whatsxmpp/xmpp.lisp
eta e4e9aa0ec1 Don't break on nodes with whitespace/text in between
- The child nodes of a given node can include both text nodes and
  actual XML element nodes. Trying to pass a text node to something
  like DOM:TAG-NAME signals an error condition.
- To avoid this, use DOM:ELEMENT-P and the CHILD-ELEMENTS helper
  function to filter lists of nodes down to elements where elements
  are expected.
2020-07-31 15:45:07 +01:00

166 lines
6.7 KiB
Common Lisp

(in-package :whatsxmpp)
(defun make-message-uuid (comp)
(with-accessors ((promises component-promises)) comp
(let ((uuid (string-downcase (write-to-string (uuid:make-v4-uuid))))
(promise (make-promise)))
(setf (gethash uuid promises) promise)
(values uuid promise))))
(defmacro with-stanza ((comp stanza-name &key type from to id) &body body)
(alexandria:with-gensyms (uuid ret from-sym id-sym)
`(with-component-xml-output (,comp)
(let ((,from-sym (or ,from (component-name ,comp)))
(,id-sym ,id))
(multiple-value-bind (,uuid ,ret)
(if ,id-sym
(values ,id-sym ,id-sym)
(make-message-uuid ,comp))
(cxml:with-element ,stanza-name
(cxml:attribute "from" ,from-sym)
(cxml:attribute "id" ,uuid)
,(when to
`(cxml:attribute "to" ,to))
,(when type
`(cxml:attribute "type" ,type))
,@body)
,ret)))))
(defmacro with-iq ((comp to &key (type "get") from id) &body body)
"Send an IQ stanza (of type TYPE) on the COMP component, from the JID FROM (default: component name) to the JID TO, with BODY specifying further CXML commands to make up the body of the stanza. Returns a promise."
`(with-stanza (,comp "iq"
:type ,type
:to ,to
:from ,from
:id ,id)
,@body))
(defmacro with-message ((comp to &key (type "chat") from id) &body body)
"Send a message stanza (of type TYPE) on the COMP component. Semantics the same as WITH-IQ, except for the fact that message stanzas don't normally prompt a response."
`(with-stanza (,comp "message"
:type ,type
:to ,to
:from ,from
:id ,id)
,@body))
(defmacro with-presence ((comp to &key type from id) &body body)
"Send a presence stanza (of type TYPE) on the COMP component. Semantics the same as WITH-IQ, except for the fact that presence stanzas don't normally prompt a response."
`(with-stanza (,comp "presence"
:type ,type
:to ,to
:from ,from
:id ,id)
,@body))
(defun get-node-named (nodes name)
"Finds the node with tag name NAME in NODES, returning NIL if none was found."
(flet ((is-the-node (node) (and (dom:element-p node) (equal (dom:tag-name node) name))))
(find-if #'is-the-node nodes)))
(defun get-node-with-xmlns (nodes xmlns)
"Finds the node with XML namespace XMLNS in NODES, returning NIL if none was found."
(flet ((is-the-node (node) (and (dom:element-p node) (equal (dom:get-attribute node "xmlns") xmlns))))
(find-if #'is-the-node nodes)))
(defun handle-stream-error (comp stanza)
(flet ((is-error-node (node)
(equal (dom:namespace-uri node) +streams-ns+))
(is-text-node (node)
(equal (dom:tag-name node) "text")))
(let* ((children (child-elements stanza))
(error-node (find-if #'is-error-node children))
(error-text-node (find-if #'is-text-node children))
(error-name (dom:tag-name error-node))
(error-text (when error-text-node
(dom:node-value (elt (dom:child-nodes error-text-node) 0)))))
(warn "Stream error of type ~A encountered: ~A" error-name error-text)
(emit :stream-error comp error-name error-text stanza))))
(define-condition stanza-error (error)
((defined-condition
:initarg :defined-condition
:accessor stanza-error-condition)
(type
:initarg :type
:accessor stanza-error-type)
(text
:initarg :text
:initform nil
:accessor stanza-error-text)
(raw
:initarg :raw
:initform nil
:accessor stanza-error-raw))
(:report (lambda (err stream)
(with-slots (defined-condition type text) err
(format stream "~A (type ~A): ~A" defined-condition type text)))))
(defun extract-stanza-error (stanza)
"Extracts a STANZA-ERROR from the given STANZA, which must contain an <error/> element conforming to RFC 6120 § 8.3."
(flet ((is-error-condition-node (node)
(equal (dom:namespace-uri node) +stanzas-ns+))
(is-error-node (node)
(equal (dom:tag-name node) "error"))
(is-text-node (node)
(and (equal (dom:namespace-uri node) +stanzas-ns+) (equal (dom:tag-name node) "text"))))
(let* ((error-node (find-if #'is-error-node (child-elements stanza)))
(error-children (child-elements error-node))
(type (dom:get-attribute error-node "type"))
(condition-node (find-if #'is-error-condition-node error-children))
(condition-name (dom:tag-name condition-node))
(text-node (find-if #'is-text-node error-children))
(text (when text-node
(dom:node-value (elt (dom:child-nodes text-node) 0)))))
(make-condition 'stanza-error
:raw error-node
:defined-condition condition-name
:type type
:text text))))
(defun send-stanza-error (comp &key id to from e stanza-type)
"Send E (a STANZA-ERROR) as an error response to a stanza of type STANZA."
(with-component-xml-output (comp)
(cxml:with-element stanza-type
(cxml:attribute "type" "error")
(cxml:attribute "id" id)
(cxml:attribute "from" from)
(cxml:attribute "to" to)
(cxml:with-element "error"
(cxml:attribute "type" (stanza-error-type e))
(cxml:with-element (stanza-error-condition e)
(cxml:attribute "xmlns" +stanzas-ns+))
(when (stanza-error-text e)
(cxml:with-element "text"
(cxml:text (stanza-error-text e))))))))
(defun parse-jid (jid)
"Parse JID, returning the multiple values HOSTNAME, LOCALPART and RESOURCE."
(declare (type string jid))
(let ((at-pos (position #\@ jid))
(slash-pos (position #\/ jid)))
(cond
((and (not slash-pos) (not at-pos))
(values jid nil nil))
((and slash-pos (not at-pos))
(multiple-value-bind (hostname resource)
(whatscl::split-at jid slash-pos)
(values hostname nil resource)))
((and (not slash-pos) at-pos)
(multiple-value-bind (localpart hostname)
(whatscl::split-at jid at-pos)
(values hostname localpart nil)))
(t
(multiple-value-bind (rest resource)
(whatscl::split-at jid slash-pos)
(multiple-value-bind (localpart hostname)
(whatscl::split-at rest at-pos)
(values hostname localpart resource)))))))
(defun strip-resource (jid)
"Strips a resource from JID, if there is one, returning the bare JID."
(let ((slash-pos (position #\/ jid)))
(if slash-pos
(whatscl::split-at jid slash-pos)
jid)))