dep check

This repo contains a tool to validate imports inside Go monorepos, and to run tests selectively based on changed files and imports structure.

Installation

go install github.com/moveaxlab/dep-check

Configuration

This tool distingueshes between 4 types of packages:

• external is used for vendored external dependencies and other stuff we don't care about. We ignore them, anyone can import them.
• common are packages that contain shared code between services. Common packages can import from each other, and services can import from common packages.
• service are packages containing code for a component or microservice. They can import from common packages and from external packages, and cannot import code from other services.
• utility are packages that contain utility scripts that should only be run locally. They can import from wherever they want, and no one can import them.

To configure the tool, create a dep-check.yaml file in the root of your Go project, and fill its contents like this:

module_name: github.com/moveaxlab/dep-check  # the module name of your project
folders:
  external:
    - external/*
  common:
    - common/src/*
    - models/*
  utility:
    - scripts
    - common/scripts
  service:
    - service/*

The folders configuration specifies which folders fall in which category. All folders are specified from the root of your Go project. You can use the * symbols as a wildcard: this instructs dep-check to treat each folder under the specified path as a separate package.

An example is worth a thousand words. Given the above configuration and the following directory structure:

common/
  scripts/
    script_1/
    script_2/
  src/
    config/
    postgres/
    kafka/
      consumer/
      producer/
external/
  dep_1/
  dep_2/
models/
  auth/
  common/
  order/
  product/
scripts/
  script_3/
  script_4/
service/
  service_1/
  service_2/
  service_3/
other_package/

dep-check will identify these packages:

• external packages:
  • external
  • other_package
• utility packages:
  • common/scripts
  • scripts
• common packages:
  • common/src/config
  • common/src/postgres
  • common/src/kafka
  • models/auth
  • models/common
  • models/order
  • models/product
• service packages:
  • service/service_1
  • service/service_2
  • service/service_3

All packages that are not matched by an explicit rule will fall under the external category. You can add the '*' catch all to the service category to treat all other packages as services.

If the root of your repo is not the same as the root of your Go project, you can add the root_dir configuration option to specify the path from the root of the repo to the root of your Go project.

You only need this to run tests selectively when using git.

You can now run dep-check from the root of your Go project.

Validating project structure

dep-check validate

Running tests selectively

Get a list of changed files and feed it to dep-check:

readarray -t PACKAGES < <(git diff --name-only "${TARGET_BRANCH}...${CURRENT_BRANCH}" | dep-check changed-packages)

You can also run tests on staged files:

readarray -t PACKAGES < <(git diff --staged --name-only | dep-check changed-packages)

Then, iterate over the changed packages and run your tests:

for PACKAGE in "${PACKAGES[@]}"
do
  go test  "$PACKAGE"
done