WebRTC iOS平台的基本实现

Posted 2020-08-09

前面介绍了如何下载编译WebRTC，现在介绍如何利用WebRTC在ios客户端上简单实现音视频通话。

对下载编译还有问题的，请先查看：WebRTC(iOS)下载编译。

不需要下载源码只需要库文件的也可以用CocoaPods下载编译好的库：pod ‘libjingle_peerconnection‘

开始编写之前，我们首先要搭建一个服务器，此服务器主要用于信令交互。我们这里采用github上的开源项目：SkyRTC项目。

完整Demo下载：FLWebRTCDemo。

开始iOS客户端的实现：

1、引入编译出的WebRTC库文件

2、引入必要的依赖库

AudioToolbox.framework

VideoToolbox.framework

QuartzCore.framework

OpenGLES.framework

CoreGraphics.framework

CoreVideo.framework

CoreMedia.framework

CoreAudio.framework

AVFoundation.framework

GLKit.framework

CFNetwork.framework

Security.framework

libsqlite3.tbd

libicucore.tbd

libc.tbd

libstdc++.6.0.9.tbd

3、代码实现音视频通话

//
	// WebRTCHelper.h
	// WebRTCDemo
	//
	#import <Foundation/Foundation.h>
	#import <SocketRocket.h>
	#import "RTCMediaStream.h"
	#import "RTCPeerConnectionFactory.h"
	#import "RTCPeerConnection.h"
	#import "RTCPair.h"
	#import "RTCMediaConstraints.h"
	#import "RTCAudioTrack.h"
	#import "RTCVideoTrack.h"
	#import "RTCVideoCapturer.h"
	#import "RTCSessionDescription.h"
	#import "RTCSessionDescriptionDelegate.h"
	#import "RTCEAGLVideoView.h"
	#import "RTCICEServer.h"
	#import "RTCVideoSource.h"
	#import "RTCAVFoundationVideoSource.h"
	#import "RTCICECandidate.h"
	@protocol WebRTCHelperDelegate;
	@interface WebRTCHelper : NSObject<SRWebSocketDelegate>
	@property (nonatomic, assign)id<WebRTCHelperDelegate> delegate;
	/**
	* 与服务器建立连接
	*
	* @param server 服务器地址
	* @param room 房间号
	*/
	- (void)connectServer:(NSString *)server room:(NSString *)room;
	/**
	* 退出房间
	*/
	- (void)exitRoom;
	@end
	@protocol WebRTCHelperDelegate <NSObject>
	@optional
	- (void)webRTCHelper:(WebRTCHelper *)webRTChelper setLocalStream:(RTCMediaStream *)stream userId:(NSString *)userId;
	- (void)webRTCHelper:(WebRTCHelper *)webRTChelper addRemoteStream:(RTCMediaStream *)stream userId:(NSString *)userId;
	- (void)webRTCHelper:(WebRTCHelper *)webRTChelper closeWithUserId:(NSString *)userId;
	@end

 

 

//
	// WebRTCHelper.m
	// WebRTCDemo
	//
	#import "WebRTCHelper.h"
	#import <UIKit/UIKit.h>
	#import <AVFoundation/AVFoundation.h>
	typedef enum : NSUInteger {
	RoleCaller,
	RoleCallee,
	} Role;
	@interface WebRTCHelper ()<RTCPeerConnectionDelegate, RTCSessionDescriptionDelegate>
	@end
	@implementation WebRTCHelper
	{
	SRWebSocket *_socket;
	NSString *_server;
	NSString *_room;
	RTCPeerConnectionFactory *_factory;
	RTCMediaStream *_localStream;
	NSString *_myId;
	NSMutableDictionary *_connectionDic;
	NSMutableArray *_connectionIdArray;
	NSString *_currentId;
	Role _role;
	}
	- (instancetype)init
	{
	self = [super init];
	if (self)
	{
	_connectionDic = [NSMutableDictionary dictionary];
	_connectionIdArray = [NSMutableArray array];
	}
	return self;
	}
	/**
	* 与服务器建立连接
	*
	* @param server 服务器地址
	* @param room 房间号
	*/
	- (void)connectServer:(NSString *)server room:(NSString *)room
	{
	_server = server;
	_room = room;
	NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"ws://%@:3000",server]] cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10];
	_socket = [[SRWebSocket alloc] initWithURLRequest:request];
	_socket.delegate = self;
	[_socket open];
	}
	/**
	* 加入房间
	*
	* @param room 房间号
	*/
	- (void)joinRoom:(NSString *)room
	{
	if (_socket.readyState == SR_OPEN)
	{
	NSDictionary *dic = @{@"eventName": @"__join", @"data": @{@"room": room}};
	NSData *data = [NSJSONSerialization dataWithJSONObject:dic options:NSJSONWritingPrettyPrinted error:nil];
	[_socket send:data];
	}
	}
	/**
	* 退出房间
	*/
	- (void)exitRoom
	{
	_localStream = nil;
	[_connectionIdArray enumerateObjectsUsingBlock:^(NSString *obj, NSUInteger idx, BOOL * _Nonnull stop) {
	[self closePeerConnection:obj];
	}];
	[_socket close];
	}
	/**
	* 关闭peerConnection
	*
	* @param connectionId <#connectionId description#>
	*/
	- (void)closePeerConnection:(NSString *)connectionId
	{
	RTCPeerConnection *peerConnection = [_connectionDic objectForKey:connectionId];
	if (peerConnection)
	{
	[peerConnection close];
	}
	[_connectionIdArray removeObject:connectionId];
	[_connectionDic removeObjectForKey:connectionId];
	dispatch_async(dispatch_get_main_queue(), ^{
	if ([_delegate respondsToSelector:@selector(webRTCHelper:closeWithUserId:)])
	{
	[_delegate webRTCHelper:self closeWithUserId:connectionId];
	}
	});
	}
	/**
	* 创建本地流
	*/
	- (void)createLocalStream
	{
	_localStream = [_factory mediaStreamWithLabel:@"ARDAMS"];
	//音频
	RTCAudioTrack *audioTrack = [_factory audioTrackWithID:@"ARDAMSa0"];
	[_localStream addAudioTrack:audioTrack];
	//视频
	NSArray *deviceArray = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
	AVCaptureDevice *device = [deviceArray lastObject];
	//检测摄像头权限
	AVAuthorizationStatus authStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];
	if(authStatus == AVAuthorizationStatusRestricted || authStatus == AVAuthorizationStatusDenied)
	{
	NSLog(@"相机访问受限");
	if ([_delegate respondsToSelector:@selector(webRTCHelper:setLocalStream:userId:)])
	{
	[_delegate webRTCHelper:self setLocalStream:nil userId:_myId];
	}
	}
	else
	{
	if (device)
	{
	RTCVideoCapturer *capturer = [RTCVideoCapturer capturerWithDeviceName:device.localizedName];
	RTCVideoSource *videoSource = [_factory videoSourceWithCapturer:capturer constraints:[self localVideoConstraints]];
	RTCVideoTrack *videoTrack = [_factory videoTrackWithID:@"ARDAMSv0" source:videoSource];
	[_localStream addVideoTrack:videoTrack];
	if ([_delegate respondsToSelector:@selector(webRTCHelper:setLocalStream:userId:)])
	{
	[_delegate webRTCHelper:self setLocalStream:_localStream userId:_myId];
	}
	}
	else
	{
	NSLog(@"该设备不能打开摄像头");
	if ([_delegate respondsToSelector:@selector(webRTCHelper:setLocalStream:userId:)])
	{
	[_delegate webRTCHelper:self setLocalStream:nil userId:_myId];
	}
	}
	}
	}
	/**
	* 视频的相关约束
	*/
	- (RTCMediaConstraints *)localVideoConstraints
	{
	RTCPair *maxWidth = [[RTCPair alloc] initWithKey:@"maxWidth" value:@"640"];
	RTCPair *minWidth = [[RTCPair alloc] initWithKey:@"minWidth" value:@"640"];
	RTCPair *maxHeight = [[RTCPair alloc] initWithKey:@"maxHeight" value:@"480"];
	RTCPair *minHeight = [[RTCPair alloc] initWithKey:@"minHeight" value:@"480"];
	RTCPair *minFrameRate = [[RTCPair alloc] initWithKey:@"minFrameRate" value:@"15"];
	NSArray *mandatory = @[maxWidth, minWidth, maxHeight, minHeight, minFrameRate];
	RTCMediaConstraints *constraints = [[RTCMediaConstraints alloc] initWithMandatoryConstraints:mandatory optionalConstraints:nil];
	return constraints;
	}
	/**
	* 为所有连接创建offer
	*/
	- (void)createOffers
	{
	[_connectionDic enumerateKeysAndObjectsUsingBlock:^(NSString *key, RTCPeerConnection *obj, BOOL * _Nonnull stop) {
	_currentId = key;
	_role = RoleCaller;
	[obj createOfferWithDelegate:self constraints:[self offerOranswerConstraint]];
	}];
	}
	/**
	* 为所有连接添加流
	*/
	- (void)addStreams
	{
	[_connectionDic enumerateKeysAndObjectsUsingBlock:^(NSString *key, RTCPeerConnection *obj, BOOL * _Nonnull stop) {
	if (!_localStream)
	{
	[self createLocalStream];
	}
	[obj addStream:_localStream];
	}];
	}
	/**
	* 创建所有连接
	*/
	- (void)createPeerConnections
	{
	[_connectionIdArray enumerateObjectsUsingBlock:^(NSString *obj, NSUInteger idx, BOOL * _Nonnull stop) {
	RTCPeerConnection *connection = [self createPeerConnection:obj];
	[_connectionDic setObject:connection forKey:obj];
	}];
	}
	/**
	* 创建点对点连接
	*
	* @param connectionId <#connectionId description#>
	*
	* @return <#return value description#>
	*/
	- (RTCPeerConnection *)createPeerConnection:(NSString *)connectionId
	{
	if (!_factory)
	{
	[RTCPeerConnectionFactory initializeSSL];
	_factory = [[RTCPeerConnectionFactory alloc] init];
	}
	RTCPeerConnection *connection = [_factory peerConnectionWithICEServers:nil constraints:[self peerConnectionConstraints] delegate:self];
	return connection;
	}
	/**
	* peerConnection约束
	*
	* @return <#return value description#>
	*/
	- (RTCMediaConstraints *)peerConnectionConstraints
	{
	RTCMediaConstraints *constraints = [[RTCMediaConstraints alloc] initWithMandatoryConstraints:nil optionalConstraints:@[[[RTCPair alloc] initWithKey:@"DtlsSrtpKeyAgreement" value:@"true"]]];
	return constraints;
	}
	/**
	* 设置offer/answer的约束
	*/
	- (RTCMediaConstraints *)offerOranswerConstraint
	{
	NSMutableArray *array = [NSMutableArray array];
	RTCPair *receiveAudio = [[RTCPair alloc] initWithKey:@"OfferToReceiveAudio" value:@"true"];
	[array addObject:receiveAudio];
	NSString *video = @"true";
	RTCPair *receiveVideo = [[RTCPair alloc] initWithKey:@"OfferToReceiveVideo" value:video];
	[array addObject:receiveVideo];
	RTCMediaConstraints *constraints = [[RTCMediaConstraints alloc] initWithMandatoryConstraints:array optionalConstraints:nil];
	return constraints;
	}
	#pragma mark--RTCSessionDescriptionDelegate
	// Called when creating a session.
	- (void)peerConnection:(RTCPeerConnection *)peerConnection
	didCreateSessionDescription:(RTCSessionDescription *)sdp
	error:(NSError *)error
	{
	NSLog(@"%s",__func__);
	[peerConnection setLocalDescriptionWithDelegate:self sessionDescription:sdp];
	}
	// Called when setting a local or remote description.
	- (void)peerConnection:(RTCPeerConnection *)peerConnection
	didSetSessionDescriptionWithError:(NSError *)error
	{
	NSLog(@"%s",__func__);
	if (peerConnection.signalingState == RTCSignalingHaveRemoteOffer)
	{
	[peerConnection createAnswerWithDelegate:self constraints:[self offerOranswerConstraint]];
	}
	else if (peerConnection.signalingState == RTCSignalingHaveLocalOffer)
	{
	if (_role == RoleCallee)
	{
	NSDictionary *dic = @{@"eventName": @"__answer", @"data": @{@"sdp": @{@"type": @"answer", @"sdp": peerConnection.localDescription.description}, @"socketId": _currentId}};
	NSData *data = [NSJSONSerialization dataWithJSONObject:dic options:NSJSONWritingPrettyPrinted error:nil];
	[_socket send:data];
	}
	else if(_role == RoleCaller)
	{
	NSDictionary *dic = @{@"eventName": @"__offer", @"data": @{@"sdp": @{@"type": @"offer", @"sdp": peerConnection.localDescription.description}, @"socketId": _currentId}};
	NSData *data = [NSJSONSerialization dataWithJSONObject:dic options:NSJSONWritingPrettyPrinted error:nil];
	[_socket send:data];
	}
	}
	else if (peerConnection.signalingState == RTCSignalingStable)
	{
	if (_role == RoleCallee)
	{
	NSDictionary *dic = @{@"eventName": @"__answer", @"data": @{@"sdp": @{@"type": @"answer", @"sdp": peerConnection.localDescription.description}, @"socketId": _currentId}};
	NSData *data = [NSJSONSerialization dataWithJSONObject:dic options:NSJSONWritingPrettyPrinted error:nil];
	[_socket send:data];
	}
	}
	}
	#pragma mark--RTCPeerConnectionDelegate
	// Triggered when the SignalingState changed.
	- (void)peerConnection:(RTCPeerConnection *)peerConnection
	signalingStateChanged:(RTCSignalingState)stateChanged
	{
	NSLog(@"%s",__func__);
	NSLog(@"%d", stateChanged);
	}
	// Triggered when media is received on a new stream from remote peer.
	- (void)peerConnection:(RTCPeerConnection *)peerConnection
	addedStream:(RTCMediaStream *)stream
	{
	NSLog(@"%s",__func__);
	dispatch_async(dispatch_get_main_queue(), ^{
	if ([_delegate respondsToSelector:@selector(webRTCHelper:addRemoteStream:userId:)])
	{
	[_delegate webRTCHelper:self addRemoteStream:stream userId:_currentId];
	}
	});
	}
	// Triggered when a remote peer close a stream.
	- (void)peerConnection:(RTCPeerConnection *)peerConnection
	removedStream:(RTCMediaStream *)stream
	{
	NSLog(@"%s",__func__);
	}
	// Triggered when renegotiation is needed, for example the ICE has restarted.
	- (void)peerConnectionOnRenegotiationNeeded:(RTCPeerConnection *)peerConnection
	{
	NSLog(@"%s",__func__);
	}
	// Called any time the ICEConnectionState changes.
	- (void)peerConnection:(RTCPeerConnection *)peerConnection
	iceConnectionChanged:(RTCICEConnectionState)newState
	{
	NSLog(@"%s",__func__);
	NSLog(@"%d", newState);
	}
	// Called any time the ICEGatheringState changes.
	- (void)peerConnection:(RTCPeerConnection *)peerConnection
	iceGatheringChanged:(RTCICEGatheringState)newState
	{
	NSLog(@"%s",__func__);
	NSLog(@"%d", newState);
	}
	// New Ice candidate have been found.
	- (void)peerConnection:(RTCPeerConnection *)peerConnection
	gotICECandidate:(RTCICECandidate *)candidate
	{
	NSLog(@"%s",__func__);
	NSDictionary *dic = @{@"eventName": @"__ice_candidate", @"data": @{@"label": [NSNumber numberWithInteger:candidate.sdpMLineIndex], @"candidate": candidate.sdp, @"socketId": _currentId}};
	NSData *data = [NSJSONSerialization dataWithJSONObject:dic options:NSJSONWritingPrettyPrinted error:nil];
	[_socket send:data];
	}
	// New data channel has been opened.
	- (void)peerConnection:(RTCPeerConnection*)peerConnection didOpenDataChannel:(RTCDataChannel*)dataChannel
	{
	NSLog(@"%s",__func__);
	}
	#pragma mark--SRWebSocketDelegate
	- (void)webSocket:(SRWebSocket *)webSocket didReceiveMessage:(id)message
	{
	NSLog(@"收到服务器消息:%@",message);
	NSDictionary *dic = [NSJSONSerialization JSONObjectWithData:[message dataUsingEncoding:NSUTF8StringEncoding] options:NSJSONReadingMutableContainers error:nil];
	NSString *eventName = dic[@"eventName"];
	if ([eventName isEqualToString:@"_peers"])
	{
	NSDictionary *dataDic = dic[@"data"];
	NSArray *connections = dataDic[@"connections"];
	[_connectionIdArray addObjectsFromArray:connections];
	_myId = dataDic[@"you"];
	if (!_factory)
	{
	[RTCPeerConnectionFactory initializeSSL];
	_factory = [[RTCPeerConnectionFactory alloc] init];
	}
	if (!_localStream)
	{
	[self createLocalStream];
	}
	[self createPeerConnections];
	[self addStreams];
	[self createOffers];
	}
	else if ([eventName isEqualToString:@"_ice_candidate"])
	{
	NSDictionary *dataDic = dic[@"data"];
	NSString *socketId = dataDic[@"socketId"];
	NSInteger sdpMLineIndex = [dataDic[@"label"] integerValue];
	NSString *sdp = dataDic[@"candidate"];
	RTCICECandidate *candidate = [[RTCICECandidate alloc] initWithMid:nil index:sdpMLineIndex sdp:sdp];
	RTCPeerConnection *peerConnection = [_connectionDic objectForKey:socketId];
	[peerConnection addICECandidate:candidate];
	}
	else if ([eventName isEqualToString:@"_new_peer"])
	{
	NSDictionary *dataDic = dic[@"data"];
	NSString *socketId = dataDic[@"socketId"];
	RTCPeerConnection *peerConnection = [self createPeerConnection:socketId];
	if (!_localStream)
	{
	[self createLocalStream];
	}
	[peerConnection addStream:_localStream];
	[_connectionIdArray addObject:socketId];
	[_connectionDic setObject:peerConnection forKey:socketId];
	}
	else if ([eventName isEqualToString:@"_remove_peer"])
	{
	NSDictionary *dataDic = dic[@"data"];
	NSString *socketId = dataDic[@"socketId"];
	[self closePeerConnection:socketId];
	}
	else if ([eventName isEqualToString:@"_offer"])
	{
	NSDictionary *dataDic = dic[@"data"];
	NSDictionary *sdpDic = dataDic[@"sdp"];
	NSString *sdp = sdpDic[@"sdp"];
	NSString *type = sdpDic[@"type"];
	NSString *socketId = dataDic[@"socketId"];
	RTCPeerConnection *peerConnection = [_connectionDic objectForKey:socketId];
	RTCSessionDescription *remoteSdp = [[RTCSessionDescription alloc] initWithType:type sdp:sdp];
	[peerConnection setRemoteDescriptionWithDelegate:self sessionDescription:remoteSdp];
	_currentId = socketId;
	_role = RoleCallee;
	}
	else if ([eventName isEqualToString:@"_answer"])
	{
	NSDictionary *dataDic = dic[@"data"];
	NSDictionary *sdpDic = dataDic[@"sdp"];
	NSString *sdp = sdpDic[@"sdp"];
	NSString *type = sdpDic[@"type"];
	NSString *socketId = dataDic[@"socketId"];
	RTCPeerConnection *peerConnection = [_connectionDic objectForKey:socketId];
	RTCSessionDescription *remoteSdp = [[RTCSessionDescription alloc] initWithType:type sdp:sdp];
	[peerConnection setRemoteDescriptionWithDelegate:self sessionDescription:remoteSdp];
	}
	}
	- (void)webSocketDidOpen:(SRWebSocket *)webSocket
	{
	NSLog(@"websocket建立成功");
	[self joinRoom:_room];
	}
	- (void)webSocket:(SRWebSocket *)webSocket didFailWithError:(NSError *)error
	{
	NSLog(@"%s",__func__);
	NSLog(@"%ld:%@",(long)error.code, error.localizedDescription);
	// [[[UIAlertView alloc] initWithTitle:@"提示" message:[NSString stringWithFormat:@"%ld:%@",(long)error.code, error.localizedDescription] delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil, nil] show];
	}
	- (void)webSocket:(SRWebSocket *)webSocket didCloseWithCode:(NSInteger)code reason:(NSString *)reason wasClean:(BOOL)wasClean
	{
	NSLog(@"%s",__func__);
	NSLog(@"%ld:%@",(long)code, reason);
	// [[[UIAlertView alloc] initWithTitle:@"提示" message:[NSString stringWithFormat:@"%ld:%@",(long)code, reason] delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil, nil] show];
	}
	@end