How do I see the logs for Fabric Composer

Question

I would like to view the runtime and client logs generated by Fabric Composer but cannot find them. Can you please provide guidance on how to access the logs?.

Answer 1

Runtime Logs

If you run docker ps -a you should see 3 running docker containers. One of the docker containers will be the chaincode container (where the Composer runtime is executing your logic).

It has a generated name something like: dev-vp0-4968dea9e3a69670235d9283859801ab5df6f18398f15711d6f5426123955f9f

Look for its container id, and then run docker logs <container id> You can follow the logs using docker logs -f

If you are on the Mac you can also view the logs using the Kitematic GUI. Fabric Composer log entries are tagged with [Concerto] (the old codename)

Client Logs

The client-side APIs (written in Node) can also generate logs. Set the DEBUG environment variable to enable debugging. E.g (for Linux and Mac):

export DEBUG=composer:*

INFO and higher log messages will be sent to stdout by default. All logs will also be logged to disk under a ./logs folder.

Please see the docs here: https://fabric-composer.github.io/problems/diagnostics.html