Sync iPhone AddressBook with a Backend Server - ios

Question

There are lots of applications doing AddressBook synchronization with their Backend servers to cross check which contacts in your AddressBook are using their application and which users needs to be invited to their application.
For the first time it may do a full sync, but after that it shouldn't be a full sync.
My first question is, What is the best way to sync the full AddressBook with a Backend Server?
Second question is, How to sync ONLY the contacts which has modified recently?
If there's any sample application or a tutorial please share with me.
Thanks in advance.

Answer 1

Hello i am also working on same concept.
First of all i don’t have any tutorial to share with you. But what i am doing in application i am sharing with you entire flow.
When application runs first time i am fetching all the contact numbers and sending to server.
But when any contact modifies i am sending modified contact number only.
You will get a call back from address book when contact is modified. There will be specific record id for each contact
Swift
typealias ABExternalChangeCallback = CFunctionPointer<((ABAddressBook!, CFDictionary!,UnsafeMutablePointer) -> Void)>
From this property you will come to know when your contact was modified recently.
ABRecordCopyValue(record, kABPersonModificationDateProperty).takeRetainedValue() as? NSDate
So either way you can check for contact numbers which were modified recently and then again just send those contact to server.
I hope it may helps you!.
Thanks

Answer 2

Get All Phone number from address book as formatted string and post this string to web-server. this make easy to sent all contact at small delay. at web-server side you can code to split phone number to separate number and check for user with same number.
-(NSString *)getPhoneContactAsSingleString
{
NSString *numberString=[NSString new];
numberString=#"";
CFErrorRef *error = nil;
ABAddressBookRef addressBook = ABAddressBookCreateWithOptions(NULL, error);
__block BOOL accessGranted = NO;
if (ABAddressBookRequestAccessWithCompletion != NULL) { // we're on iOS 6
dispatch_semaphore_t sema = dispatch_semaphore_create(0);
ABAddressBookRequestAccessWithCompletion(addressBook, ^(bool granted, CFErrorRef error) {
accessGranted = granted;
dispatch_semaphore_signal(sema);
});
dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
}
else { // we're on iOS 5 or older
accessGranted = YES;
}
if (accessGranted) {
#ifdef DEBUG
//NSLog(#"Fetching contact");
#endif
NSMutableArray *contacts=[[NSMutableArray alloc]init];
NSMutableDictionary *numberNameDictionary=[[NSMutableDictionary alloc]init];
ABAddressBookRef addressBook = ABAddressBookCreateWithOptions(NULL, error);
CFArrayRef allPeople = ABAddressBookCopyArrayOfAllPeople(addressBook);
CFIndex nPeople = CFArrayGetCount(allPeople);
for (int i = 0; i < nPeople; i++)
{
NSMutableDictionary *dictionary=[[NSMutableDictionary alloc]init];
ABRecordRef person = CFArrayGetValueAtIndex(allPeople, i);
if (person) {
NSString *firstname=[NSString new];
NSString *lastname =[NSString new];
CFStringRef firstnameStringRef=ABRecordCopyValue(person, kABPersonFirstNameProperty);
CFStringRef lastnameStringRef=ABRecordCopyValue(person, kABPersonLastNameProperty);
if (firstnameStringRef) {
firstname=[NSString stringWithFormat:#"%#",firstnameStringRef];
}
if (lastnameStringRef) {
lastname =[NSString stringWithFormat:#"%#",lastnameStringRef];
}
NSString *name=[NSString new];
if (firstname.length!=0)
{
name=firstname;
if (lastname.length!=0) {
name=[name stringByAppendingString:#" "];
name=[name stringByAppendingString:lastname];
}
}
NSMutableArray *phoneNumbers = [[NSMutableArray alloc] init];
ABMultiValueRef multiPhones = ABRecordCopyValue(person, kABPersonPhoneProperty);
for(CFIndex i=0;i<ABMultiValueGetCount(multiPhones);i++) {
CFStringRef phoneNumberRef = ABMultiValueCopyValueAtIndex(multiPhones, i);
NSString *phoneNumber = (__bridge NSString *) phoneNumberRef;
NSString *braketStripedNum = [phoneNumber stringByReplacingOccurrencesOfString:#"(" withString:#""];
braketStripedNum = [braketStripedNum stringByReplacingOccurrencesOfString:#")" withString:#""];
phoneNumber=braketStripedNum;
NSString *dashStripedNum = [self clean_phonenumber:phoneNumber with_string:#"-"];
phoneNumber=dashStripedNum;
NSString *comaStripedNum = [self clean_phonenumber:phoneNumber with_string:#","];
phoneNumber=comaStripedNum;
NSString *dotStripedNum = [self clean_phonenumber:phoneNumber with_string:#"."];
phoneNumber=dotStripedNum;
NSString *spaceStripedNum = [self clean_phonenumber:phoneNumber with_string:#" "];
phoneNumber=spaceStripedNum;
if (phoneNumber.length>10) {
phoneNumber=[phoneNumber substringFromIndex:phoneNumber.length-10];
}
if(phoneNumber.length!=0){
[phoneNumbers addObject:phoneNumber];
[numberNameDictionary setObject:name forKey:phoneNumber];
//NSLog(#"[%#] --> [%#]",orginal_phonenumber,phoneNumber);
numberString=[NSString stringWithFormat:#"%#%#,",numberString,phoneNumber];
}
}
//NSLog(#"%#",phoneNumbers);
if (phoneNumbers.count!=0) {
[dictionary setObject:name forKey:#"name"];
[dictionary setObject:phoneNumbers forKey:#"phonenumbers"];
[contacts addObject:dictionary];
}
}
}
if (numberString.length!=0) {
numberString=[numberString substringToIndex:[numberString length]-1];
}
}
else
{
#ifdef DEBUG
NSLog(#"Cannot fetch Contacts :( ");
#endif
}
return numberString;
}
Clean phone numbers
-(NSString *)clean_phonenumber:(NSString *)number with_string:(NSString *)string
{
NSArray *numberStrips = [number componentsSeparatedByString:string];
NSString *cleanNumber = #"";
for (NSString *eachString in numberStrips) {
cleanNumber = [NSString stringWithFormat:#"%#%#", cleanNumber, eachString];
}
return cleanNumber;
}
Just Check the method
NSLog(#"%#",[self getPhoneContactAsSingleString]);