chrome/service/cloud_print/printer_job_queue_handler.cc

   1 // Copyright (c) 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 #include "chrome/service/cloud_print/printer_job_queue_handler.h"
   6
   7 #include <math.h>
   8
   9 #include <algorithm>
  10
  11 #include "base/values.h"
  12
  13 namespace cloud_print {
  14
  15 class TimeProviderImpl : public PrinterJobQueueHandler::TimeProvider {
  16  public:
  17   base::Time GetNow() override;
  18 };
  19
  20 base::Time TimeProviderImpl::GetNow() {
  21   return base::Time::Now();
  22 }
  23
  24 JobDetails::JobDetails() {}
  25
  26 JobDetails::~JobDetails() {}
  27
  28 void JobDetails::Clear() {
  29   job_id_.clear();
  30   job_title_.clear();
  31   print_ticket_.clear();
  32   print_ticket_mime_type_.clear();
  33   print_data_mime_type_.clear();
  34   print_data_file_path_ = base::FilePath();
  35   print_data_url_.clear();
  36   print_ticket_url_.clear();
  37   tags_.clear();
  38   time_remaining_ = base::TimeDelta();
  39 }
  40
  41 // static
  42 bool JobDetails::ordering(const JobDetails& first, const JobDetails& second) {
  43   return first.time_remaining_ < second.time_remaining_;
  44 }
  45
  46 PrinterJobQueueHandler::PrinterJobQueueHandler(TimeProvider* time_provider)
  47     : time_provider_(time_provider) {}
  48
  49 PrinterJobQueueHandler::PrinterJobQueueHandler()
  50     : time_provider_(new TimeProviderImpl()) {}
  51
  52 PrinterJobQueueHandler::~PrinterJobQueueHandler() {}
  53
  54 void PrinterJobQueueHandler::ConstructJobDetailsFromJson(
  55     const base::DictionaryValue* job_data,
  56     JobDetails* job_details) {
  57   job_details->Clear();
  58
  59   job_data->GetString(kIdValue, &job_details->job_id_);
  60   job_data->GetString(kTitleValue, &job_details->job_title_);
  61
  62   job_data->GetString(kTicketUrlValue, &job_details->print_ticket_url_);
  63   job_data->GetString(kFileUrlValue, &job_details->print_data_url_);
  64
  65   // Get tags for print job.
  66   const base::ListValue* tags = NULL;
  67   if (job_data->GetList(kTagsValue, &tags)) {
  68     for (size_t i = 0; i < tags->GetSize(); i++) {
  69       std::string value;
  70       if (tags->GetString(i, &value))
  71         job_details->tags_.push_back(value);
  72     }
  73   }
  74 }
  75
  76 base::TimeDelta PrinterJobQueueHandler::ComputeBackoffTime(
  77     const std::string& job_id) {
  78   FailedJobMap::const_iterator job_location = failed_job_map_.find(job_id);
  79   if (job_location == failed_job_map_.end()) {
  80     return base::TimeDelta();
  81   }
  82
  83   base::TimeDelta backoff_time =
  84       base::TimeDelta::FromSeconds(kJobFirstWaitTimeSecs);
  85   backoff_time *=
  86       // casting argument to double and result to uint64 to avoid compilation
  87       // issues
  88       static_cast<int64>(pow(
  89           static_cast<long double>(kJobWaitTimeExponentialMultiplier),
  90           job_location->second.retries_) + 0.5);
  91   base::Time scheduled_retry =
  92       job_location->second.last_retry_ + backoff_time;
  93   base::Time now = time_provider_->GetNow();
  94   base::TimeDelta time_remaining;
  95
  96   if (scheduled_retry < now) {
  97     return base::TimeDelta();
  98   }
  99   return scheduled_retry - now;
 100 }
 101
 102 void PrinterJobQueueHandler::GetJobsFromQueue(
 103     const base::DictionaryValue* json_data,
 104     std::vector<JobDetails>* jobs) {
 105   std::vector<JobDetails> jobs_with_timeouts;
 106
 107   jobs->clear();
 108
 109   const base::ListValue* job_list = NULL;
 110   if (!json_data->GetList(kJobListValue, &job_list)) {
 111     return;
 112   }
 113
 114   size_t list_size = job_list->GetSize();
 115   for (size_t cur_job = 0; cur_job < list_size; cur_job++) {
 116     const base::DictionaryValue* job_data = NULL;
 117     if (job_list->GetDictionary(cur_job, &job_data)) {
 118       JobDetails job_details_current;
 119       ConstructJobDetailsFromJson(job_data, &job_details_current);
 120
 121       job_details_current.time_remaining_ =
 122           ComputeBackoffTime(job_details_current.job_id_);
 123
 124       if (job_details_current.time_remaining_ == base::TimeDelta()) {
 125         jobs->push_back(job_details_current);
 126       } else {
 127         jobs_with_timeouts.push_back(job_details_current);
 128       }
 129     }
 130   }
 131
 132   sort(jobs_with_timeouts.begin(), jobs_with_timeouts.end(),
 133        &JobDetails::ordering);
 134   jobs->insert(jobs->end(), jobs_with_timeouts.begin(),
 135                jobs_with_timeouts.end());
 136 }
 137
 138 void PrinterJobQueueHandler::JobDone(const std::string& job_id) {
 139   failed_job_map_.erase(job_id);
 140 }
 141
 142 bool PrinterJobQueueHandler::JobFetchFailed(const std::string& job_id) {
 143   FailedJobMetadata metadata;
 144   metadata.retries_ = 0;
 145   metadata.last_retry_ = time_provider_->GetNow();
 146
 147   std::pair<FailedJobMap::iterator, bool> job_found =
 148       failed_job_map_.insert(FailedJobPair(job_id, metadata));
 149
 150   // If the job has already failed once, increment the number of retries.
 151   // If it has failed too many times, remove it from the map and tell the caller
 152   // to report a failure.
 153   if (!job_found.second) {
 154     if (job_found.first->second.retries_ >= kNumRetriesBeforeAbandonJob) {
 155       failed_job_map_.erase(job_found.first);
 156       return false;
 157     }
 158
 159     job_found.first->second.retries_ += 1;
 160     job_found.first->second.last_retry_ = time_provider_->GetNow();
 161   }
 162
 163   return true;
 164 }
 165
 166 }  // namespace cloud_print
 167