contacts: Add GDataContactsService.

chrome/browser/chromeos/gdata/gdata_contacts_service.cc

Index: chrome/browser/chromeos/gdata/gdata_contacts_service.cc
diff --git a/chrome/browser/chromeos/gdata/gdata_contacts_service.cc b/chrome/browser/chromeos/gdata/gdata_contacts_service.cc
new file mode 100644
index 0000000000000000000000000000000000000000..061aed6137db4c64d591d7b27d5b2e3363571963
--- /dev/null
+++ b/chrome/browser/chromeos/gdata/gdata_contacts_service.cc
@@ -0,0 +1,643 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/chromeos/gdata/gdata_contacts_service.h"
+
+#include <cstring>
+#include <string>
+#include <map>
+#include <utility>
+
+#include "base/json/json_writer.h"
+#include "base/logging.h"
+#include "base/stl_util.h"
+#include "base/values.h"
+#include "chrome/browser/chromeos/contacts/contact.h"
+#include "chrome/browser/chromeos/gdata/gdata_operation_registry.h"
+#include "chrome/browser/chromeos/gdata/gdata_operation_runner.h"
+#include "chrome/browser/chromeos/gdata/gdata_operations.h"
+#include "chrome/browser/chromeos/gdata/gdata_params.h"
+#include "chrome/browser/chromeos/gdata/gdata_util.h"
+#include "chrome/browser/image_decoder.h"
+#include "chrome/browser/profiles/profile.h"
+#include "content/public/browser/browser_thread.h"
+
+using content::BrowserThread;
+
+namespace gdata {
+
+namespace {
+
+// Maximum number of profile photos that we'll download at once.
+const int kMaxSimultaneousPhotoDownloads = 10;
+
+// Field in the top-level object containing the contacts feed.
+const char kFeedField[] = "feed";
+
+// Field in the contacts feed containing a list of category information, along
+// with fields within the dictionaries contained in the list and expected
+// values.
+const char kCategoryField[] = "category";
+const char kCategorySchemeField[] = "scheme";
+const char kCategorySchemeValue[] = "http://schemas.google.com/g/2005#kind";
+const char kCategoryTermField[] = "term";
+const char kCategoryTermValue[] =
+    "http://schemas.google.com/contact/2008#contact";
+
+// Field in the contacts feed containing a list of contact entries.
+const char kEntryField[] = "entry";
+
+// Top-level fields in contact entries.
+const char kIdField[] = "id.$t";
+const char kDeletedField[] = "gd$deleted";
+const char kFullNameField[] = "gd$name.gd$fullName.$t";
+const char kGivenNameField[] = "gd$name.gd$givenName.$t";
+const char kAdditionalNameField[] = "gd$name.gd$additionalName.$t";
+const char kFamilyNameField[] = "gd$name.gd$familyName.$t";
+const char kNamePrefixField[] = "gd$name.gd$namePrefix.$t";
+const char kNameSuffixField[] = "gd$name.gd$nameSuffix.$t";
+const char kEmailField[] = "gd$email";
+const char kPhoneField[] = "gd$phoneNumber";
+const char kPostalAddressField[] = "gd$structuredPostalAddress";
+const char kInstantMessagingField[] = "gd$im";
+const char kLinkField[] = "link";
+const char kUpdatedField[] = "updated.$t";
+
+// Fields in entries in the |kEmailField| list.
+const char kEmailAddressField[] = "address";
+
+// Fields in entries in the |kPhoneField| list.
+const char kPhoneNumberField[] = "$t";
+
+// Fields in entries in the |kPostalAddressField| list.
+const char kPostalAddressFormattedField[] = "gd$formattedAddress.$t";
+
+// Fields in entries in the |kInstantMessagingField| list.
+const char kInstantMessagingAddressField[] = "address";
+const char kInstantMessagingProtocolField[] = "protocol";
+const char kInstantMessagingProtocolAimValue[] =
+    "http://schemas.google.com/g/2005#AIM";
+const char kInstantMessagingProtocolMsnValue[] =
+    "http://schemas.google.com/g/2005#MSN";
+const char kInstantMessagingProtocolYahooValue[] =
+    "http://schemas.google.com/g/2005#YAHOO";
+const char kInstantMessagingProtocolSkypeValue[] =
+    "http://schemas.google.com/g/2005#SKYPE";
+const char kInstantMessagingProtocolQqValue[] =
+    "http://schemas.google.com/g/2005#QQ";
+const char kInstantMessagingProtocolGoogleTalkValue[] =
+    "http://schemas.google.com/g/2005#GOOGLE_TALK";
+const char kInstantMessagingProtocolIcqValue[] =
+    "http://schemas.google.com/g/2005#ICQ";
+const char kInstantMessagingProtocolJabberValue[] =
+    "http://schemas.google.com/g/2005#JABBER";
+
+// Generic fields shared between address-like items (email, postal, etc.).
+const char kAddressPrimaryField[] = "primary";
+const char kAddressPrimaryTrueValue[] = "true";
+const char kAddressRelField[] = "rel";
+const char kAddressRelHomeValue[] = "http://schemas.google.com/g/2005#home";
+const char kAddressRelWorkValue[] = "http://schemas.google.com/g/2005#work";
+const char kAddressRelMobileValue[] = "http://schemas.google.com/g/2005#mobile";
+const char kAddressLabelField[] = "label";
+
+// Fields in entries in the |kLinkField| list.
+const char kLinkHrefField[] = "href";
+const char kLinkRelField[] = "rel";
+const char kLinkETagField[] = "gd$etag";
+const char kLinkRelPhotoValue[] =
+    "http://schemas.google.com/contacts/2008/rel#photo";
+
+// Returns a string containing a pretty-printed JSON representation of |value|.
+std::string PrettyPrintValue(const base::Value& value) {
+  std::string out;
+  base::JSONWriter::WriteWithOptions(
+      &value, base::JSONWriter::OPTIONS_PRETTY_PRINT, &out);
+  return out;
+}
+
+// Returns whether an address is primary, given a dictionary representing a
+// single address.
+bool IsAddressPrimary(const DictionaryValue& address_dict) {
+  std::string primary;
+  address_dict.GetString(kAddressPrimaryField, &primary);
+  return primary == kAddressPrimaryTrueValue;
+}
+
+// Initializes a AddressType struct given a dictionary representing a single
+// address.
+void InitAddressType(const DictionaryValue& address_dict,
+                     contacts::Contact::AddressType* type) {
+  std::string rel;
+  address_dict.GetString(kAddressRelField, &rel);
+  if (rel == kAddressRelHomeValue)
+    type->relation = contacts::Contact::AddressType::RELATION_HOME;
+  else if (rel == kAddressRelWorkValue)
+    type->relation = contacts::Contact::AddressType::RELATION_WORK;
+  else if (rel == kAddressRelMobileValue)
+    type->relation = contacts::Contact::AddressType::RELATION_MOBILE;
+  else
+    type->relation = contacts::Contact::AddressType::RELATION_OTHER;
+
+  address_dict.GetString(kAddressLabelField, &(type->label));
+}
+
+// Maps the protocol from a dictionary representing a contact's IM address to a
+// contacts::Contact::InstantMessagingAddress::Protocol value.
+contacts::Contact::InstantMessagingAddress::Protocol
+GetInstantMessagingProtocol(const DictionaryValue& im_dict) {
+  std::string protocol;
+  im_dict.GetString(kInstantMessagingProtocolField, &protocol);
+  if (protocol == kInstantMessagingProtocolAimValue)
+    return contacts::Contact::InstantMessagingAddress::PROTOCOL_AIM;
+  else if (protocol == kInstantMessagingProtocolMsnValue)
+    return contacts::Contact::InstantMessagingAddress::PROTOCOL_MSN;
+  else if (protocol == kInstantMessagingProtocolYahooValue)
+    return contacts::Contact::InstantMessagingAddress::PROTOCOL_YAHOO;
+  else if (protocol == kInstantMessagingProtocolSkypeValue)
+    return contacts::Contact::InstantMessagingAddress::PROTOCOL_SKYPE;
+  else if (protocol == kInstantMessagingProtocolQqValue)
+    return contacts::Contact::InstantMessagingAddress::PROTOCOL_QQ;
+  else if (protocol == kInstantMessagingProtocolGoogleTalkValue)
+    return contacts::Contact::InstantMessagingAddress::PROTOCOL_GOOGLE_TALK;
+  else if (protocol == kInstantMessagingProtocolIcqValue)
+    return contacts::Contact::InstantMessagingAddress::PROTOCOL_ICQ;
+  else if (protocol == kInstantMessagingProtocolJabberValue)
+    return contacts::Contact::InstantMessagingAddress::PROTOCOL_JABBER;
+  else
+    return contacts::Contact::InstantMessagingAddress::PROTOCOL_OTHER;
+}
+
+// Assigns the photo URL from a contact's dictionary (within the "entry" list)
+// to |url|.  Returns true on success.
+bool GetPhotoUrl(const DictionaryValue& dict, std::string* url) {

[satorux1, 2012/07/24 18:25:51]

it may be slightly simpler to return an empty string on error, than a bool +
string*?

[Daniel Erat, 2012/07/24 20:37:21]

Done.

+  DCHECK(url);
+  ListValue* link_list = NULL;
+  if (!dict.GetList(kLinkField, &link_list))
+    return false;
+
+  for (size_t i = 0; i < link_list->GetSize(); ++i) {
+    DictionaryValue* link_dict = NULL;
+    if (!link_list->GetDictionary(i, &link_dict))
+      continue;
+
+    std::string rel;
+    if (!link_dict->GetString(kLinkRelField, &rel))
+      continue;
+    if (rel != kLinkRelPhotoValue)
+      continue;
+
+    // From https://goo.gl/7T6Od: "If a contact does not have a photo, then the
+    // photo link element has no gd:etag attribute."
+    std::string etag;
+    if (!link_dict->GetString(kLinkETagField, &etag))
+      continue;
+
+    if (link_dict->GetString(kLinkHrefField, url))
+      return true;
+  }
+  return false;
+}
+
+// Fills a Contact's fields using an entry from a GData feed.
+bool FillContactFromDictionary(const base::DictionaryValue& dict,

[satorux1, 2012/07/24 18:25:51]

this function is lengthy. Would it make sense to use
base/json/json_value_converter.h, with which you can parse JSON values in a
declarative manner?

For Drive stuff, json_value_converter.h reduced a lot of code from a
hand-written parser.

[Daniel Erat, 2012/07/24 20:37:21]

Heh, see my very old, abandoned change at
https://chromiumcodereview.appspot.com/10440101/.  I'll also forward you the
email discussion that Jun and I had about this before I ultimately decided that
JSONValueConverter wouldn't save much work.

I could probably move the similar email/phone/address/im code into a templated
function that also takes a callback to handle the additional protocol field for
IM addresses, if you think it'd improve things.  Templates often make things
worse instead of better, though. :-)

+                               contacts::Contact* contact) {
+  DCHECK(contact);
+  if (!dict.GetString(kIdField, &(contact->provider_id)))
+    return false;
+
+  std::string updated;
+  if (dict.GetString(kUpdatedField, &updated)) {
+    if (!util::GetTimeFromString(updated, &(contact->update_time))) {
+      LOG(WARNING) << "Unable to parse time \"" << updated << "\"";
+      return false;
+    }
+  }
+
+  base::Value* deleted_value = NULL;
+  contact->deleted = dict.Get(kDeletedField, &deleted_value);
+  if (contact->deleted)
+    return true;
+
+  dict.GetString(kFullNameField, &(contact->full_name));
+  dict.GetString(kGivenNameField, &(contact->given_name));
+  dict.GetString(kAdditionalNameField, &(contact->additional_name));
+  dict.GetString(kFamilyNameField, &(contact->family_name));
+  dict.GetString(kNamePrefixField, &(contact->name_prefix));
+  dict.GetString(kNameSuffixField, &(contact->name_suffix));
+
+  ListValue* email_list = NULL;
+  if (dict.GetList(kEmailField, &email_list)) {
+    for (size_t i = 0; i < email_list->GetSize(); ++i) {
+      DictionaryValue* email_dict = NULL;
+      if (!email_list->GetDictionary(i, &email_dict))
+        return false;
+
+      contacts::Contact::EmailAddress email;
+      if (!email_dict->GetString(kEmailAddressField, &email.address))
+        return false;
+
+      email.primary = IsAddressPrimary(*email_dict);
+      InitAddressType(*email_dict, &email.type);
+      contact->email_addresses.push_back(email);
+    }
+  }
+
+  ListValue* phone_list = NULL;
+  if (dict.GetList(kPhoneField, &phone_list)) {
+    for (size_t i = 0; i < phone_list->GetSize(); ++i) {
+      DictionaryValue* phone_dict = NULL;
+      if (!phone_list->GetDictionary(i, &phone_dict))
+        return false;
+
+      contacts::Contact::PhoneNumber phone;
+      if (!phone_dict->GetString(kPhoneNumberField, &phone.number))
+        return false;
+
+      phone.primary = IsAddressPrimary(*phone_dict);
+      InitAddressType(*phone_dict, &phone.type);
+      contact->phone_numbers.push_back(phone);
+    }
+  }
+
+  ListValue* address_list = NULL;
+  if (dict.GetList(kPostalAddressField, &address_list)) {
+    for (size_t i = 0; i < address_list->GetSize(); ++i) {
+      DictionaryValue* address_dict = NULL;
+      if (!address_list->GetDictionary(i, &address_dict))
+        return false;
+
+      contacts::Contact::PostalAddress address;
+      if (!address_dict->GetString(kPostalAddressFormattedField,
+                                   &address.address)) {
+        return false;
+      }
+      address.primary = IsAddressPrimary(*address_dict);
+      InitAddressType(*address_dict, &address.type);
+      contact->postal_addresses.push_back(address);
+    }
+  }
+
+  ListValue* im_list = NULL;
+  if (dict.GetList(kInstantMessagingField, &im_list)) {
+    for (size_t i = 0; i < im_list->GetSize(); ++i) {
+      DictionaryValue* im_dict = NULL;
+      if (!im_list->GetDictionary(i, &im_dict))
+        return false;
+
+      contacts::Contact::InstantMessagingAddress im;
+      if (!im_dict->GetString(kInstantMessagingAddressField, &im.address))
+        return false;
+      im.primary = IsAddressPrimary(*im_dict);
+      InitAddressType(*im_dict, &im.type);
+      im.protocol = GetInstantMessagingProtocol(*im_dict);
+      contact->instant_messaging_addresses.push_back(im);
+    }
+  }
+
+  return true;
+}
+
+}  // namespace
+
+class GDataContactsService::DownloadContactsRequest
+    : public ImageDecoder::Delegate {
+ public:
+  DownloadContactsRequest(GDataContactsService* service,
+                          Profile* profile,
+                          GDataOperationRunner* runner,
+                          SuccessCallback success_callback,
+                          FailureCallback failure_callback,
+                          const base::Time& min_update_time,
+                          int max_simultaneous_photo_downloads)
+      : service_(service),
+        profile_(profile),
+        runner_(runner),
+        success_callback_(success_callback),
+        failure_callback_(failure_callback),
+        min_update_time_(min_update_time),
+        contacts_(new ScopedVector<contacts::Contact>),
+        max_simultaneous_photo_downloads_(max_simultaneous_photo_downloads),
+        num_in_progress_photo_downloads_(0),
+        photo_download_failed_(false) {
+    DCHECK(service_);
+    DCHECK(profile_);
+    DCHECK(runner_);
+  }
+
+  ~DownloadContactsRequest() {
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    // Abandon any outstanding image decode requests.
+    for (ImageDecoderContactMap::iterator it =
+             in_progress_photo_decodes_.begin();
+         it != in_progress_photo_decodes_.end(); ++it) {
+      it->first->set_delegate(NULL);
+    }
+    service_ = NULL;
+    profile_ = NULL;
+    runner_ = NULL;
+  }
+
+  void Run() {
+    GetContactsOperation* operation =
+        new GetContactsOperation(
+            runner_->operation_registry(),
+            profile_,
+            min_update_time_,
+            base::Bind(&DownloadContactsRequest::HandleFeedData,
+                       base::Unretained(this)));
+    if (!service_->feed_url_for_testing_.is_empty())
+      operation->set_feed_url_for_testing(service_->feed_url_for_testing_);
+
+    runner_->StartOperationWithRetry(operation);
+  }
+
+  // ImageDecoder::Delegate overrides:
+  virtual void OnImageDecoded(const ImageDecoder* decoder,
+                              const SkBitmap& decoded_image) OVERRIDE {
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    ImageDecoderContactMap::iterator it =
+        in_progress_photo_decodes_.find(const_cast<ImageDecoder*>(decoder));
+    CHECK(it != in_progress_photo_decodes_.end());
+    contacts::Contact* contact = it->second;
+    VLOG(1) << "Downloaded and decoded " << decoded_image.width() << "x"
+            << decoded_image.height() << " photo for " << contact->provider_id;
+    contact->photo = decoded_image;
+    in_progress_photo_decodes_.erase(it);
+    CheckCompletion();
+  }
+
+  virtual void OnDecodeImageFailed(const ImageDecoder* decoder) OVERRIDE {
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    ImageDecoderContactMap::iterator it =
+        in_progress_photo_decodes_.find(const_cast<ImageDecoder*>(decoder));
+    CHECK(it != in_progress_photo_decodes_.end());
+    contacts::Contact* contact = it->second;
+    LOG(WARNING) << "Failed to decode image for contact "
+                 << contact->provider_id;
+    // Leave the photo blank but don't abort the entire download request.
+    in_progress_photo_decodes_.erase(it);
+    CheckCompletion();
+  }
+
+ private:
+  // Callback for GetContactsOperation calls.
+  void HandleFeedData(GDataErrorCode error,
+                      scoped_ptr<base::Value> feed_data) {
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    if (error != HTTP_SUCCESS) {
+      LOG(WARNING) << "Got error " << error << " while downloading contacts";
+      failure_callback_.Run();
+      service_->OnRequestComplete(this);
+      return;
+    }
+
+    VLOG(2) << "Got feed data:\n" << PrettyPrintValue(*(feed_data.get()));
+    if (!ProcessFeedData(*feed_data.get())) {
+      LOG(WARNING) << "Unable to process feed data";
+      failure_callback_.Run();
+      service_->OnRequestComplete(this);
+      return;
+    }
+
+    CheckCompletion();
+  }
+
+  // Processes the raw contacts feed from |feed_data| and fills |contacts_|.
+  // Returns true on success.
+  bool ProcessFeedData(const base::Value& feed_data) {
+    const DictionaryValue* toplevel_dict = NULL;
+    if (!feed_data.GetAsDictionary(&toplevel_dict)) {
+      LOG(WARNING) << "Top-level object is not a dictionary";
+      return false;
+    }
+
+    DictionaryValue* feed_dict = NULL;
+    if (!toplevel_dict->GetDictionary(kFeedField, &feed_dict)) {
+      LOG(WARNING) << "Feed dictionary missing";
+      return false;
+    }
+
+    // Check the category field to confirm that this is actually a contact feed.
+    ListValue* category_list = NULL;
+    if (!feed_dict->GetList(kCategoryField, &category_list)) {
+      LOG(WARNING) << "Category list missing";
+      return false;
+    }
+    DictionaryValue* category_dict = NULL;
+    if (!category_list->GetSize() == 1 ||
+        !category_list->GetDictionary(0, &category_dict)) {
+      LOG(WARNING) << "Unable to get dictionary from category list of size "
+                   << category_list->GetSize();
+      return false;
+    }
+    std::string category_scheme, category_term;
+    if (!category_dict->GetString(kCategorySchemeField, &category_scheme) ||
+        !category_dict->GetString(kCategoryTermField, &category_term) ||
+        category_scheme != kCategorySchemeValue ||
+        category_term != kCategoryTermValue) {
+      LOG(WARNING) << "Unexpected category (scheme was \"" << category_scheme
+                   << "\", term was \"" << category_term << "\")";
+      return false;
+    }
+
+    // A missing entry list means no entries (maybe we're doing an incremental
+    // update and nothing has changed).
+    ListValue* entry_list = NULL;
+    if (!feed_dict->GetList(kEntryField, &entry_list))
+      return true;
+
+    contacts_needing_photo_downloads_.reserve(entry_list->GetSize());
+
+    for (ListValue::const_iterator entry_it = entry_list->begin();
+         entry_it != entry_list->end(); ++entry_it) {
+      const size_t index = (entry_it - entry_list->begin());
+      const DictionaryValue* contact_dict = NULL;
+      if (!(*entry_it)->GetAsDictionary(&contact_dict)) {
+        LOG(WARNING) << "Entry " << index << " isn't a dictionary";
+        return false;
+      }
+
+      scoped_ptr<contacts::Contact> contact(new contacts::Contact);
+      if (!FillContactFromDictionary(*contact_dict, contact.get())) {
+        LOG(WARNING) << "Unable to fill entry " << index;
+        return false;
+      }
+
+      VLOG(1) << "Got contact " << index << ":"
+              << " id=" << contact->provider_id
+              << " full_name=\"" << contact->full_name << "\""
+              << " update_time=" << contact->update_time.ToDoubleT();
+
+      std::string photo_url;
+      if (GetPhotoUrl(*contact_dict, &photo_url)) {
+        if (!service_->feed_url_for_testing_.is_empty()) {
+          photo_url =
+              service_->rewrite_photo_url_callback_for_testing_.Run(photo_url);
+        }
+        contact_photo_urls_[contact.get()] = photo_url;
+        contacts_needing_photo_downloads_.push_back(contact.get());
+      }
+
+      contacts_->push_back(contact.release());
+    }
+
+    return true;
+  }
+
+  // If we're done downloading and decoding photos, invokes a callback and
+  // deletes |this|.  Otherwise, starts one or more downloads of URLs from
+  // |contacts_needing_photo_downloads_|.
+  void CheckCompletion() {
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    if (contacts_needing_photo_downloads_.empty() &&
+        num_in_progress_photo_downloads_ == 0 &&
+        in_progress_photo_decodes_.empty()) {
+      VLOG(1) << "Done downloading and decoding photos; invoking callback";
+      if (photo_download_failed_)
+        failure_callback_.Run();
+      else
+        success_callback_.Run(contacts_.Pass());
+      service_->OnRequestComplete(this);
+      return;
+    }
+
+    while (!contacts_needing_photo_downloads_.empty() &&
+           (num_in_progress_photo_downloads_ <
+            max_simultaneous_photo_downloads_)) {
+      contacts::Contact* contact = contacts_needing_photo_downloads_.back();
+      contacts_needing_photo_downloads_.pop_back();
+      DCHECK(contact_photo_urls_.count(contact));
+      std::string url = contact_photo_urls_[contact];
+
+      VLOG(1) << "Starting download of photo " << url << " for "
+              << contact->provider_id;
+      runner_->StartOperationWithRetry(
+          new GetContactPhotoOperation(
+              runner_->operation_registry(),
+              profile_,
+              GURL(url),
+              base::Bind(&DownloadContactsRequest::HandlePhotoData,
+                         base::Unretained(this),
+                         base::Unretained(contact))));
+      num_in_progress_photo_downloads_++;
+    }
+  }
+
+  // Callback for GetContactPhotoOperation calls.  Decodes the image data,
+  // updates the associated Contact, and checks for completion.
+  void HandlePhotoData(contacts::Contact* contact,
+                       GDataErrorCode error,
+                       scoped_ptr<std::string> download_data) {
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    VLOG(1) << "Got photo data for " << contact->provider_id
+            << " (error=" << error << " size=" << download_data->size() << ")";
+    num_in_progress_photo_downloads_--;
+
+    if (error != HTTP_SUCCESS) {
+      LOG(WARNING) << "Got error " << error << " while downloading photo "
+                   << "for " << contact->provider_id;
+      // TODO(derat): Retry several times for temporary failures?
+      photo_download_failed_ = true;
+      // Make sure we don't start any more downloads.
+      contacts_needing_photo_downloads_.clear();
+      CheckCompletion();
+      return;
+    }
+
+    scoped_refptr<ImageDecoder> image_decoder =
+        new ImageDecoder(this, *(download_data.get()));
+    in_progress_photo_decodes_.insert(
+        std::make_pair(image_decoder.get(), contact));
+    image_decoder->Start();
+  }
+
+ private:
+  typedef std::map<contacts::Contact*, std::string> ContactPhotoUrls;
+  typedef std::map<ImageDecoder*, contacts::Contact*> ImageDecoderContactMap;
+
+  GDataContactsService* service_;  // not owned
+  Profile* profile_;  // not owned
+  GDataOperationRunner* runner_;  // not owned
+
+  SuccessCallback success_callback_;
+  FailureCallback failure_callback_;
+
+  base::Time min_update_time_;
+
+  scoped_ptr<ScopedVector<contacts::Contact> > contacts_;
+
+  // Map from a contact to the URL at which its photo is located.
+  // Contacts without photos do not appear in this map.
+  ContactPhotoUrls contact_photo_urls_;
+
+  // Contacts that have photos that we still need to start downloading.
+  // When we start a download, the contact is removed from this list.
+  std::vector<contacts::Contact*> contacts_needing_photo_downloads_;
+
+  // Maximum number of photos we'll try to download at once.
+  int max_simultaneous_photo_downloads_;
+
+  // Number of in-progress photo downloads.
+  int num_in_progress_photo_downloads_;
+
+  // Did we encounter a fatal error while downloading a photo?
+  bool photo_download_failed_;
+
+  // Maps from an ImageDecoder to the contact whose photo it's decoding.
+  ImageDecoderContactMap in_progress_photo_decodes_;
+
+  DISALLOW_COPY_AND_ASSIGN(DownloadContactsRequest);
+};
+
+GDataContactsService::GDataContactsService(Profile* profile)
+    : profile_(profile),
+      runner_(new GDataOperationRunner(profile)),
+      max_simultaneous_photo_downloads_(kMaxSimultaneousPhotoDownloads) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(profile_);
+}
+
+GDataContactsService::~GDataContactsService() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  STLDeleteContainerPointers(requests_.begin(), requests_.end());
+  requests_.clear();
+  runner_->CancelAll();
+}
+
+GDataAuthService* GDataContactsService::auth_service_for_testing() {
+  return runner_->auth_service();
+}
+
+void GDataContactsService::Initialize() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  runner_->Initialize();
+}
+
+void GDataContactsService::DownloadContacts(SuccessCallback success_callback,
+                                            FailureCallback failure_callback,
+                                            const base::Time& min_update_time) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DownloadContactsRequest* request =
+      new DownloadContactsRequest(this,
+                                  profile_,
+                                  runner_.get(),
+                                  success_callback,
+                                  failure_callback,
+                                  min_update_time,
+                                  max_simultaneous_photo_downloads_);
+  VLOG(1) << "Starting contacts download with request " << request;
+  requests_.insert(request);
+  request->Run();
+}
+
+void GDataContactsService::OnRequestComplete(DownloadContactsRequest* request) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(request);
+  VLOG(1) << "Download request " << request << " complete";
+  requests_.erase(request);
+  delete request;
+}
+
+}  // namespace contacts