EzXML.jl - XML/HTML tools for primates

EzXML.jl is a package to handle XML/HTML documents for primates.

The main features are:

• Reading and writing XML/HTML documents.
• Traversing XML/HTML trees with DOM interfaces.
• Searching elements using XPath.
• Proper namespace handling.
• Capturing error messages.
• Automatic memory management.
• Document validation.
• Streaming parsing for large XML files.

Installation

Install EzXML.jl as follows:

julia -e 'using Pkg; Pkg.add("EzXML")'

This package depends on libxml2, which will be automatically installed as an artifact via XML2_jll.jl if you use Julia 1.3 or later. Currently, Windows, Linux, macOS, and FreeBSD are now supported.

Version compatibility

EzXML.jl	Julia
1.0	1.0 or later
1.1	1.3 or later

Usage

# Load the package.
using EzXML

# Parse an XML string
# (use `readxml(<filename>)` to read a document from a file).
doc = parsexml("""
<primates>
    <genus name="Homo">
        <species name="sapiens">Human</species>
    </genus>
    <genus name="Pan">
        <species name="paniscus">Bonobo</species>
        <species name="troglodytes">Chimpanzee</species>
    </genus>
</primates>
""")

# Get the root element from `doc`.
primates = root(doc)  # or `doc.root`

# Iterate over child elements.
for genus in eachelement(primates)
    # Get an attribute value by name.
    genus_name = genus["name"]
    println("- ", genus_name)
    for species in eachelement(genus)
        # Get the content within an element.
        species_name = nodecontent(species)  # or `species.content`
        println("  └ ", species["name"], " (", species_name, ")")
    end
end
println()

# Find texts using XPath query.
for species_name in nodecontent.(findall("//species/text()", primates))
    println("- ", species_name)
end

Quick reference

See the reference page or docstrings for more details.

Types:

• EzXML.Document: an XML/HTML document
• EzXML.Node: an XML/HTML node including elements, attributes, texts, etc.
• EzXML.XMLError: an error happened in libxml2
• EzXML.StreamReader: a streaming XML reader

IO:

• From file: readxml(filename|stream), readhtml(filename|stream)
• From string or byte array: parsexml(string), parsehtml(string)
• To file: write(filename, doc)
• To stream: print(io, doc)

Accessors:

• Node information: nodetype(node), nodepath(node), nodename(node), nodecontent(node), setnodename!(node, name), setnodecontent!(node, content)
• Node property: node.type, node.name, node.path, node.content, node.namespace
• Document:
  • Property: version(doc), encoding(doc), hasversion(doc), hasencoding(doc)
  • Node: root(doc), dtd(doc), hasroot(doc), hasdtd(doc), setroot!(doc, element_node), setdtd!(doc, dtd_node)
• Document property: doc.version, doc.encoding, doc.node, doc.root, doc.dtd
• Attributes: node[name], node[name] = value, haskey(node, name), delete!(node, name)
• Node predicate:
  • Document: hasdocument(node)
  • Parent: hasparentnode(node), hasparentelement(node)
  • Child: hasnode(node), haselement(node)
  • Sibling: hasnextnode(node), hasprevnode(node), hasnextelement(node), hasprevelement(node)
  • Node type: iselement(node), isattribute(node), istext(node), iscdata(node), iscomment(node), isdtd(node)
• Tree traversal:
  • Document: document(node)
  • Parent: parentnode(node), parentelement(node)
  • Child: firstnode(node), lastnode(node), firstelement(node), lastelement(node)
  • Sibling: nextnode(node), prevnode(node), nextelement(node), prevelement(node)
• Tree modifiers:
  • Link: link!(parent_node, child_node), linknext!(target_node, node), linkprev!(target_node, node)
  • Unlink: unlink!(node)
  • Create: addelement!(parent_node, name, [content])
• Iterators:
  • Iterator: eachnode(node), eachelement(node), eachattribute(node)
  • Vector: nodes(node), elements(node), attributes(node)
• Counters: countnodes(node), countelements(node), countattributes(node)
• Namespaces: namespace(node), namespaces(node)

Constructors:

• EzXML.Document type: XMLDocument(version="1.0"), HTMLDocument(uri=nothing, externalID=nothing)
• EzXML.Node type: XMLDocumentNode(version="1.0"), HTMLDocumentNode(uri, externalID), ElementNode(name), TextNode(content), CommentNode(content), CDataNode(content), AttributeNode(name, value), DTDNode(name, [systemID, [externalID]])

Queries:

• XPath: findall(xpath, doc|node), findfirst(xpath, doc|node), findlast(xpath, doc|node)
  (Note the caveat on the combination of XPath and namespaces in the manual)

Examples

• primates.jl: Run "primates" example shown above.
• julia2xml.jl: Convert a Julia expression to XML.
• listlinks.jl: List all links in an HTML document.

Other XML/HTML packages in Julia

• LightXML.jl
• LibExpat.jl