SRVResolver.h

/*
    File:       SRVResolver.h
 
    Contains:   Uses <dns_sd.h> APIs to resolve SRV records.
 
    Written by: DTS
 
    Copyright:  Copyright (c) 2010-2012 Apple Inc. All Rights Reserved.
 
    Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple Inc.
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*/
 
#import <Foundation/Foundation.h>
 
#include <dns_sd.h>
 
@protocol SRVResolverDelegate;
 
@interface SRVResolver : NSObject
 
- (id)initWithSRVName:(NSString *)srvName;
 
// properties set up by the init method
 
@property (nonatomic, copy,   readonly ) NSString *                 srvName;
 
// properties you can change any time
 
@property (nonatomic, weak,   readwrite) id<SRVResolverDelegate>    delegate;
 
// properties that change as the result of running the query
 
@property (nonatomic, assign, readonly, getter=isFinished) BOOL     finished;   // observable
@property (nonatomic, copy,   readonly ) NSError *                  error;      // observable
@property (nonatomic, copy,   readonly ) NSArray *                  results;    // of NSDictionary, observable
 
// Note that there is no default timeout here.  See "Read Me About SRVResolver" 
// for a discussion as to why not.
 
- (void)start;
- (void)stop;
 
@end
 
// Keys for the dictionaries in the results array:
 
extern NSString * kSRVResolverPriority;     // NSNumber, host byte order
extern NSString * kSRVResolverWeight;       // NSNumber, host byte order
extern NSString * kSRVResolverPort;         // NSNumber, host byte order
extern NSString * kSRVResolverTarget;       // NSString
 
extern NSString * kSRVResolverErrorDomain;
 
@protocol SRVResolverDelegate <NSObject>
 
@optional
 
// These delegates methods are called from the default run loop mode on the run loop of the 
// thread that called -start.
 
- (void)srvResolver:(SRVResolver *)resolver didReceiveResult:(NSDictionary *)result;
    // Called when we've successfully receive an answer.  The result parameter is a copy 
    // of the dictionary that we just added to the results array.  This callback can be 
    // called multiple times if there are multiple results.  You learn that the last 
    // result was delivered by way of the -srvResolver:didStopWithError: callback.
    
- (void)srvResolver:(SRVResolver *)resolver didStopWithError:(NSError *)error;
    // Called when the query stops (except when you stop it yourself by calling -stop), 
    // either because it's received all the results (error is nil) or there's been an 
    // error (error is not nil).
 
@end