AWS Lambda#

Lithops with AWS Lambda as serverless compute backend.

Configuration#

  1. Login to Amazon Web Services Console (or signup if you don’t have an account)

  2. Navigate to IAM > Policies. Click on Create policy.

  3. Select JSON tab and paste the following JSON policy:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:*",
                "lambda:*",
                "ec2:*",
                "ecr:*",
                "sts:GetCallerIdentity",
                "logs:CreateLogGroup",
                "logs:CreateLogStream",
                "logs:PutLogEvents"
            ],
            "Resource": "*"
        }
    ]
}
  1. Click Next: Tags and Next: Review. Fill the policy name field (you can name it lithops-policy or simmilar) and create the policy.

  2. Go back to IAM and navigate to Roles tab. Click Create role.

  3. Choose Lambda on the use case list and click Next: Permissions. Select the policy created before (lithops-policy). Click Next: Tags and Next: Review. Type a role name, for example lithops-execution-role. Click on Create Role.

AWS Credential setup#

Lithops loads AWS credentials as specified in the boto3 configuration guide.

In summary, you can use one of the following settings:

  1. Provide the credentials via the ~/.aws/config file, or set the AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables.

    You can run aws configure command if the AWS CLI is installed to setup the credentials. Then set in the Lithops config file:

    lithops:
        backend: aws_lambda
    
    aws_lambda:
        execution_role: <EXECUTION_ROLE_ARN>
        region: <REGION_NAME>
    
  2. Provide the credentials in the aws section of the Lithops config file:

    lithops:
        backend: aws_lambda
    
    aws:
        access_key_id: <AWS_ACCESS_KEY_ID>
        secret_access_key: <AWS_SECRET_ACCESS_KEY>
        region: <REGION_NAME>
    
    aws_lambda:
        execution_role: <EXECUTION_ROLE_ARN>
    

Summary of configuration keys for AWS#

AWS#

Group

Key

Default

Mandatory

Additional info

aws

region

yes

AWS Region. For example us-east-1

aws

access_key_id

no

Account access key to AWS services. To find them, navigate to My Security Credentials and click Create Access Key if you don’t already have one.

aws

secret_access_key

no

Account secret access key to AWS services. To find them, navigate to My Security Credentials and click Create Access Key if you don’t already have one.

aws

session_token

no

Session token for temporary AWS credentials

aws

account_id

no

*This field will be used if present to retrieve the account ID instead of using AWS STS. The account ID is used to format full image names for container runtimes.

AWS Lambda#

Group

Key

Default

Mandatory

Additional info

aws_lambda

execution_role

yes

ARN of the execution role created at step 3. You can find it in the Role page at the Roles list in the IAM section (e.g. arn:aws:iam::1234567890:role/lithops-execution-role

aws_lambda

region

no

Region where Lambda functions will be invoked (e.g. us-east-1). Lithops will use the region set under the aws section if it is not set here

aws_lambda

max_workers

1000

no

Max number of workers per FunctionExecutor()

aws_lambda

worker_processes

1

no

Number of Lithops processes within a given worker. This can be used to parallelize function activations within a worker

aws_lambda

runtime

no

Docker image name

aws_lambda

runtime_memory

256

no

Memory limit in MB. Default 256MB

aws_lambda

runtime_timeout

180

no

Runtime timeout in seconds. Default 3 minutes

aws_lambda

invoke_pool_threads

64

no

Number of concurrent threads used for invocation

aws_lambda

remote_invoker

False

no

Activate the remote invoker feature that uses one cloud function to spawn all the actual map() activations

aws_lambda

architecture

x86_64

no

Runtime architecture. One of x86_64 or arm64

aws_lambda

ephemeral_storage

512

no

Ephemeral storage (/tmp) size in MB (must be between 512 MB and 10240 MB)

aws_lambda

env_vars

{}

no

List of {name: …, value: …} pairs for Lambda instance environment variables

aws_lambda

namespace

no

Virtual namespace. This can be usefull to virtually group Lithops function workers. The functions deployed by lithops will be prefixed by this namespace. For example you can set it to differentiate between prod, dev and stage environments.

aws_lambda

runtime_include_function

False

no

If set to true, Lithops will automatically build a new runtime, including the function’s code, instead of transferring it through the storage backend at invocation time. This is useful when the function’s code size is large (in the order of 10s of MB) and the code does not change frequently

Additional configuration#

VPC#

To connect the Lithops lambda to a VPC, add the following configuration to the aws_lambda configuration section:

aws_lambda:
    execution_role: <EXECUTION_ROLE_ARN>
    region: <REGION_NAME>
    vpc:
        subnets:
            - <SUBNET_ID_1>
            - <SUBNET_ID_2>
            ...
        security_groups:
            - <SECURITY_GROUP_1>
            - <SECURITY_GROUP_2>
                ...
  • subnets: A list of VPC subnet IDs.

  • security_groups: A list of VPC security groups IDs.

Note: To be able to create network interfaces for Lambda functions, the role created in step 3 has to have permissions to do so, for example by adding the permission EC2FullAccess.

For more information, check out AWS documentation on VPCs.

EFS#

To attach EFS volumes to the Lithops lambda, add the following configuration to the aws_lambda configuration section:

aws_lambda:
    execution_role: <EXECUTION_ROLE_ARN>
    region: <REGION_NAME>
    vpc:
        ...
    efs:
        - access_point: <EFS_ACCESS_POINT_1>
          mount_path: <LAMBDA_VOLUME_MOUNT_PATH_1>
        - access_point: <EFS_ACCESS_POINT_2>
          mount_path: <LAMBDA_VOLUME_MOUNT_PATH_2>
            ...
  • access_point: The Amazon Resource Name (ARN) of the Amazon EFS access point that provides access to the file system.

  • mount_path: The path where the function can access the file system. It must start with /mnt.

Note: to access those volumes, the Lithops lambda has to be connected to the same VPC and subnets as the EFS volumes are mounted to.

For more information, check out AWS documentation on attaching EFS volumes to Lambda.

Test Lithops#

Once you have your compute and storage backends configured, you can run a hello world function with:

lithops hello -b aws_lambda -s aws_s3

Viewing the execution logs#

You can view the function executions logs in your local machine using the lithops client:

lithops logs poll