This library is an implementation of the XMPP protocol to be used in Flutter Multiplatform apps.
Note: THIS LIBRARY IS BEING DEVELOPED FOR A PERSONAL USE CASE AND IT'S NOT YET READY FOR THE PUBLIC. USE WITH CAUTION. WHEN THIS CODEBASE BECOMES MORE STABLE IT WILL BE DEVELOPED AS AN OPEN SOURCE PROJECT
XMPP is a messaginc protocol based on XML. Its fundamental elements are defined in the Extensible Messaging and Presence Protocol (XMPP): Core RFC document (RFC6120).
According to that document, XMPP is defined as follows:
The Extensible Messaging and Presence Protocol (XMPP) is an application profile of the Extensible Markup Language (XML) that enables the near-real-time exchange of structured yet extensible data between any two or more network entities. This document defines XMPP's core protocol methods: setup and teardown of XML streams, channel encryption, authentication, error handling, and communication primitives for messaging, network availability ("presence"), and request-response interactions.
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Determine the IP address and port at which to connect, typically based on resolution of a fully qualified domain name
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Open a Transmission Control Protocol [TCP] connection
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Open an XML stream over TCP
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Preferably negotiate Transport Layer Security [TLS] for channel encryption
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Authenticate using a Simple Authentication and Security Layer [SASL] mechanism
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Bind a resource to the stream
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Exchange an unbounded number of XML stanzas with other entities on the network
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Close the XML stream
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Close the TCP connection
JIDs are the basic form of identity in XMPP implementations. It usually describes a particular account that belongs to a server but can be used in different ways. The details of the JID address format can be found on RFC6122.
- domainpart: In this case, domainpart references to the server being used. It should be an IP Address or a FQDN that can be resolved to an IP Address to connect to using the TCP protocol.
- localpart@domainpart: This case describes a specific account (with localpart) connected to a specific XMPP server (referenced by domainpart). Local Parts usually refer to accounts or device IDs depending the use of the implementation.
- localpart@domainpart/resourcepart: This case is considered a "full JID" and describes a particular resource from a server. Typically a resourcepart uniquely identifies a specific connection (e.g., a device or location) or object (e.g., an occupant in a multi-user chat room) belonging to the entity associated with an XMPP localpart at a domain (i.e., <localpart@domainpart/resourcepart>).
The term "bare JID" refers to an XMPP address of the form localpart@domainpart (for an account at a server) or of the form (for a server).
The term "full JID" refers to an XMPP address of the form <localpart@domainpart/resourcepart> (for a particular authorized client or device associated with an account) or of the form <domainpart/resourcepart> (for a particular resource or script associated with a server).
When using XEMPI, you can create JIDs using the XempiJid class. The only parameter required is the Domain Part as per the specification.
XempiJid domainPartJid = XempiJid(domainPart: 'myserver.com');
print(domainPartJid) // prints "myserver.com"
XempiJid bareJid = XempiJid(localPart: 'myusername', domainPart: 'myserver.com');
print(bareJid) // prints "myusername@myserver.com"
XempiJid fullJid = XempiJid(
localPart: 'myusername',
domainPart: 'myserver.com',
resourcePart: 'connectionID'
);
print(fullJid) // prints "myusername@myserver.com/connectionID"A Stanza is a message sent over the XMPP "XML Stream". There are three types of Stanzas:
- Message
- Presence
- IQ (short for Info/Query)
XMPP defines specific parts of the implementation as Extensions to the protocol also called XEPs.
- [XMPP-IM] Saint-Andre, P., "Extensible Messaging and Presence Protocol (XMPP): Instant Messaging and Presence", RFC 6121
- [XEP-0001] Saint-Andre, P., "XMPP Extension Protocols", XSF XEP 0001, March 2010.