autofill_xml_parser.h revision eb525c5499e34cc9c4b825d6d9e75bb07cc06ace 
1// Copyright 2013 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef COMPONENTS_AUTOFILL_CORE_BROWSER_AUTOFILL_XML_PARSER_H_
6#define COMPONENTS_AUTOFILL_CORE_BROWSER_AUTOFILL_XML_PARSER_H_
7
8#include <string>
9#include <vector>
10
11#include "base/basictypes.h"
12#include "base/compiler_specific.h"
13#include "base/memory/scoped_ptr.h"
14#include "components/autofill/core/browser/autofill_server_field_info.h"
15#include "components/autofill/core/browser/field_types.h"
16#include "components/autofill/core/browser/form_structure.h"
17#include "third_party/libjingle/source/talk/xmllite/xmlparser.h"
18
19namespace autofill {
20
21struct AutocheckoutPageMetaData;
22
23// The base class that contains common functionality between
24// AutofillQueryXmlParser and AutofillUploadXmlParser.
25class AutofillXmlParser : public buzz::XmlParseHandler {
26 public:
27  AutofillXmlParser();
28  virtual ~AutofillXmlParser();
29
30  // Returns true if no parsing errors were encountered.
31  bool succeeded() const { return succeeded_; }
32
33 private:
34  // A callback for the end of an </element>, called by Expat.
35  // |context| is a parsing context used to resolve element/attribute names.
36  // |name| is the name of the element.
37  virtual void EndElement(buzz::XmlParseContext* context,
38                          const char* name) OVERRIDE;
39
40  // The callback for character data between tags (<element>text...</element>).
41  // |context| is a parsing context used to resolve element/attribute names.
42  // |text| is a pointer to the beginning of character data (not null
43  // terminated).
44  // |len| is the length of the string pointed to by text.
45  virtual void CharacterData(buzz::XmlParseContext* context,
46                             const char* text,
47                             int len) OVERRIDE;
48
49  // The callback for parsing errors.
50  // |context| is a parsing context used to resolve names.
51  // |error_code| is a code representing the parsing error.
52  virtual void Error(buzz::XmlParseContext* context,
53                     XML_Error error_code) OVERRIDE;
54
55  // True if parsing succeeded.
56  bool succeeded_;
57
58  DISALLOW_COPY_AND_ASSIGN(AutofillXmlParser);
59};
60
61// The XML parse handler for parsing Autofill query responses.  A typical
62// response looks like:
63//
64// <autofillqueryresponse experimentid="1">
65//   <field autofilltype="0" />
66//   <field autofilltype="1" />
67//   <field autofilltype="3" />
68//   <field autofilltype="2" />
69// </autofillqueryresponse>
70//
71// Fields are returned in the same order they were sent to the server.
72// autofilltype: The server's guess at what type of field this is.  0
73// is unknown, other types are documented in
74// components/autofill/core/browser/field_types.h.
75class AutofillQueryXmlParser : public AutofillXmlParser {
76 public:
77  AutofillQueryXmlParser(std::vector<AutofillServerFieldInfo>* field_infos,
78                         UploadRequired* upload_required,
79                         std::string* experiment_id,
80                         AutocheckoutPageMetaData* page_meta_data);
81  virtual ~AutofillQueryXmlParser();
82
83 private:
84  // A callback for the beginning of a new <element>, called by Expat.
85  // |context| is a parsing context used to resolve element/attribute names.
86  // |name| is the name of the element.
87  // |attrs| is the list of attributes (names and values) for the element.
88  virtual void StartElement(buzz::XmlParseContext* context,
89                            const char* name,
90                            const char** attrs) OVERRIDE;
91
92  // A helper function to parse a |WebElementDescriptor|.
93  // |context| is the current parsing context.
94  // |attrs| is the list of attributes (names and values) for the element.
95  // |element_descriptor| will be populated by this function.
96  void ParseElementDescriptor(buzz::XmlParseContext* context,
97                              const char* const* attrs,
98                              WebElementDescriptor* element_descriptor);
99
100  // A callback for the end of an </element>, called by Expat.
101  // |context| is a parsing context used to resolve element/attribute names.
102  // |name| is the name of the element.
103  virtual void EndElement(buzz::XmlParseContext* context,
104                          const char* name) OVERRIDE;
105
106  // The callback for character data between tags (<element>text...</element>).
107  // |context| is a parsing context used to resolve element/attribute names.
108  // |text| is a pointer to the beginning of character data (not null
109  // terminated).
110  // |len| is the length of the string pointed to by text.
111  virtual void CharacterData(buzz::XmlParseContext* context,
112                             const char* text,
113                             int len) OVERRIDE;
114
115  // A helper function to retrieve integer values from strings.  Raises an
116  // XML parse error if it fails.
117  // |context| is the current parsing context.
118  // |value| is the string to convert.
119  int GetIntValue(buzz::XmlParseContext* context, const char* attribute);
120
121  // The parsed <field type, default value> pairs.
122  std::vector<AutofillServerFieldInfo>* field_infos_;
123
124  // A flag indicating whether the client should upload Autofill data when this
125  // form is submitted.
126  UploadRequired* upload_required_;
127
128  // The server experiment to which this query response belongs.
129  // For the default server implementation, this is empty.
130  std::string* experiment_id_;
131
132  // Page metadata for multipage autofill flow.
133  AutocheckoutPageMetaData* page_meta_data_;
134
135  // The click element the parser is currently processing.
136  WebElementDescriptor* current_click_element_;
137
138  // Number of page whose type is currently being parsed.
139  int current_page_number_for_page_types_;
140
141  // Whether the instance is currently parsing inside 'type' tags.
142  bool is_in_type_section_;
143
144  DISALLOW_COPY_AND_ASSIGN(AutofillQueryXmlParser);
145};
146
147// The XML parser for handling Autofill upload responses.  Typical upload
148// responses look like:
149//
150// <autofilluploadresponse negativeuploadrate="0.00125" positiveuploadrate="1"/>
151//
152// The positive upload rate is the percentage of uploads to send to the server
153// when something in the users profile matches what they have entered in a form.
154// The negative upload rate is the percentage of uploads to send when nothing in
155// the form matches what's in the users profile.
156// The negative upload rate is typically much lower than the positive upload
157// rate.
158class AutofillUploadXmlParser : public AutofillXmlParser {
159 public:
160  AutofillUploadXmlParser(double* positive_upload_rate,
161                          double* negative_upload_rate);
162
163 private:
164  // A callback for the beginning of a new <element>, called by Expat.
165  // |context| is a parsing context used to resolve element/attribute names.
166  // |name| is the name of the element.
167  // |attrs| is the list of attributes (names and values) for the element.
168  virtual void StartElement(buzz::XmlParseContext* context,
169                            const char* name,
170                            const char** attrs) OVERRIDE;
171
172  // A helper function to retrieve double values from strings.  Raises an XML
173  // parse error if it fails.
174  // |context| is the current parsing context.
175  // |value| is the string to convert.
176  double GetDoubleValue(buzz::XmlParseContext* context, const char* attribute);
177
178  // True if parsing succeeded.
179  bool succeeded_;
180
181  double* positive_upload_rate_;
182  double* negative_upload_rate_;
183
184  DISALLOW_COPY_AND_ASSIGN(AutofillUploadXmlParser);
185};
186
187}  // namespace autofill
188
189#endif  // COMPONENTS_AUTOFILL_CORE_BROWSER_AUTOFILL_XML_PARSER_H_
190