I've used NSQ for one of our projects - It is very cool system for handling messaging queues. But I had a very annoying problem - We have more than 5 queues and for each I should start new container of nsq_tail:
version: '3.2' services: nsqtail: image: nsqio/nsq command: /nsq_tail --topic=mytopic1 --lookupd-http-address=nsqlookupd:4161 nsqtail2: image: nsqio/nsq command: /nsq_tail --topic=mytopic2 --lookupd-http-address=nsqlookupd:4161 nsqtail3: image: nsqio/nsq command: /nsq_tail --topic=mytopic3 --lookupd-http-address=nsqlookupd:4161 ...
I know that Docker is "lightweight" system... But not lightweight-enough for running too many containers for simple tasks. So my idea was to make nsq_tail listen for multiple topics at once and write all messages from them. Now I can do simply:
version: '3.2' services: nsqtail: image: soarname/nsq command: /nsq_tail --topic=topic1 --topic=topic2 --topic=topic3 --lookupd-http-address=nsqlookupd:4161
And then in logs I see:
nsqtail_1 | topic1 | test-message-1 nsqtail_1 | topic2 | test-message-2 nsqtail_1 | topic3 | test-message-3
So, if you want use this improvement - just pull my automatically built image from Docker Hub: soarname/nsq or vote for my Pull Request #957.