Enable import/export of passwords into/from Password Manager

components/password_manager/core/browser/export/password_exporter.cc

Index: components/password_manager/core/browser/export/password_exporter.cc
diff --git a/components/password_manager/core/browser/export/password_exporter.cc b/components/password_manager/core/browser/export/password_exporter.cc
new file mode 100644
index 0000000000000000000000000000000000000000..91073c2c73f9371225ffc67f347330d1a44d1273
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+++ b/components/password_manager/core/browser/export/password_exporter.cc
@@ -0,0 +1,140 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.

[vabr (Chromium), 2016/03/10 10:53:32]

2016

[xunlu, 2016/03/16 07:23:59]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/password_manager/core/browser/export/password_exporter.h"
+
+#include "base/bind.h"
+#include "base/files/file_util.h"
+#include "base/location.h"
+#include "base/strings/utf_string_conversions.h"
+#include "base/task_runner.h"
+#include "base/values.h"
+#include "components/autofill/core/common/password_form.h"
+#include "components/password_manager/core/browser/export/csv_writer.h"
+
+namespace password_manager {
+
+namespace {
+
+using autofill::PasswordForm;
+
+// PasswordWriterBase ---------------------------------------------------------
+
+// Interface for writing a list of passwords into various formats.
+class PasswordWriterBase {
+ public:
+  virtual ~PasswordWriterBase() = 0;
+
+  // Serializes the list of |passwords|.
+  virtual std::string SerializePasswords(
+      std::vector<scoped_ptr<PasswordForm>>& passwords) = 0;
+};
+
+PasswordWriterBase::~PasswordWriterBase() {}
+
+// PasswordCSVWriter ----------------------------------------------------------
+
+class PasswordCSVWriter : public PasswordWriterBase {
+ public:
+  static const base::FilePath::CharType kFileExtension[];
+
+  PasswordCSVWriter() {}
+
+  // PasswordWriterBase:
+  std::string SerializePasswords(
+      std::vector<scoped_ptr<PasswordForm>>& passwords) override {
+    std::vector<std::string> header;
+    header.push_back(kTitleFieldName);
+    header.push_back(kUrlFieldName);
+    header.push_back(kUsernameFieldName);
+    header.push_back(kPasswordFieldName);
+
+    std::vector<ColumnNameToValueMap> records;
+    records.reserve(passwords.size());
+    for (const auto& it : passwords) {
+      records.push_back(PasswordFormToRecord(it.get()));
+    }
+    std::string result;
+    WriteCSV(header, records, &result);
+    return result;
+  }
+
+ private:
+  static const char kUrlFieldName[];
+  static const char kUsernameFieldName[];
+  static const char kPasswordFieldName[];
+  static const char kTitleFieldName[];
+
+  ColumnNameToValueMap PasswordFormToRecord(const PasswordForm* form) {
+    ColumnNameToValueMap record;
+    record[kUrlFieldName] = (form->origin).spec();
+    record[kUsernameFieldName] = base::UTF16ToUTF8(form->username_value);
+    record[kPasswordFieldName] = base::UTF16ToUTF8(form->password_value);
+    record[kTitleFieldName] = form->origin.host();
+    return record;
+  }
+
+  DISALLOW_COPY_AND_ASSIGN(PasswordCSVWriter);
+};
+
+const base::FilePath::CharType PasswordCSVWriter::kFileExtension[] =
+    FILE_PATH_LITERAL("csv");
+const char PasswordCSVWriter::kUrlFieldName[] = "url";
+const char PasswordCSVWriter::kUsernameFieldName[] = "username";
+const char PasswordCSVWriter::kPasswordFieldName[] = "password";
+const char PasswordCSVWriter::kTitleFieldName[] = "name";
+
+// Helper ---------------------------------------------------------------------
+
+void WriteToFile(const base::FilePath& path, const std::string& data) {
+  base::WriteFile(path, data.c_str(), data.size());
+}
+
+}  // namespace
+
+// static
+void PasswordExporter::Export(
+    const base::FilePath& path,
+    std::vector<scoped_ptr<PasswordForm>> passwords,
+    scoped_refptr<base::TaskRunner> blocking_task_runner,
+    const base::Closure& completion) {
+  scoped_ptr<PasswordWriterBase> password_writer(new PasswordCSVWriter);
+
+  bool is_extension_valid = false;
+  if (!path.Extension().empty() &&
+      path.Extension().substr(1) == PasswordCSVWriter::kFileExtension)
+    is_extension_valid = true;
+
+  std::string serialized_passwords =
+      password_writer->SerializePasswords(passwords);
+
+  if (completion.is_null()) {
+    blocking_task_runner->PostTask(
+        FROM_HERE,
+        base::Bind(&WriteToFile,
+                   is_extension_valid ? path : path.ReplaceExtension(

[vabr (Chromium), 2016/03/10 10:53:32]

Do I understand correctly that if the user selects "a.txt" as the target file,
then Chrome will instead rewrite the content of "a.csv"? That sounds dangerous!
Why do we force the extension on the user?

[xunlu, 2016/03/16 07:23:59]

In the exporter dialog UI there is a drop down for output type and we currently
only have CSV there. So the user really should only expect the output to be CSV.
If we allow them to specify what ever extension they want and they specify
something like "json" but it's actually CSV inside, there will be some
confusions.

I'll leave it for you to decide.

[vabr (Chromium), 2016/03/16 17:48:28]

Confusions are one thing, but an overwritten content sounds worse.
While I do not understand completely, whether the drop-down with extensions only
having CSV means that the user cannot return a file name with another extension,
or that it just will be harder (need to type it or something like that), I still
think not changing the name here is the safe option: in the former case there is
no difference, and in the latter my original concern with overwriting files
applies.

[xunlu, 2016/03/18 21:15:30]

I vaguely remember that we were going to use the extension to determine the
proper writer. But since we only have CSVWriter now it's probably fine. So I'm
going to remove the is_extension_valid logic as you suggested. Should you need
to support more output format in the future, please update this part
accordingly.

[vabr (Chromium), 2016/03/21 14:01:30]

I acknowledge that if support for other formats is added, then the code will
need appropriate changes.
Suggesting the .csv extension as the default choice to the user sounds fine, but
the code should avoid too much generality and complexity for handling multiple
extensions, until there is a real need to handle multiple extensions.

[xunlu, 2016/03/22 07:17:15]

Acknowledged.

+                                                   FILE_PATH_LITERAL("csv")),
+                   serialized_passwords));
+
+  } else {
+    blocking_task_runner->PostTaskAndReply(
+        FROM_HERE,
+        base::Bind(&WriteToFile,
+                   is_extension_valid ? path : path.ReplaceExtension(
+                                                   FILE_PATH_LITERAL("csv")),
+                   serialized_passwords),
+        completion);
+  }
+}
+
+// static
+std::vector<std::vector<base::FilePath::StringType>>
+PasswordExporter::GetSupportedFileExtensions() {
+  std::vector<std::vector<base::FilePath::StringType>> extensions;
+  extensions.resize(1);
+  extensions[0].push_back(PasswordCSVWriter::kFileExtension);
+  return extensions;
+}
+
+}  // namespace password_manager