Migrated compute regions to use transport_tpg.SendRequest

[jcromanu]

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compute: migrated `data_source_google_compute_regions` to use direct HTTP rather than a client library

[google-cla]

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[github-actions]

Googlers: For automatic test runs see go/terraform-auto-test-runs.

@rileykarson, a repository maintainer, has been assigned to review your changes. If you have not received review feedback within 2 business days, please leave a comment on this PR asking them to take a look.

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[rileykarson]

Please remediate CLA issues

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 1 file changed, 22 insertions(+), 10 deletions(-))
google-beta provider: Diff ( 1 file changed, 22 insertions(+), 10 deletions(-))

[modular-magician]

Tests analytics

Total tests: 1405
Passed tests: 1314
Skipped tests: 90
Affected tests: 1

Click here to see the affected service packages

• compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

• TestAccComputeRegions_basic

Get to know how VCR tests work

[modular-magician]

🟢 Tests passed during RECORDING mode:
TestAccComputeRegions_basic [Debug log]

🟢 No issues found for passed tests after REPLAYING rerun.

---

🟢 All tests passed!

View the build log or the debug log for each test

[WentaoNi]

The current implementation uses direct type assertions that will cause a panic if the API response does not match the expected structure or if the items list is missing.

Recommendation: Use the "comma-ok" assertion pattern:

var regions []string
if rawItems, ok := res["items"].([]interface{}); ok {
    regions = flattenRegions(rawItems)
}

[WentaoNi]

Add safety checks to ensure region is a map and name is a string before asserting, see example:

magic-modules/mmv1/third_party/terraform/services/compute/data_source_google_compute_instance_template.go

Line 78 in b79f895

if rawItems, ok := res["items"].([]interface{}); ok {

var items []map[string]interface{}
if rawItems, ok := res["items"].([]interface{}); ok {
    for _, rawItem := range rawItems {
        // ...
    }
}

[github-actions]

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