push-notify-apn

push-notify-apn is a library and command line utility that can be used to send push notifications to mobile devices running iOS. Push notifications are small messages that can be sent to apps on smart phones and tablets without the need to keep open a long lived TCP connection per app, dramatically reducing the power consumption in standby mode.

The library is still in an experimental state but apparently is used by a few people and seems to be working. Bug and success reports as well as feature and pull requests are very welcome!

Sending a message is as simple as:

let sandbox     = True  -- Development environment
    maxParallel = 10    -- Number of parallel connections to
                        -- the APN Servers
    useJwt      = False -- No message bearer Token
session <- newSession (Just "my.key") (Just "my.crt")
    (Just "/etc/ssl/ca_certificates.txt") useJwt sandbox
    maxParallel "my.bundle.id"
let payload = alertMessage "Title" "Hello From Haskell"
    message = newMessage payload
    token   = base16EncodedToken "the-token"
success <- sendMessage session token None payload
print success

command line utility

The command line utility can be used for testing your app. Use like this:

sendapn -c ../apn.crt -k ../apn.key -a \
    /etc/ssl/certs/ca-certificates.crt -b your.bundle.id -s \
    -t your-token -m "Your-message"

The -s flag means "sandbox", i.e., for apps that are deployed in a development environment.

You can also use an interactive mode, where messages are read from stdin in this format:

token:sound:title:message

To use, invoke like this:

stack exec -- sendapn -k ~/your.key -c ~/your.crt -a /etc/ssl/cert.pem -b your.application.identifier -s -i

Do remove the -s flag when using the production instead of the sandbox environment.

credentials

your.crt and your.key are the certificate and private key of your APN certificate from apple. To extract them from a .p12 file, you can use openssl:

openssl pkcs12 -in mycredentials.p12 -out your.crt -nokeys
openssl pkcs12 -in mycredentials.p12 -nodes -out your.key -nocerts

/etc/ssl/cert.pem is a truststore that contains the CA certificates that are used to verify the apn server's server certificates. You can create your own truststore that contains only the CAs you are sure are authorized to sign the push notification servers' certificates.