Signal-iOS/YapDatabase/Key-Value/YapDatabaseTransaction+Timestamp.m
2013-03-14 17:27:10 -07:00

363 lines
11 KiB
Objective-C

#import "YapDatabaseTransaction+Timestamp.h"
#import "YapDatabaseLogging.h"
#if ! __has_feature(objc_arc)
#warning This file must be compiled with ARC. Use -fobjc-arc flag (or convert project to ARC).
#endif
@implementation YapDatabaseReadTransaction (Timestamp)
/**
* This method invokes metadataForKey: and checks the result.
* If the resulting metadata is of class NSDate, it is returned.
* Otherwise it returns nil.
**/
- (NSDate *)timestampForKey:(NSString *)key
{
id metadata = [self metadataForKey:key];
if ([metadata isKindOfClass:[NSDate class]])
return (NSDate *)metadata;
else
return nil;
}
/**
* Returns the list of keys, ordered by metadata timestamp.
*
* What do I pass for the 'ordered' parameter? Use:
* - To enumerate from oldest to newest timestamp (1990,2004,2012): NSOrderedAscending
* - To enumerate from newest to oldest timestamp (2012,2004,1990): NSOrderedDescending
*
* Keys without an associated metadata timestamp are not included in the list.
*
* If you don't pass a proper value for the ordered parameter (either NSOrderedAscending or NSOrderedDescending),
* then the default value of NSOrderedAscending is used.
**/
- (NSArray *)allKeysOrdered:(NSComparisonResult)NSOrderedAscendingOrDescending
{
// Extract the key/timestamp pairs (those that have a metadata timestamp).
NSMutableDictionary *subMetadataDict = [NSMutableArray array];
Class NSDateClass = [NSDate class];
[self enumerateKeysAndMetadataUsingBlock:^(NSString *key, id metadata, BOOL *stop){
if ([metadata isKindOfClass:NSDateClass])
{
[subMetadataDict setObject:metadata forKey:key];
}
}];
// Check desired sorting order.
// Default (if passed inappropriate value) is NSOrderedAscending.
BOOL enumerateAscending = (NSOrderedAscendingOrDescending != NSOrderedDescending);
// Sort keys according to desired sort order.
return [subMetadataDict keysSortedByValueUsingComparator:^NSComparisonResult(id obj1, id obj2) {
__unsafe_unretained NSDate *date1 = (NSDate *)obj1;
__unsafe_unretained NSDate *date2 = (NSDate *)obj2;
NSComparisonResult result = [date1 compare:date2];
if (enumerateAscending)
{
// normal sort ordering
return result;
}
else
{
// reverse sort ordering
if (result == NSOrderedAscending) return NSOrderedDescending;
if (result == NSOrderedDescending) return NSOrderedAscending;
else return result;
}
}];
}
/**
* Allows you to enumerate the keys based on their metadata timestamp.
*
* What do I pass for the 'ordered' parameter? Use:
* - To enumerate from oldest to newest timestamp (1990,2004,2012): NSOrderedAscending
* - To enumerate from newest to oldest timestamp (2012,2004,1990): NSOrderedDescending
*
* Keys without a metadata timestamp are not included in the enumeration.
*
* If you don't pass a proper value for the ordered parameter (either NSOrderedAscending or NSOrderedDescending),
* then the default value of NSOrderedAscending is used.
**/
- (void)enumerateKeysAndMetadataOrdered:(NSComparisonResult)NSOrderedAscendingOrDescending
usingBlock:
(void (^)(NSUInteger idx, NSString *key, NSDate *timestamp, BOOL *stop))block
{
if (!block) return;
// Extract the key/timestamp pairs (those that have a metadata timestamp).
NSMutableDictionary *subMetadataDict = [NSMutableArray array];
Class NSDateClass = [NSDate class];
[self enumerateKeysAndMetadataUsingBlock:^(NSString *key, id metadata, BOOL *stop){
if ([metadata isKindOfClass:NSDateClass])
{
[subMetadataDict setObject:metadata forKey:key];
}
}];
// Check desired sorting order.
// Default (if passed inappropriate value) is NSOrderedAscending.
BOOL enumerateAscending = (NSOrderedAscendingOrDescending != NSOrderedDescending);
// Sort keys according to desired sort order.
NSArray *orderedKeys = [subMetadataDict keysSortedByValueUsingComparator:^NSComparisonResult(id obj1, id obj2) {
__unsafe_unretained NSDate *date1 = (NSDate *)obj1;
__unsafe_unretained NSDate *date2 = (NSDate *)obj2;
NSComparisonResult result = [date1 compare:date2];
if (enumerateAscending)
{
// normal sort ordering
return result;
}
else
{
// reverse sort ordering
if (result == NSOrderedAscending) return NSOrderedDescending;
if (result == NSOrderedDescending) return NSOrderedAscending;
else return result;
}
}];
// Perform enumeration
[orderedKeys enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop){
__unsafe_unretained NSString *key = (NSString *)obj;
NSDate *timestamp = (NSDate *)[self metadataForKey:key];
block(idx, key, timestamp, stop);
}];
}
/**
* Allows you to enumerate the objects based on their metadata timestamp.
*
* What do I pass for the 'ordered' parameter? Use:
* - To enumerate from oldest to newest timestamp: NSOrderedAscending
* - To enumerate from newest to oldest timestamp: NSOrderedDescending
*
* Objects without a metadata timestamp are not included in the enumeration.
*
* If you don't pass a proper value for the ordered parameter (either NSOrderedAscending or NSOrderedDescending),
* then the default value of NSOrderedAscending is used.
**/
- (void)enumerateKeysAndObjectsOrdered:(NSComparisonResult)NSOrderedAscendingOrDescending usingBlock:
(void (^)(NSUInteger idx, NSString *key, id object, NSDate *timestamp, BOOL *stop))block
{
if (!block) return;
// Extract the key/timestamp pairs (those that have a metadata timestamp).
NSMutableDictionary *subMetadataDict = [NSMutableArray array];
Class NSDateClass = [NSDate class];
[self enumerateKeysAndMetadataUsingBlock:^(NSString *key, id metadata, BOOL *stop){
if ([metadata isKindOfClass:NSDateClass])
{
[subMetadataDict setObject:metadata forKey:key];
}
}];
// Check desired sorting order.
// Default (if passed inappropriate value) is NSOrderedAscending.
BOOL enumerateAscending = (NSOrderedAscendingOrDescending != NSOrderedDescending);
// Sort keys according to desired sort order.
NSArray *orderedKeys = [subMetadataDict keysSortedByValueUsingComparator:^NSComparisonResult(id obj1, id obj2) {
__unsafe_unretained NSDate *date1 = (NSDate *)obj1;
__unsafe_unretained NSDate *date2 = (NSDate *)obj2;
NSComparisonResult result = [date1 compare:date2];
if (enumerateAscending)
{
// normal sort ordering
return result;
}
else
{
// reverse sort ordering
if (result == NSOrderedAscending) return NSOrderedDescending;
if (result == NSOrderedDescending) return NSOrderedAscending;
else return result;
}
}];
// Perform enumeration
[orderedKeys enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop){
__unsafe_unretained NSString *key = (NSString *)obj;
id object = nil;
id metadata = nil;
[self getObject:&object metadata:&metadata forKey:key];
block(idx, key, object, (NSDate *)metadata, stop);
}];
}
@end
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#pragma mark -
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
@implementation YapDatabaseReadWriteTransaction (Timestamp)
/**
* This methods simply invokes setObject:forKey:withMetadata:, but provides stronger type safety for the compiler.
**/
- (void)setObject:(id)object forKey:(NSString *)key withTimestamp:(NSDate *)timestamp
{
[self setObject:object forKey:key withMetadata:timestamp];
}
/**
* This methods simply invokes setMetadata:forKey:, but provides stronger type safety for the compiler.
**/
- (void)setTimestamp:(NSDate *)timestamp forKey:(NSString *)key
{
[self setMetadata:timestamp forKey:key];
}
/**
* Removes any objects that have a metadata timestamp,
* and whose timestamp is earlier than the given date.
**/
- (NSArray *)removeObjectsEarlierThan:(NSDate *)inDate
{
if (inDate == nil) return nil;
NSMutableArray *keysToRemove = [NSMutableArray array];
Class NSDateClass = [NSDate class];
[self enumerateKeysAndMetadataUsingBlock:^(NSString *key, id metadata, BOOL *stop){
if ([metadata isKindOfClass:NSDateClass])
{
NSLog(@"Key(%@): Comparing date(%@) vs existing metadata(%@)", key, inDate, metadata);
if ([(NSDate *)metadata compare:inDate] == NSOrderedAscending)
{
NSLog(@"Found earlier date to remove (A): %@", key);
[keysToRemove addObject:key];
}
}
}];
[self removeObjectsForKeys:keysToRemove];
return keysToRemove;
}
/**
* Removes any objects that have a metadata timestamp,
* and whose timestamp is later than the given date.
**/
- (NSArray *)removeObjectsLaterThan:(NSDate *)inDate
{
if (inDate == nil) return nil;
NSMutableArray *keysToRemove = [NSMutableArray array];
Class NSDateClass = [NSDate class];
[self enumerateKeysAndMetadataUsingBlock:^(NSString *key, id metadata, BOOL *stop){
if ([metadata isKindOfClass:NSDateClass])
{
NSLog(@"Key(%@): Comparing date(%@) vs existing metadata(%@)", key, inDate, metadata);
if ([(NSDate *)metadata compare:inDate] == NSOrderedDescending)
{
NSLog(@"Found later date to remove (A): %@", key);
[keysToRemove addObject:key];
}
}
}];
[self removeObjectsForKeys:keysToRemove];
return keysToRemove;
}
/**
* Removes any objects that have a metadata timestamp,
* and whose timestamp is earlier or equal to the given data.
**/
- (NSArray *)removeObjectsEarlierThanOrEqualTo:(NSDate *)date
{
return [self removeObjectsFrom:nil to:date];
}
/**
* Removes any objects that have a metadata timestamp,
* and whose timestamp is later or equal to the given data.
**/
- (NSArray *)removeObjectsLaterThanOrEqualTo:(NSDate *)date
{
return [self removeObjectsFrom:date to:nil];
}
/**
* Removes any objects that lie within the given time range (inclusive).
*
* That is, if an object has a metadata timestamp, then the object is removed if:
* startDate >= timestamp <= endDate
*
* You may optionally pass nil for one of the dates.
* For example, if you passed nil for the endDate,
* then all objects with timestamp later than or equal to the given startDate would be removed.
**/
- (NSArray *)removeObjectsFrom:(NSDate *)startDate to:(NSDate *)endDate
{
if ((startDate == nil) && (endDate == nil)) return nil;
NSMutableArray *keysToRemove = [NSMutableArray array];
Class NSDateClass = [NSDate class];
[self enumerateKeysAndMetadataUsingBlock:^(NSString *key, id metadata, BOOL *stop){
if ([metadata isKindOfClass:NSDateClass])
{
NSDate *timestamp = (NSDate *)metadata;
BOOL remove = YES;
if (startDate && (timestamp != [timestamp laterDate:startDate]))
{
remove = NO;
}
if (endDate && (timestamp != [timestamp earlierDate:endDate]))
{
remove = NO;
}
if (remove)
[keysToRemove addObject:key];
}
}];
[self removeObjectsForKeys:keysToRemove];
return keysToRemove;
}
@end