feat: allow to pass a custom JSONDecoder to OnRequestHandler

[DominikPalo]

This PR allows providing a custom instance of JSONEncoder while initializing the OnRequestHandler.

Motivation

Some API endpoints require all JSON keys in payloads to adhere to the snake-case naming convention. However, to be consistent with the Swift naming convention, we use camelCase naming convention for declaring properties in underlying Codable structures (JSON models). When calling the API, we configure the Alamofire key encoding strategy to snake-case (encoder.keyEncodingStrategy = .convertToSnakeCase). Unfortunately, with the current implementation, it is not possible to mock such endpoints, as the request handler always uses the default JSONDecoder() for parsing/decoding the request body.

After applying this PR, it will be possible to configure the JSONDecoder as needed; for example, in our case, to set the key decoding strategy to snake_case:

let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase

mock.onRequestHandler = OnRequestHandler(httpBodyType: BodyType.self, jsonDecoder: decoder) { _, body in
	// Assertions
}

[raphkoebraam]

Thank you for the contribution and for validating it with tests, @DominikPalo! 🚀

[wetransferplatform]

	Warnings
⚠️	'onRequest' is deprecated: Use onRequestHandler instead.
⚠️	'onRequest' is deprecated: Use onRequestHandler instead.

	Messages
📖	MockerTests: Executed 33 tests (0 failed, 0 retried, 0 skipped) in 1.841 seconds
📖	View more details on Bitrise

Code Coverage Report

Name	Coverage
Mocker	82.35%	✅

SwiftLint found issues

Severity	File	Reason
Warning	OnRequestHandler.swift:30	Line should be 140 characters or less; currently it has 149 characters (line_length)
Warning	OnRequestHandler.swift:56	Line should be 140 characters or less; currently it has 149 characters (line_length)
Error	OnRequestHandler.swift:66	Line should be 160 characters or less; currently it has 168 characters (line_length)
Error	OnRequestHandler.swift:82	Line should be 160 characters or less; currently it has 163 characters (line_length)
Warning	MockerTests.swift:374	Prefer named constructors over .init and type inference (explicit_init)
Warning	MockerTests.swift:400	Prefer named constructors over .init and type inference (explicit_init)
Warning	MockerTests.swift:422	Prefer named constructors over .init and type inference (explicit_init)
Warning	MockerTests.swift:441	Prefer named constructors over .init and type inference (explicit_init)
Warning	MockerTests.swift:666	File should contain 660 lines or less: currently contains 666 (file_length)
Warning	MockerTests.swift:187	Line should be 140 characters or less; currently it has 151 characters (line_length)
Warning	MockerTests.swift:205	Line should be 140 characters or less; currently it has 149 characters (line_length)
Warning	MockerTests.swift:263	Line should be 140 characters or less; currently it has 157 characters (line_length)
Warning	MockerTests.swift:400	Line should be 140 characters or less; currently it has 145 characters (line_length)
Warning	MockerTests.swift:52	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:71	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:94	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:116	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:148	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:173	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:189	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:207	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:230	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:283	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:574	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:608	Chained function calls should be either on the same line, or one per line (multiline_function_chains)
Warning	MockerTests.swift:261	Variables should not have redundant type annotation (redundant_type_annotation)
Warning	MockerTests.swift:132	Use shorthand syntax for optional binding (shorthand_optional_binding)
Warning	MockerTests.swift:267	Use shorthand syntax for optional binding (shorthand_optional_binding)
Warning	MockerTests.swift:562	Use shorthand syntax for optional binding (shorthand_optional_binding)
Warning	MockerTests.swift:152	Lines should not have trailing whitespace (trailing_whitespace)
Warning	MockerTests.swift:167	Lines should not have trailing whitespace (trailing_whitespace)
Warning	MockerTests.swift:15	Type body should span 400 lines or less excluding comments and whitespace: currently spans 465 lines (type_body_length)
Warning	MockerTests.swift:48	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:67	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:90	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:112	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:130	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:162	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:185	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:203	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:226	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:242	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:265	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:557	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:600	Parentheses are not needed when declaring closure arguments (unneeded_parentheses_in_closure_argument)
Warning	MockerTests.swift:316	Prefer the specific matcher 'XCTAssertEqual' instead (xct_specific_matcher)

Generated by 🚫 Danger Swift against 47cdf02

[BasThomas]

👌 nice!