Quick Start

Install the package:

pip install pytest-jsonschema-snapshot

Then you need to configure the library

Choose the option that best suits your project:

# pytest.ini
[pytest]
jsss_dir = __snapshots__               # where to put the schemas
jsss_callable_regex = {class_method=.} # rule for the callable part
jsss_format_mode = on

# pyproject.toml
[tool.pytest.ini_options]
jsss_dir = "__snapshots__"
jsss_callable_regex = "{class_method=.}"
jsss_format_mode = "on"

# setup.cfg
[tool:pytest]
jsss_dir = __snapshots__
jsss_callable_regex = {class_method=.}
jsss_format_mode = on

  • jsss_dir: the name of the folder where the library will save the schemas/originals (always in the same directory as the test that called it).

  • jsss_callable_regex: the rule for interpreting the callable name.

  • jsss_format_mode: “on” (annotate and validate), “safe” (annotate), “off” (disable).

Next, you can use the fixture in your tests:

from pytest_jsonschema_snapshot import SchemaShot

def test_something(schemashot: SchemaShot):
    # There are data - need to validate through the schema
    schemashot.assert_json_match(
        {"key": "value"}, # data for validation / convert to schema
        "test_name"       # name of the schema
    )

    # There is a schema (data is optional) - validate by what is
    schemashot.assert_schema_match(
        {           # schema
            "$schema": "http://json-schema.org/schema#",
            "type": "object",
            "properties": {
                "content": {
                    "type": "object"
                }
            },
            "required": [
                "content"
            ]
        },
        ("test_name", 1) # == `test_name.1` name of the schema
        data={"content": {"key": "value"}} # data for validation (optional)
    )

Names can be passed as a string, int, callable (function or method), or a tuple/array consisting of them.

Callable fields are converted using NameMaker according to the rule specified by jsss_callable_regex. For how to correctly define your own rules, see NameMaker.

Run

pytest --jsss-debug --save-original --schema-update

  • –jsss-debug: by default, the library hides its part of the call stack when raising. This is convenient for debugging your tests, but if the problem is in PJSSS itself - you can pass.

  • –save-original: save the original data on which the validation was performed. Saving occurs when –schema-update, if you run the schema update without this attribute, the old original data will be deleted without saving new ones.

Modes of operation * –schema-update: when updating merges two schemas. Works by principle: “what is valid for the old one, is valid for the new one, and vice versa” * –schema-reset: when updating replaces the old schema with the new one.

Disabling update mechanisms * –without-delete: disables deletion of old schemas * –without-update: disables updating of existing schemas * –without-add: disables adding new schemas

(.venv) miskler@MBook:~/pjsss$ pytest --jsss-debug --save-original --schema-update
...........................................                                                                                                                            [100%]
============== Schema Summary ==============
Created schemas (6):
- multi_schema_one.schema.json + original
- multi_schema_two.schema.json + original
- multi_schema_three.schema.json + original
43 passed in 0.32s