Analytics/SFAnalyticsMultiSampler.m

   1 /*
   2  * Copyright (c) 2017 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #if __OBJC2__
  25
  26 #import "SFAnalyticsMultiSampler+Internal.h"
  27 #import "SFAnalytics+Internal.h"
  28 #import "SFAnalyticsDefines.h"
  29 #import "utilities/debugging.h"
  30 #include <notify.h>
  31 #include <dispatch/dispatch.h>
  32
  33 @implementation SFAnalyticsMultiSampler {
  34     NSTimeInterval _samplingInterval;
  35     dispatch_source_t _timer;
  36     NSString* _name;
  37     MultiSamplerDictionary (^_block)(void);
  38     int _notificationToken;
  39     Class _clientClass;
  40     BOOL _oncePerReport;
  41     BOOL _activeTimer;
  42 }
  43
  44 @synthesize name = _name;
  45 @synthesize samplingInterval = _samplingInterval;
  46 @synthesize oncePerReport = _oncePerReport;
  47
  48 - (instancetype)initWithName:(NSString*)name interval:(NSTimeInterval)interval block:(MultiSamplerDictionary (^)(void))block clientClass:(Class)clientClass
  49 {
  50     if (self = [super init]) {
  51         if (![clientClass isSubclassOfClass:[SFAnalytics class]]) {
  52             secerror("SFAnalyticsSampler created without valid client class (%@)", clientClass);
  53             return nil;
  54         }
  55
  56         if (!name || (interval < 1.0f && interval != SFAnalyticsSamplerIntervalOncePerReport) || !block) {
  57             secerror("SFAnalyticsSampler created without proper data");
  58             return nil;
  59         }
  60
  61         _clientClass = clientClass;
  62         _block = block;
  63         _name = name;
  64         _samplingInterval = interval;
  65         [self newTimer];
  66     }
  67     return self;
  68 }
  69
  70 - (void)newTimer
  71 {
  72     if (_activeTimer) {
  73         [self pauseSampling];
  74     }
  75
  76     _oncePerReport = (_samplingInterval == SFAnalyticsSamplerIntervalOncePerReport);
  77     if (_oncePerReport) {
  78         [self setupOnceTimer];
  79     } else {
  80         [self setupPeriodicTimer];
  81     }
  82 }
  83
  84 - (void)setupOnceTimer
  85 {
  86     __weak __typeof(self) weakSelf = self;
  87     notify_register_dispatch(SFAnalyticsFireSamplersNotification, &_notificationToken, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(int token) {
  88         __strong __typeof(self) strongSelf = weakSelf;
  89         if (!strongSelf) {
  90             secnotice("SFAnalyticsSampler", "sampler went away before we could run its once-per-report block");
  91             notify_cancel(token);
  92             return;
  93         }
  94
  95         MultiSamplerDictionary data = strongSelf->_block();
  96         [data enumerateKeysAndObjectsUsingBlock:^(NSString * _Nonnull key, NSNumber * _Nonnull obj, BOOL * _Nonnull stop) {
  97             [[strongSelf->_clientClass logger] logMetric:obj withName:key oncePerReport:strongSelf->_oncePerReport];
  98         }];
  99     });
 100     _activeTimer = YES;
 101 }
 102
 103 - (void)setupPeriodicTimer
 104 {
 105     _timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0));
 106     dispatch_source_set_timer(_timer, dispatch_walltime(0, _samplingInterval * NSEC_PER_SEC), _samplingInterval * NSEC_PER_SEC, _samplingInterval * NSEC_PER_SEC / 50.0);    // give 2% leeway on timer
 107
 108     __weak __typeof(self) weakSelf = self;
 109     dispatch_source_set_event_handler(_timer, ^{
 110         __strong __typeof(self) strongSelf = weakSelf;
 111         if (!strongSelf) {
 112             secnotice("SFAnalyticsSampler", "sampler went away before we could run its once-per-report block");
 113             return;
 114         }
 115
 116         MultiSamplerDictionary data = strongSelf->_block();
 117         [data enumerateKeysAndObjectsUsingBlock:^(NSString * _Nonnull key, NSNumber * _Nonnull obj, BOOL * _Nonnull stop) {
 118             [[strongSelf->_clientClass logger] logMetric:obj withName:key oncePerReport:strongSelf->_oncePerReport];
 119         }];
 120     });
 121     dispatch_resume(_timer);
 122
 123     _activeTimer = YES;
 124 }
 125
 126 - (void)setSamplingInterval:(NSTimeInterval)interval
 127 {
 128     if (interval < 1.0f && !(interval == SFAnalyticsSamplerIntervalOncePerReport)) {
 129         secerror("SFAnalyticsSampler: interval %f is not supported", interval);
 130         return;
 131     }
 132
 133     _samplingInterval = interval;
 134     [self newTimer];
 135 }
 136
 137 - (NSTimeInterval)samplingInterval {
 138     return _samplingInterval;
 139 }
 140
 141 - (MultiSamplerDictionary)sampleNow
 142 {
 143     MultiSamplerDictionary data = _block();
 144     [data enumerateKeysAndObjectsUsingBlock:^(NSString * _Nonnull key, NSNumber * _Nonnull obj, BOOL * _Nonnull stop) {
 145         [[self->_clientClass logger] logMetric:obj withName:key oncePerReport:self->_oncePerReport];
 146     }];
 147     return data;
 148 }
 149
 150 - (void)pauseSampling
 151 {
 152     if (!_activeTimer) {
 153         return;
 154     }
 155
 156     if (_oncePerReport) {
 157         notify_cancel(_notificationToken);
 158         _notificationToken = 0;
 159     } else {
 160         dispatch_source_cancel(_timer);
 161     }
 162     _activeTimer = NO;
 163 }
 164
 165 - (void)resumeSampling
 166 {
 167     [self newTimer];
 168 }
 169
 170 - (void)dealloc
 171 {
 172     [self pauseSampling];
 173 }
 174
 175 @end
 176
 177 #endif