Swift 2.1 Searching Contacts by E-mail in iOS 9 - swift2

Question

In the new Contacts framework there appears to be a way to search by name:
let predicate = CNContact.predicateForContactsMatchingName("john")
let toFetch = [CNContactGivenNameKey, CNContactFamilyNameKey]
do {
let contacts = try store.unifiedContactsMatchingPredicate(
predicate, keysToFetch: toFetch)
for contact in contacts{
print(contact.givenName)
print(contact.familyName)
print(contact.identifier)
}
}
catch let err {
print(err)
}
But no apparent way to search by e-mail that I can find in the documentation or searches.
How do I search contacts by e-mail address?
These articles here and here have been helpful in learning the new framework but neither of these have revealed how to search by e-mail.

Answer 1

Having the same problem, I managed to find a solution. I have solved this by fetching all the contacts and then iterating over them to find matching contacts.
The code can surely be refactored.
import UIKit
import Contacts
public class ContactFinder: NSObject {
private lazy var store = CNContactStore()
private var allContacts: [CNContact] = []
private let keysToFetch: [CNKeyDescriptor] = [CNContactEmailAddressesKey, CNContactPhoneNumbersKey, CNContactFamilyNameKey, CNContactGivenNameKey, CNContactPostalAddressesKey, CNContactBirthdayKey, CNContactImageDataKey, CNContactImageDataAvailableKey]
public func requestAccess(completion:((success: Bool, error: NSError?)->())) {
let status = CNContactStore.authorizationStatusForEntityType(.Contacts)
if status == .NotDetermined {
store.requestAccessForEntityType(.Contacts, completionHandler: { [weak self](success, error) -> Void in
if success {
self?.getAllContacts(completion)
} else {
completion(success: false, error: error)
}
})
} else if status == .Authorized {
getAllContacts(completion)
} else {
completion(success: false, error: nil)
}
}
public func searchForContactUsingEmail(email: String, completion:((contacts: [CNContact])->())) {
var contacts: [CNContact] = []
for contact in allContacts {
let em = contact.emailAddresses
if em.count > 0 {
let results = em.filter({ val in
let ce = (val.value as! String).trimmedString.lowercaseString
return ce == email.trimmedString.lowercaseString
})
if results.count > 0 {
contacts.append(contact)
}
}
}
completion(contacts: contacts)
}
private func getAllContacts(completion:((success: Bool, error: NSError?)->())) {
let request = CNContactFetchRequest(keysToFetch: keysToFetch)
request.predicate = nil
request.unifyResults = true
do {
try store.enumerateContactsWithFetchRequest(request, usingBlock: { [weak self](contact, _) -> Void in
self?.allContacts.append(contact)
})
} catch let e as NSError {
print(e.localizedDescription)
completion(success: false, error: e)
return
}
completion(success: true, error: nil)
}
}