GripMock

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YAML Stubs ​

YAML stubs describe the same structure as JSON stubs, plus comments, anchors and multi-document files. See Why YAML? for the comparison.

Schema Validation ​

GripMock provides a JSON Schema for validating stub definitions. Add this to your YAML files for IDE support:

yaml
# yaml-language-server: $schema=https://bavix.github.io/gripmock/schema/stub.json

service: MyService
method: MyMethod
output:
  data:
    result: success

When to Use YAML ​

Stub files load from disk at startup, so a test suite runs without touching the HTTP API, the stub set is versioned alongside the code, and it scales to large numbers of stubs.

Project Structure ​

project-root/  
├── proto/  
│   └── simple.proto    # gRPC contract  
└── stubs/  
    ├── single.yaml     # Single stub  
    ├── multi-stubs.yml # Multiple stubs  
    └── nested/         # Organize in subdirectories

Stub Syntax ​

Single Stub (single.yaml) ​

yaml
service: Gripmock  
method: SayHello  
input:  
  equals:  
    name: yaml-single  
output:  
  data:  
    message: Hello YAML  
    returnCode: 1

Multiple Stubs (multi-stubs.yml) ​

yaml
- service: Gripmock  
  method: SayHello  
  priority: 100
  input:  
    equals:  
      name: alpha  
  output:  
    data:  
      message: Hello Alpha  
      returnCode: 1  

- service: Gripmock  
  method: SayHello  
  priority: 1
  input:  
    equals:  
      name: beta  
  output:  
    data:  
      message: Hello Beta  
      returnCode: 2

Docker Execution ​

bash
docker run \  
  -p 4770:4770 \  
  -p 4771:4771 \  
  -v $(pwd)/proto:/proto:ro \  
  -v $(pwd)/stubs:/stubs:ro \  
  bavix/gripmock \  
  --stub=/stubs \  
  /proto/simple.proto

Verification ​

Check loaded stubs:

bash
curl http://localhost:4771/api/stubs

Sample Response:

json
[
  {
    "id": "550e8400-e29b-41d4-a716-446655440000",
    "service": "Gripmock",
    "method": "SayHello",
    "input": { "equals": { "name": "yaml-single" } },
    "output": { "data": { "message": "Hello YAML" } }
  },
  ...
]

Advanced Features ​

Array Order Handling ​

yaml
input:  
  ignoreArrayOrder: true  
  equals:  
    ids: [3, 1, 2]

Nested Structures ​

yaml
input:  
  contains:  
    metadata:  
      env: production  
      version: 2.1

Key notes ​

  • Auto-reloading: the stub watcher is on by default and picks up file changes without a restart. See Why IDs matter.
  • Recursive loading: every .yaml / .yml file under --stub is read.
  • Validation: a syntax error in a stub file prevents server startup.
  • File stubs and the HTTP API coexist; a hybrid setup is fine.
  • priority controls which stub wins when several match.

For schema details, see JSON Schema for stubs.