Add HttpOperator JSON serialization support with tests

[a-chumagin]

This PR resolved issue #370

Add HttpOperator JSON serialization support with tests

• Add utility function for JSON serialization of HTTP request data
• Add automatic Content-Type header handling for HttpOperator
• Support both dictionary and string JSON inputs with validation
• Add comprehensive tests for HttpOperator serialization
• Add YAML examples for HTTP operator configuration

Additionally:

• Fix Makefine

Tested by:

1. Running Airflow with DagFactory
2. Executing a DAG with HttpOperator tasks
3. Verifying request body format with an echo-server
4. Confirming proper Content-Type headers are set

[tatiana]

Hi @a-chumagin, thank you very much for implementing this.

It seems several checks in the CI are currently failing. An example of the last run:
https://github.com/astronomer/dag-factory/actions/runs/14057622752/job/39360581792?pr=382

Please, could you fix them?

The contributing guide may help:
https://astronomer.github.io/dag-factory/latest/contributing/howto/#run-integration-tests

Plase, let us know if you have any questions.

[a-chumagin]

@tatiana hello!
It looks like dependences issues between airflow and http libs. I try to fix this.
Also for some reason could of failed tests locally and here are different .

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 89.65517% with 3 lines in your changes missing coverage. Please review.

Project coverage is 93.87%. Comparing base (d5373cd) to head (73c6409).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
dagfactory/dagbuilder.py	82.35%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #382      +/-   ##
==========================================
- Coverage   94.01%   93.87%   -0.14%     
==========================================
  Files          11       11              
  Lines         886      915      +29     
==========================================
+ Hits          833      859      +26     
- Misses         53       56       +3     

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[pankajastro]

Looking great, thanks for implementing this!

[a-chumagin]

HTTP Operator Compatibility

Airflow Version Challenges

Supporting HTTP operators across multiple Airflow versions required handling differences in operator naming and import paths:

• Airflow 2.0 - providers-http 4.10.0: SimpleHttpOperator in airflow.providers.http.operators.http
• Airflow providers-http >= 4.11.0: HttpOperator (renamed)

To ensure compatibility, we implemented dynamic imports:

try:
    from airflow.providers.http.operators.http import HttpOperator
    HTTP_OPERATOR_CLASS = HttpOperator
except ImportError:
    try:
        from airflow.providers.http.operators.http import SimpleHttpOperator
        HTTP_OPERATOR_CLASS = SimpleHttpOperator
    except ImportError:
        HTTP_OPERATOR_CLASS = None

Generalized Testing

To handle both SimpleHttpOperator and HttpOperator:

1. Parametrized tests were created to work with either operator.
2. Conditional test skipping was implemented for unsupported versions.
3. Dynamic fixture selection was used based on the operator class:

   if HTTP_OPERATOR_PATH == "airflow.providers.http.operators.http.HttpOperator":
       fixture_path = "tests/fixtures/dag_factory_http_operator_task.yml"
   else:
       fixture_path = "tests/fixtures/dag_factory_simple_http_operator_task.yml"

Integration Test Limitations

Integration testing faced the following constraints:

1. Complex CI setup was required to test across multiple Airflow versions.
2. Mock servers or specialized environments were needed to verify HTTP requests.
3. Serialization differences across versions required version-specific assertions.

Unit tests were prioritized to ensure compatibility while minimizing the need for complex integration setups.