Remove the hard-coded writeConcern

[raymondfeng]

{w: 1} is not always valid.
See https://docs.mongodb.com/manual/reference/write-concern/#write-concern

Description

When performing a PUT operation from Loopback app to compose for mongo instance, it throws exception:

{"error": {
   "name": "MongoError",
   "status": 500,
   "message": "w: 'majority' is the only valid write concern when writing to config server replica sets, got: { w: 1, wtimeout: 0 }",
   "ok": 0,
   "errmsg": "w: 'majority' is the only valid write concern when writing to config server replica sets, got: { w: 1, wtimeout: 0 }",
   "code": 2
}}

Related issues

• None

Checklist

• New tests added or existing tests modified to cover all changes
• Code conforms with the style
  guide

[jannyHou]

One nitpick to get CI commit lint pass:

242f560 - Remove the hard-coded writeConcern: line 4 longer than 72 characters.

[raymondfeng]

@jannyHou Thanks for the review. I don't think it makes sense to split the http url in 2 lines. I'll use the admin right to merge it.

[kequarles]

This pull request is associated with Bluemix support ticket https://jazzop27.rtp.raleigh.ibm.com:9443/ccm/web/projects/CloudOE#action=com.ibm.team.workitem.viewWorkItem&id=484915, which I have taken ownership of to monitor (in my current role as Gateway Director squad rep for the support interrupt role), as Raymond does not have access to jazzop27 (RTC repository). @raymondfeng What can be communicated in the ticket (=> to the customer by support) regarding when the customer can expect to benefit from your fix?

[raymondfeng]

@kequarles The PR should fix the issue described above as reported by the customer.

[kequarles]

Per Slack conversation, Raymond confirmed that the fix is available in NPM, and the customer can obtain it by executing "npm i loopback-connector-mongodb@^3.2.0 --save" to update the dependency for the loopback app. I've updated the ticket with this info, for support to relay to the customer.