Command service API is stuck at first run

[jinlinGuan]

🐞 Bug Report

Affected Services

The issue is located in: core-command

Is this a regression?

yes, only happen in master branch

Description and Minimal Reproduction

When the command service starts, the first time of executing http://localhost:48082/api/v1/device will be stuck.

1. download the nightly-build docker-compose file
   https://github.com/edgexfoundry/developer-scripts/blob/master/releases/nightly-build/compose-files/docker-compose-nexus-redis-no-secty.yml
2. use docker-compose up
   docker-compose -f docker-compose-nexus-redis-no-secty.yml up -d
3. use curl to send request to http://localhost:48082/api/v1/device
   curl http://localhost:48082/api/v1/device
4. the request is stuck

🔥 Exception or Error

There is no error log in edgex-core-command container.

🌍 Your Environment

Deployment Environment:

EdgeX Version:
Master

Anything else relevant?
Cancel the curl request, and send it again, the request works properly.
Also, this issue could be reproduced by simply restarting command service.

1. docker-compose -f docker-compose-nexus-redis-no-secty.yml restart command
2. send curl request again

[jinlinGuan]

This issue currently causes failure in blackbox-testing.

[brandonforster]

This might be a regression introduced by #2370 somewhere in the URLClient code. I don't have any insight or theories beyond that.

[michaelestrin]

This looks to me like a variation of the original issue that led us down the refactoring path.

Possibly newly introduced retry is not working as expected?

Assigned to @brandonforster for investigation/solution.

[brandonforster]

It looks like logging is throwing an error retrieving its configuration from Consul. I'd say there's two issues here:

1. Why is logging not able to retrieve its configuration?
2. Why is logging not starting making command stop, shutdown, and then restart over and over and over?

[brandonforster]

I believe I have identified the issue in contracts. Submitting a PR now, I'll use this issue number to update the core-contracts version.

[michaelestrin]

Closed by edgexfoundry/go-mod-core-contracts#220

[brandonforster]

Reopening, adding a PR to incorporate those changes into the codebase and fix the BB tests.