internal

Documentation

Overview

Package internal provides non-exported functionality used by xmpp and its child packages.

Index

• Constants
• Variables
• func GetAttr(attr []xml.Attr, local string) string
• func LookupBOSH(ctx context.Context, client *http.Client, addr *jid.JID) (urls []string, err error)
• func LookupPort(network, service string) (int, error)
• func LookupService(service, network string, addr net.Addr) (addrs []*net.SRV, err error)
• func LookupWebsocket(ctx context.Context, client *http.Client, addr *jid.JID) (urls []string, err error)
• func RandomID() string
• type Link
• type StreamInfo
  • func ExpectNewStream(ctx context.Context, d xml.TokenReader, recv bool) (streamData StreamInfo, err error)
  • func SendNewStream(rw io.ReadWriter, s2s bool, version Version, lang string, ...) (StreamInfo, error)
• type Version
  • func MustParseVersion(s string) Version
  • func ParseVersion(s string) (Version, error)
  • func (v Version) Less(b Version) bool
  • func (v Version) MarshalXMLAttr(name xml.Name) (xml.Attr, error)
  • func (v Version) String() string
  • func (v *Version) UnmarshalXMLAttr(attr xml.Attr) error
• type XRD

Constants

const IDLen = 16

IDLen is the standard length of stanza identifiers in bytes.

const (
	// XMLHeader is an XML header like the one in encoding/xml but without a
	// newline at the end.
	XMLHeader = `<?xml version="1.0" encoding="UTF-8"?>`
)

Variables

var (
	DefaultVersion = Version{1, 0} // The default version to send.
	EmptyVersion   = Version{0, 9} // The value of a missing version attribute.
)

Common XMPP versions.

var (
	ErrNoServiceAtAddress = errors.New("This address does not offer the requested service")
)

Errors related to address and service lookups.

Functions

func GetAttr

func GetAttr(attr []xml.Attr, local string) string

GetAttr returns the value of the first attribute with the provided local name from a list of attributes or an empty string if no such attribute exists.

func LookupBOSH

func LookupBOSH(ctx context.Context, client *http.Client, addr *jid.JID) (urls []string, err error)

LookupBOSH discovers BOSH endpoints that are valid for the given address using DNS TXT records and Web Host Metadata as described in XEP-0156. If client is nil, only DNS is queried.

func LookupPort

func LookupPort(network, service string) (int, error)

LookupPort returns the default port for the provided network and service using net.LookupPort. If the provided service is one of xmpp-client, xmpp-server, or xmpp-bosh and it is not found by net.LookupPort, a default value is returned.

func LookupService

func LookupService(service, network string, addr net.Addr) (addrs []*net.SRV, err error)

LookupService looks for an XMPP service hosted by the given address. It returns addresses from SRV records or the default domain (as a fake SRV record) if no real records exist. Service should be one of "xmpp-client" or "xmpp-server".

func LookupWebsocket

func LookupWebsocket(ctx context.Context, client *http.Client, addr *jid.JID) (urls []string, err error)

LookupWebsocket discovers websocket endpoints that are valid for the given address using DNS TXT records and Web Host Metadata as described in XEP-0156. If client is nil, only DNS is queried.

func RandomID

func RandomID() string

RandomID generates a new random identifier of length IDLen. If the OS's entropy pool isn't initialized, or we can't generate random numbers for some other reason, panic.

Types

type Link

type Link struct {
	Rel  string `xml:"rel,attr"`
	Href string `xml:"href,attr"`
}

Link is an individual hyperlink in an XRD document.

type StreamInfo

type StreamInfo struct {
	// contains filtered or unexported fields
}

StreamInfo contains metadata extracted from a stream start token.

func ExpectNewStream

func ExpectNewStream(ctx context.Context, d xml.TokenReader, recv bool) (streamData StreamInfo, err error)

ExpectNewStream reads a token from d and expects that it will be a new stream start token. If not, an error is returned. It then handles feature negotiation for the new stream. If an XML header is discovered instead, it is skipped.

func SendNewStream

func SendNewStream(rw io.ReadWriter, s2s bool, version Version, lang string, location, origin, id string) (StreamInfo, error)

SendNewStream sends a new XML header followed by a stream start element on the given io.Writer. We don't use an xml.Encoder both because Go's standard library xml package really doesn't like the namespaced stream:stream attribute and because we can guarantee well-formedness of the XML with a print in this case and printing is much faster than encoding. Afterwards, clear the StreamRestartRequired bit and set the output stream information.

type Version

type Version struct {
	Major uint8
	Minor uint8
}

Version is a version of XMPP.

func MustParseVersion

func MustParseVersion(s string) Version

MustParseVersion parses a version string and panics if an error is returned.

func ParseVersion

func ParseVersion(s string) (Version, error)

ParseVersion parses a string of the form "Major.Minor" into a Version struct or returns an error.

func (Version) Less

func (v Version) Less(b Version) bool

Less compares the major and minor version numbers, returning true if a is less than b.

func (Version) MarshalXMLAttr

func (v Version) MarshalXMLAttr(name xml.Name) (xml.Attr, error)

MarshalXMLAttr satisfies the MarshalerAttr interface and marshals the version as an XML attribute using its string representation.

func (Version) String

func (v Version) String() string

Prints a string representation of the XMPP version in the form "Major.Minor".

func (*Version) UnmarshalXMLAttr

func (v *Version) UnmarshalXMLAttr(attr xml.Attr) error

UnmarshalXMLAttr satisfies the UnmarshalerAttr interface and unmarshals an XML attribute into a valid XMPP version (or returns an error).

type XRD

type XRD struct {
	XMLName xml.Name `xml:"http://docs.oasis-open.org/ns/xri/xrd-1.0 XRD"`
	Links   []Link   `xml:"Link"`
}

XRD represents an Extensible Resource Descriptor document of the form:

<?xml version='1.0' encoding=utf-9'?>
<XRD xmlns='http://docs.oasis-open.org/ns/xri/xrd-1.0'>
  …
  <Link rel="urn:xmpp:alt-connections:xbosh"
        href="https://web.example.com:5280/bosh" />
  <Link rel="urn:xmpp:alt-connections:websocket"
        href="wss://web.example.com:443/ws" />
  …
</XRD>

as defined by RFC 6415 and OASIS.XRD-1.0.