java/src/main/com/google/apphosting/utils/config/CronXml.java

   1 // Copyright 2009 Google Inc. All Rights Reserved.
   2
   3 package com.google.apphosting.utils.config;
   4
   5 import com.google.cron.GrocTimeSpecification;
   6
   7 import java.util.ArrayList;
   8 import java.util.List;
   9
  10 /**
  11  * Parsed cron.xml file.
  12  *
  13  * Any additions to this class should also be made to the YAML
  14  * version in CronYamlReader.java.
  15  *
  16  */
  17 public class CronXml {
  18
  19   /**
  20    * Describes a single cron entry.
  21    *
  22    */
  23   public static class Entry {
  24
  25     private static final String TZ_GMT = "UTC";
  26
  27     String url;
  28     String desc;
  29     String tz;
  30     String schedule;
  31     String target;
  32
  33     /** Create an empty cron entry. */
  34     public Entry() {
  35       desc = "";
  36       tz = TZ_GMT;
  37       url = null;
  38       schedule = null;
  39       target = null;
  40     }
  41
  42     /** Records the human-readable description of this cron entry. */
  43     public void setDescription(String description) {
  44       this.desc = description.replace('\n', ' ');
  45     }
  46
  47     /** Records the URL of this cron entry */
  48     public void setUrl(String url) {
  49       this.url = url.replace('\n', ' ');
  50     }
  51
  52     /**
  53      * Records the schedule of this cron entry.  May throw
  54      * {@link AppEngineConfigException} if the schedule does not parse
  55      * correctly.
  56      *
  57      * @param schedule the schedule to save
  58      */
  59     public void setSchedule(String schedule) {
  60       schedule = schedule.replace('\n', ' ');
  61       this.schedule = schedule;
  62     }
  63
  64     /**
  65      * Sets the timezone for this cron entry's schedule.  Defaults to "GMT"
  66      * @param timezone timezone for the cron entry's {@code schedule}.
  67      */
  68     public void setTimezone(String timezone) {
  69       this.tz = timezone.replace('\n', ' ');
  70     }
  71
  72     public void setTarget(String target) {
  73       this.target = target;
  74     }
  75
  76     public String getUrl() {
  77       return url;
  78     }
  79
  80     public String getDescription() {
  81       return desc;
  82     }
  83
  84     public String getSchedule() {
  85       return schedule;
  86     }
  87
  88     public String getTimezone() {
  89       return tz;
  90     }
  91
  92     public String getTarget() {
  93       return target;
  94     }
  95
  96   }
  97
  98   private List<Entry> entries;
  99
 100   /** Create an empty configuration object. */
 101   public CronXml() {
 102     entries = new ArrayList<Entry>();
 103   }
 104
 105   /**
 106    * Puts a new entry into the list defined by the config file.
 107    *
 108    * @throws AppEngineConfigException if the previously-last entry is still
 109    *    incomplete.
 110    * @return the new entry
 111    */
 112   public Entry addNewEntry() {
 113     validateLastEntry();
 114     Entry entry = new Entry();
 115     entries.add(entry);
 116     return entry;
 117   }
 118
 119   /**
 120    * Puts an entry into the list defined by the config file.
 121    *
 122    * @throws AppEngineConfigException if the entry is still incomplete.
 123    */
 124   public void addEntry(Entry entry) {
 125     validateLastEntry();
 126     entries.add(entry);
 127     validateLastEntry();
 128   }
 129
 130   /**
 131    * Get the entries. Used for testing.
 132    */
 133   public List<Entry> getEntries() {
 134     return entries;
 135   }
 136
 137   /**
 138    * Check that the last entry defined is complete.
 139    * @throws AppEngineConfigException if it is not.
 140    */
 141   public void validateLastEntry() {
 142     if (entries.size() == 0) {
 143       return;
 144     }
 145     Entry last = entries.get(entries.size() - 1);
 146     if (last.getUrl() == null) {
 147       throw new AppEngineConfigException("no URL for cronentry");
 148     }
 149     if (last.getSchedule() == null) {
 150       throw new AppEngineConfigException("no schedule for cronentry " + last.getUrl());
 151     }
 152     try {
 153       GrocTimeSpecification parsedSchedule =
 154           GrocTimeSpecification.create(last.schedule);
 155     } catch (IllegalArgumentException iae) {
 156       throw new AppEngineConfigException("schedule " + last.schedule + " failed to parse",
 157                                          iae.getCause());
 158     }
 159   }
 160
 161   /**
 162    * Get the YAML equivalent of this cron.xml file.
 163    *
 164    * @return contents of an equivalent {@code cron.yaml} file.
 165    */
 166   public String toYaml() {
 167     StringBuilder builder = new StringBuilder("cron:\n");
 168     for (Entry ent : entries) {
 169       builder.append("- description: '" + ent.getDescription().replace("'", "''") + "'\n");
 170       builder.append("  url: " + ent.getUrl() + "\n");
 171       builder.append("  schedule: " + ent.getSchedule() + "\n");
 172       builder.append("  timezone: " + ent.getTimezone() + "\n");
 173       String target = ent.getTarget();
 174       if (target != null) {
 175         builder.append("  target: " + target + "\n");
 176       }
 177     }
 178     return builder.toString();
 179   }
 180 }