Introduced Persistent Storage Injection for Queue

Updated Code & Example

Added basic Queue tests

README updated accordingly

Author: gelosi

EDQueue.podspec

@@ -1,11 +1,11 @@
 Pod::Spec.new do |s|
   s.name         = 'EDQueue'
-  s.version      = '0.7.2'
+  s.version      = '0.7.3'
   s.license      = 'MIT'
   s.summary      = 'A persistent background job queue for iOS.'
   s.homepage     = 'https://github.com/gelosi/queue'
   s.authors      = {'Andrew Sliwinski' => '[email protected]', 'Francois Lambert' => '[email protected]', 'Oleg Shanyuk' => '[email protected]'}
-  s.source       = { :git => 'https://github.com/gelosi/queue.git', :tag => 'v0.7.2' }
+  s.source       = { :git => 'https://github.com/gelosi/queue.git', :tag => 'v0.7.3' }
   s.platform     = :ios, '7.0'
   s.source_files = 'EDQueue'
   s.library      = 'sqlite3.0'

EDQueue/EDQueue.h

@@ -6,9 +6,10 @@
 //  Copyright (c) 2012 Andrew Sliwinski. All rights reserved.
 //
 
-#import <Foundation/Foundation.h>
+@import Foundation;
 
 #import "EDQueueJob.h"
+#import "EDQueuePersistentStorageProtocol.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -26,22 +27,32 @@ extern NSString *const EDQueueJobDidSucceed;
 extern NSString *const EDQueueJobDidFail;
 extern NSString *const EDQueueDidDrain;
 
-extern NSString *const EDQueueNameKey;
-extern NSString *const EDQueueDataKey;
+@class EDQueue;
 
-
-@protocol EDQueueDelegate;
+@protocol EDQueueDelegate <NSObject>
+- (void)queue:(EDQueue *)queue processJob:(EDQueueJob *)job completion:(EDQueueCompletionBlock)block;
+@end
 
 @interface EDQueue : NSObject
 
-+ (EDQueue *)sharedInstance;
-
 @property (nonatomic, weak) id<EDQueueDelegate> delegate;
+@property (nonatomic, strong, readonly) id<EDQueuePersistentStorage> storage;
 
+/**
+ * Returns true if Queue is running (e.g. not stopped).
+ */
 @property (nonatomic, readonly) BOOL isRunning;
+/**
+ * Returns true if Queue is performing Job right now
+ */
 @property (nonatomic, readonly) BOOL isActive;
+/**
+ * Retry limit for failing tasks (will be elimitated and moved to Job later)
+ */
 @property (nonatomic) NSUInteger retryLimit;
 
+- (instancetype)initWithPersistentStore:(id<EDQueuePersistentStorage>)persistentStore;
+
 - (void)enqueueJob:(EDQueueJob *)job;
 - (void)start;
 - (void)stop;
@@ -53,8 +64,5 @@ extern NSString *const EDQueueDataKey;
 
 @end
 
-@protocol EDQueueDelegate <NSObject>
-- (void)queue:(EDQueue *)queue processJob:(EDQueueJob *)job completion:(EDQueueCompletionBlock)block;
-@end
 
 NS_ASSUME_NONNULL_END

EDQueue/EDQueue.m

@@ -15,68 +15,31 @@
 NSString *const EDQueueJobDidFail = @"EDQueueJobDidFail";
 NSString *const EDQueueDidDrain = @"EDQueueDidDrain";
 
-NSString *const EDQueueNameKey = @"name";
-NSString *const EDQueueDataKey = @"data";
-
-
-NSString *const EDQueueStorageJobIdKey = @"id";
-NSString *const EDQueueStorageJobTaskKey = @"task";
-NSString *const EDQueueStorageJobDataKey = @"data";
-NSString *const EDQueueStorageJobAttemptsKey = @"atempts";
-NSString *const EDQueueStorageJobStampKey = @"stamp";
+static NSString *const EDQueueNameKey = @"name";
+static NSString *const EDQueueDataKey = @"data";
 
 
 NS_ASSUME_NONNULL_BEGIN
 
 @interface EDQueue ()
-{
-    BOOL _isRunning;
-    BOOL _isActive;
-    NSUInteger _retryLimit;
-}
 
-@property (nonatomic) EDQueueStorageEngine *engine;
 @property (nonatomic, readwrite, nullable) NSString *activeTask;
 
 @end
 
-//
 
 @implementation EDQueue
 
-@synthesize isRunning = _isRunning;
-@synthesize isActive = _isActive;
-@synthesize retryLimit = _retryLimit;
-
-#pragma mark - Singleton
-
-+ (EDQueue *)sharedInstance
-{
-    static EDQueue *singleton = nil;
-    static dispatch_once_t once = 0;
-    dispatch_once(&once, ^{
-        singleton = [[self alloc] init];
-    });
-    return singleton;
-}
-
-#pragma mark - Init
-
-- (id)init
+- (instancetype)initWithPersistentStore:(id<EDQueuePersistentStorage>)persistentStore
 {
     self = [super init];
     if (self) {
-        _engine     = [[EDQueueStorageEngine alloc] init];
         _retryLimit = 4;
+        _storage = persistentStore;
     }
     return self;
 }
 
-- (void)dealloc
-{    
-    self.delegate = nil;
-    _engine = nil;
-}
 
 #pragma mark - Public methods
 
@@ -90,7 +53,7 @@ - (void)dealloc
  */
 - (void)enqueueJob:(EDQueueJob *)job
 {
-    [self.engine createJob:job];
+    [self.storage createJob:job];
     [self tick];
 }
 
@@ -103,7 +66,7 @@ - (void)enqueueJob:(EDQueueJob *)job
  */
 - (BOOL)jobExistsForTask:(NSString *)task
 {
-    BOOL jobExists = [self.engine jobExistsForTask:task];
+    BOOL jobExists = [self.storage jobExistsForTask:task];
     return jobExists;
 }
 
@@ -129,7 +92,7 @@ - (BOOL)jobIsActiveForTask:(NSString *)task
  */
 - (nullable EDQueueJob *)nextJobForTask:(NSString *)task
 {
-    EDQueueJob *nextJobForTask = [self.engine fetchJobForTask:task];
+    EDQueueJob *nextJobForTask = [self.storage fetchNextJobForTask:task];
     return nextJobForTask;
 }
 
@@ -146,7 +109,6 @@ - (void)start
 
         NSDictionary *object = @{ EDQueueNameKey : EDQueueDidStart };
 
-//        [self performSelectorOnMainThread:@selector(postNotificationOnMainThread:) withObject:object waitUntilDone:NO];
         [self postNotificationOnMainThread:object];
     }
 }
@@ -163,8 +125,6 @@ - (void)stop
         _isRunning = NO;
 
         NSDictionary *object = @{ EDQueueNameKey : EDQueueDidStop };
-
-//        [self performSelectorOnMainThread:@selector(postNotification:) withObject:object waitUntilDone:NO];
         [self postNotificationOnMainThread:object];
     }
 }
@@ -179,7 +139,7 @@ - (void)stop
  */
 - (void)empty
 {
-    [self.engine removeAllJobs];
+    [self.storage removeAllJobs];
 }
 
 
@@ -194,10 +154,10 @@ - (void)tick
 {
     dispatch_queue_t gcd = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0);
     dispatch_async(gcd, ^{
-        if (self.isRunning && !self.isActive && [self.engine fetchJobCount] > 0) {
+        if (self.isRunning && !self.isActive && [self.storage jobCount] > 0) {
             // Start job
             _isActive = YES;
-            EDQueueJob *job = [self.engine fetchJob];
+            EDQueueJob *job = [self.storage fetchNextJob];
             self.activeTask = job.task;
 
             // Pass job to delegate
@@ -220,7 +180,7 @@ - (void)processJob:(EDQueueJob*)job withResult:(EDQueueResult)result
                                                  EDQueueDataKey : job
                                                  }];
 
-            [self.engine removeJob:job];
+            [self.storage removeJob:job];
             break;
 
         case EDQueueResultFail:
@@ -233,9 +193,9 @@ - (void)processJob:(EDQueueJob*)job withResult:(EDQueueResult)result
             NSUInteger currentAttempt = job.attempts.integerValue + 1;
 
             if (currentAttempt < self.retryLimit) {
-                [self.engine incrementAttemptForJob:job];
+                [self.storage incrementAttemptForJob:job];
             } else {
-                [self.engine removeJob:job];
+                [self.storage removeJob:job];
             }
             break;
         case EDQueueResultCritical:
@@ -246,15 +206,15 @@ - (void)processJob:(EDQueueJob*)job withResult:(EDQueueResult)result
                                                  }];
 
             [self errorWithMessage:@"Critical error. Job canceled."];
-            [self.engine removeJob:job];
+            [self.storage removeJob:job];
             break;
     }
 
     // Clean-up
     _isActive = NO;
 
     // Drain
-    if ([self.engine fetchJobCount] == 0) {
+    if ([self.storage jobCount] == 0) {
 
         [self postNotificationOnMainThread:@{
                                              EDQueueNameKey : EDQueueDidDrain,

EDQueue/EDQueuePersistentStorageProtocol.h

@@ -0,0 +1,30 @@
+//
+//  EDQueuePersistentStorageProtocol.h
+//  queue
+//
+//  Created by Oleg Shanyuk on 19/02/16.
+//  Copyright © 2016 DIY, Co. All rights reserved.
+//
+
+@import Foundation;
+
+NS_ASSUME_NONNULL_BEGIN
+
+@class EDQueueJob;
+
+@protocol EDQueuePersistentStorage <NSObject>
+
+- (void)createJob:(EDQueueJob *)job;
+- (BOOL)jobExistsForTask:(NSString *)task;
+- (void)incrementAttemptForJob:(EDQueueJob *)jid;
+
+- (void)removeJob:(EDQueueJob *)jid;
+- (void)removeAllJobs;
+
+- (NSUInteger)jobCount;
+- (nullable EDQueueJob *)fetchNextJob;
+- (nullable EDQueueJob *)fetchNextJobForTask:(NSString *)task;
+
+@end
+
+NS_ASSUME_NONNULL_END

EDQueue/EDQueueStorageEngine.h

@@ -8,20 +8,18 @@
 
 @import Foundation;
 
+#import "EDQueuePersistentStorageProtocol.h"
+
 NS_ASSUME_NONNULL_BEGIN
 
 @class EDQueueJob;
 
-@interface EDQueueStorageEngine : NSObject
+@interface EDQueueStorageEngine : NSObject<EDQueuePersistentStorage>
+
+- (nullable instancetype)initWithName:(NSString *)name;
+- (instancetype)init NS_UNAVAILABLE;
 
-- (void)createJob:(EDQueueJob *)job;
-- (BOOL)jobExistsForTask:(NSString *)task;
-- (void)incrementAttemptForJob:(EDQueueJob *)jid;
-- (void)removeJob:(EDQueueJob *)jid;
-- (void)removeAllJobs;
-- (NSUInteger)fetchJobCount;
-- (nullable EDQueueJob *)fetchJob;
-- (nullable EDQueueJob *)fetchJobForTask:(NSString *)task;
++ (void)deleteDatabaseName:(NSString *)name;
 
 @end