[Go] Refactor the codebase of `embed-code-go`

[olena-zmiiova]

As of now, we feel that current Go codebase is mature enough to be reviewed by someone, who hasn't been originally involved into the project. This is needed to ensure the longevity of the code for the years to come — as we expect to use Go-based tooling for a long time.

In the scope of this issue, the following steps should be performed:

1. The review of the existing source code.
2. Identification of issues.
3. Addressing the issues (todo: avoid massive changesets, go small).
4. (if possible) Configuring and enabling the automatic linters to prevent the issues in the future.
5. (optional) Forming a page on wiki on the code style.

The last point needs to be discussed prior to its execution.

[armiol]

@olena-zmiiova @dmytro-kashcheiev I have updated the text of the issue. FYI.

[olena-zmiiova]

After the code analyses, I came out with the following plan of refactoring. Some of the points might be complex, and I'll create other GH issues to complete them.

Code:

1. Function bodies and logic should be easier to read and understand. It should be done package by package.
2. Errors:
   • We don’t need a panic in every case.
   • Consider returning an error instead of just a message for validation.
   • Validate error processing and add where it’s needed.
3. Entrypoint arguments:
   • Update validation code.
   • Use another naming convention (including fields in config .yaml files).
4. Logging:
   • Add logs to make what is happening clear and easier to debug.
   • Add output to a user on a successful run.

Tests:

1. Test files should be placed near project files.
2. Consider using ginkgo and/or gomega libraries.

Documentation:

1. Validate and update project docs/readmes.
2. Add documentation for packages where missed.
3. Add name reference in docs.

CI:

1. Configure run of golangci-lint on PRs.
2. Configure docs generating with godoc (optional).

[olena-zmiiova]

In the scope of an issue, the list of PRs was merged:

• Add linters to check Golang code #44
• Fix issues found by golangci-linter #45
• Refactor cli package and entrypoint #49
• Update UTs for cli package #50
• Refactor fragmentation package #51
• [Go] Refactor embedding package #53
• [Go] Refactor embedding context, fix remaining linter issues #54

The main task of refactoring can be considered as resolved, but here are the possible points to improve the embed-code codebase:

• Improve logging.
• Configure godoc generation.
• GitHub actions should run as a chain: if there are no linter issues and all tests pass, the code should be built into binaries. Currently, the embed-code is built every time on PRs into embed-code-go branch, even if tests or linter has failed.
• Add more test cases to improve the test coverage, and consider using parameterized tests.

Important

Do not forget to rename fields in JxBrowser-Docs/_hugo-site/embed-code-config.yml file before updating the binaries in JxBrowser-Docs. Please, refer to README.md for the new namings.

[alexander-yevsyukov]

@Oleg-Melnik, please transfer this issue to the embed-code-go repository and address it in the near future.