goc is a comprehensive coverage testing system for The Go Programming Language, especially for some complex scenarios, like system testing code coverage collection and
2. use `goc build` to build the target service, and run the generated binary. Here let's take the [simple-go-server](https://github.com/CarlJi/simple-go-server) project as example:
### Show Code Coverage Change at Runtime in Vscode
We provide a vscode extension - [Goc Coverage](https://marketplace.visualstudio.com/items?itemName=lyyyuna.goc) which can show highlighted covered source code at runtime.
1. To understand the execution details of goc tool, you can use the `--debug` flag. Also we appreciate if you can provide such logs when submitting a bug to us.
2. By default, the covered service will listen a random port in order to communicate with the goc server. This may not be suitable in [docker](https://docs.docker.com/engine/reference/commandline/run/#publish-or-expose-port--p---expose) or [kubernetes](https://kubernetes.io/docs/concepts/services-networking/service/#defining-a-service) environment since the port must be exposed explicitly in order to be accessible by others in such environment. For this kind of scenario, you can use `--agentport` flag to specific a fixed port when calling `goc build` or `goc install`.
4. The coverage data is stored on each covered service side, so if one service needs to restart during test, this service's coverage data will be lost. For this case, you can use following steps to handle:
1. Before the service restarts, collect coverage with `goc profile -o a.cov`
2. After service restarted and test finished, collect coverage again with `goc profile -o b.cov`
