Send messages from a manager to an agent and client conversation displays error "Exception while invoking method 'sendMessage' TypeError: Cannot read property 'blocker' of undefined"

[soumarcelino]

Description:

This error show when a livechat manager send a message into a running chat

Server Setup Information:

Version of Rocket.Chat Server: 0.60.0-develop
Operating System: Ubuntu 16.10
Deployment Method(snap/docker/tar/etc): all
Number of Running Instances: 1
DB Replicaset Oplog: ?
Node Version: v8.8.1

Steps to Reproduce:

1. A manager enters a live chat with an agent and client.

2. The manager sends a message but no one receives the message.

3. Errors are displayed on the console

Expected behavior:

I hope the manager's message is seen by the agent and the client.

Actual behavior:

The manager's message is not sent to anyone.

Relevant logs:

I20171123-14:43:57.583(-3)? Exception while invoking method 'sendMessage' TypeError: Cannot read property 'blocker' of undefined
I20171123-14:43:57.679(-3)? at DDPCommon.MethodInvocation.sendMessage (/home/marcelino/Rocket.Chat/.meteor/local/build/programs/server/packages/rocketchat_lib.js:13912:60)
I20171123-14:43:57.679(-3)? at DDPCommon.MethodInvocation.methodsMap.(anonymous function) (/home/marcelino/Rocket.Chat/.meteor/local/build/programs/server/packages/rocketchat_lib.js:1265:26)
I20171123-14:43:57.679(-3)? at DDPCommon.MethodInvocation.methodMap.(anonymous function) (packages/rocketchat_monitoring.js:2731:30)
I20171123-14:43:57.680(-3)? at maybeAuditArgumentChecks (/home/marcelino/Rocket.Chat/.meteor/local/build/programs/server/packages/ddp-server.js:1826:12)
I20171123-14:43:57.680(-3)? at DDP._CurrentMethodInvocation.withValue (/home/marcelino/Rocket.Chat/.meteor/local/build/programs/server/packages/ddp-server.js:892:126)
I20171123-14:43:57.680(-3)? at Meteor.EnvironmentVariable.EVp.withValue (packages/meteor.js:1184:15)
I20171123-14:43:57.680(-3)? at DDPServer._CurrentWriteFence.withValue (/home/marcelino/Rocket.Chat/.meteor/local/build/programs/server/packages/ddp-server.js:892:98)
I20171123-14:43:57.681(-3)? at Meteor.EnvironmentVariable.EVp.withValue (packages/meteor.js:1184:15)
I20171123-14:43:57.681(-3)? at Promise (/home/marcelino/Rocket.Chat/.meteor/local/build/programs/server/packages/ddp-server.js:892:46)
I20171123-14:43:57.681(-3)? at new Promise (:null:null)
I20171123-14:43:57.681(-3)? at Session.method (/home/marcelino/Rocket.Chat/.meteor/local/build/programs/server/packages/ddp-server.js:865:23)
I20171123-14:43:57.681(-3)? at /home/marcelino/Rocket.Chat/.meteor/local/build/programs/server/packages/ddp-server.js:744:85

[soumarcelino]

This problem also occurs in version 0.59.3 in Live Chat