root / trunk / hammock / src / net35 / Hammock / Tasks / TimedTask.cs @ 0eea575a
History | View | Annotate | Download (7.4 kB)
| 1 |
using System; |
|---|---|
| 2 |
using System.Diagnostics; |
| 3 |
using System.Threading; |
| 4 |
using Hammock.Web; |
| 5 |
|
| 6 |
#if SILVERLIGHT |
| 7 |
using Hammock.Silverlight.Compat; |
| 8 |
#endif |
| 9 |
namespace Hammock.Tasks |
| 10 |
{
|
| 11 |
public class TimedTask : ITimedTask |
| 12 |
{
|
| 13 |
protected readonly object Lock = new object(); |
| 14 |
protected bool Active; |
| 15 |
protected int Iterations; |
| 16 |
protected Timer Timer; |
| 17 |
protected bool ContinueOnError; |
| 18 |
|
| 19 |
public Action<bool> Action { get; protected set; }
|
| 20 |
public Exception Exception { get; protected set; }
|
| 21 |
public TimeSpan DueTime { get; protected set; }
|
| 22 |
public TimeSpan Interval { get; protected set; }
|
| 23 |
internal WebQueryAsyncResult AsyncResult { get; set; }
|
| 24 |
public event Action<TimedTask, EventArgs> Stopped; |
| 25 |
|
| 26 |
public TimedTask(TimeSpan due, |
| 27 |
TimeSpan interval, |
| 28 |
int iterations, |
| 29 |
bool continueOnError, |
| 30 |
Action<bool> action) : |
| 31 |
this(due, interval, iterations, action) |
| 32 |
{
|
| 33 |
ContinueOnError = continueOnError; |
| 34 |
} |
| 35 |
|
| 36 |
public TimedTask(TimeSpan due, |
| 37 |
TimeSpan interval, |
| 38 |
int iterations, |
| 39 |
Action<bool> action) |
| 40 |
{
|
| 41 |
DueTime = due; |
| 42 |
Interval = interval; |
| 43 |
Iterations = iterations; |
| 44 |
Action = action; |
| 45 |
} |
| 46 |
|
| 47 |
protected virtual void Start(bool continueOnError) |
| 48 |
{
|
| 49 |
var count = 0; |
| 50 |
Timer = new Timer(state => |
| 51 |
{
|
| 52 |
try |
| 53 |
{
|
| 54 |
Action(false); |
| 55 |
count++; |
| 56 |
if (Iterations > 0 && count > Iterations) |
| 57 |
{
|
| 58 |
Stop(); |
| 59 |
} |
| 60 |
} |
| 61 |
catch (Exception ex) |
| 62 |
{
|
| 63 |
Exception = ex; |
| 64 |
if (!continueOnError) |
| 65 |
{
|
| 66 |
Stop(); |
| 67 |
} |
| 68 |
} |
| 69 |
}, null, DueTime, Interval); |
| 70 |
} |
| 71 |
|
| 72 |
|
| 73 |
public virtual void Stop() |
| 74 |
{
|
| 75 |
if (Active) |
| 76 |
{
|
| 77 |
lock (Lock) |
| 78 |
{
|
| 79 |
if (Active) |
| 80 |
{
|
| 81 |
Active = false; |
| 82 |
Timer.Change(-1, -1); |
| 83 |
OnStopped(EventArgs.Empty); |
| 84 |
if (AsyncResult != null) |
| 85 |
{
|
| 86 |
AsyncResult.Signal(); |
| 87 |
} |
| 88 |
} |
| 89 |
} |
| 90 |
} |
| 91 |
} |
| 92 |
|
| 93 |
public virtual void Start() |
| 94 |
{
|
| 95 |
if (!Active) |
| 96 |
{
|
| 97 |
lock (Lock) |
| 98 |
{
|
| 99 |
if (!Active) |
| 100 |
{
|
| 101 |
Active = true; |
| 102 |
if (Timer != null) |
| 103 |
{
|
| 104 |
Timer.Change(DueTime, Interval); |
| 105 |
} |
| 106 |
else |
| 107 |
{
|
| 108 |
Start(ContinueOnError); |
| 109 |
} |
| 110 |
} |
| 111 |
} |
| 112 |
} |
| 113 |
} |
| 114 |
|
| 115 |
public virtual void Start(TimeSpan dueTime, TimeSpan interval) |
| 116 |
{
|
| 117 |
if (!Active) |
| 118 |
{
|
| 119 |
lock (Lock) |
| 120 |
{
|
| 121 |
if (!Active) |
| 122 |
{
|
| 123 |
DueTime = dueTime; |
| 124 |
Interval = interval; |
| 125 |
Timer.Change(DueTime, Interval); |
| 126 |
} |
| 127 |
} |
| 128 |
} |
| 129 |
} |
| 130 |
protected virtual void OnStopped(EventArgs e) |
| 131 |
{
|
| 132 |
if (Stopped != null) |
| 133 |
{
|
| 134 |
Stopped(this, e); |
| 135 |
} |
| 136 |
} |
| 137 |
|
| 138 |
public virtual void Dispose() |
| 139 |
{
|
| 140 |
Stop(); |
| 141 |
Timer.Dispose(); |
| 142 |
} |
| 143 |
} |
| 144 |
|
| 145 |
#if !SILVERLIGHT |
| 146 |
[Serializable] |
| 147 |
#endif |
| 148 |
public class TimedTask<T> : TimedTask, ITimedTask<T> |
| 149 |
{
|
| 150 |
public TimedTask(TimeSpan due, |
| 151 |
TimeSpan interval, |
| 152 |
int iterations, |
| 153 |
bool continueOnError, |
| 154 |
Action<bool> action, |
| 155 |
IRateLimitingRule<T> rateLimitingRule) : |
| 156 |
base(due, interval, iterations, action) |
| 157 |
{
|
| 158 |
RateLimitingRule = rateLimitingRule; |
| 159 |
ContinueOnError = continueOnError; |
| 160 |
} |
| 161 |
|
| 162 |
protected override void Start(bool continueOnError) |
| 163 |
{
|
| 164 |
var count = 0; |
| 165 |
Timer = new Timer(state => |
| 166 |
{
|
| 167 |
try |
| 168 |
{
|
| 169 |
//[JD] |
| 170 |
//only allow the task to run once concurrently. |
| 171 |
//if a second task attempts to enter the monitor while |
| 172 |
//the first one is still running, simply drop it |
| 173 |
if (Monitor.TryEnter(Lock)) |
| 174 |
{
|
| 175 |
try |
| 176 |
{
|
| 177 |
#if TRACE |
| 178 |
Trace.WriteLine("Running a periodic task");
|
| 179 |
#endif |
| 180 |
var skip = RateLimitingRule.ShouldSkipForRateLimiting(); |
| 181 |
#if TRACE |
| 182 |
Trace.WriteLine(string.Format("{0} Evaluated rate limiting predicate and result was {1}",
|
| 183 |
DateTime.Now.ToShortTimeString(), |
| 184 |
skip ? "'skip'" : "'don't skip'")); |
| 185 |
#endif |
| 186 |
Action(skip); |
| 187 |
var newInterval = RateLimitingRule.CalculateNewInterval(); |
| 188 |
#if TRACE |
| 189 |
Trace.WriteLine(string.Format("{0} Calculated new interval for throttled task and result was: {1}",
|
| 190 |
DateTime.Now.ToShortTimeString(), |
| 191 |
newInterval.HasValue ? newInterval.Value.ToString() : "'no change'")); |
| 192 |
#endif |
| 193 |
count++; |
| 194 |
|
| 195 |
if (Iterations > 0 && count >= Iterations) |
| 196 |
{
|
| 197 |
Stop(); |
| 198 |
} |
| 199 |
else if (newInterval.HasValue) |
| 200 |
{
|
| 201 |
Timer.Change((int)newInterval.Value.TotalMilliseconds, (int)newInterval.Value.TotalMilliseconds); |
| 202 |
} |
| 203 |
} |
| 204 |
finally |
| 205 |
{
|
| 206 |
Monitor.Exit(Lock); |
| 207 |
} |
| 208 |
} |
| 209 |
else |
| 210 |
{
|
| 211 |
#if TRACE |
| 212 |
Trace.WriteLine("Skipping recurring task because the previous iteration is still active");
|
| 213 |
#endif |
| 214 |
Action(true); |
| 215 |
} |
| 216 |
} |
| 217 |
catch (Exception ex) |
| 218 |
{
|
| 219 |
Exception = ex; |
| 220 |
if (!continueOnError) |
| 221 |
{
|
| 222 |
Stop(); |
| 223 |
} |
| 224 |
} |
| 225 |
}, null, DueTime, Interval); |
| 226 |
} |
| 227 |
|
| 228 |
#region ITimedTask Members |
| 229 |
|
| 230 |
public virtual bool RateLimited |
| 231 |
{
|
| 232 |
get { return RateLimitingRule != null; }
|
| 233 |
} |
| 234 |
|
| 235 |
public IRateLimitingRule<T> RateLimitingRule { get; set; }
|
| 236 |
|
| 237 |
public override void Dispose() |
| 238 |
{
|
| 239 |
base.Dispose(); |
| 240 |
} |
| 241 |
#endregion |
| 242 |
} |
| 243 |
} |