Description:

When executing sam local start-api command with an APIGateway and a Lambda Proxy Integration SAM injects a payload where the requestTimeEpoch context variable is injected as epoch seconds. However, according to the AWS documentation This value should be passed in with millisecond resolution

Steps to reproduce:

1. Create a cloudformation template with an ApiGatewa + Lambda Proxy integration which logs the event.
2. Start the API with sam local start-api
3. Take a look at the logged event

Observed result:

The event contains requestTimeEpoch with unit seconds
Example event payload:

{
  // ... other properties
  "requestContext": {
    // ... other properties
    "requestTime": "13/May/2025:18:26:58 +0000",
    "requestTimeEpoch": 1747160818 
  }
}

Expected result:

The event contains requestTimeEpoch with unit milliseconds
Example event payload:

{
  // ... other properties
  "requestContext": {
    // ... other properties
    "requestTime": "13/May/2025:18:26:58 +0000",
    "requestTimeEpoch": 1747160818000 
  }
}

Additional environment details (Ex: Windows, Mac, Amazon Linux etc)

1. OS: macOS-15.4.1-arm64-arm-64bit-Mach-O
2. sam --version: SAM CLI, version 1.138.0
3. AWS region: us-east-1

{
  "version": "1.138.0",
  "system": {
    "python": "3.13.3",
    "os": "macOS-15.4.1-arm64-arm-64bit-Mach-O"
  },
  "additional_dependencies": {
    "docker_engine": "28.1.1",
    "aws_cdk": "Not available",
    "terraform": "Not available"
  },
  "available_beta_feature_env_vars": [
    "SAM_CLI_BETA_FEATURES",
    "SAM_CLI_BETA_BUILD_PERFORMANCE",
    "SAM_CLI_BETA_TERRAFORM_SUPPORT",
    "SAM_CLI_BETA_PACKAGE_PERFORMANCE",
    "SAM_CLI_BETA_RUST_CARGO_LAMBDA"
  ]
}

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