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How do I test my PEM key?

Craig Conover

How do I test my APN push notification certificates (PEM key)?

You can test your PEM key using the following command, which should hang if successful until you press enter:

openssl s_client -connect gateway.sandbox.push.apple.com:2195 -cert pnpush.pem -key pnpush.pem

The above tests the PEM Key in sandbox mode. For production mode, use the following command:

openssl s_client -connect gateway.push.apple.com:2195 -cert pnpush.pem -key pnpush.pem

You can also test your PEM Key by running the Python script below using the script below. The usage would be:

python push_debug.py <CERT_PATH> <DEVICE_TOKEN>

This will send test notifications completely outside of PubNub just to sanity check that the cert+apple's registration is configured properly.

debug_push.py

import json
import logging
import os
import socket
import ssl
import struct
import sys
import time
import uuid
import argparse

APNS_HOST = 'gateway.push.apple.com'
APNS_HOST_SANDBOX = 'gateway.sandbox.push.apple.com'
APNS_PORT = 2195

APNS_ERRORS = {
    1:'Processing error',
    2:'Missing device token',
    3:'missing topic',
    4:'missing payload',
    5:'invalid token size',
    6:'invalid topic size',
    7:'invalid payload size',
    8:'invalid token',
    255:'Unknown'
}

def push(cert_path, device, sandbox):
    if not os.path.exists(cert_path):
        logging.error("Invalid certificate path: %s" % cert_path)
        sys.exit(1)

    device = device.decode('hex')
    expiry = time.time() + 3600

    try:
        sock = ssl.wrap_socket(
            socket.socket(socket.AF_INET, socket.SOCK_STREAM),
            certfile=cert_path
        )
        host = APNS_HOST_SANDBOX if sandbox else APNS_HOST
        sock.connect((host, APNS_PORT))
        sock.settimeout(1)
    except Exception as e:
        logging.error("Failed to connect: %s" % e)
        sys.exit(1)

    logging.info("Connected to APNS\n")

    for ident in range(1,4):
        logging.info("Sending %d of 3 push notifications" % ident)

        payload = json.dumps({
            'aps': {
                'alert': 'Push Test %d: %s' % (ident, str(uuid.uuid4())[:8])
            }
        })

        items = [1, ident, expiry, 32, device, len(payload), payload]

        try:
            sent = sock.write(struct.pack('!BIIH32sH%ds'%len(payload), *items))
            if sent:
                logging.info("Message sent\n")
            else:
                logging.error("Unable to send message\n")
        except socket.error as e:
            logging.error("Socket write error: %s", e)

        # If there was an error sending, we will get a response on socket
        try:
            response = sock.read(6)
            command, status, failed_ident = struct.unpack('!BBI',response[:6])
            logging.info("APNS Error: %s\n", APNS_ERRORS.get(status))
            sys.exit(1)
        except socket.timeout:
            pass
        except ssl.SSLError:
            pass

    sock.close()

if __name__ == '__main__':
    parser = argparse.ArgumentParser(description="Send test APNS notifications to device using cert")
    parser.add_argument("certificate", help="Push certificate")
    parser.add_argument("device_id", help="Device ID")
    parser.add_argument("-s", "--sandbox", action="store_true", help="Use APNS sandbox environment")
    args = parser.parse_args()

    logging.basicConfig(level=logging.INFO)
    push(args.certificate, args.device_id, args.sandbox)
    logging.info("Complete\n")

Usage

push_debug.py [-h] [-s] certificate device_id

Send test APNS notifications to device using cert

positional arguments:

  • certificate: Push certificate
  • device_id: Device ID

optional arguments:

  • -h, --help show this help message and exit
  • -s, --sandbox Use APNS sandbox environment

The push certificate file is the same file that would be uploaded to PubNub. Read the iOS docs for more instructions.

Examples

Send notification through production environment

python push_debug.py my_certificate.pem c35124fd2676d646423705b0721004e3b8426d163e10dbf76b46347a4477f12b

Send notification through sandbox environment

python push_debug.py -s my_certificate.pem 3f3980225497e1846fb5c2db9e0b3510023402c7a772011106c702d2aec20cc5

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