[OpenAPI] Add new validation rules / assertions

[tobias-tengler]

No description provided.

[Copilot]

Pull request overview

This PR adds new validation rules for OpenAPI definitions and refactors the error handling model from a result-based pattern to an exception-based pattern. The changes improve type safety by making operation and fragment definitions explicit properties rather than derived values.

Key changes:

• Replaced result-based parsing with exception-based parsing (throws OpenApiDefinitionParsingException on errors)
• Added two new validation rules: EndpointMustHaveOperationNameRule and EndpointHttpMethodMustBeValidRule
• Converted OpenApiEndpointDefinition and OpenApiModelDefinition from records to classes with internal constructors and explicit OperationDefinition/FragmentDefinition properties

Reviewed changes

Copilot reviewed 25 out of 25 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
ValidationTestBase.cs	Updated test to use new generic error message and added test for operation name validation
OpenApiDefinitionParserTests.cs	Updated all parsing tests to expect exceptions instead of checking result objects
OpenApiTestBase.cs	Updated test infrastructure to use OpenApiDefinitionValidationError instead of IOpenApiError and simplified parser usage
OpenApiCollectionArchiveTests.cs	Updated to use new parser signature that returns definitions directly
ModelNoDeferStreamDirectiveRule.cs	Removed definition parameter from validation error constructor
EndpointParameterConflictRule.cs	Removed definition parameter from validation error constructor
EndpointNoDeferStreamDirectiveRule.cs	Removed definition parameter from validation error constructor
EndpointMustHaveValidRouteRule.cs	Removed definition parameter from validation error constructor
EndpointMustHaveSingleRootFieldRule.cs	Removed definition parameter from validation error constructor
EndpointMustHaveNameRule.cs	New validation rule to ensure endpoints have operation names
EndpointMustBeQueryOrMutationRule.cs	Simplified error message and removed definition parameter from validation error constructor
EndpointHttpMethodMustBeValidRule.cs	New validation rule to ensure endpoints have valid HTTP methods
OpenApiDefinitionValidator.cs	Registered two new validation rules in the endpoint validation pipeline
OpenApiDefinitionValidationError.cs	Simplified to only contain message, removed IOpenApiError interface and definition reference
OpenApiDefinitionParsingResult.cs	Removed - no longer needed with exception-based parsing
OpenApiDefinitionParsingException.cs	New exception type for parsing failures
OpenApiDefinitionParsingError.cs	Removed - replaced by exception-based approach
OpenApiDefinitionParser.cs	Refactored to throw exceptions on parse errors, return definitions directly, and include operation/fragment nodes as explicit parameters
IOpenApiError.cs	Removed - no longer needed with simplified error model
OpenApiDiagnosticEventListener.cs	Updated signature to use OpenApiDefinitionValidationError instead of IOpenApiError
IOpenApiDiagnosticEvents.cs	Updated signature to use OpenApiDefinitionValidationError instead of IOpenApiError
AggregateOpenApiDiagnosticEventListener.cs	Updated signature to use OpenApiDefinitionValidationError instead of IOpenApiError
OpenApiModelDefinition.cs	Converted from record to class with internal constructor and explicit FragmentDefinition property
OpenApiEndpointDefinitionParameter.cs	Moved to separate file (previously nested in OpenApiEndpointDefinition.cs)
OpenApiEndpointDefinition.cs	Converted from record to class with internal constructor and explicit OperationDefinition property

---

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[github-actions]

🚀 Fusion Gateway Performance Results

Simple Composite Query

Constant Load (50 VUs)

Requests/sec	Error Rate
5955.22 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
0.77ms	7.02ms	159.91ms	8.25ms	12.63ms	18.30ms

Ramping Load (0→50→500→50 VUs)

Requests/sec	Error Rate
4649.74 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
0.70ms	37.07ms	270.29ms	47.79ms	107.75ms	125.64ms

Executed Query

fragment User on User {
  id
  username
  name
}

fragment Review on Review {
  id
  body
}

fragment Product on Product {
  inStock
  name
  price
  shippingEstimate
  upc
  weight
}

query TestQuery {
  topProducts(first: 5) {
    ...Product
    reviews {
      ...Review
      author {
        ...User
      }
    }
  }
}

Deep Recursion Query

Constant Load (50 VUs)

Requests/sec	Error Rate
268.12 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
12.78ms	175.32ms	736.78ms	181.02ms	228.57ms	255.09ms

Ramping Load (0→50→500→50 VUs)

Requests/sec	Error Rate
309.00 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
3.02ms	683.13ms	1705.20ms	682.20ms	1372.50ms	1494.21ms

Executed Query

fragment User on User {
  id
  username
  name
}

fragment Review on Review {
  id
  body
}

fragment Product on Product {
  inStock
  name
  price
  shippingEstimate
  upc
  weight
}

query TestQuery {
  users {
    ...User
    reviews {
      ...Review
      product {
        ...Product
        reviews {
          ...Review
          author {
            ...User
            reviews {
              ...Review
              product {
                ...Product
              }
            }
          }
        }
      }
    }
  }
  topProducts(first: 5) {
    ...Product
    reviews {
      ...Review
      author {
        ...User
        reviews {
          ...Review
          product {
            ...Product
          }
        }
      }
    }
  }
}

Variable Batching Throughput

Constant Load (50 VUs)

Requests/sec	Error Rate
24045.86 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
0.09ms	1.67ms	53.00ms	2.03ms	3.87ms	4.73ms

Ramping Load (0→50→500→50 VUs)

Requests/sec	Error Rate
18786.99 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
0.09ms	9.23ms	116.28ms	11.23ms	23.13ms	28.01ms

Executed Query

query TestQuery_8f7a46ce_2(
  $__fusion_1_upc: ID!
  $__fusion_2_price: Long!
  $__fusion_2_weight: Long!
) {
  productByUpc(upc: $__fusion_1_upc) {
    inStock
    shippingEstimate(weight: $__fusion_2_weight, price: $__fusion_2_price)
  }
}

Variables (5 sets batched in single request)

[
  { "__fusion_1_upc": "1", "__fusion_2_price": 899, "__fusion_2_weight": 100 },
  { "__fusion_1_upc": "2", "__fusion_2_price": 1299, "__fusion_2_weight": 1000 },
  { "__fusion_1_upc": "3", "__fusion_2_price": 15, "__fusion_2_weight": 20 },
  { "__fusion_1_upc": "4", "__fusion_2_price": 499, "__fusion_2_weight": 100 },
  { "__fusion_1_upc": "5", "__fusion_2_price": 1299, "__fusion_2_weight": 1000 }
]

No baseline data available for comparison.

---

Run 20666439971 • Commit 05da2f8 • Fri, 02 Jan 2026 21:08:25 GMT

[github-actions]

🚀 Fusion Gateway Performance Results

Simple Composite Query

Constant Load (50 VUs)

Requests/sec	Error Rate
5911.02 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
0.77ms	7.04ms	160.45ms	8.31ms	12.73ms	18.34ms

Ramping Load (0→50→500→50 VUs)

Requests/sec	Error Rate
4610.99 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
0.86ms	36.81ms	246.60ms	48.19ms	109.27ms	128.30ms

Executed Query

fragment User on User {
  id
  username
  name
}

fragment Review on Review {
  id
  body
}

fragment Product on Product {
  inStock
  name
  price
  shippingEstimate
  upc
  weight
}

query TestQuery {
  topProducts(first: 5) {
    ...Product
    reviews {
      ...Review
      author {
        ...User
      }
    }
  }
}

Deep Recursion Query

Constant Load (50 VUs)

Requests/sec	Error Rate
270.29 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
12.75ms	172.16ms	624.80ms	179.54ms	224.86ms	260.27ms

Ramping Load (0→50→500→50 VUs)

Requests/sec	Error Rate
306.49 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
3.06ms	663.60ms	1706.81ms	688.18ms	1358.06ms	1464.70ms

Executed Query

fragment User on User {
  id
  username
  name
}

fragment Review on Review {
  id
  body
}

fragment Product on Product {
  inStock
  name
  price
  shippingEstimate
  upc
  weight
}

query TestQuery {
  users {
    ...User
    reviews {
      ...Review
      product {
        ...Product
        reviews {
          ...Review
          author {
            ...User
            reviews {
              ...Review
              product {
                ...Product
              }
            }
          }
        }
      }
    }
  }
  topProducts(first: 5) {
    ...Product
    reviews {
      ...Review
      author {
        ...User
        reviews {
          ...Review
          product {
            ...Product
          }
        }
      }
    }
  }
}

Variable Batching Throughput

Constant Load (50 VUs)

Requests/sec	Error Rate
24177.47 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
0.09ms	1.66ms	45.04ms	2.02ms	3.83ms	4.71ms

Ramping Load (0→50→500→50 VUs)

Requests/sec	Error Rate
19082.62 req/s	0.00%

📊 Response Time Metrics

Min	Med	Max	Avg	P90	P95
0.09ms	8.96ms	99.92ms	11.07ms	23.11ms	27.92ms

Executed Query

query TestQuery_8f7a46ce_2(
  $__fusion_1_upc: ID!
  $__fusion_2_price: Long!
  $__fusion_2_weight: Long!
) {
  productByUpc(upc: $__fusion_1_upc) {
    inStock
    shippingEstimate(weight: $__fusion_2_weight, price: $__fusion_2_price)
  }
}

Variables (5 sets batched in single request)

[
  { "__fusion_1_upc": "1", "__fusion_2_price": 899, "__fusion_2_weight": 100 },
  { "__fusion_1_upc": "2", "__fusion_2_price": 1299, "__fusion_2_weight": 1000 },
  { "__fusion_1_upc": "3", "__fusion_2_price": 15, "__fusion_2_weight": 20 },
  { "__fusion_1_upc": "4", "__fusion_2_price": 499, "__fusion_2_weight": 100 },
  { "__fusion_1_upc": "5", "__fusion_2_price": 1299, "__fusion_2_weight": 1000 }
]

No baseline data available for comparison.

---

Run 20678722814 • Commit b539eec • Sat, 03 Jan 2026 15:00:30 GMT

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (de31cb4) to head (b7249fd).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@     Coverage Diff      @@
##   main   #9030   +/-   ##
============================
============================

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