github.com/Jeffail/benthos/v3@v3.65.0/website/docs/components/processors/aws_lambda.md

---
title: aws_lambda
type: processor
status: stable
categories: ["Integration"]
---

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     THIS FILE IS AUTOGENERATED!

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     lib/processor/aws_lambda.go
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import Tabs from '@theme/Tabs';
import TabItem from '@theme/TabItem';


Invokes an AWS lambda for each message. The contents of the message is the
payload of the request, and the result of the invocation will become the new
contents of the message.

Introduced in version 3.36.0.


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  { label: 'Advanced', value: 'advanced', },
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<TabItem value="common">

```yaml
# Common config fields, showing default values
label: ""
aws_lambda:
  parallel: false
  function: ""
  region: eu-west-1
```

</TabItem>
<TabItem value="advanced">

```yaml
# All config fields, showing default values
label: ""
aws_lambda:
  parallel: false
  function: ""
  rate_limit: ""
  region: eu-west-1
  endpoint: ""
  credentials:
    profile: ""
    id: ""
    secret: ""
    token: ""
    role: ""
    role_external_id: ""
  timeout: 5s
  retries: 3
```

</TabItem>
</Tabs>

It is possible to perform requests per message of a batch in parallel by setting
the `parallel` flag to `true`. The `rate_limit`
field can be used to specify a rate limit [resource](/docs/components/rate_limits/about)
to cap the rate of requests across parallel components service wide.

In order to map or encode the payload to a specific request body, and map the
response back into the original payload instead of replacing it entirely, you
can use the [`branch` processor](/docs/components/processors/branch).

### Error Handling

When Benthos is unable to connect to the AWS endpoint or is otherwise unable to invoke the target lambda function it will retry the request according to the configured number of retries. Once these attempts have been exhausted the failed message will continue through the pipeline with it's contents unchanged, but flagged as having failed, allowing you to use [standard processor error handling patterns](/docs/configuration/error_handling).

However, if the invocation of the function is successful but the function itself throws an error, then the message will have it's contents updated with a JSON payload describing the reason for the failure, and a metadata field `lambda_function_error` will be added to the message allowing you to detect and handle function errors with a [`branch`](/docs/components/processors/branch):

```yaml
pipeline:
  processors:
    - branch:
        processors:
          - aws_lambda:
              function: foo
        result_map: |
          root = if meta().exists("lambda_function_error") {
            throw("Invocation failed due to %v: %v".format(this.errorType, this.errorMessage))
          } else {
            this
          }
output:
  switch:
    retry_until_success: false
    cases:
      - check: errored()
        output:
          reject: ${! error() }
      - output:
          resource: somewhere_else
```

### Credentials

By default Benthos will use a shared credentials file when connecting to AWS
services. It's also possible to set them explicitly at the component level,
allowing you to transfer data across accounts. You can find out more
[in this document](/docs/guides/cloud/aws).

## Examples

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{ label: 'Branched Invoke', value: 'Branched Invoke', },
]}>

<TabItem value="Branched Invoke">


This example uses a [`branch` processor](/docs/components/processors/branch/) to map a new payload for triggering a lambda function with an ID and username from the original message, and the result of the lambda is discarded, meaning the original message is unchanged.

```yaml
pipeline:
  processors:
    - branch:
        request_map: '{"id":this.doc.id,"username":this.user.name}'
        processors:
          - aws_lambda:
              function: trigger_user_update
```

</TabItem>
</Tabs>

## Fields

### `parallel`

Whether messages of a batch should be dispatched in parallel.


Type: `bool`  
Default: `false`  

### `function`

The function to invoke.


Type: `string`  
Default: `""`  

### `rate_limit`

An optional [`rate_limit`](/docs/components/rate_limits/about) to throttle invocations by.


Type: `string`  
Default: `""`  

### `region`

The AWS region to target.


Type: `string`  
Default: `"eu-west-1"`  

### `endpoint`

Allows you to specify a custom endpoint for the AWS API.


Type: `string`  
Default: `""`  

### `credentials`

Optional manual configuration of AWS credentials to use. More information can be found [in this document](/docs/guides/cloud/aws).


Type: `object`  

### `credentials.profile`

A profile from `~/.aws/credentials` to use.


Type: `string`  
Default: `""`  

### `credentials.id`

The ID of credentials to use.


Type: `string`  
Default: `""`  

### `credentials.secret`

The secret for the credentials being used.


Type: `string`  
Default: `""`  

### `credentials.token`

The token for the credentials being used, required when using short term credentials.


Type: `string`  
Default: `""`  

### `credentials.role`

A role ARN to assume.


Type: `string`  
Default: `""`  

### `credentials.role_external_id`

An external ID to provide when assuming a role.


Type: `string`  
Default: `""`  

### `timeout`

The maximum period of time to wait before abandoning an invocation.


Type: `string`  
Default: `"5s"`  

### `retries`

The maximum number of retry attempts for each message.


Type: `int`  
Default: `3`