iOS动态性(二)可复用而且高度解耦的用户统计埋点实现

一、常规埋点做法

1)常规页面统计埋点

viewDidAppear:

viewDidDisappear:

@implementation HomeViewController
//...other methods
- (void)viewDidAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[WUserStatistics sendEventToServer:@"PAGE_EVENT_HOME_ENTER"];
}

- (void)viewDidDisappear:(BOOL)animated
{
[super viewDidDisappear:animated];
[WUserStatistics sendEventToServer:@"PAGE_EVENT_HOME_LEAVE"];
}
@end

+[WUserStatistics sendEventToServer:]

不应该保持如此高的耦合度

2)常规交互事件埋点

- (IBAction)onFavBtnPressed:(id)sender
{
[WUserStatistics sendEventToServer:@"CTRL_EVENT_HOME_FAV"];
//...do other things
}

二、Method Swizzling、Hook与代码注入

method_exchangeImplementations

Method Swizzling

@interface WHookUtility : NSObject
+ (void)swizzlingInClass:(Class)cls originalSelector:(SEL)originalSelector swizzledSelector:(SEL)swizzledSelector;
@end

@implementation WHookUtility

+ (void)swizzlingInClass:(Class)cls originalSelector:(SEL)originalSelector swizzledSelector:(SEL)swizzledSelector
{
Class class = cls;
Method originalMethod = class_getInstanceMethod(class, originalSelector);
Method swizzledMethod = class_getInstanceMethod(class, swizzledSelector);

BOOL didAddMethod =
class_addMethod(class,
originalSelector,
method_getImplementation(swizzledMethod),
method_getTypeEncoding(swizzledMethod));

if (didAddMethod) {
class_replaceMethod(class,
swizzledSelector,
method_getImplementation(originalMethod),
method_getTypeEncoding(originalMethod));
} else {
method_exchangeImplementations(originalMethod, swizzledMethod);
}
}
@end

WHookUtility

UIViewController

viewWillAppear:

@implementation UIViewController (userStastistics)
+ (void)load {
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
SEL originalSelector = @selector(viewWillAppear:);
SEL swizzledSelector = @selector(swiz_viewWillAppear:);
[WHookUtility swizzlingInClass:[self class] originalSelector:originalSelector swizzledSelector:swizzledSelector];
});
}
#pragma mark - Method Swizzling
- (void)swiz_viewWillAppear:(BOOL)animated
{
//插入需要执行的代码
NSLog(@"我在viewWillAppear执行前偷偷插入了一段代码");
//不能干扰原来的代码流程，插入代码结束后要让本来该执行的代码继续执行
[self swiz_viewWillAppear:animated];
}
@end

三、基于运行时的埋点方案

HomeViewController

DetailViewController

1)统计两个页面的展示与离开次数

viewWillAppear:

viewWillDisappear:

if-else

- (NSString *)pageEventID:(BOOL)bEnterPage
{
NSString *selfClassName = NSStringFromClass([self class]);
NSString *pageEventID = nil;
if ([selfClassName isEqualToString:@"HomeViewController"]) {
pageEventID = bEnterPage ? @"EVENT_HOME_ENTER_PAGE" : @"EVENT_HOME_LEAVE_PAGE";
} else if ([selfClassName isEqualToString:@"DetailViewController"]) {
pageEventID = bEnterPage ? @"EVENT_DETAIL_ENTER_PAGE" : @"EVENT_DETAIL_LEAVE_PAGE";
}
//else if (<#expression#>)...
}

if

WGlobalUserStatisticsConfig.plist

- (NSString *)pageEventID:(BOOL)bEnterPage
{
NSDictionary *configDict = [self dictionaryFromUserStatisticsConfigPlist];
NSString *selfClassName = NSStringFromClass([self class]);
return configDict[selfClassName][@"PageEventIDs"][bEnterPage ? @"Enter" : @"Leave"];
}

- (NSDictionary *)dictionaryFromUserStatisticsConfigPlist
{
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"WGlobalUserStatisticsConfig" ofType:@"plist"];
NSDictionary *dic = [NSDictionary dictionaryWithContentsOfFile:filePath];
return dic;
}

import

2)统计收藏、分享单击事件的次数

UIControl

UIControl

- (void)sendAction:(SEL)action to:(nullable id)target forEvent:(nullable UIEvent *)event;

@implementation UIControl (userStastistics)

+ (void)load {
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
SEL originalSelector = @selector(sendAction:to:forEvent:);
SEL swizzledSelector = @selector(swiz_sendAction:to:forEvent:);
[WHookUtility swizzlingInClass:[self class] originalSelector:originalSelector swizzledSelector:swizzledSelector];
});
}

#pragma mark - Method Swizzling
- (void)swiz_sendAction:(SEL)action to:(id)target forEvent:(UIEvent *)event;
{
//插入埋点代码
[self performUserStastisticsAction:action to:target forEvent:event];
[self swiz_sendAction:action to:target forEvent:event];
}

- (void)performUserStastisticsAction:(SEL)action to:(id)target forEvent:(UIEvent *)event;
{
NSLog(@"\n***hook success.\n[1]action:%@\n[2]target:%@ \n[3]event:%ld", NSStringFromSelector(action), target, (long)event);
}
@end

target

TouchSet

if-else

NSString *actionString = NSStringFromSelector(action);//获取SEL string
NSString *targetName = NSStringFromClass([target class]);//viewController name
NSDictionary *configDict = [self dictionaryFromUserStatisticsConfigPlist];
eventID = configDict[targetName][@"ControlEventIDs"][actionString];

四、基于单元测试的后期维护

onFavBtnPressed:

onFavouriteBtnPressed:

respondsToSelector:

- (void)testIfUserStatisticsConfigPlistValid
{
NSDictionary *configDict = [self dictionaryFromUserStatisticsConfigPlist];
XCTAssertNotNil(configDict, @"WGlobalUserStatisticsConfig.plist加载失败");

[configDict enumerateKeysAndObjectsUsingBlock:^(NSString *  _Nonnull key, id  _Nonnull obj, BOOL * _Nonnull stop) {
XCTAssert([obj isKindOfClass:[NSDictionary class]], @"plist文件结构可能已经改变，请确认");
NSString *targetPageName = key;
Class pageClass = NSClassFromString(targetPageName);
id pageInstance = [[pageClass alloc] init];

//一个pageDict对应一个页面，存放pageID,所有的action及对应的eventID
NSDictionary *pageDict = (NSDictionary *)obj;

//页面配置信息
NSDictionary *pageEventIDDict = pageDict[@"PageEventIDs"];

//交互配置信息
NSDictionary *controlEventIDDict = pageDict[@"ControlEventIDs"];

XCTAssert(pageEventIDDict, @"plist文件未包含PageID字段或者该字段值为空");
XCTAssert(controlEventIDDict, @"plist文件未包含EventIDs字段或者该字段值为空");

[pageEventIDDict enumerateKeysAndObjectsUsingBlock:^(NSString *  _Nonnull key, id  _Nonnull value, BOOL * _Nonnull stop) {
XCTAssert([value isKindOfClass:[NSString class]], @"plist文件结构可能已经改变，请确认");
XCTAssertNotNil(value, @"EVENT_ID为空，请确认");
}];

[controlEventIDDict enumerateKeysAndObjectsUsingBlock:^(NSString *  _Nonnull key, id  _Nonnull value, BOOL * _Nonnull stop) {
XCTAssert([value isKindOfClass:[NSString class]], @"plist文件结构可能已经改变，请确认");
NSString *actionName = key;
SEL actionSel = NSSelectorFromString(actionName);
XCTAssert([pageInstance respondsToSelector:actionSel], @"代码与plist文件函数不匹配，请确认：-[%@ %@]", targetPageName, actionName);

//EVENT_ID不能为空
XCTAssertNotNil(value, @"EVENT_ID为空，请确认");
}];
}];

}

HomeViewController

onFavBtnPressed:

onMyFavBtnPressed:

-[HomeViewController onFavBtnPressed:]

onFavBtnPressed_UA:

class_copyMethodList

_UA

五、结语