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