Connect Pipelines, FME Flow and ArcGIS to NIKA GeoEngine

"""Submit a NIKA GeoEngine job, wait for it, and exit non-zero if it fails.

Usage: GEOENGINE_URL=https://<geoengine-host> GEOENGINE_TOKEN=... \
       python geoengine_job.py payload.json [timeout_seconds]
"""
import json, os, sys, time, urllib.error, urllib.request

BASE = os.environ["GEOENGINE_URL"].rstrip("/")
HEADERS = {"Authorization": "Bearer " + os.environ["GEOENGINE_TOKEN"],
           "Content-Type": "application/json"}


def call(method, path, body=None):
    data = json.dumps(body).encode() if body is not None else None
    req = urllib.request.Request(BASE + path, data=data, method=method, headers=HEADERS)
    with urllib.request.urlopen(req, timeout=30) as resp:
        return json.load(resp)


def run(payload, timeout_seconds=7200):
    job_id = call("POST", "/v1/jobs", payload)["job_id"]
    print("submitted " + job_id, file=sys.stderr)
    deadline, errors = time.time() + timeout_seconds, 0
    while time.time() < deadline:
        try:
            status = call("GET", "/v1/jobs/" + job_id)["status"]
        except urllib.error.HTTPError as exc:
            if exc.code < 500:                # auth or request problem: retrying will not help
                sys.exit("gateway returned HTTP %d for job %s" % (exc.code, job_id))
            status = None                     # 5xx: treat like a network blip
        except OSError:                       # network blip while polling
            status = None
        if status is None:
            errors += 1
            if errors > 5:
                sys.exit("lost contact with the gateway while polling job " + job_id)
        else:
            errors = 0
            if status == "completed":
                return job_id
            if status == "failed":
                sys.exit("job " + job_id + " failed")
        time.sleep(15)
    try:                                      # nobody is waiting any more: stop the job
        call("POST", "/v1/jobs/" + job_id + "/cancel")
    except OSError:
        pass
    sys.exit("job " + job_id + " timed out and was cancelled")


if __name__ == "__main__":
    with open(sys.argv[1]) as f:
        payload = json.load(f)                # worker, version, machine_class, inputs, items
    timeout = int(sys.argv[2]) if len(sys.argv) > 2 else 7200
    print(run(payload, timeout))              # the job ID, for later steps