Lambda Function ARN — Serverless Function References
Parse an AWS Lambda function ARN to understand version qualifiers, alias ARNs, and the colon-separated resource format used by Lambda.
Detailed Explanation
Lambda Function ARN Variants
Lambda function ARNs use a colon-separated resource format and support multiple qualifiers for versions and aliases.
Basic Function ARN
arn:aws:lambda:us-east-1:123456789012:function:my-api-handler
Parsed Components
| Component | Value |
|---|---|
| Partition | aws |
| Service | lambda |
| Region | us-east-1 |
| Account ID | 123456789012 |
| Resource Type | function |
| Resource ID | my-api-handler |
Version and Alias Qualifiers
Lambda ARNs can include a version number or alias name after the function name:
- Specific version:
arn:aws:lambda:us-east-1:123456789012:function:my-api-handler:42 - Named alias:
arn:aws:lambda:us-east-1:123456789012:function:my-api-handler:production - Latest (unqualified):
arn:aws:lambda:us-east-1:123456789012:function:my-api-handler
The unqualified ARN always points to the $LATEST version. Using version numbers or aliases in ARNs is critical for production deployments because it lets you pin to a known-good version.
Colon vs. Slash Resource Format
Lambda uses colons to separate the resource type (function) from the function name, unlike IAM which uses slashes. This is why arn:...:function:my-handler has an extra colon segment. The ARN parser handles both conventions transparently.
Event Source Mappings
Lambda also has ARNs for event source mappings and layers:
- Layer:
arn:aws:lambda:us-east-1:123456789012:layer:my-layer:3 - Event source mapping:
arn:aws:lambda:us-east-1:123456789012:event-source-mapping:uuid
Use Case
Configuring API Gateway integrations, SNS subscriptions, or EventBridge rules that invoke Lambda functions. The function ARN (with or without a version/alias qualifier) is required in the target configuration.