315 lines
16 KiB
Objective-C
315 lines
16 KiB
Objective-C
/*
|
|
* Copyright 2017 Google
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#import <Foundation/Foundation.h>
|
|
#import "FIRDataEventType.h"
|
|
#import "FIRDataSnapshot.h"
|
|
|
|
NS_ASSUME_NONNULL_BEGIN
|
|
|
|
/**
|
|
* A FIRDatabaseHandle is used to identify listeners of Firebase Database events. These handles
|
|
* are returned by observeEventType: and and can later be passed to removeObserverWithHandle: to
|
|
* stop receiving updates.
|
|
*/
|
|
typedef NSUInteger FIRDatabaseHandle NS_SWIFT_NAME(DatabaseHandle);
|
|
|
|
/**
|
|
* A FIRDatabaseQuery instance represents a query over the data at a particular location.
|
|
*
|
|
* You create one by calling one of the query methods (queryOrderedByChild:, queryStartingAtValue:, etc.)
|
|
* on a FIRDatabaseReference. The query methods can be chained to further specify the data you are interested in
|
|
* observing
|
|
*/
|
|
NS_SWIFT_NAME(DatabaseQuery)
|
|
@interface FIRDatabaseQuery : NSObject
|
|
|
|
|
|
#pragma mark - Attach observers to read data
|
|
|
|
/**
|
|
* observeEventType:withBlock: is used to listen for data changes at a particular location.
|
|
* This is the primary way to read data from the Firebase Database. Your block will be triggered
|
|
* for the initial data and again whenever the data changes.
|
|
*
|
|
* Use removeObserverWithHandle: to stop receiving updates.
|
|
*
|
|
* @param eventType The type of event to listen for.
|
|
* @param block The block that should be called with initial data and updates. It is passed the data as a FIRDataSnapshot.
|
|
* @return A handle used to unregister this block later using removeObserverWithHandle:
|
|
*/
|
|
- (FIRDatabaseHandle)observeEventType:(FIRDataEventType)eventType withBlock:(void (^)(FIRDataSnapshot *snapshot))block;
|
|
|
|
|
|
/**
|
|
* observeEventType:andPreviousSiblingKeyWithBlock: is used to listen for data changes at a particular location.
|
|
* This is the primary way to read data from the Firebase Database. Your block will be triggered
|
|
* for the initial data and again whenever the data changes. In addition, for FIRDataEventTypeChildAdded, FIRDataEventTypeChildMoved, and
|
|
* FIRDataEventTypeChildChanged events, your block will be passed the key of the previous node by priority order.
|
|
*
|
|
* Use removeObserverWithHandle: to stop receiving updates.
|
|
*
|
|
* @param eventType The type of event to listen for.
|
|
* @param block The block that should be called with initial data and updates. It is passed the data as a FIRDataSnapshot
|
|
* and the previous child's key.
|
|
* @return A handle used to unregister this block later using removeObserverWithHandle:
|
|
*/
|
|
- (FIRDatabaseHandle)observeEventType:(FIRDataEventType)eventType andPreviousSiblingKeyWithBlock:(void (^)(FIRDataSnapshot *snapshot, NSString *__nullable prevKey))block;
|
|
|
|
|
|
/**
|
|
* observeEventType:withBlock: is used to listen for data changes at a particular location.
|
|
* This is the primary way to read data from the Firebase Database. Your block will be triggered
|
|
* for the initial data and again whenever the data changes.
|
|
*
|
|
* The cancelBlock will be called if you will no longer receive new events due to no longer having permission.
|
|
*
|
|
* Use removeObserverWithHandle: to stop receiving updates.
|
|
*
|
|
* @param eventType The type of event to listen for.
|
|
* @param block The block that should be called with initial data and updates. It is passed the data as a FIRDataSnapshot.
|
|
* @param cancelBlock The block that should be called if this client no longer has permission to receive these events
|
|
* @return A handle used to unregister this block later using removeObserverWithHandle:
|
|
*/
|
|
- (FIRDatabaseHandle)observeEventType:(FIRDataEventType)eventType withBlock:(void (^)(FIRDataSnapshot *snapshot))block withCancelBlock:(nullable void (^)(NSError* error))cancelBlock;
|
|
|
|
|
|
/**
|
|
* observeEventType:andPreviousSiblingKeyWithBlock: is used to listen for data changes at a particular location.
|
|
* This is the primary way to read data from the Firebase Database. Your block will be triggered
|
|
* for the initial data and again whenever the data changes. In addition, for FIRDataEventTypeChildAdded, FIRDataEventTypeChildMoved, and
|
|
* FIRDataEventTypeChildChanged events, your block will be passed the key of the previous node by priority order.
|
|
*
|
|
* The cancelBlock will be called if you will no longer receive new events due to no longer having permission.
|
|
*
|
|
* Use removeObserverWithHandle: to stop receiving updates.
|
|
*
|
|
* @param eventType The type of event to listen for.
|
|
* @param block The block that should be called with initial data and updates. It is passed the data as a FIRDataSnapshot
|
|
* and the previous child's key.
|
|
* @param cancelBlock The block that should be called if this client no longer has permission to receive these events
|
|
* @return A handle used to unregister this block later using removeObserverWithHandle:
|
|
*/
|
|
- (FIRDatabaseHandle)observeEventType:(FIRDataEventType)eventType andPreviousSiblingKeyWithBlock:(void (^)(FIRDataSnapshot *snapshot, NSString *__nullable prevKey))block withCancelBlock:(nullable void (^)(NSError* error))cancelBlock;
|
|
|
|
|
|
/**
|
|
* This is equivalent to observeEventType:withBlock:, except the block is immediately canceled after the initial data is returned.
|
|
*
|
|
* @param eventType The type of event to listen for.
|
|
* @param block The block that should be called. It is passed the data as a FIRDataSnapshot.
|
|
*/
|
|
- (void)observeSingleEventOfType:(FIRDataEventType)eventType withBlock:(void (^)(FIRDataSnapshot *snapshot))block;
|
|
|
|
|
|
/**
|
|
* This is equivalent to observeEventType:withBlock:, except the block is immediately canceled after the initial data is returned. In addition, for FIRDataEventTypeChildAdded, FIRDataEventTypeChildMoved, and
|
|
* FIRDataEventTypeChildChanged events, your block will be passed the key of the previous node by priority order.
|
|
*
|
|
* @param eventType The type of event to listen for.
|
|
* @param block The block that should be called. It is passed the data as a FIRDataSnapshot and the previous child's key.
|
|
*/
|
|
- (void)observeSingleEventOfType:(FIRDataEventType)eventType andPreviousSiblingKeyWithBlock:(void (^)(FIRDataSnapshot *snapshot, NSString *__nullable prevKey))block;
|
|
|
|
|
|
/**
|
|
* This is equivalent to observeEventType:withBlock:, except the block is immediately canceled after the initial data is returned.
|
|
*
|
|
* The cancelBlock will be called if you do not have permission to read data at this location.
|
|
*
|
|
* @param eventType The type of event to listen for.
|
|
* @param block The block that should be called. It is passed the data as a FIRDataSnapshot.
|
|
* @param cancelBlock The block that will be called if you don't have permission to access this data
|
|
*/
|
|
- (void)observeSingleEventOfType:(FIRDataEventType)eventType withBlock:(void (^)(FIRDataSnapshot *snapshot))block withCancelBlock:(nullable void (^)(NSError* error))cancelBlock;
|
|
|
|
|
|
/**
|
|
* This is equivalent to observeEventType:withBlock:, except the block is immediately canceled after the initial data is returned. In addition, for FIRDataEventTypeChildAdded, FIRDataEventTypeChildMoved, and
|
|
* FIRDataEventTypeChildChanged events, your block will be passed the key of the previous node by priority order.
|
|
*
|
|
* The cancelBlock will be called if you do not have permission to read data at this location.
|
|
*
|
|
* @param eventType The type of event to listen for.
|
|
* @param block The block that should be called. It is passed the data as a FIRDataSnapshot and the previous child's key.
|
|
* @param cancelBlock The block that will be called if you don't have permission to access this data
|
|
*/
|
|
- (void)observeSingleEventOfType:(FIRDataEventType)eventType andPreviousSiblingKeyWithBlock:(void (^)(FIRDataSnapshot *snapshot, NSString *__nullable prevKey))block withCancelBlock:(nullable void (^)(NSError* error))cancelBlock;
|
|
|
|
|
|
#pragma mark - Detaching observers
|
|
|
|
/**
|
|
* Detach a block previously attached with observeEventType:withBlock:.
|
|
*
|
|
* @param handle The handle returned by the call to observeEventType:withBlock: which we are trying to remove.
|
|
*/
|
|
- (void) removeObserverWithHandle:(FIRDatabaseHandle)handle;
|
|
|
|
|
|
/**
|
|
* Detach all blocks previously attached to this Firebase Database location with observeEventType:withBlock:
|
|
*/
|
|
- (void) removeAllObservers;
|
|
|
|
/**
|
|
* By calling `keepSynced:YES` on a location, the data for that location will automatically be downloaded and
|
|
* kept in sync, even when no listeners are attached for that location. Additionally, while a location is kept
|
|
* synced, it will not be evicted from the persistent disk cache.
|
|
*
|
|
* @param keepSynced Pass YES to keep this location synchronized, pass NO to stop synchronization.
|
|
*/
|
|
- (void) keepSynced:(BOOL)keepSynced;
|
|
|
|
|
|
#pragma mark - Querying and limiting
|
|
|
|
/**
|
|
* queryLimitedToFirst: is used to generate a reference to a limited view of the data at this location.
|
|
* The FIRDatabaseQuery instance returned by queryLimitedToFirst: will respond to at most the first limit child nodes.
|
|
*
|
|
* @param limit The upper bound, inclusive, for the number of child nodes to receive events for
|
|
* @return A FIRDatabaseQuery instance, limited to at most limit child nodes.
|
|
*/
|
|
- (FIRDatabaseQuery *)queryLimitedToFirst:(NSUInteger)limit;
|
|
|
|
|
|
/**
|
|
* queryLimitedToLast: is used to generate a reference to a limited view of the data at this location.
|
|
* The FIRDatabaseQuery instance returned by queryLimitedToLast: will respond to at most the last limit child nodes.
|
|
*
|
|
* @param limit The upper bound, inclusive, for the number of child nodes to receive events for
|
|
* @return A FIRDatabaseQuery instance, limited to at most limit child nodes.
|
|
*/
|
|
- (FIRDatabaseQuery *)queryLimitedToLast:(NSUInteger)limit;
|
|
|
|
/**
|
|
* queryOrderBy: is used to generate a reference to a view of the data that's been sorted by the values of
|
|
* a particular child key. This method is intended to be used in combination with queryStartingAtValue:,
|
|
* queryEndingAtValue:, or queryEqualToValue:.
|
|
*
|
|
* @param key The child key to use in ordering data visible to the returned FIRDatabaseQuery
|
|
* @return A FIRDatabaseQuery instance, ordered by the values of the specified child key.
|
|
*/
|
|
- (FIRDatabaseQuery *)queryOrderedByChild:(NSString *)key;
|
|
|
|
/**
|
|
* queryOrderedByKey: is used to generate a reference to a view of the data that's been sorted by child key.
|
|
* This method is intended to be used in combination with queryStartingAtValue:, queryEndingAtValue:,
|
|
* or queryEqualToValue:.
|
|
*
|
|
* @return A FIRDatabaseQuery instance, ordered by child keys.
|
|
*/
|
|
- (FIRDatabaseQuery *) queryOrderedByKey;
|
|
|
|
/**
|
|
* queryOrderedByValue: is used to generate a reference to a view of the data that's been sorted by child value.
|
|
* This method is intended to be used in combination with queryStartingAtValue:, queryEndingAtValue:,
|
|
* or queryEqualToValue:.
|
|
*
|
|
* @return A FIRDatabaseQuery instance, ordered by child value.
|
|
*/
|
|
- (FIRDatabaseQuery *) queryOrderedByValue;
|
|
|
|
/**
|
|
* queryOrderedByPriority: is used to generate a reference to a view of the data that's been sorted by child
|
|
* priority. This method is intended to be used in combination with queryStartingAtValue:, queryEndingAtValue:,
|
|
* or queryEqualToValue:.
|
|
*
|
|
* @return A FIRDatabaseQuery instance, ordered by child priorities.
|
|
*/
|
|
- (FIRDatabaseQuery *) queryOrderedByPriority;
|
|
|
|
/**
|
|
* queryStartingAtValue: is used to generate a reference to a limited view of the data at this location.
|
|
* The FIRDatabaseQuery instance returned by queryStartingAtValue: will respond to events at nodes with a value
|
|
* greater than or equal to startValue.
|
|
*
|
|
* @param startValue The lower bound, inclusive, for the value of data visible to the returned FIRDatabaseQuery
|
|
* @return A FIRDatabaseQuery instance, limited to data with value greater than or equal to startValue
|
|
*/
|
|
- (FIRDatabaseQuery *)queryStartingAtValue:(nullable id)startValue;
|
|
|
|
/**
|
|
* queryStartingAtValue:childKey: is used to generate a reference to a limited view of the data at this location.
|
|
* The FIRDatabaseQuery instance returned by queryStartingAtValue:childKey will respond to events at nodes with a value
|
|
* greater than startValue, or equal to startValue and with a key greater than or equal to childKey. This is most
|
|
* useful when implementing pagination in a case where multiple nodes can match the startValue.
|
|
*
|
|
* @param startValue The lower bound, inclusive, for the value of data visible to the returned FIRDatabaseQuery
|
|
* @param childKey The lower bound, inclusive, for the key of nodes with value equal to startValue
|
|
* @return A FIRDatabaseQuery instance, limited to data with value greater than or equal to startValue
|
|
*/
|
|
- (FIRDatabaseQuery *)queryStartingAtValue:(nullable id)startValue childKey:(nullable NSString *)childKey;
|
|
|
|
/**
|
|
* queryEndingAtValue: is used to generate a reference to a limited view of the data at this location.
|
|
* The FIRDatabaseQuery instance returned by queryEndingAtValue: will respond to events at nodes with a value
|
|
* less than or equal to endValue.
|
|
*
|
|
* @param endValue The upper bound, inclusive, for the value of data visible to the returned FIRDatabaseQuery
|
|
* @return A FIRDatabaseQuery instance, limited to data with value less than or equal to endValue
|
|
*/
|
|
- (FIRDatabaseQuery *)queryEndingAtValue:(nullable id)endValue;
|
|
|
|
/**
|
|
* queryEndingAtValue:childKey: is used to generate a reference to a limited view of the data at this location.
|
|
* The FIRDatabaseQuery instance returned by queryEndingAtValue:childKey will respond to events at nodes with a value
|
|
* less than endValue, or equal to endValue and with a key less than or equal to childKey. This is most useful when
|
|
* implementing pagination in a case where multiple nodes can match the endValue.
|
|
*
|
|
* @param endValue The upper bound, inclusive, for the value of data visible to the returned FIRDatabaseQuery
|
|
* @param childKey The upper bound, inclusive, for the key of nodes with value equal to endValue
|
|
* @return A FIRDatabaseQuery instance, limited to data with value less than or equal to endValue
|
|
*/
|
|
- (FIRDatabaseQuery *)queryEndingAtValue:(nullable id)endValue childKey:(nullable NSString *)childKey;
|
|
|
|
/**
|
|
* queryEqualToValue: is used to generate a reference to a limited view of the data at this location.
|
|
* The FIRDatabaseQuery instance returned by queryEqualToValue: will respond to events at nodes with a value equal
|
|
* to the supplied argument.
|
|
*
|
|
* @param value The value that the data returned by this FIRDatabaseQuery will have
|
|
* @return A FIRDatabaseQuery instance, limited to data with the supplied value.
|
|
*/
|
|
- (FIRDatabaseQuery *)queryEqualToValue:(nullable id)value;
|
|
|
|
/**
|
|
* queryEqualToValue:childKey: is used to generate a reference to a limited view of the data at this location.
|
|
* The FIRDatabaseQuery instance returned by queryEqualToValue:childKey will respond to events at nodes with a value
|
|
* equal to the supplied argument and with their key equal to childKey. There will be at most one node that matches
|
|
* because child keys are unique.
|
|
*
|
|
* @param value The value that the data returned by this FIRDatabaseQuery will have
|
|
* @param childKey The name of nodes with the right value
|
|
* @return A FIRDatabaseQuery instance, limited to data with the supplied value and the key.
|
|
*/
|
|
- (FIRDatabaseQuery *)queryEqualToValue:(nullable id)value childKey:(nullable NSString *)childKey;
|
|
|
|
|
|
#pragma mark - Properties
|
|
|
|
/**
|
|
* Gets a FIRDatabaseReference for the location of this query.
|
|
*
|
|
* @return A FIRDatabaseReference for the location of this query.
|
|
*/
|
|
@property (nonatomic, readonly, strong) FIRDatabaseReference * ref;
|
|
|
|
@end
|
|
|
|
NS_ASSUME_NONNULL_END
|