strophe

XMPP support based on libstrophe.

miyako/4d-plugin-strophe

About

This plugin is a minimal proof of concept client for sending and receiving messages via XMPP. It covers only a fraction of what is actually possible with libstrophe.

XMPP enables the near-real-time exchange of structured yet extensible data between any two or more network entities.

near-real-time exchange: libstrophe can be used to install event handlers (xmpp_handler_add, xmpp_id_handler_add, xmpp_timed_handler_add), which are callback functions fired when a specific stanza arrives or periodically. For simplicity, the plugin does not maintain an open connection for receiving and responding to events. The “send message” command will simply send and disconnect. The “connect” command will simply check in, collect all offline (unread) messages, then disconnect. Put another way, you need to keep polling the server in 4D code to receive new messages.

structured yet extensible data: libstrophe can be used to create message, iq, error or presence stanzas (a stanza is a unit of structured data, an abstraction of XML tree nodes), but it can be also be used to create generic stanza to handle any kind of structured information. For simplicity, the plugin only supports sending and receiving message stanzas. Of course, you can put any kind of data in the message body. You can also add any number of custom attributes.

between any two or more network entities: This is the focus of this plugin. You can depend on existing network of XMPP servers to broker your message from one 4D to another. You can also depend on those servers to queue your messages.

Get started

You need 1 or more XMPP servers to relay your messages.

For example, you could use ejabberd Community Server on Mac.

• Install homebrew

• Install ejabberd

brew install ejabberd

• Setup TLS

openssl dhparam -out dh2048.pem 2048

openssl genrsa -out localhost-ejabberd.key 2048

openssl req -out localhost-ejabberd.csr -key localhost-ejabberd.key -new -sha256

openssl x509 -req -days 365 -in localhost-ejabberd.csr -signkey localhost-ejabberd.key -out localhost-ejabberd.crt

cat localhost-ejabberd.crt >  localhost-ejabberd.pem
cat localhost-ejabberd.key >> localhost-ejabberd.pem

Edit /usr/local/etc/ejabberd/ejabberd.yml

#certfiles:
#  - "/etc/letsencrypt/live/localhost/fullchain.pem"
#  - "/etc/letsencrypt/live/localhost/privkey.pem"

listen:
  -
    port: 5222
    ip: "::"
    module: ejabberd_c2s
    max_stanza_size: 262144
    shaper: c2s_shaper
    access: c2s
    certfile: "/usr/local/etc/ejabberd/localhost-ejabberd.pem"
    starttls: true
    starttls_required: true
    tls_compression: false
    dhfile: "/usr/local/etc/ejabberd/dh2048.pem"

• Start ejabberd

ejabberdctl start

• Create a user

ejabberdctl register jimmy.kimmel localhost abc

• Create another user

ejabberdctl register jimmy.fallon localhost nbc

• Create another user for admin

ejabberdctl register administrator localhost cbs

• Login as admin at http://localhost:5280/admin/

• Edit ejabberd.yml

acl:
local:
  user_regexp: ""
loopback:
  ip:
    - "127.0.0.0/8"
    - "::1/128"
admin:
  user:
    - "administrator": "localhost"

• Restart server

ejabberdctl restart

• Refresh browser

• Test that the server is working, with an XMPP client

For example, you could use Adium on Mac.

---

Send a message

$params:=New object

$params.jid:="jimmy.fallon@localhost/m"
$params.password:="nbc"
$params.host:="localhost"

  //message stanza
$message:=New object(\
"body";"Hello!";\
"type";"chat";\
"id";Generate UUID;\
"to";"jimmy.kimmel@localhost")

$status:=xmpp send message ($params;$message)

status:=xmpp send message (params;message)

params object

Property	Type	Description
jid	TEXT	required
password	TEXT	required
host	TEXT	required
logLevel	LONGINT	default=XMPP_LEVEL_DEBUG
keepAlive	BOOLEAN	default=false
keepAliveTimeout	LONGINT	default=60
keepAliveInterval	LONGINT	default=1
timeout	LONGINT	default=20
disableTLS	BOOLEAN	default=false
mandatoryTLS	BOOLEAN	default=true
legacyTLS	BOOLEAN	default=false
trustTLS	BOOLEAN	default=true
enableLegacyAuth	BOOLEAN	default=false

message object

Property	Type	Description
body	TEXT	required
to	TEXT	required
type	TEXT	default=”chat”
ns	TEXT	default=”jabber:client”
from	TEXT	default=jid
xml:lang	TEXT	default=”en”
id	TEXT	default=xmpp_uuid_gen()

status object

Property	Type	Description
log	COLLECTION

• Example

Message sent to an offline peer is banked.

---

Receive messages

$params:=New object

$params.jid:="jimmy.kimmel@localhost/m"
$params.password:="abc"
$params.host:="localhost"

$status:=xmpp connect ($params)

status:=xmpp connect (params;message)

status object

Property	Type	Description
log	COLLECTION
messages	COLLECTION

message object

Property	Type	Description
body	TEXT
to	TEXT
type	TEXT
ns	TEXT
from	TEXT
id	TEXT