Exception while invoking method 'createDirectMessage' Error: Match error: Expected string, got null

Description:

Randomly I am seeing the title error in the log.

Steps to reproduce:

Not sure yet what is the cause.

Expected behavior:

No errors.

Actual behavior:

createDirectMessage error

Server Setup Information:

• Version of Rocket.Chat Server: 4.1.2
• Operating System: Ubuntu 20.04
• Deployment Method: tar rocketchat official site method
• Number of Running Instances: 1
• DB Replicaset Oplog: Enabled
• NodeJS Version: v12.22.1
• MongoDB Version: 4.2.17
• Commit Hash: 2aba8d2d82
• free storage space
• free inode space

Additional context

• Was happening before 4.1.2 update according the logs.
• And just appeared after 3.18.1 update ( NodeJS Version: 12.22.1 - x64, MongoDB Version: 4.0.27, MongoDB Engine: mmapv1, Commit Hash: 73ab3c26a7), according to the logs

Relevant logs:

rockechat journal log:

Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]: Exception while invoking method 'createDirectMessage' Error: Match error: Expected string, got null
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at check (packages/check/match.js:36:17)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at createDirectMessage (server/methods/createDirectMessage.js:12:2)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at MethodInvocation.createDirectMessage (server/methods/createDirectMessage.js:94:10)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at MethodInvocation.methodsMap.<computed> (app/lib/server/lib/debug.js:66:34)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at maybeAuditArgumentChecks (packages/ddp-server/livedata_server.js:1771:12)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at packages/ddp-server/livedata_server.js:719:19
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at Meteor.EnvironmentVariable.EVp.withValue (packages/meteor.js:1234:12)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at packages/ddp-server/livedata_server.js:717:46
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at Meteor.EnvironmentVariable.EVp.withValue (packages/meteor.js:1234:12)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at packages/ddp-server/livedata_server.js:715:46
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at new Promise (<anonymous>)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at Session.method (packages/ddp-server/livedata_server.js:689:23)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at packages/ddp-server/livedata_server.js:559:43
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]: Sanitized and reported to the client as: errorClass [Error]: Match failed [400]
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at errorClass.<anonymous> (packages/check/match.js:91:27)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at new errorClass (packages/meteor.js:655:17)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at check (packages/check/match.js:36:17)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at createDirectMessage (server/methods/createDirectMessage.js:12:2)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at MethodInvocation.createDirectMessage (server/methods/createDirectMessage.js:94:10)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at MethodInvocation.methodsMap.<computed> (app/lib/server/lib/debug.js:66:34)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at maybeAuditArgumentChecks (packages/ddp-server/livedata_server.js:1771:12)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at packages/ddp-server/livedata_server.js:719:19
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at Meteor.EnvironmentVariable.EVp.withValue (packages/meteor.js:1234:12)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at packages/ddp-server/livedata_server.js:717:46
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at Meteor.EnvironmentVariable.EVp.withValue (packages/meteor.js:1234:12)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at packages/ddp-server/livedata_server.js:715:46
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at new Promise (<anonymous>)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at Session.method (packages/ddp-server/livedata_server.js:689:23)
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:     at packages/ddp-server/livedata_server.js:559:43 {
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:   isClientSafe: true,
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:   error: 400,
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:   reason: 'Match failed',
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:   details: undefined,
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]:   errorType: 'Meteor.Error'
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]: }
Nov 22 10:44:24 ip-172-31-42-134 rocketchat[570]: undefined undefined

Start at server/methods/createDirectMessage.js, especially the validation around line 12 and the method call around line 94 shown in the stack trace. Trace which createDirectMessage argument is null and determine the triggering request or data state. Done means identifying the cause and preventing the method from producing this match error, with regression coverage if the relevant test location can be found.