def get_dcv_session()

in api/PclusterApiHandler.py [0:0]

• 41 lines of code
• 8 McCabe index (conditional complexity)

def get_dcv_session():
    start = time.time()
    user = request.args.get("user", "ec2-user")
    instance_id = request.args.get("instance_id")
    dcv_command = "/opt/parallelcluster/scripts/pcluster_dcv_connect.sh"
    session_directory = f"/home/{user}"

    if request.args.get("region"):
        config = botocore.config.Config(region_name=request.args.get("region"))
        ssm = boto3.client("ssm", config=config)
    else:
        ssm = boto3.client("ssm")

    command = f"runuser -l {user} -c '{dcv_command} {session_directory}'"

    ssm_resp = ssm.send_command(
        InstanceIds=[instance_id],
        DocumentName="AWS-RunShellScript",
        Comment="Create DCV Session",
        Parameters={"commands": [command]},
    )

    command_id = ssm_resp["Command"]["CommandId"]

    # Wait for command to complete
    time.sleep(0.75)
    while time.time() - start < 15:
        status = ssm.get_command_invocation(CommandId=command_id, InstanceId=instance_id)
        if status["Status"] != "InProgress":
            break
        time.sleep(0.75)

    if time.time() - start > 15:
        raise Exception("Timed out waiting for dcv session to start.")

    if status["Status"] != "Success":
        raise Exception(status["StandardErrorContent"])

    output = status["StandardOutputContent"]

    dcv_parameters = re.search(
        r"PclusterDcvServerPort=([\d]+) PclusterDcvSessionId=([\w]+) PclusterDcvSessionToken=([\w-]+)", output
    )

    if not dcv_parameters:
        raise Exception("Something went wrong during DCV connection. Check logs in /var/log/parallelcluster/ .")

    ret = {
        "port": dcv_parameters.group(1),
        "session_id": dcv_parameters.group(2),
        "session_token": dcv_parameters.group(3),
    }
    return ret