fix(download): use setMethod('POST') for SPARQL wrapper

[Prakhar54-byte]

Resolves #69

Using direct attribute assignment on SPARQLWrapper (sparql.method = 'POST') is silently ignored by the wrapper, which defaults to GET. Large SPARQL queries (e.g. from collection endpoints) then exceed GET URL-length limits.

This PR uses the correct setMethod('POST') API, and updates the DummySPARQL test stub to mock the method appropriately.

Summary by CodeRabbit

• Bug Fixes
  • Improved how POST-based SPARQL queries are configured, helping download requests work more reliably.
  • Updated test support for the SPARQL client so local test runs remain compatible when the external library is unavailable.

[coderabbitai]

📝 Walkthrough

Walkthrough

The _query_sparql_endpoint function now configures the SPARQL request method via sparql.setMethod("POST") instead of directly setting the method attribute. The test double DummySPARQL in conftest.py adds a matching setMethod method to support this change.

Changes

SPARQL POST Method Fix

Layer / File(s)	Summary
Switch to setMethod call and update test stub databusclient/api/download.py, tests/conftest.py	Replaces direct method attribute assignment with sparql.setMethod("POST") and adds a corresponding setMethod method to the fake SPARQLWrapper used in tests.

Estimated code review effort: 1 (Trivial) | ~3 minutes

Possibly related issues

• bug:sparql.method = "POST" silently ignored — SPARQL queries always use GET  #69: This issue reports the same bug where the POST method needs to be set via setMethod("POST") rather than direct attribute assignment, which this PR fixes.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description summarizes the fix and issue, but it omits the required type-of-change and checklist sections from the template.	Add the template sections for Type of change and Checklist, including test/ruff confirmation and any documentation or self-review details.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly states the SPARQL wrapper POST method fix and matches the main code change.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}