
98    all_queue = create_task_queue('All', reservation_activity_sid,
99                                  assignment_activity_sid, '1==1')
100
101    { voice: voice_queue, sms: sms_queue, all: all_queue }
102  end
103
104  def create_task_queue(name, reservation_sid, assignment_sid, target_workers)
105    client.workspaces(@workspace_sid).task_queues.create(
106      friendly_name: name,
107      reservation_activity_sid: reservation_sid,
108      assignment_activity_sid: assignment_sid,
109      target_workers: target_workers
110    )
111  end
112
113  def create_workflow
114    queues = create_task_queues
115    config = workflow_config(queues)
116
117    client.workspaces(@workspace_sid).workflows.create(
118      configuration: config.to_json,
119      friendly_name: WORKFLOW_NAME,
120      assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
121      fallback_assignment_callback_url: ASSIGNMENT_CALLBACK_URL,
122      task_reservation_timeout: WORKFLOW_TIMEOUT
123    )
124  end
125
126  def workspace_sid
127    @workspace_sid || 'no_workspace_yet'
128  end
129
130  def workflow_config(queues)
131    default_target = default_rule_target(queues[:all].sid)
132
133    {
134      task_routing: {
135        filters: [
136          {
137            expression: 'selected_product=="ProgrammableVoice"',
138            targets: [
139              rule_target(queues[:voice].sid),
140              default_target
141            ]
142          },
143          {
144            expression: 'selected_product=="ProgrammableSMS"',
145            targets: [
146              rule_target(queues[:sms].sid),
147              default_target
148            ]
149          }
150        ],
151        default_filter: default_target
152      }
153    }
154  end
155
156  def rule_target(sid)
157    { queue: sid, priority: 5, timeout: QUEUE_TIMEOUT }
158  end
159
160  def default_rule_target(sid)
161    {
162      queue: sid,
163      priority: 1,
164      timeout: QUEUE_TIMEOUT,
165      expression: '1==1'
166    }
167  end
168end

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, and a key they can press in order to select one. The Gather verb allows us to capture the user's key press.

Handle Incoming Call

lib/twiml_generator.rb

1module TwimlGenerator
2  def self.generate_gather_product(callback_url)
3    response = Twilio::TwiML::VoiceResponse.new
4    gather = Twilio::TwiML::Gather.new(num_digits: 1,
5                                       action: callback_url,
6                                       method: 'POST')
7    gather.say 'Welcome to the Twilio support line!'
8    gather.say 'To get specialized help with programmable voice press 1, '\
9      'or press 2 for programmable SMS'
10
11    response.append(gather)
12    response.to_s
13  end
14
15  def self.generate_task_enqueue(selected_product)
16    enqueue = Twilio::TwiML::Enqueue.new(nil, workflow_sid: WorkspaceInfo.instance.workflow_sid)
17    enqueue.task "{\"selected_product\": \"#{selected_product}\"}"
18
19    response = Twilio::TwiML::VoiceResponse.new
20    response.append(enqueue)
21    response.to_s
22  end
23
24  def self.generate_confirm_message(status)
25    response = Twilio::TwiML::MessagingResponse.new
26    response.message(body: "Your status has changed to #{status}")
27    response.to_s
28  end
29end

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 them 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

lib/twiml_generator.rb

1module TwimlGenerator
2  def self.generate_gather_product(callback_url)
3    response = Twilio::TwiML::VoiceResponse.new
4    gather = Twilio::TwiML::Gather.new(num_digits: 1,
5                                       action: callback_url,
6                                       method: 'POST')
7    gather.say 'Welcome to the Twilio support line!'
8    gather.say 'To get specialized help with programmable voice press 1, '\
9      'or press 2 for programmable SMS'
10
11    response.append(gather)
12    response.to_s
13  end
14
15  def self.generate_task_enqueue(selected_product)
16    enqueue = Twilio::TwiML::Enqueue.new(nil, workflow_sid: WorkspaceInfo.instance.workflow_sid)
17    enqueue.task "{\"selected_product\": \"#{selected_product}\"}"
18
19    response = Twilio::TwiML::VoiceResponse.new
20    response.append(enqueue)
21    response.to_s
22  end
23
24  def self.generate_confirm_message(status)
25    response = Twilio::TwiML::MessagingResponse.new
26    response.message(body: "Your status has changed to #{status}")
27    response.to_s
28  end
29end

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 using the WorkspaceConfig class when the application is initialized. 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, let's 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

app/controllers/callback_controller.rb

1class CallbackController < ApplicationController
2  skip_before_filter :verify_authenticity_token
3
4  def assignment
5    instruction = {
6      instruction: 'dequeue',
7      post_work_activity_sid: WorkspaceInfo.instance.post_work_activity_sid
8    }
9
10    render json: instruction
11  end
12
13  def events
14    event_type = params[:EventType]
15
16    if ['workflow.timeout', 'task.canceled'].include?(event_type)
17      task_attributes = JSON.parse(params[:TaskAttributes])
18
19      MissedCall.create(
20        selected_product: task_attributes['selected_product'],
21        phone_number: task_attributes['from']
22      )
23
24      redirect_to_voicemail(task_attributes['call_sid']) if event_type == 'workflow.timeout'
25    elsif event_type == 'worker.activity.update' &&
26          params[:WorkerActivityName] == 'Offline'
27
28      worker_attributes = JSON.parse(params[:WorkerAttributes])
29      notify_offline_status(worker_attributes['contact_uri'])
30    end
31
32    render nothing: true
33  end
34
35  private
36
37  def redirect_to_voicemail(call_sid)
38    email         = ENV['MISSED_CALLS_EMAIL_ADDRESS']
39    message       = 'Sorry, All agents are busy. Please leave a message. We\'ll call you as soon as possible'
40    url_message   = { Message: message }.to_query
41    redirect_url  =
42      "http://twimlets.com/voicemail?Email=#{email}&#{url_message}"
43
44    client.calls(call_sid).update(url: redirect_url)
45  end
46
47  def notify_offline_status(phone_number)
48    message = 'Your status has changed to Offline. Reply with '\
49              '"On" to get back Online'
50    client.messages.create(
51      to: phone_number,
52      from: ENV['TWILIO_NUMBER'],
53      body: message
54    )
55  end
56
57  def client
58    Twilio::REST::Client.new(ENV['TWILIO_ACCOUNT_SID'], ENV['TWILIO_AUTH_TOKEN'])
59  end
60end

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 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

app/controllers/callback_controller.rb

1class CallbackController < ApplicationController
2  skip_before_filter :verify_authenticity_token
3
4  def assignment
5    instruction = {
6      instruction: 'dequeue',
7      post_work_activity_sid: WorkspaceInfo.instance.post_work_activity_sid
8    }
9
10    render json: instruction
11  end
12
13  def events
14    event_type = params[:EventType]
15
16    if ['workflow.timeout', 'task.canceled'].include?(event_type)
17      task_attributes = JSON.parse(params[:TaskAttributes])
18
19      MissedCall.create(
20        selected_product: task_attributes['selected_product'],
21        phone_number: task_attributes['from']
22      )
23
24      redirect_to_voicemail(task_attributes['call_sid']) if event_type == 'workflow.timeout'
25    elsif event_type == 'worker.activity.update' &&
26          params[:WorkerActivityName] == 'Offline'
27
28      worker_attributes = JSON.parse(params[:WorkerAttributes])
29      notify_offline_status(worker_attributes['contact_uri'])
30    end
31
32    render nothing: true
33  end
34
35  private
36
37  def redirect_to_voicemail(call_sid)
38    email         = ENV['MISSED_CALLS_EMAIL_ADDRESS']
39    message       = 'Sorry, All agents are busy. Please leave a message. We\'ll call you as soon as possible'
40    url_message   = { Message: message }.to_query
41    redirect_url  =
42      "http://twimlets.com/voicemail?Email=#{email}&#{url_message}"
43
44    client.calls(call_sid).update(url: redirect_url)
45  end
46
47  def notify_offline_status(phone_number)
48    message = 'Your status has changed to Offline. Reply with '\
49              '"On" to get back Online'
50    client.messages.create(
51      to: phone_number,
52      from: ENV['TWILIO_NUMBER'],
53      body: message
54    )
55  end
56
57  def client
58    Twilio::REST::Client.new(ENV['TWILIO_ACCOUNT_SID'], ENV['TWILIO_AUTH_TOKEN'])
59  end
60end

See how to allow Workers change their availability status

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

app/controllers/message_controller.rb

1class MessageController < ApplicationController
2  skip_before_filter :verify_authenticity_token
3
4  def incoming
5    command     = params['Body'].downcase
6    from_number = params['From']
7
8    if command == 'off'
9      status = 'Offline'
10      activity_sid = WorkspaceInfo.instance.offline_activity_sid
11    else
12      status = 'Idle'
13      activity_sid = WorkspaceInfo.instance.idle_activity_sid
14    end
15
16    worker_sid = WorkspaceInfo.instance.workers[from_number][:sid]
17    client
18      .workspaces(WorkspaceInfo.instance.workspace_sid)
19      .workers(worker_sid)
20      .fetch
21      .update(activity_sid: activity_sid)
22
23    render xml: TwimlGenerator.generate_confirm_message(status)
24  end
25
26  private
27
28  def client
29    client_instance = Twilio::REST::Client.new(
30      ENV['TWILIO_ACCOUNT_SID'],
31      ENV['TWILIO_AUTH_TOKEN']
32    )
33
34    client_instance.taskrouter.v1
35  end
36end

Congratulations! You finished this tutorial. As you can see, using Twilio's TaskRouter is quite simple.

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