Debug Mode

Introduction

Debugging why a batch has failed by making changes to the configuration and rerunning can be fiddly. To help with debugging in certain situations, ReSim has developed a debug mode which can be used to interact with your image in a live environment.

Prerequisites

• The ReSim CLI must be installed on your local device
• Your image must include a shell (e.g. sh or bash) and the sleep command.
• You need an experience ID or name
• You also need a batch name or a build ID

Running a debug session

Run the debug command:

resim debug --project <project-id> --build <build-id> --experience my-test-data

In the background, ReSim will launch a new ephemeral environment and run your build image in it. The experience data will be available (read-only) in /tmp/resim/inputs as in a standard batch.

If your image is very large, it can take a few minutes to set up the debug environment.

By default, the command that runs in your container will be sh, but you can override this by setting the --command flag on the debug command.

Once the batch is running, you will be dropped into a shell. From this shell, you can run commands as normal to inspect the environment and configuration.

For example, you could:

• check dependencies are installed
• check the input data in /tmp/resim/inputs is present and structured correctly
• run entrypoint scripts to see immediate output and debug errors

The debug batch will run for 1 hour or your experience's timeout setting, whichever is longer. After the timeout or when you exit the shell by running exit or pressing Ctrl-D, ReSim will terminate the debug batch.

Any files you write to /tmp/resim/outputs will be uploaded as in a standard batch for later inspection.

Debug mode for Multi Container Builds

If you have a multi-container build setup, which is described by a docker compose file, you can specify the container you want to bash in using the --container flag, which should be the container_name parameter that you specify in the compose file for a service.