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     private String url;
  28     private String desc;
  29     private String tz;
  30     private String schedule;
  31     private String target;
  32     private RetryParametersXml retryParameters;
  33
  34     /** Create an empty cron entry. */
  35     public Entry() {
  36       desc = "";
  37       tz = TZ_GMT;
  38       url = null;
  39       schedule = null;
  40       target = null;
  41       retryParameters = null;
  42     }
  43
  44     /** Records the human-readable description of this cron entry. */
  45     public void setDescription(String description) {
  46       this.desc = description.replace('\n', ' ');
  47     }
  48
  49     /** Records the URL of this cron entry */
  50     public void setUrl(String url) {
  51       this.url = url.replace('\n', ' ');
  52     }
  53
  54     /**
  55      * Records the schedule of this cron entry.  May throw
  56      * {@link AppEngineConfigException} if the schedule does not parse
  57      * correctly.
  58      *
  59      * @param schedule the schedule to save
  60      */
  61     public void setSchedule(String schedule) {
  62       schedule = schedule.replace('\n', ' ');
  63       this.schedule = schedule;
  64     }
  65
  66     /**
  67      * Sets the timezone for this cron entry's schedule.  Defaults to "GMT"
  68      * @param timezone timezone for the cron entry's {@code schedule}.
  69      */
  70     public void setTimezone(String timezone) {
  71       this.tz = timezone.replace('\n', ' ');
  72     }
  73
  74     public void setTarget(String target) {
  75       this.target = target;
  76     }
  77
  78     public void setRetryParameters(RetryParametersXml retryParameters) {
  79       this.retryParameters = retryParameters;
  80     }
  81
  82     public String getUrl() {
  83       return url;
  84     }
  85
  86     public String getDescription() {
  87       return desc;
  88     }
  89
  90     public String getSchedule() {
  91       return schedule;
  92     }
  93
  94     public String getTimezone() {
  95       return tz;
  96     }
  97
  98     public String getTarget() {
  99       return target;
 100     }
 101
 102     public RetryParametersXml getRetryParameters() {
 103       return retryParameters;
 104     }
 105
 106   }
 107
 108   private List<Entry> entries;
 109
 110   /** Create an empty configuration object. */
 111   public CronXml() {
 112     entries = new ArrayList<Entry>();
 113   }
 114
 115   /**
 116    * Puts a new entry into the list defined by the config file.
 117    *
 118    * @throws AppEngineConfigException if the previously-last entry is still
 119    *    incomplete.
 120    * @return the new entry
 121    */
 122   public Entry addNewEntry() {
 123     validateLastEntry();
 124     Entry entry = new Entry();
 125     entries.add(entry);
 126     return entry;
 127   }
 128
 129   /**
 130    * Puts an entry into the list defined by the config file.
 131    *
 132    * @throws AppEngineConfigException if the entry is still incomplete.
 133    */
 134   public void addEntry(Entry entry) {
 135     validateLastEntry();
 136     entries.add(entry);
 137     validateLastEntry();
 138   }
 139
 140   /**
 141    * Get the entries. Used for testing.
 142    */
 143   public List<Entry> getEntries() {
 144     return entries;
 145   }
 146
 147   /**
 148    * Check that the last entry defined is complete.
 149    * @throws AppEngineConfigException if it is not.
 150    */
 151   public void validateLastEntry() {
 152     if (entries.size() == 0) {
 153       return;
 154     }
 155     Entry last = entries.get(entries.size() - 1);
 156     if (last.getUrl() == null) {
 157       throw new AppEngineConfigException("no URL for cronentry");
 158     }
 159     if (last.getSchedule() == null) {
 160       throw new AppEngineConfigException("no schedule for cronentry " + last.getUrl());
 161     }
 162     try {
 163       GrocTimeSpecification parsedSchedule =
 164           GrocTimeSpecification.create(last.schedule);
 165     } catch (IllegalArgumentException iae) {
 166       throw new AppEngineConfigException("schedule " + last.schedule + " failed to parse",
 167                                          iae.getCause());
 168     }
 169   }
 170
 171   /**
 172    * Get the YAML equivalent of this cron.xml file.
 173    *
 174    * @return contents of an equivalent {@code cron.yaml} file.
 175    */
 176   public String toYaml() {
 177     validateLastEntry();
 178     StringBuilder builder = new StringBuilder("cron:\n");
 179     for (Entry ent : entries) {
 180       builder.append("- description: '" + ent.getDescription().replace("'", "''") + "'\n");
 181       builder.append("  url: " + ent.getUrl() + "\n");
 182       builder.append("  schedule: " + ent.getSchedule() + "\n");
 183       builder.append("  timezone: " + ent.getTimezone() + "\n");
 184       String target = ent.getTarget();
 185       if (target != null) {
 186         builder.append("  target: " + target + "\n");
 187       }
 188       RetryParametersXml retryParameters = ent.getRetryParameters();
 189       if (retryParameters != null) {
 190         builder.append(retryParameters.toYaml("job"));
 191       }
 192     }
 193     return builder.toString();
 194   }
 195 }