feat(DX-3233): Bulk publish/unpublish query params, api_version tests, and robust error handling

[OMpawar-21]

Title

feat(DX-3233): Bulk publish/unpublish query params, api_version tests, and robust error handling

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Summary

• DX-3233: Send skip_workflow_stage_check and approvals as query parameters (not headers) for bulk publish/unpublish.
• Integration tests: Add bulk tests with flags (3a/4a), with api_version 3.2 (3b/4b), a helper for test data, and stronger assertions and error handling (3a, 4a, 3b, 4b, 4c).
• Release: Version bump and CHANGELOG entry.

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1. Bulk publish/unpublish: headers → query params (DX-3233)

BulkPublishService.cs

• skip_workflow_stage_check and approvals are no longer set as headers.
• They are set as query parameters via AddQueryResource("skip_workflow_stage_check", "true") and AddQueryResource("approvals", "true").
• BulkUnpublishService already used query params; no change.

Unit tests

• BulkPublishServiceTest.cs: Assertions for these two flags use QueryResources instead of Headers; test names updated to "Query Parameter".
• BulkUnpublishServiceTest.cs: Same (Headers → QueryResources).
• BulkOperationServicesTest.cs: All checks for these flags (Test004, Test006, Test007, Test008) use QueryResources instead of Headers.

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2. Integration tests – bulk operations (Contentstack015_BulkOperationTest.cs)

New/updated tests

• Test003a: Bulk publish with skipWorkflowStage: true and approvals: true.
• Test004a: Bulk unpublish with skipWorkflowStage: true and approvals: true.
• Test003b: Bulk publish with same flags and api_version 3.2 (header).
• Test004b: Bulk unpublish with same flags and api_version 3.2 (header).
• Test004c: Negative test – bulk unpublish with invalid data (empty entries, non-existent env); expects ContentstackErrorException and asserts non-success status and error message.

Helper

• EnsureBulkTestContentTypeAndEntriesAsync(): Ensures bulk_test_content_type and at least one entry exist so bulk tests can run in any order.

Assertions and error handling

• FailWithError(operation, ex): Centralized failure reporting; for ContentstackErrorException includes HTTP status, ErrorCode, and API message.
• Test003a, Test004a, Test003b, Test004b: Explicit Assert.AreEqual(HttpStatusCode.OK, response.StatusCode) and descriptive IsSuccessStatusCode messages; catch blocks use FailWithError.
• Usings: System.Net, Contentstack.Management.Core.Exceptions.

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3. Release

• Directory.Build.props: Version bumped (e.g. 0.6.1 → 0.7.0).
• CHANGELOG.md: New version entry for bulk query params, integration tests, and error-handling improvements.

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Testing

• Unit tests: BulkPublishServiceTest, BulkUnpublishServiceTest, BulkOperationServicesTest (bulk-related) pass.
• Integration tests: Test003a, Test004a, Test003b, Test004b, Test004c pass against a stack with required setup.

Checklist

• Code follows project conventions.
• Unit tests updated for query-param behavior.
• Integration tests cover bulk with flags, api_version 3.2, and invalid data.
• CHANGELOG and version updated.