Class: Nokogiri::XML::Reader
Relationships & Source Files | |
Super Chains via Extension / Inclusion / Inheritance | |
Instance Chain:
self,
Enumerable
|
|
Inherits: | Object |
Defined in: | lib/nokogiri/xml/reader.rb, ext/nokogiri/xml_node.c, ext/nokogiri/xml_reader.c |
Overview
Reader
parses an ::Nokogiri::XML
document similar to the way a cursor would move. The Reader
is given an ::Nokogiri::XML
document, and yields nodes to an each block.
The Reader parser might be good for when you need the speed and low memory usage of the SAX
parser, but do not want to write a Document
handler.
Here is an example of usage:
reader = Nokogiri::XML::Reader(<<-eoxml)
<x xmlns:tenderlove='http://tenderlovemaking.com/'>
<tenderlove:foo awesome='true'>snuggles!</tenderlove:foo>
</x>
eoxml
reader.each do |node|
# node is an instance of Nokogiri::XML::Reader
puts node.name
end
⚠ #each can only be called once! Once the cursor moves through the entire document, you must parse the document again. It may be better to capture all information you need during a single iteration.
⚠ libxml2 does not support error recovery in the Reader
parser. The RECOVER
ParseOption is ignored. If a syntax error is encountered during parsing, an exception will be raised.
Constant Summary
-
TYPE_ATTRIBUTE =
Attribute node type
2
-
TYPE_CDATA =
CDATA
node type4
-
TYPE_COMMENT =
Comment
node type8
-
TYPE_DOCUMENT =
Document
node type9
-
TYPE_DOCUMENT_FRAGMENT =
Document
Fragment node type11
-
TYPE_DOCUMENT_TYPE =
Document
Type node type10
-
TYPE_ELEMENT =
Element
node type1
-
TYPE_END_ELEMENT =
Element
end node type15
-
TYPE_END_ENTITY =
Entity end node type
16
-
TYPE_ENTITY =
Entity node type
6
-
TYPE_ENTITY_REFERENCE =
Entity Reference node type
5
-
TYPE_NONE =
# File 'lib/nokogiri/xml/reader.rb', line 360
-
TYPE_NOTATION =
Notation
node type12
-
TYPE_PROCESSING_INSTRUCTION =
PI node type
7
-
TYPE_SIGNIFICANT_WHITESPACE =
Significant Whitespace node type
14
-
TYPE_TEXT =
Text
node type3
-
TYPE_WHITESPACE =
Whitespace node type
13
-
TYPE_XML_DECLARATION =
::Nokogiri::XML
Declaration node type17
Class Method Summary
-
.from_io(io, url = nil, encoding = nil, options = 0)
Create a new reader that parses
io
-
.from_memory(string, url = nil, encoding = nil, options = 0)
Create a new reader that parses
string
- .new(source, url = nil, encoding = nil) ⇒ Reader constructor Internal use only
Instance Attribute Summary
-
#attributes? ⇒ Boolean
readonly
Does this node have attributes?
-
#default? ⇒ Boolean
readonly
Was an attribute generated from the default value in the
DTD
or schema? -
#empty_element?(#) ⇒ Boolean
(also: #self_closing?)
readonly
Returns true if the current node is empty, otherwise false.
-
#errors
rw
A list of errors encountered while parsing.
-
#self_closing?
readonly
Alias for #empty_element?.
-
#source
readonly
The XML source.
-
#value
readonly
Get the text value of the node if present.
-
#value? ⇒ Boolean
readonly
Does this node have a text value?
Instance Method Summary
-
#attribute(name)
Get the value of attribute named #name
-
#attribute_at(index)
Get the value of attribute at
index
-
#attribute_count
Get the number of attributes for the current node.
-
#attribute_hash() → Hash<String ⇒ String>)
Get the attributes of the current node as a Hash of names and values.
-
#attributes
readonly
Get the attributes and namespaces of the current node as a Hash.
-
#base_uri
Get the xml:base of the node.
-
#depth
Get the depth of the node.
-
#each
Move the cursor through the document yielding the cursor to the block.
- #encoding
-
#inner_xml
Read the contents of the current node, including child nodes and markup.
-
#lang
Get the xml:lang scope within which the node resides.
-
#local_name
Get the local name of the node.
-
#name
Get the name of the node.
-
#namespace_uri
Get the URI defining the namespace associated with the node.
-
#namespaces
Get a hash of namespaces for this
Node
. -
#node_type
Alias for Node#node_type.
-
#outer_xml
Read the current node and its contents, including child nodes and markup.
-
#prefix
Get the shorthand reference to the namespace associated with the node.
-
#read
Move the
Reader
forward through the::Nokogiri::XML
document. -
#state
Get the state of the reader.
-
#xml_version
Get the
::Nokogiri::XML
version of the document being read.
Constructor Details
.new(source, url = nil, encoding = nil) ⇒ Reader
Class Method Details
.from_io(io, url = nil, encoding = nil, options = 0)
Create a new reader that parses io
# File 'ext/nokogiri/xml_reader.c', line 658
static VALUE from_io(int argc, VALUE *argv, VALUE klass) { VALUE rb_io, rb_url, encoding, rb_options; xmlTextReaderPtr reader; const char *c_url = NULL; const char *c_encoding = NULL; int c_options = 0; VALUE rb_reader, args[3]; rb_scan_args(argc, argv, "13", &rb_io, &rb_url, &encoding, &rb_options); if (!RTEST(rb_io)) { rb_raise(rb_eArgError, "io cannot be nil"); } if (RTEST(rb_url)) { c_url = StringValueCStr(rb_url); } if (RTEST(encoding)) { c_encoding = StringValueCStr(encoding); } if (RTEST(rb_options)) { c_options = (int)NUM2INT(rb_options); } reader = xmlReaderForIO( (xmlInputReadCallback)noko_io_read, (xmlInputCloseCallback)noko_io_close, (void *)rb_io, c_url, c_encoding, c_options ); if (reader == NULL) { xmlFreeTextReader(reader); rb_raise(rb_eRuntimeError, "couldn't create a parser"); } rb_reader = TypedData_Wrap_Struct(klass, &xml_text_reader_type, reader); args[0] = rb_io; args[1] = rb_url; args[2] = encoding; rb_obj_call_init(rb_reader, 3, args); return rb_reader; }
.from_memory(string, url = nil, encoding = nil, options = 0)
Create a new reader that parses string
# File 'ext/nokogiri/xml_reader.c', line 613
static VALUE from_memory(int argc, VALUE *argv, VALUE klass) { VALUE rb_buffer, rb_url, encoding, rb_options; xmlTextReaderPtr reader; const char *c_url = NULL; const char *c_encoding = NULL; int c_options = 0; VALUE rb_reader, args[3]; rb_scan_args(argc, argv, "13", &rb_buffer, &rb_url, &encoding, &rb_options); if (!RTEST(rb_buffer)) { rb_raise(rb_eArgError, "string cannot be nil"); } if (RTEST(rb_url)) { c_url = StringValueCStr(rb_url); } if (RTEST(encoding)) { c_encoding = StringValueCStr(encoding); } if (RTEST(rb_options)) { c_options = (int)NUM2INT(rb_options); } reader = xmlReaderForMemory( StringValuePtr(rb_buffer), (int)RSTRING_LEN(rb_buffer), c_url, c_encoding, c_options ); if (reader == NULL) { xmlFreeTextReader(reader); rb_raise(rb_eRuntimeError, "couldn't create a parser"); } rb_reader = TypedData_Wrap_Struct(klass, &xml_text_reader_type, reader); args[0] = rb_buffer; args[1] = rb_url; args[2] = encoding; rb_obj_call_init(rb_reader, 3, args); return rb_reader; }
Instance Attribute Details
#attributes? ⇒ Boolean
(readonly)
Does this node have attributes?
# File 'ext/nokogiri/xml_reader.c', line 121
static VALUE attributes_eh(VALUE self) { xmlTextReaderPtr reader; int eh; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); eh = has_attributes(reader); if (eh == 0) { return Qfalse; } if (eh == 1) { return Qtrue; } return Qnil; }
#default? ⇒ Boolean
(readonly)
Was an attribute generated from the default value in the DTD
or schema?
# File 'ext/nokogiri/xml_reader.c', line 81
static VALUE default_eh(VALUE self) { xmlTextReaderPtr reader; int eh; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); eh = xmlTextReaderIsDefault(reader); if (eh == 0) { return Qfalse; } if (eh == 1) { return Qtrue; } return Qnil; }
#empty_element?(#) ⇒ Boolean
(readonly) Also known as: #self_closing?
Returns true if the current node is empty, otherwise false.
# File 'ext/nokogiri/xml_reader.c', line 704
static VALUE empty_element_p(VALUE self) { xmlTextReaderPtr reader; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); if (xmlTextReaderIsEmptyElement(reader)) { return Qtrue; } return Qfalse; }
#errors (rw)
A list of errors encountered while parsing
# File 'lib/nokogiri/xml/reader.rb', line 73
attr_accessor :errors
#self_closing? (readonly)
Alias for #empty_element?.
# File 'lib/nokogiri/xml/reader.rb', line 78
alias_method :self_closing?, :empty_element?
#source (readonly)
The XML source
# File 'lib/nokogiri/xml/reader.rb', line 76
attr_reader :source
#value (readonly)
Get the text value of the node if present. Returns a utf-8 encoded string.
# File 'ext/nokogiri/xml_reader.c', line 368
static VALUE value(VALUE self) { xmlTextReaderPtr reader; const char *value; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); value = (const char *)xmlTextReaderConstValue(reader); if (value == NULL) { return Qnil; } return NOKOGIRI_STR_NEW2(value); }
#value? ⇒ Boolean
(readonly)
Does this node have a text value?
# File 'ext/nokogiri/xml_reader.c', line 101
static VALUE value_eh(VALUE self) { xmlTextReaderPtr reader; int eh; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); eh = xmlTextReaderHasValue(reader); if (eh == 0) { return Qfalse; } if (eh == 1) { return Qtrue; } return Qnil; }
Instance Method Details
#attribute(name)
Get the value of attribute named #name
# File 'ext/nokogiri/xml_reader.c', line 266
static VALUE reader_attribute(VALUE self, VALUE name) { xmlTextReaderPtr reader; xmlChar *value ; VALUE rb_value; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); if (NIL_P(name)) { return Qnil; } name = StringValue(name) ; value = xmlTextReaderGetAttribute(reader, (xmlChar *)StringValueCStr(name)); if (value == NULL) { return Qnil; } rb_value = NOKOGIRI_STR_NEW2(value); xmlFree(value); return rb_value; }
#attribute_at(index)
Get the value of attribute at index
# File 'ext/nokogiri/xml_reader.c', line 237
static VALUE attribute_at(VALUE self, VALUE index) { xmlTextReaderPtr reader; xmlChar *value; VALUE rb_value; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); if (NIL_P(index)) { return Qnil; } index = rb_Integer(index); value = xmlTextReaderGetAttributeNo( reader, (int)NUM2INT(index) ); if (value == NULL) { return Qnil; } rb_value = NOKOGIRI_STR_NEW2(value); xmlFree(value); return rb_value; }
#attribute_count
Get the number of attributes for the current node
# File 'ext/nokogiri/xml_reader.c', line 292
static VALUE attribute_count(VALUE self) { xmlTextReaderPtr reader; int count; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); count = xmlTextReaderAttributeCount(reader); if (count == -1) { return Qnil; } return INT2NUM(count); }
#attribute_hash() → Hash<String ⇒ String>)
Get the attributes of the current node as a Hash of names and values.
See related: #attributes and #namespaces
# File 'ext/nokogiri/xml_reader.c', line 182
static VALUE rb_xml_reader_attribute_hash(VALUE rb_reader) { VALUE rb_attributes = rb_hash_new(); xmlTextReaderPtr c_reader; xmlNodePtr c_node; xmlAttrPtr c_property; VALUE rb_errors; TypedData_Get_Struct(rb_reader, xmlTextReader, &xml_text_reader_type, c_reader); if (!has_attributes(c_reader)) { return rb_attributes; } rb_errors = rb_funcall(rb_reader, rb_intern("errors"), 0); xmlSetStructuredErrorFunc((void *)rb_errors, noko__error_array_pusher); c_node = xmlTextReaderExpand(c_reader); xmlSetStructuredErrorFunc(NULL, NULL); if (c_node == NULL) { if (RARRAY_LEN(rb_errors) > 0) { VALUE rb_error = rb_ary_entry(rb_errors, 0); VALUE exception_message = rb_funcall(rb_error, rb_intern("to_s"), 0); rb_exc_raise(rb_class_new_instance(1, &exception_message, cNokogiriXmlSyntaxError)); } return Qnil; } c_property = c_node->properties; while (c_property != NULL) { VALUE rb_name = NOKOGIRI_STR_NEW2(c_property->name); VALUE rb_value = Qnil; xmlChar *c_value = xmlNodeGetContent((xmlNode *)c_property); if (c_value) { rb_value = NOKOGIRI_STR_NEW2(c_value); xmlFree(c_value); } rb_hash_aset(rb_attributes, rb_name, rb_value); c_property = c_property->next; } return rb_attributes; }
#attributes (readonly)
Get the attributes and namespaces of the current node as a Hash.
This is the union of #attribute_hash and #namespaces
- Returns
-
(Hash<String, String>) Attribute names and values, and namespace prefixes and hrefs.
# File 'lib/nokogiri/xml/reader.rb', line 93
def attributes attribute_hash.merge(namespaces) end
#base_uri
Get the xml:base of the node
# File 'ext/nokogiri/xml_reader.c', line 463
static VALUE rb_xml_reader_base_uri(VALUE rb_reader) { VALUE rb_base_uri; xmlTextReaderPtr c_reader; xmlChar *c_base_uri; TypedData_Get_Struct(rb_reader, xmlTextReader, &xml_text_reader_type, c_reader); c_base_uri = xmlTextReaderBaseUri(c_reader); if (c_base_uri == NULL) { return Qnil; } rb_base_uri = NOKOGIRI_STR_NEW2(c_base_uri); xmlFree(c_base_uri); return rb_base_uri; }
#depth
Get the depth of the node
# File 'ext/nokogiri/xml_reader.c', line 311
static VALUE depth(VALUE self) { xmlTextReaderPtr reader; int depth; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); depth = xmlTextReaderDepth(reader); if (depth == -1) { return Qnil; } return INT2NUM(depth); }
#each
Move the cursor through the document yielding the cursor to the block
# File 'lib/nokogiri/xml/reader.rb', line 99
def each while (cursor = read) yield cursor end end
#encoding
[ GitHub ]# File 'ext/nokogiri/xml_reader.c', line 718
static VALUE rb_xml_reader_encoding(VALUE rb_reader) { xmlTextReaderPtr c_reader; const char *parser_encoding; VALUE constructor_encoding; TypedData_Get_Struct(rb_reader, xmlTextReader, &xml_text_reader_type, c_reader); parser_encoding = (const char *)xmlTextReaderConstEncoding(c_reader); if (parser_encoding) { return NOKOGIRI_STR_NEW2(parser_encoding); } constructor_encoding = rb_iv_get(rb_reader, "@encoding"); if (RTEST(constructor_encoding)) { return constructor_encoding; } return Qnil; }
#inner_xml
Read the contents of the current node, including child nodes and markup. Returns a utf-8 encoded string.
# File 'ext/nokogiri/xml_reader.c', line 562
static VALUE inner_xml(VALUE self) { xmlTextReaderPtr reader; xmlChar *value; VALUE str; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); value = xmlTextReaderReadInnerXml(reader); str = Qnil; if (value) { str = NOKOGIRI_STR_NEW2((char *)value); xmlFree(value); } return str; }
#lang
Get the xml:lang scope within which the node resides.
# File 'ext/nokogiri/xml_reader.c', line 349
static VALUE lang(VALUE self) { xmlTextReaderPtr reader; const char *lang; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); lang = (const char *)xmlTextReaderConstXmlLang(reader); if (lang == NULL) { return Qnil; } return NOKOGIRI_STR_NEW2(lang); }
#local_name
Get the local name of the node
# File 'ext/nokogiri/xml_reader.c', line 425
static VALUE local_name(VALUE self) { xmlTextReaderPtr reader; const char *name; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); name = (const char *)xmlTextReaderConstLocalName(reader); if (name == NULL) { return Qnil; } return NOKOGIRI_STR_NEW2(name); }
#name
Get the name of the node. Returns a utf-8 encoded string.
# File 'ext/nokogiri/xml_reader.c', line 444
static VALUE name(VALUE self) { xmlTextReaderPtr reader; const char *name; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); name = (const char *)xmlTextReaderConstName(reader); if (name == NULL) { return Qnil; } return NOKOGIRI_STR_NEW2(name); }
#namespace_uri
Get the URI defining the namespace associated with the node
# File 'ext/nokogiri/xml_reader.c', line 406
static VALUE namespace_uri(VALUE self) { xmlTextReaderPtr reader; const char *uri; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); uri = (const char *)xmlTextReaderConstNamespaceUri(reader); if (uri == NULL) { return Qnil; } return NOKOGIRI_STR_NEW2(uri); }
#namespaces
Get a hash of namespaces for this Node
# File 'ext/nokogiri/xml_reader.c', line 141
static VALUE rb_xml_reader_namespaces(VALUE rb_reader) { VALUE rb_namespaces = rb_hash_new() ; xmlTextReaderPtr c_reader; xmlNodePtr c_node; VALUE rb_errors; TypedData_Get_Struct(rb_reader, xmlTextReader, &xml_text_reader_type, c_reader); if (! has_attributes(c_reader)) { return rb_namespaces ; } rb_errors = rb_funcall(rb_reader, rb_intern("errors"), 0); xmlSetStructuredErrorFunc((void *)rb_errors, noko__error_array_pusher); c_node = xmlTextReaderExpand(c_reader); xmlSetStructuredErrorFunc(NULL, NULL); if (c_node == NULL) { if (RARRAY_LEN(rb_errors) > 0) { VALUE rb_error = rb_ary_entry(rb_errors, 0); VALUE exception_message = rb_funcall(rb_error, rb_intern("to_s"), 0); rb_exc_raise(rb_class_new_instance(1, &exception_message, cNokogiriXmlSyntaxError)); } return Qnil; } Nokogiri_xml_node_namespaces(c_node, rb_namespaces); return rb_namespaces ; }
#node_type
Alias for Node#node_type.
#outer_xml
Read the current node and its contents, including child nodes and markup. Returns a utf-8 encoded string.
# File 'ext/nokogiri/xml_reader.c', line 589
static VALUE outer_xml(VALUE self) { xmlTextReaderPtr reader; xmlChar *value; VALUE str = Qnil; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); value = xmlTextReaderReadOuterXml(reader); if (value) { str = NOKOGIRI_STR_NEW2((char *)value); xmlFree(value); } return str; }
#prefix
Get the shorthand reference to the namespace associated with the node.
# File 'ext/nokogiri/xml_reader.c', line 387
static VALUE prefix(VALUE self) { xmlTextReaderPtr reader; const char *prefix; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); prefix = (const char *)xmlTextReaderConstPrefix(reader); if (prefix == NULL) { return Qnil; } return NOKOGIRI_STR_NEW2(prefix); }
#read
Move the Reader
forward through the ::Nokogiri::XML
document.
# File 'ext/nokogiri/xml_reader.c', line 517
static VALUE read_more(VALUE rb_reader) { xmlTextReaderPtr c_reader; libxmlStructuredErrorHandlerState handler_state; TypedData_Get_Struct(rb_reader, xmlTextReader, &xml_text_reader_type, c_reader); VALUE rb_errors = rb_funcall(rb_reader, rb_intern("errors"), 0); noko__structured_error_func_save_and_set(&handler_state, (void *)rb_errors, noko__error_array_pusher); int status = xmlTextReaderRead(c_reader); noko__structured_error_func_restore(&handler_state); xmlDocPtr c_document = xmlTextReaderCurrentDoc(c_reader); if (c_document && c_document->encoding == NULL) { VALUE constructor_encoding = rb_iv_get(rb_reader, "@encoding"); if (RTEST(constructor_encoding)) { c_document->encoding = xmlStrdup(BAD_CAST StringValueCStr(constructor_encoding)); } else { rb_iv_set(rb_reader, "@encoding", NOKOGIRI_STR_NEW2("UTF-8")); c_document->encoding = xmlStrdup(BAD_CAST "UTF-8"); } } if (status == 1) { return rb_reader; } if (status == 0) { return Qnil; } /* if we're here, there was an error */ VALUE exception = rb_funcall(cNokogiriXmlSyntaxError, rb_intern("aggregate"), 1, rb_errors); if (RB_TEST(exception)) { rb_exc_raise(exception); } else { rb_raise(rb_eRuntimeError, "Error pulling: %d", status); } }
#state
Get the state of the reader
# File 'ext/nokogiri/xml_reader.c', line 489
static VALUE state(VALUE self) { xmlTextReaderPtr reader; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); return INT2NUM(xmlTextReaderReadState(reader)); }
#xml_version
Get the ::Nokogiri::XML
version of the document being read
# File 'ext/nokogiri/xml_reader.c', line 330
static VALUE xml_version(VALUE self) { xmlTextReaderPtr reader; const char *version; TypedData_Get_Struct(self, xmlTextReader, &xml_text_reader_type, reader); version = (const char *)xmlTextReaderConstXmlVersion(reader); if (version == NULL) { return Qnil; } return NOKOGIRI_STR_NEW2(version); }