From c275a245970eb52549981df1508eee54b736884c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Micka=C3=ABl=20R=C3=A9mond?= Date: Fri, 16 Dec 2005 16:33:42 +0000 Subject: Documentation update, code clean-up and Makefile improvement. SVN Revision: 473 --- doc/dev.html | 326 ++++++++++++++++++++++++++++++++++++----------------------- 1 file changed, 202 insertions(+), 124 deletions(-) (limited to 'doc/dev.html') diff --git a/doc/dev.html b/doc/dev.html index 22ee142bb..65a85172a 100644 --- a/doc/dev.html +++ b/doc/dev.html @@ -1,99 +1,186 @@ -Ejabberd Developers Guide - - + + +Ejabberd 1.0.0 Developers Guide + + + + + - + +
+
+ - -

Ejabberd Developers Guide

- -

Alexey Shchepin
+ + +
+
Ejabberd 1.0.0 Developers Guide
+
Alexey Shchepin
`mailto:alexey@sevcom.net`
-`xmpp:aleksey@jabber.ru`
- -
August 21, 2005
- +`xmpp:aleksey@jabber.ru`

+
+
+ -

+

+ +
I can thoroughly recommend ejabberd for ease of setup – + Kevin Smith, Current maintainer of the Psi project
+ - +

- -

1 Introduction -

-1.1 How it works -

-1.1.1 Router -
1.1.2 Local Router -
1.1.3 Session Manager -
1.1.4 S2S Manager +
- +1.1 Key Features +
- 1.2 Additional Features
+
2 How it works +
- +2.1 Router +
- 2.2 Local Router +
- 2.3 Session Manager +
- 2.4 S2S Manager
-
2 XML representation -
3 Module xml -
4 Module xml_stream -

5 ejabberd modules -

-5.1 gen_mod behaviour -
5.2 Module gen_iq_handler -
5.3 Services +
3 XML representation +
4 Module xml +
5 Module xml_stream +
6 ejabberd modules +

1 Introduction

- -ejabberd is a Free and Open Source fault-tolerant distributed Jabber -server. It is written mostly in Erlang.
+ + +ejabberd is a free (GPL) distributed fault-tolerant Jabber/XMPP server and is mainly written in Erlang.

-The main features of ejabberd are: -

-Works on most of popular platforms: *nix (tested on Linux, FreeBSD and - NetBSD) and Win32 -
Distributed: You can run ejabberd on a cluster of machines to let all of - them serve one Jabber domain. -
Fault-tolerance: You can setup an ejabberd cluster so that all the - information required for a properly working service will be stored - permanently on more than one node. This means that if one of the nodes - crashes, then the others will continue working without disruption. - You can also add or replace nodes ``on the fly''. -
Support for virtual hosting -
Built-in Multi-User Chat service -
Built-in IRC transport -
Built-in Publish-Subscribe service -
Built-in Jabber Users Directory service based on users vCards -
Built-in web-based administration interface -
Built-in HTTP Polling service -
SSL support -
Support for LDAP authentication -
Ability to interface with external components (JIT, MSN-t, Yahoo-t, etc.) -
Migration from jabberd14 is possible -
Mostly XMPP-compliant -
Support for Service Discovery. -
Support for Statistics Gathering. -

Support for xml:lang +ejabberd is designed to be a stable, standards compliant, and feature rich Jabber/XMPP server.
+
+ejabberd is suitable for small servers, whether they need to be scalable or not, as well as extremely big servers.
+
+ + +

1.1 Key Features

+ + + +ejabberd is: +

+Multiplatform: ejabberd runs under Microsoft Windows and Unix derived systems such as Linux, FreeBSD and NetBSD.
+
+
Distributed: You can run ejabberd on a cluster of machines and all of them will serve one Jabber domain. When you need more capacity you can simply add a new cheap node to your cluster. Accordingly, you do not need to buy an expensive high-end machine to support tens of thousands concurrent users.
+
+
Fault-tolerant: You can deploy an ejabberd cluster so that all the information required for a properly working service will be replicated permanently on all nodes. This means that if one of the nodes crashes, the others will continue working without disruption. In addition, nodes also can be added or replaced “on the fly”.
+
+
Administrator Friendly: ejabberd is built on top of the Open Source Erlang. As a result you do not need to install an external database, an external web server, amongst others because everything is already included, and ready to run out of the box. Other administrator benefits include: +
- +Comprehensive documentation. +
- Straightforward installers for Windows and Linux. +
- Web interface for administration tasks. +
- Shared Roster groups. +
- Command line administration tool. +
- Can integrate with existing authentication mechanisms. +
- Capability to send announce messages. +
+
+
Internationalized: ejabberd leads in internationalization. Hence it is very well suited in a globalized world. Related features are: +
- +Translated in 11 languages. +
- Support for IDNA. +
+
+
Open Standards: ejabberd is the first Open Source Jabber server claiming to fully comply to the XMPP standard. +
- +Fully XMPP compliant +
- XML-based protocol +
- Many JEPs supported. +

+ + +

1.2 Additional Features

+ + + +Besides common Jabber server features, ejabberd comes with a wide range of other features: +

+Modular: ejabberd's modular architecture allows easy customization: +
- +Load only the modules you want. +
- Extend ejabberd with your own custom modules. +
+
Security +
- +SASL and STARTTLS for c2s and s2s connections. +
- STARTTLS and Dialback s2s connections. +
- Obsolete SSL for c2s connections also supported. +
- Web interface accessible via HTTPS secure access. +
+
Databases +
- +Native PostgreSQL support. +
- Mnesia. +
- ODBC data storage support. +
+
Authentication +
- +LDAP. +
- External Authentication script. +
- Internal Authentication. +
+
The ability to interface via external components with networks such as: +
- +AIM +
- ICQ +
- MSN +
+
Others +
- +IPv6 support both for c2s and s2s connections. +
- Support for virtual hosting. +
- HTTP Polling service +
- Multi-User Chat module. +
- IRC transport. +
- Publish-Subscribe component. +
- Users Directory based on users vCards. +
- Statistics via Statistics Gathering (JEP-0039). +

- + -

1.1 How it works

2 How it works

A Jabber domain is served by one or more ejabberd nodes. These nodes can @@ -105,15 +192,15 @@ needed because all nodes exchange information about connected users, S2S connections, registered services, etc...

Each ejabberd node have following modules: -

router; -
local router. -
session manager; -
S2S manager; +
local router. +
session manager; +
S2S manager;

- + -

1.1.1 Router

2.1 Router

This module is the main router of Jabber packets on each node. It routes them based on their destinations domains. It has two tables: local and global @@ -123,26 +210,26 @@ searches in global table, and is routed to the appropriate ejabberd nod process. If it does not exists in either tables, then it sent to the S2S manager.

- + -

1.1.2 Local Router

2.2 Local Router

This module routes packets which have a destination domain equal to this server name. If destination JID has a non-empty user part, then it routed to the session manager, else it is processed depending on it's content.

- + -

1.1.3 Session Manager

2.3 Session Manager

This module routes packets to local users. It searches for what user resource packet must be sended via presence table. If this resource is connected to this node, it is routed to C2S process, if it connected via another node, then the packet is sent to session manager on that node.

- + -

1.1.4 S2S Manager

2.4 S2S Manager

This module routes packets to other Jabber servers. First, it checks if an open S2S connection from the domain of the packet source to the domain of @@ -153,11 +240,11 @@ does not exist, then it is opened and registered.

-

2 XML representation

3 XML representation

Each XML stanza is represented as the following tuple: -

+ XMLElement = {xmlelement, Name, Attrs, [ElementOrCDATA]}
         Name = string()
         Attrs = [Attr]
@@ -167,12 +254,12 @@ XMLElement = {xmlelement, Name, Attrs, [ElementOrCDATA]}
         ElementOrCDATA = XMLElement | CDATA
         CDATA = {xmlcdata, string()}
 E. g. this stanza:
-+ <message to='test@conference.example.org' type='groupchat'>
   <body>test</body>
 </message>
 is represented as the following structure:
-+ {xmlelement, "message",
     [{"to", "test@conference.example.org"},
      {"type", "groupchat"}],
@@ -182,29 +269,28 @@ XMLElement = {xmlelement, Name, Attrs, [ElementOrCDATA]}
 
 
 
-3  Module xml

+4  Module xml

 
 
-
-element_to_string(El) -> string()

-+
element_to_string(El) -> string()
+ El = XMLElement
 
Returns string representation of XML stanza El.

 

-
crypt(S) -> string()

-+
crypt(S) -> string()
+ S = string()
 
Returns string which correspond to S with encoded XML special
  characters.

 

-
remove_cdata(ECList) -> EList

-+
remove_cdata(ECList) -> EList
+ ECList = [ElementOrCDATA]
 EList = [XMLElement]
 
EList is a list of all non-CDATA elements of ECList.

 

-
get_path_s(El, Path) -> Res

-+
get_path_s(El, Path) -> Res
+ El = XMLElement
 Path = [PathItem]
 PathItem = PathElem | PathAttr | PathCDATA
@@ -215,17 +301,16 @@ Name = string()
 Res = string() | XMLElement
 
If Path is empty, then returns El. Else sequentially
  consider elements of Path. Each element is one of:
- 
- {elem, Name}
 Name is name of subelement of
+ 
{elem, Name} Name is name of subelement of
  El, if such element exists, then this element considered in
  following steps, else returns empty string.
- 
{attr, Name}
 If El have attribute Name, then
+ 
{attr, Name} If El have attribute Name, then
  returns value of this attribute, else returns empty string.
- 
cdata
 Returns CDATA of El.
+ 
cdata Returns CDATA of El.
  


 

-
TODO:

-+
TODO:
+          get_cdata/1, get_tag_cdata/1
          get_attr/2, get_attr_s/2
          get_tag_attr/2, get_tag_attr_s/2
@@ -233,12 +318,11 @@ Res = string() | XMLElement
 
 
 
-4  Module xml_stream

+5  Module xml_stream

 
 
-
-parse_element(Str) -> XMLElement | {error, Err}

-+
parse_element(Str) -> XMLElement | {error, Err}
+ Str = string()
 Err = term()
 
Parses Str using XML parser, returns either parsed element or error
@@ -246,28 +330,27 @@ Err = term()
 
 
 
-5  ejabberd modules

+6  ejabberd modules

 
 
-
+
 
-5.1  gen_mod behaviour

+6.1  gen_mod behaviour

 
 
 TBD

 

-
+
 
-5.2  Module gen_iq_handler

+6.2  Module gen_iq_handler

 
 
 The module gen_iq_handler allows to easily write handlers for IQ packets
 of particular XML namespaces that addressed to server or to users bare JIDs.

 

 In this module the following functions are defined:
-
-add_iq_handler(Component, Host, NS, Module, Function, Type)

-+
add_iq_handler(Component, Host, NS, Module, Function, Type)
+ Component = Module = Function = atom()
 Host = NS = string()
 Type = no_queue | one_queue | parallel
@@ -275,24 +358,22 @@ Type = no_queue | one_queue | parallel
  virtual host Host that contain child of namespace NS in
  Component. Queueing discipline is Type. There are at least
  two components defined:
- 
- ejabberd_local
 Handles packets that addressed to server JID;
- 
ejabberd_sm
 Handles packets that addressed to users bare JIDs.
+ 
ejabberd_local Handles packets that addressed to server JID;
+ 
ejabberd_sm Handles packets that addressed to users bare JIDs.
  
-
remove_iq_handler(Component, Host, NS)

-+
remove_iq_handler(Component, Host, NS)
+ Component = atom()
 Host = NS = string()
 
Removes IQ handler on virtual host Host for namespace NS from
  Component.
 
 Handler function must have the following type:
-
-Module:Function(From, To, IQ)

-+
Module:Function(From, To, IQ)
+ From = To = jid()
 
-+ -module(mod_cputime).
 
 -behaviour(gen_mod).
@@ -330,13 +411,13 @@ process_local_iq(From, To, {iq, ID, Type, XMLNS, SubEl}) ->
 
 
 
-5.3  Services

+6.3  Services

 
 
 TBD

 

 TODO: use proc_lib
-+ -module(mod_echo).
 
 -behaviour(gen_mod).
@@ -375,9 +456,6 @@ stop(Host) ->
 
 
 
-
-This document was translated from L^AT_EX by
-H^EV^EA.
-
-
+
This document was translated from L^AT_EX by
+H^EV^EA.
 
-- 
cgit v1.2.3

Ejabberd Developers Guide

Ejabberd 1.0.0 Developers Guide

Alexey Shchepin
`mailto:alexey@sevcom.net`
-`xmpp:aleksey@jabber.ru`

August 21, 2005

Contents

Table of Contents

1 Introduction

1 Introduction

1.1 Key Features

1.2 Additional Features

1.1 How it works

2 How it works

1.1.1 Router

2.1 Router

1.1.2 Local Router

2.2 Local Router

1.1.3 Session Manager

2.3 Session Manager

1.1.4 S2S Manager

2.4 S2S Manager

2 XML representation

3 XML representation

3 Module `xml`

4 Module `xml`

4 Module `xml_stream`

5 Module `xml_stream`

5 `ejabberd` modules

6 `ejabberd` modules

5.1 `gen_mod` behaviour

6.1 gen_mod behaviour

5.2 Module `gen_iq_handler`

6.2 Module gen_iq_handler

5.3 Services

6.3 Services

Ejabberd Developers Guide

Alexey Shchepin + + + +Ejabberd 1.0.0 Developers Guide +Alexey Shchepin mailto:alexey@sevcom.net -xmpp:aleksey@jabber.ru - -August 21, 2005 - +xmpp:aleksey@jabber.ru + + + - + + +I can thoroughly recommend ejabberd for ease of setup – + Kevin Smith, Current maintainer of the Psi project + - +

Ejabberd 1.0.0 Developers Guide

Alexey Shchepin mailto:alexey@sevcom.net -xmpp:aleksey@jabber.ru

August 21, 2005

Contents

Table of Contents

1 Introduction

1 Introduction

1.1 Key Features

1.2 Additional Features

1.1 How it works

2 How it works

1.1.1 Router

2.1 Router

1.1.2 Local Router

2.2 Local Router

1.1.3 Session Manager

2.3 Session Manager

1.1.4 S2S Manager

2.4 S2S Manager

2 XML representation

3 XML representation

3 Module xml

4 Module xml

4 Module xml_stream

5 Module xml_stream

5 ejabberd modules

6 ejabberd modules

5.1 gen_mod behaviour

6.1 gen_mod behaviour

5.2 Module gen_iq_handler

6.2 Module gen_iq_handler

5.3 Services

6.3 Services

Alexey Shchepin
`mailto:alexey@sevcom.net`
-`xmpp:aleksey@jabber.ru`

3 Module `xml`

4 Module `xml`

4 Module `xml_stream`

5 Module `xml_stream`

5 `ejabberd` modules

6 `ejabberd` modules

5.1 `gen_mod` behaviour

5.2 Module `gen_iq_handler`