Slack import fails when encountering file upload

[zw42]

Rocket.Chat Version: 0.57.1 (Ubuntu snap)
Running Instances: 1
DB Replicaset OpLog: Enabled
Node Version: v4.8.1

Have an issue when importing from Slack: causes an exception when it needs to upload a file. From the log:

snap[9263]: Exception in defer callback: TypeError: Cannot read property 'get' of undefined snap[9263]: at _class.uploadFile (/snap/rocketchat-server/812/programs/server/packages/rocketchat_importer.js:325:24) snap[9263]: at /snap/rocketchat-server/812/programs/server/packages/rocketchat_importer-slack.js:555:20 snap[9263]: at Array.forEach (native) snap[9263]: at /snap/rocketchat-server/812/programs/server/packages/rocketchat_importer-slack.js:458:22 snap[9263]: at Array.forEach (native) snap[9263]: at [object Object].<anonymous> (/snap/rocketchat-server/812/programs/server/packages/rocketchat_importer-slack.js:456:32) snap[9263]: at packages/dispatch_run-as-user.js:211:14 snap[9263]: at [object Object]._.extend.withValue (packages/meteor.js:1122:17) snap[9263]: at Object.Meteor.runAsUser (packages/dispatch_run-as-user.js:210:33) snap[9263]: at /snap/rocketchat-server/812/programs/server/packages/rocketchat_importer-slack.js:442:13 snap[9263]: at Array.forEach (native) snap[9263]: at /snap/rocketchat-server/812/programs/server/packages/rocketchat_importer-slack.js:440:34 snap[9263]: at [object Object]._.extend.withValue (packages/meteor.js:1122:17) snap[9263]: at packages/meteor.js:445:45

This issue was not present in 0.56.0 (using the same Slack import file).

[graywolf336]

@sampaiodiego @rodrigok this is broke because of the change to file uploads.

[sampaiodiego]

@graywolf336 yes, it looks like.

@zw42 what file upload storage are you using?

[zw42]

@sampaiodiego using GridFS, also tried FileSystem but the same issue persisted