covalent-awslambda-plugin 0.8.3rc0

Covalent AWS Lambda Executor Plugin

 

Covalent AWS Lambda Plugin

Covalent is a Pythonic workflow tool used to execute tasks on advanced computing hardware. This executor plugin interfaces Covalent with AWS Lambda for dispatching compute.

To use this plugin with Covalent, install it with pip:

pip install covalent-awslambda-plugin

In order for workflows to leverage this executor, users must ensure that all the necessary IAM permissions are properly setup and configured. This executor uses the S3 and AWS Lambda service to execute an electron, thus the IAM roles/policies must be configured correctly. Precisely, the following IAM permissions are needed for the executor to run any dispatched electrons properly

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:*",
                "s3-object-lambda:*"
            ],
            "Resource": [
                "arn:aws:s3:::<bucket-name>",
                "arn:aws:s3:::<bucket-name>/*"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "cloudformation:DescribeStacks",
                "cloudformation:ListStackResources",
                "cloudwatch:ListMetrics",
                "cloudwatch:GetMetricData",
                "ec2:DescribeSecurityGroups",
                "ec2:DescribeSubnets",
                "ec2:DescribeVpcs",
                "kms:ListAliases",
                "iam:GetPolicy",
                "iam:GetPolicyVersion",
                "iam:GetRole",
                "iam:GetRolePolicy",
                "iam:ListAttachedRolePolicies",
                "iam:ListRolePolicies",
                "iam:ListRoles",
                "lambda:*",
                "logs:DescribeLogGroups",
                "states:DescribeStateMachine",
                "states:ListStateMachines",
                "tag:GetResources",
                "xray:GetTraceSummaries",
                "xray:BatchGetTraces"
            ],
            "Resource": "*"
        },
        {
            "Effect": "Allow",
            "Action": "iam:PassRole",
            "Resource": "*",
            "Condition": {
                "StringEquals": {
                    "iam:PassedToService": "lambda.amazonaws.com"
                }
            }
        },
        {
            "Effect": "Allow",
            "Action": [
                "logs:DescribeLogStreams",
                "logs:GetLogEvents",
                "logs:FilterLogEvents"
            ],
            "Resource": "arn:aws:logs:*:*:log-group:/aws/lambda/*"
        }
    ]
}

where <bucket-name> is the name of the S3 bucket configured to the Lambda executor to upload and download objects from. The default bucket name is set to covalent-lambda-job-resources and it must be present prior to running the executor. The S3 bucket can either be created using the awscli or with the AWS web console. To create a S3 bucket using the AWS CLI, the following can be used

pip install awscli
aws configure
aws s3api create-bucket --bucket `my-s3-bucket-for-covalent` --region `us-east-1`

Secondly, the lambda function created by this executor on AWS also needs an IAM role with suitable permisisons to execute. By default, this executor assumes there exists a IAM role CovalentLambdaExecutionRole with the AWSLambdaExecute execute policy attached to it. The policy document is summarized here for convenience

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "logs:*"
            ],
            "Resource": "arn:aws:logs:*:*:*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "s3:GetObject",
                "s3:PutObject"
            ],
            "Resource": "arn:aws:s3:::*"
        }
    ]
}

Users can optionally configure this executor by specifying its properties in their Covalent configuration file. Following is a section showing the default configuration values for this executor

[executors.awslambda]
credentials = "/home/user/.aws/credentials"
profile = "default"
region = "us-east-1"
lambda_role_name = "CovalentLambdaExecutionRole"
s3_bucket_name = "covalent-lambda-job-resources"
cache_dir = "/home/user/.cache/covalent"
poll_freq = 5
timeout = 60
memory_size = 512
cleanup = true

To this executor in their workflows, users can either create an instance of the AWSLambdaExecutor class with their custom configuration values or simply use the defaults. The following code snippets illustrate how this can be done in a workflow

# Custom configuration
from covalent.executor import AWSLambdaExecutor
lambda_executor = AWSLambdaExecutor(credentials="my_custom_credentials",
                    profile="custom_profile",
                    region="us-east-1",
                    lambda_role_name="custom_role_name",
                    s3_bucket_name="custom_s3_bucket_name",
                    cache_dir="custom_cache_dir_location",
                    poll_freq="custom_integer_value",
                    timeout="custom_timeout_value (max 900s)",
                    memory_size="custom_memory_size (max 512 M)",
                    cleanup="True or False")

@ct.electron(executor=lambda_executor)
def my_task(...):
    ...

If the values specified in the configuration file are to be used, the executor can be used as follows

@ct.electron(executor="awslambda"):
def my_task(...):
    ...

Release Notes

Release notes are available in the Changelog.

Citation

Please use the following citation in any publications:

W. J. Cunningham, S. K. Radha, F. Hasan, J. Kanem, S. W. Neagle, and S. Sanand. Covalent. Zenodo, 2022. https://doi.org/10.5281/zenodo.5903364

License

Covalent is licensed under the GNU Affero GPL 3.0 License. Covalent may be distributed under other licenses upon request. See the LICENSE file or contact the support team for more details.