Load sdk version from buildinfo

[Yang-33]

Currently, line-bot-sdk-go embeds the library version defined in version.go as the user-agent, so version.go is updated manually or forcibly at release time to avoid manual operation. And we define a github workflow to push tag forcibly to automate (1) updating version.go and (2)fix git tag. Because of this, GitHub's branch protection cannot be used. (we can solve this by using PAT, but we don't want to use it)

Since Go 1.18, https://pkg.go.dev/debug/buildinfo has been provided. By using runtime/debug, library(like line-bot-sdk-go) can obtain the library's own version from the runtime of the library user. Since the latest version of line-bot-sdk-go only supports Go 1.22 and above, this feature should be usable.

In the user's environment, the version of line-bot-sdk-go is retrieved from buildinfo only once in runtime. There's no point in recalculating it each time since the same value should be obtained every time.

Excluding meaningless mocks, tests in this repository cannot be written. I created minimum example for this patch.

• https://github.com/Yang-33/line-bot-sdk-go-521-lib
• https://github.com/Yang-33/line-bot-sdk-go-521-app

[kkdai]

It seems GetVersion() cannot retrieval github.com/line/line-bot-sdk-go build info. only itself deps.

Have you ever try it?

[Yang-33]

I created minimum samples for this case. it worked as expected.

About lib repository

https://github.com/Yang-33/line-bot-sdk-go-521-lib

This provides simple http-client calling debug.ReadBuildInfo() internally. You can consider this as a repository similar to line-bot-sdk-go with this patch.

Below app uses this. (or you can use this library in your app)

about app repository

https://github.com/Yang-33/line-bot-sdk-go-521-app

This just uses https://github.com/Yang-33/line-bot-sdk-go-521-lib (lib repository like line-bot-sdk-go), and other libraries.

When the app uses library provided in https://github.com/Yang-33/line-bot-sdk-go-521-lib, it shows all dependencies the app uses.

like

=== All Dependencies ===
- github.com/Yang-33/line-bot-sdk-go-521-lib v0.1.0
- github.com/sirupsen/logrus v1.9.0
- golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8
========================

app calls lib, and lib shows all dependencies in app.

Therefore, I believe this change is working as expected. In the user app, line-bot-sdk-go can obtain its version from buildinfo.

I believe we no longer need to write the version in version.go in line-bot-sdk-go explicitly.

[kkdai]

LGTM, I don't have any more question. Thank you.

[Yang-33]

Thank you for your review!