fix: gcp retriever is able get the updated flags file

[jferrl]

Description

What was the problem?

It was not possible to use an instance of gcstorageretriever.Retriever{} since it is only able to get the file on the initial bootstrap of go-feature-flag instance. After feature flag client is up and running, the internal flags cache is no longer updated when gcstorageretriever is used.

How it is resolved?

The issue has been resolved avoiding the use of the file reader as a field of Retriever. So, after the first bootstrap of Retriever the file reader was closed because the code closes the reader after done reading. If we try out another call to Retriever.Retrieve() the reader is not nil and it was closed, so that, it was not able to get the updated file. In that case, we could see some log trace like:

fmt.Errorf("unable to read from GCP Object %s in Bucket %s, error: %s", retriever.Bucket, retriever.Object, err)

How can we test the change?

• Unit tests
• Example script using gcstorageretriever.Retriever{}

Changes include

• Bugfix (non-breaking change that solves an issue)
• New feature (non-breaking change that adds functionality)
• Breaking changes (change that is not backward-compatible and/or changes current functionality)

Closes issue(s)

#310

Checklist

• I have tested this code
• I have added unit test to cover this code
• I have updated the documentation (README.md and /docs)
• I have followed the contributing guide

[coveralls]

Coverage increased (+0.3%) to 95.096% when pulling d40639c on jferrl:fix/gcs-retriever into b7fd690 on thomaspoignant:main.

[thomaspoignant]

Don't worry about the linting issue, I will fix it in another PR and will works for you.

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
2.0% Duplication

[jferrl]

@thomaspoignant PR able to merge! 🚀

[thomaspoignant]

Thanks a lot for you contribution @jferrl
Sorry for the delay in the review.

I will release a new version with this fix today.