Daniel Veillard | d2190fa | 2010-09-30 13:58:22 +0200 | [diff] [blame] | 1 | <?xml version="1.0" encoding="UTF-8"?> |
Daniel Veillard | 1177ca4 | 2003-04-26 22:29:54 +0000 | [diff] [blame] | 2 | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> |
Daniel Veillard | d2190fa | 2010-09-30 13:58:22 +0200 | [diff] [blame] | 3 | <html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><link rel="SHORTCUT ICON" href="/favicon.ico" /><style type="text/css"> |
Daniel Veillard | 373a475 | 2002-02-21 14:46:29 +0000 | [diff] [blame] | 4 | TD {font-family: Verdana,Arial,Helvetica} |
| 5 | BODY {font-family: Verdana,Arial,Helvetica; margin-top: 2em; margin-left: 0em; margin-right: 0em} |
| 6 | H1 {font-family: Verdana,Arial,Helvetica} |
| 7 | H2 {font-family: Verdana,Arial,Helvetica} |
| 8 | H3 {font-family: Verdana,Arial,Helvetica} |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 9 | A:link, A:visited, A:active { text-decoration: underline } |
Daniel Veillard | 28fdf8b | 2011-03-07 08:12:39 +0800 | [diff] [blame] | 10 | </style><title>Python and bindings</title></head><body bgcolor="#8b7765" text="#000000" link="#a06060" vlink="#000000"><table border="0" width="100%" cellpadding="5" cellspacing="0" align="center"><tr><td width="120"><a href="http://swpat.ffii.org/"><img src="epatents.png" alt="Action against software patents" /></a></td><td width="180"><a href="http://www.gnome.org/"><img src="gnome2.png" alt="Gnome2 Logo" /></a><a href="http://www.w3.org/Status"><img src="w3c.png" alt="W3C Logo" /></a><a href="http://www.redhat.com/"><img src="redhat.gif" alt="Red Hat Logo" /></a><div align="left"><a href="http://xmlsoft.org/"><img src="Libxml2-Logo-180x168.gif" alt="Made with Libxml2 Logo" /></a></div></td><td><table border="0" width="90%" cellpadding="2" cellspacing="0" align="center" bgcolor="#000000"><tr><td><table width="100%" border="0" cellspacing="1" cellpadding="3" bgcolor="#fffacd"><tr><td align="center"><h1>The XML C parser and toolkit of Gnome</h1><h2>Python and bindings</h2></td></tr></table></td></tr></table></td></tr></table><table border="0" cellpadding="4" cellspacing="0" width="100%" align="center"><tr><td bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="2" width="100%"><tr><td valign="top" width="200" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Developer Menu</b></center></td></tr><tr><td bgcolor="#fffacd"><form action="search.php" enctype="application/x-www-form-urlencoded" method="get"><input name="query" type="text" size="20" value="" /><input name="submit" type="submit" value="Search ..." /></form><ul><li><a href="index.html" style="font-weight:bold">Main Menu</a></li><li><a href="html/index.html" style="font-weight:bold">Reference Manual</a></li><li><a href="examples/index.html" style="font-weight:bold">Code Examples</a></li><li><a href="guidelines.html">XML Guidelines</a></li><li><a href="tutorial/index.html">Tutorial</a></li><li><a href="xmlreader.html">The Reader Interface</a></li><li><a href="ChangeLog.html">ChangeLog</a></li><li><a href="XSLT.html">XSLT</a></li><li><a href="python.html">Python and bindings</a></li><li><a href="architecture.html">libxml2 architecture</a></li><li><a href="tree.html">The tree output</a></li><li><a href="interface.html">The SAX interface</a></li><li><a href="xmlmem.html">Memory Management</a></li><li><a href="xmlio.html">I/O Interfaces</a></li><li><a href="library.html">The parser interfaces</a></li><li><a href="entities.html">Entities or no entities</a></li><li><a href="namespaces.html">Namespaces</a></li><li><a href="upgrade.html">Upgrading 1.x code</a></li><li><a href="threads.html">Thread safety</a></li><li><a href="DOM.html">DOM Principles</a></li><li><a href="example.html">A real example</a></li><li><a href="xml.html">flat page</a>, <a href="site.xsl">stylesheet</a></li></ul></td></tr></table><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>API Indexes</b></center></td></tr><tr><td bgcolor="#fffacd"><ul><li><a href="APIchunk0.html">Alphabetic</a></li><li><a href="APIconstructors.html">Constructors</a></li><li><a href="APIfunctions.html">Functions/Types</a></li><li><a href="APIfiles.html">Modules</a></li><li><a href="APIsymbols.html">Symbols</a></li></ul></td></tr></table><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Related links</b></center></td></tr><tr><td bgcolor="#fffacd"><ul><li><a href="http://mail.gnome.org/archives/xml/">Mail archive</a></li><li><a href="http://xmlsoft.org/XSLT/">XSLT libxslt</a></li><li><a href="http://phd.cs.unibo.it/gdome2/">DOM gdome2</a></li><li><a href="http://www.aleksey.com/xmlsec/">XML-DSig xmlsec</a></li><li><a href="ftp://xmlsoft.org/">FTP</a></li><li><a href="http://www.zlatkovic.com/projects/libxml/">Windows binaries</a></li><li><a href="http://opencsw.org/packages/libxml2">Solaris binaries</a></li><li><a href="http://www.explain.com.au/oss/libxml2xslt.html">MacOsX binaries</a></li><li><a href="http://lxml.de/">lxml Python bindings</a></li><li><a href="http://cpan.uwinnipeg.ca/dist/XML-LibXML">Perl bindings</a></li><li><a href="http://libxmlplusplus.sourceforge.net/">C++ bindings</a></li><li><a href="http://www.zend.com/php5/articles/php5-xmlphp.php#Heading4">PHP bindings</a></li><li><a href="http://sourceforge.net/projects/libxml2-pas/">Pascal bindings</a></li><li><a href="http://libxml.rubyforge.org/">Ruby bindings</a></li><li><a href="http://tclxml.sourceforge.net/">Tcl bindings</a></li><li><a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Bug Tracker</a></li></ul></td></tr></table></td></tr></table></td><td valign="top" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%"><tr><td><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table border="0" cellpadding="3" cellspacing="1" width="100%"><tr><td bgcolor="#fffacd"><p>There are a number of language bindings and wrappers available for |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 11 | libxml2, the list below is not exhaustive. Please contact the <a href="http://mail.gnome.org/mailman/listinfo/xml-bindings">xml-bindings@gnome.org</a> |
| 12 | (<a href="http://mail.gnome.org/archives/xml-bindings/">archives</a>) in |
| 13 | order to get updates to this list or to discuss the specific topic of libxml2 |
| 14 | or libxslt wrappers or bindings:</p><ul><li><a href="http://libxmlplusplus.sourceforge.net/">Libxml++</a> seems the |
| 15 | most up-to-date C++ bindings for libxml2, check the <a href="http://libxmlplusplus.sourceforge.net/reference/html/hierarchy.html">documentation</a> |
| 16 | and the <a href="http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/libxmlplusplus/libxml%2b%2b/examples/">examples</a>.</li> |
| 17 | <li>There is another <a href="http://libgdome-cpp.berlios.de/">C++ wrapper |
| 18 | based on the gdome2 bindings</a> maintained by Tobias Peters.</li> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 19 | <li>and a third C++ wrapper by Peter Jones <pjones@pmade.org> |
Daniel Veillard | 1177ca4 | 2003-04-26 22:29:54 +0000 | [diff] [blame] | 20 | <p>Website: <a href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 21 | </li> |
Daniel Veillard | d012f48 | 2007-08-22 17:36:57 +0000 | [diff] [blame] | 22 | <li>XML::LibXML <a href="http://cpan.uwinnipeg.ca/dist/XML-LibXML">Perl |
| 23 | bindings</a> are available on CPAN, as well as XML::LibXSLT |
| 24 | <a href="http://cpan.uwinnipeg.ca/dist/XML-LibXSLT">Perl libxslt |
| 25 | bindings</a>.</li> |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 26 | <li>If you're interested into scripting XML processing, have a look at <a href="http://xsh.sourceforge.net/">XSH</a> an XML editing shell based on |
| 27 | Libxml2 Perl bindings.</li> |
| 28 | <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides an |
| 29 | earlier version of the libxml/libxslt <a href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li> |
| 30 | <li>Gopal.V and Peter Minten develop <a href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of |
| 31 | C# libxml2 bindings.</li> |
| 32 | <li>Petr Kozelka provides <a href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue |
| 33 | libxml2</a> with Kylix, Delphi and other Pascal compilers.</li> |
| 34 | <li>Uwe Fechner also provides <a href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2 |
| 35 | implementation for Kylix2/D5/D6 from Borland.</li> |
| 36 | <li>There is <a href="http://libxml.rubyforge.org/">bindings for Ruby</a> |
| 37 | and libxml2 bindings are also available in Ruby through the <a href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module |
| 38 | maintained by Tobias Peters.</li> |
| 39 | <li>Steve Ball and contributors maintains <a href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for |
| 40 | Tcl</a>.</li> |
William M. Brack | 43a8729 | 2007-02-15 20:41:02 +0000 | [diff] [blame] | 41 | <li>libxml2 and libxslt are the default XML libraries for PHP5.</li> |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 42 | <li><a href="http://savannah.gnu.org/projects/classpathx/">LibxmlJ</a> is |
| 43 | an effort to create a 100% JAXP-compatible Java wrapper for libxml2 and |
| 44 | libxslt as part of GNU ClasspathX project.</li> |
| 45 | <li>Patrick McPhee provides Rexx bindings fof libxml2 and libxslt, look for |
| 46 | <a href="http://www.interlog.com/~ptjm/software.html">RexxXML</a>.</li> |
| 47 | <li><a href="http://www.satimage.fr/software/en/xml_suite.html">Satimage</a> |
| 48 | provides <a href="http://www.satimage.fr/software/en/downloads_osaxen.html">XMLLib |
| 49 | osax</a>. This is an osax for Mac OS X with a set of commands to |
| 50 | implement in AppleScript the XML DOM, XPATH and XSLT. Also includes |
| 51 | commands for Property-lists (Apple's fast lookup table XML format.)</li> |
| 52 | <li>Francesco Montorsi developped <a href="https://sourceforge.net/project/showfiles.php?group_id=51305&package_id=45182">wxXml2</a> |
| 53 | wrappers that interface libxml2, allowing wxWidgets applications to |
| 54 | load/save/edit XML instances.</li> |
| 55 | </ul><p>The distribution includes a set of Python bindings, which are guaranteed |
| 56 | to be maintained as part of the library in the future, though the Python |
| 57 | interface have not yet reached the completeness of the C API.</p><p>Note that some of the Python purist dislike the default set of Python |
Daniel Veillard | 28fdf8b | 2011-03-07 08:12:39 +0800 | [diff] [blame] | 58 | bindings, rather than complaining I suggest they have a look at <a href="http://lxml.de/">lxml the more pythonic bindings for libxml2 |
| 59 | and libxslt</a> and <a href="http://lxml.de/mailinglist/">check the mailing-list</a>.</p><p><a href="mailto:stephane.bidoul@softwareag.com">Stéphane Bidoul</a> |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 60 | maintains <a href="http://users.skynet.be/sbi/libxml-python/">a Windows port |
| 61 | of the Python bindings</a>.</p><p>Note to people interested in building bindings, the API is formalized as |
| 62 | <a href="libxml2-api.xml">an XML API description file</a> which allows to |
| 63 | automate a large part of the Python bindings, this includes function |
| 64 | descriptions, enums, structures, typedefs, etc... The Python script used to |
| 65 | build the bindings is python/generator.py in the source distribution.</p><p>To install the Python bindings there are 2 options:</p><ul><li>If you use an RPM based distribution, simply install the <a href="http://rpmfind.net/linux/rpm2html/search.php?query=libxml2-python">libxml2-python |
| 66 | RPM</a> (and if needed the <a href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python |
| 67 | RPM</a>).</li> |
| 68 | <li>Otherwise use the <a href="ftp://xmlsoft.org/libxml2/python/">libxml2-python |
| 69 | module distribution</a> corresponding to your installed version of |
| 70 | libxml2 and libxslt. Note that to install it you will need both libxml2 |
| 71 | and libxslt installed and run "python setup.py build install" in the |
| 72 | module tree.</li> |
| 73 | </ul><p>The distribution includes a set of examples and regression tests for the |
| 74 | python bindings in the <code>python/tests</code> directory. Here are some |
| 75 | excerpts from those tests:</p><h3>tst.py:</h3><p>This is a basic test of the file interface and DOM navigation:</p><pre>import libxml2, sys |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 76 | |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 77 | doc = libxml2.parseFile("tst.xml") |
| 78 | if doc.name != "tst.xml": |
| 79 | print "doc.name failed" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 80 | sys.exit(1) |
| 81 | root = doc.children |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 82 | if root.name != "doc": |
| 83 | print "root.name failed" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 84 | sys.exit(1) |
| 85 | child = root.children |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 86 | if child.name != "foo": |
| 87 | print "child.name failed" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 88 | sys.exit(1) |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 89 | doc.freeDoc()</pre><p>The Python module is called libxml2; parseFile is the equivalent of |
| 90 | xmlParseFile (most of the bindings are automatically generated, and the xml |
| 91 | prefix is removed and the casing convention are kept). All node seen at the |
| 92 | binding level share the same subset of accessors:</p><ul><li><code>name</code> : returns the node name</li> |
| 93 | <li><code>type</code> : returns a string indicating the node type</li> |
| 94 | <li><code>content</code> : returns the content of the node, it is based on |
| 95 | xmlNodeGetContent() and hence is recursive.</li> |
| 96 | <li><code>parent</code> , <code>children</code>, <code>last</code>, |
| 97 | <code>next</code>, <code>prev</code>, <code>doc</code>, |
| 98 | <code>properties</code>: pointing to the associated element in the tree, |
| 99 | those may return None in case no such link exists.</li> |
| 100 | </ul><p>Also note the need to explicitly deallocate documents with freeDoc() . |
| 101 | Reference counting for libxml2 trees would need quite a lot of work to |
| 102 | function properly, and rather than risk memory leaks if not implemented |
| 103 | correctly it sounds safer to have an explicit function to free a tree. The |
| 104 | wrapper python objects like doc, root or child are them automatically garbage |
| 105 | collected.</p><h3>validate.py:</h3><p>This test check the validation interfaces and redirection of error |
| 106 | messages:</p><pre>import libxml2 |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 107 | |
Daniel Veillard | 63d8314 | 2002-05-20 06:51:05 +0000 | [diff] [blame] | 108 | #deactivate error messages from the validation |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 109 | def noerr(ctx, str): |
| 110 | pass |
| 111 | |
| 112 | libxml2.registerErrorHandler(noerr, None) |
| 113 | |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 114 | ctxt = libxml2.createFileParserCtxt("invalid.xml") |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 115 | ctxt.validate(1) |
| 116 | ctxt.parseDocument() |
| 117 | doc = ctxt.doc() |
| 118 | valid = ctxt.isValid() |
| 119 | doc.freeDoc() |
| 120 | if valid != 0: |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 121 | print "validity check failed"</pre><p>The first thing to notice is the call to registerErrorHandler(), it |
| 122 | defines a new error handler global to the library. It is used to avoid seeing |
| 123 | the error messages when trying to validate the invalid document.</p><p>The main interest of that test is the creation of a parser context with |
| 124 | createFileParserCtxt() and how the behaviour can be changed before calling |
William M. Brack | 43a8729 | 2007-02-15 20:41:02 +0000 | [diff] [blame] | 125 | parseDocument() . Similarly the information resulting from the parsing phase |
| 126 | is also available using context methods.</p><p>Contexts like nodes are defined as class and the libxml2 wrappers maps the |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 127 | C function interfaces in terms of objects method as much as possible. The |
| 128 | best to get a complete view of what methods are supported is to look at the |
| 129 | libxml2.py module containing all the wrappers.</p><h3>push.py:</h3><p>This test show how to activate the push parser interface:</p><pre>import libxml2 |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 130 | |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 131 | ctxt = libxml2.createPushParser(None, "<foo", 4, "test.xml") |
| 132 | ctxt.parseChunk("/>", 2, 1) |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 133 | doc = ctxt.doc() |
| 134 | |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 135 | doc.freeDoc()</pre><p>The context is created with a special call based on the |
| 136 | xmlCreatePushParser() from the C library. The first argument is an optional |
| 137 | SAX callback object, then the initial set of data, the length and the name of |
| 138 | the resource in case URI-References need to be computed by the parser.</p><p>Then the data are pushed using the parseChunk() method, the last call |
| 139 | setting the third argument terminate to 1.</p><h3>pushSAX.py:</h3><p>this test show the use of the event based parsing interfaces. In this case |
| 140 | the parser does not build a document, but provides callback information as |
| 141 | the parser makes progresses analyzing the data being provided:</p><pre>import libxml2 |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 142 | log = "" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 143 | |
| 144 | class callback: |
| 145 | def startDocument(self): |
| 146 | global log |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 147 | log = log + "startDocument:" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 148 | |
| 149 | def endDocument(self): |
| 150 | global log |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 151 | log = log + "endDocument:" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 152 | |
| 153 | def startElement(self, tag, attrs): |
| 154 | global log |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 155 | log = log + "startElement %s %s:" % (tag, attrs) |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 156 | |
| 157 | def endElement(self, tag): |
| 158 | global log |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 159 | log = log + "endElement %s:" % (tag) |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 160 | |
| 161 | def characters(self, data): |
| 162 | global log |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 163 | log = log + "characters: %s:" % (data) |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 164 | |
| 165 | def warning(self, msg): |
| 166 | global log |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 167 | log = log + "warning: %s:" % (msg) |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 168 | |
| 169 | def error(self, msg): |
| 170 | global log |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 171 | log = log + "error: %s:" % (msg) |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 172 | |
| 173 | def fatalError(self, msg): |
| 174 | global log |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 175 | log = log + "fatalError: %s:" % (msg) |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 176 | |
| 177 | handler = callback() |
| 178 | |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 179 | ctxt = libxml2.createPushParser(handler, "<foo", 4, "test.xml") |
| 180 | chunk = " url='tst'>b" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 181 | ctxt.parseChunk(chunk, len(chunk), 0) |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 182 | chunk = "ar</foo>" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 183 | ctxt.parseChunk(chunk, len(chunk), 1) |
| 184 | |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 185 | reference = "startDocument:startElement foo {'url': 'tst'}:" + \ |
| 186 | "characters: bar:endElement foo:endDocument:" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 187 | if log != reference: |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 188 | print "Error got: %s" % log |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 189 | print "Expected: %s" % reference</pre><p>The key object in that test is the handler, it provides a number of entry |
| 190 | points which can be called by the parser as it makes progresses to indicate |
| 191 | the information set obtained. The full set of callback is larger than what |
| 192 | the callback class in that specific example implements (see the SAX |
| 193 | definition for a complete list). The wrapper will only call those supplied by |
| 194 | the object when activated. The startElement receives the names of the element |
| 195 | and a dictionary containing the attributes carried by this element.</p><p>Also note that the reference string generated from the callback shows a |
| 196 | single character call even though the string "bar" is passed to the parser |
| 197 | from 2 different call to parseChunk()</p><h3>xpath.py:</h3><p>This is a basic test of XPath wrappers support</p><pre>import libxml2 |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 198 | |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 199 | doc = libxml2.parseFile("tst.xml") |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 200 | ctxt = doc.xpathNewContext() |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 201 | res = ctxt.xpathEval("//*") |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 202 | if len(res) != 2: |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 203 | print "xpath query: wrong node set size" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 204 | sys.exit(1) |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 205 | if res[0].name != "doc" or res[1].name != "foo": |
| 206 | print "xpath query: wrong node set value" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 207 | sys.exit(1) |
| 208 | doc.freeDoc() |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 209 | ctxt.xpathFreeContext()</pre><p>This test parses a file, then create an XPath context to evaluate XPath |
| 210 | expression on it. The xpathEval() method execute an XPath query and returns |
| 211 | the result mapped in a Python way. String and numbers are natively converted, |
| 212 | and node sets are returned as a tuple of libxml2 Python nodes wrappers. Like |
| 213 | the document, the XPath context need to be freed explicitly, also not that |
| 214 | the result of the XPath query may point back to the document tree and hence |
| 215 | the document must be freed after the result of the query is used.</p><h3>xpathext.py:</h3><p>This test shows how to extend the XPath engine with functions written in |
| 216 | python:</p><pre>import libxml2 |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 217 | |
| 218 | def foo(ctx, x): |
| 219 | return x + 1 |
| 220 | |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 221 | doc = libxml2.parseFile("tst.xml") |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 222 | ctxt = doc.xpathNewContext() |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 223 | libxml2.registerXPathFunction(ctxt._o, "foo", None, foo) |
| 224 | res = ctxt.xpathEval("foo(1)") |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 225 | if res != 2: |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 226 | print "xpath extension failure" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 227 | doc.freeDoc() |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 228 | ctxt.xpathFreeContext()</pre><p>Note how the extension function is registered with the context (but that |
| 229 | part is not yet finalized, this may change slightly in the future).</p><h3>tstxpath.py:</h3><p>This test is similar to the previous one but shows how the extension |
| 230 | function can access the XPath evaluation context:</p><pre>def foo(ctx, x): |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 231 | global called |
| 232 | |
| 233 | # |
| 234 | # test that access to the XPath evaluation contexts |
| 235 | # |
| 236 | pctxt = libxml2.xpathParserContext(_obj=ctx) |
| 237 | ctxt = pctxt.context() |
| 238 | called = ctxt.function() |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 239 | return x + 1</pre><p>All the interfaces around the XPath parser(or rather evaluation) context |
| 240 | are not finalized, but it should be sufficient to do contextual work at the |
| 241 | evaluation point.</p><h3>Memory debugging:</h3><p>last but not least, all tests starts with the following prologue:</p><pre>#memory debug specific |
Daniel Veillard | 1177ca4 | 2003-04-26 22:29:54 +0000 | [diff] [blame] | 242 | libxml2.debugMemory(1)</pre><p>and ends with the following epilogue:</p><pre>#memory debug specific |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 243 | libxml2.cleanupParser() |
| 244 | if libxml2.debugMemory(1) == 0: |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 245 | print "OK" |
Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 246 | else: |
Daniel Veillard | 024f199 | 2003-12-10 16:43:49 +0000 | [diff] [blame] | 247 | print "Memory leak %d bytes" % (libxml2.debugMemory(1)) |
Daniel Veillard | f781dba | 2006-06-09 13:34:49 +0000 | [diff] [blame] | 248 | libxml2.dumpMemory()</pre><p>Those activate the memory debugging interface of libxml2 where all |
| 249 | allocated block in the library are tracked. The prologue then cleans up the |
| 250 | library state and checks that all allocated memory has been freed. If not it |
| 251 | calls dumpMemory() which saves that list in a <code>.memdump</code> file.</p><p><a href="bugs.html">Daniel Veillard</a></p></td></tr></table></td></tr></table></td></tr></table></td></tr></table></td></tr></table></body></html> |