Call AWS ParallelCluster API with Python

example.py

#!/usr/bin/env python3
import json
from base64 import b64decode, b64encode
from pprint import pprint
import boto3
import botocore
import yaml
import requests

def sigv4_request(method, host, path, params, headers, body):
    "Adds authorization headers for sigv4 to headers parameter."
    endpoint = host.replace("https://", "").replace("http://", "")
    _api_id, _service, region, _domain = endpoint.split(".", maxsplit=3)

    request_parameters = "&".join([f"{k}={v}" for k, v in params.items()])
    url = f"{host}{path}?{request_parameters}"

    session = botocore.session.Session()
    body_data = json.dumps(body) if body else None
    request = botocore.awsrequest.AWSRequest(method=method, url=url, data=body_data)
    botocore.auth.SigV4Auth(session.get_credentials(), "execute-api", region).add_auth(request)
    boto_request = request.prepare()

    req_call = {
        "POST": requests.post,
        "GET": requests.get,
        "PUT": requests.put,
        "PATCH": requests.patch,
        "DELETE": requests.delete,
    }.get(method)

    for k, val in headers.items():
        boto_request.headers[k] = val

    return req_call(boto_request.url, data=body_data, headers=boto_request.headers, timeout=30)

def create(region, baseurl, cluster_name, config_file):
    # parse config file
    path = "/v3/clusters"

    config_data = b64decode(config_file).decode("ascii")

    params = {"region": region}
    body = {"clusterConfiguration": config_data, "clusterName": cluster_name}
    headers = {"content-type": "application/json"}
    resp = sigv4_request("POST", baseurl, path, params, headers, body)
    pprint(resp.json())


def list_clusters(region, baseurl):
    path = "/v3/clusters"
    params = {"region": region}
    resp = sigv4_request("GET", baseurl, path, params, {}, None)
    pprint(resp.json())


if __name__ == "__main__":
    config = """
    Image:
      Os: ubuntu2004
    #  CustomAmi: ami-0016baecd80fb8f18
    HeadNode:
      InstanceType: t2.large
      Networking:
        SubnetId: subnet-01ff8b514162d9a92
      Ssh:
        KeyName: enguard
    Scheduling:
      Scheduler: slurm
      SlurmQueues:
      - Name: queue0
        ComputeResources:
        - Name: queue0-i0
          InstanceType: t2.micro
          MinCount: 1
          MaxCount: 11
        Networking:
          SubnetIds:
          - subnet-08190f2e7fe1f140e
    """
    baseurl = "https://mdxwg8m984.execute-api.us-east-2.amazonaws.com/prod"
    cluster_name = "XXX"
    list_clusters("us-east-2", baseurl)
    create("us-east-2", baseurl, cluster_name, b64encode(config.encode("ascii")))

You'll need boto3, yaml, requests

Step 1

First Deploy the AWS ParallelCluster API

Region	Launch
North Virginia (us-east-1)
Oregon (us-west-2)
Ireland (eu-west-1)
Frankfurt (eu-central-1)

Step 2

Look at the stack outputs and grab ParallelClusterApiInvokeUrl , paste that into the baseurl parameter in the example python script.

Also add a Cluster Name, Region and update SubnetID to your subnet.