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FirebaseFirestore Framework Reference

FIRDocumentReference


@interface FIRDocumentReference : NSObject

A DocumentReference refers to a document location in a Firestore database and can be used to write, read, or listen to the location. The document at the referenced location may or may not exist. A DocumentReference can also be used to create a CollectionReference to a subcollection.

  • The ID of the document referred to.

    Declaration

    Objective-C

    @property (nonatomic, strong, readonly) NSString *_Nonnull documentID;

  • A reference to the collection to which this DocumentReference belongs.

    Declaration

    Objective-C

    @property (nonatomic, strong, readonly) FIRCollectionReference *_Nonnull parent;

  • The Firestore for the Firestore database (useful for performing transactions, etc.).

    Declaration

    Objective-C

    @property (nonatomic, strong, readonly) FIRFirestore *_Nonnull firestore;

  • A string representing the path of the referenced document (relative to the root of the database).

    Declaration

    Objective-C

    @property (nonatomic, strong, readonly) NSString *_Nonnull path;

  • Gets a CollectionReference referring to the collection at the specified path, relative to this document.

    Declaration

    Objective-C

    - (nonnull FIRCollectionReference *)collectionWithPath:
    (nonnull NSString *)collectionPath;

    Parameters

    collectionPath

    The slash-separated relative path of the collection for which to get a CollectionReference.

    Return Value

    The CollectionReference at the specified collectionPath.

Writing Data

  • Writes to the document referred to by DocumentReference. If the document doesn’t yet exist, this method creates it and then sets the data. If the document exists, this method overwrites the document data with the new values.

    Declaration

    Objective-C

    - (void)setData:(nonnull NSDictionary<NSString *, id> *)documentData;

    Parameters

    documentData

    A Dictionary that contains the fields and data to write to the document.

  • Writes to the document referred to by this DocumentReference. If the document does not yet exist, it will be created. If you pass merge:true, the provided data will be merged into any existing document.

    Declaration

    Objective-C

    - (void)setData:(nonnull NSDictionary<NSString *, id> *)documentData
          merge:(BOOL)merge;

    Parameters

    documentData

    A Dictionary that contains the fields and data to write to the document.
    merge

    Whether to merge the provided data into any existing document. If enabled, all omitted fields remain untouched. If your input sets any field to an empty dictionary, any nested field is overwritten.

  • Writes to the document referred to by document and only replace the fields specified under mergeFields. Any field that is not specified in mergeFields is ignored and remains untouched. If the document doesn’t yet exist, this method creates it and then sets the data.

    It is an error to include a field in mergeFields that does not have a corresponding value in the data dictionary.

    Declaration

    Objective-C

    - (void)setData:(nonnull NSDictionary<NSString *, id> *)documentData
    mergeFields:(nonnull NSArray<id> *)mergeFields;

    Parameters

    documentData

    A Dictionary containing the fields that make up the document to be written.
    mergeFields

    An Array that contains a list of String or FieldPath elements specifying which fields to merge. Fields can contain dots to reference nested fields within the document. If your input sets any field to an empty dictionary, any nested field is overwritten.

  • Overwrites the document referred to by this DocumentReference. If no document exists, it is created. If a document already exists, it is overwritten.

    Declaration

    Objective-C

    - (void)setData:(nonnull NSDictionary<NSString *, id> *)documentData
     completion:(nullable void (^)(NSError *_Nullable))completion;

    Parameters

    documentData

    A Dictionary containing the fields that make up the document to be written.
    completion

    A block to execute once the document has been successfully written to the server. This block will not be called while the client is offline, though local changes will be visible immediately.

  • Writes to the document referred to by this DocumentReference. If the document does not yet exist, it will be created. If you pass merge:true, the provided data will be merged into any existing document.

    Declaration

    Objective-C

    - (void)setData:(nonnull NSDictionary<NSString *, id> *)documentData
          merge:(BOOL)merge
     completion:(nullable void (^)(NSError *_Nullable))completion;

    Parameters

    documentData

    A Dictionary containing the fields that make up the document to be written.
    merge

    Whether to merge the provided data into any existing document. If your input sets any field to an empty dictionary, any nested field is overwritten.
    completion

    A block to execute once the document has been successfully written to the server. This block will not be called while the client is offline, though local changes will be visible immediately.

  • Writes to the document referred to by document and only replace the fields specified under mergeFields. Any field that is not specified in mergeFields is ignored and remains untouched. If the document doesn’t yet exist, this method creates it and then sets the data.

    It is an error to include a field in mergeFields that does not have a corresponding value in the data dictionary.

    Declaration

    Objective-C

    - (void)setData:(nonnull NSDictionary<NSString *, id> *)documentData
    mergeFields:(nonnull NSArray<id> *)mergeFields
     completion:(nullable void (^)(NSError *_Nullable))completion;

    Parameters

    documentData

    A Dictionary containing the fields that make up the document to be written.
    mergeFields

    An Array that contains a list of String or FieldPath elements specifying which fields to merge. Fields can contain dots to reference nested fields within the document. If your input sets any field to an empty dictionary, any nested field is overwritten.
    completion

    A block to execute once the document has been successfully written to the server. This block will not be called while the client is offline, though local changes will be visible immediately.

  • Updates fields in the document referred to by this DocumentReference. If the document does not exist, the update fails (specify a completion block to be notified).

    Declaration

    Objective-C

    - (void)updateData:(nonnull NSDictionary<id, id> *)fields;

    Parameters

    fields

    A Dictionary containing the fields (expressed as an String or FieldPath) and values with which to update the document.

  • Updates fields in the document referred to by this DocumentReference. If the document does not exist, the update fails and the specified completion block receives an error.

    Declaration

    Objective-C

    - (void)updateData:(nonnull NSDictionary<id, id> *)fields
        completion:(nullable void (^)(NSError *_Nullable))completion;

    Parameters

    fields

    A Dictionary containing the fields (expressed as a String or FieldPath) and values with which to update the document.
    completion

    A block to execute when the update is complete. If the update is successful the error parameter will be nil, otherwise it will give an indication of how the update failed. This block will only execute when the client is online and the commit has completed against the server. The completion handler will not be called when the device is offline, though local changes will be visible immediately.

  • Deletes the document referred to by this DocumentReference.

    Declaration

    Objective-C

    - (void)deleteDocument;

  • Deletes the document referred to by this DocumentReference.

    Declaration

    Objective-C

    - (void)deleteDocumentWithCompletion:
    (nullable void (^)(NSError *_Nullable))completion;

    Parameters

    completion

    A block to execute once the document has been successfully written to the server. This block will not be called while the client is offline, though local changes will be visible immediately.

Retrieving Data

  • Reads the document referenced by this DocumentReference.

    This method attempts to provide up-to-date data when possible by waiting for data from the server, but it may return cached data or fail if you are offline and the server cannot be reached. See the getDocument(source:completion:) method to change this behavior.

    Declaration

    Objective-C

    - (void)getDocumentWithCompletion:
    (nonnull void (^)(FIRDocumentSnapshot *_Nullable,
                      NSError *_Nullable))completion;

    Parameters

    completion

    a block to execute once the document has been successfully read.

  • Reads the document referenced by this DocumentReference.

    Declaration

    Objective-C

    - (void)getDocumentWithSource:(FIRFirestoreSource)source
                   completion:(nonnull void (^)(FIRDocumentSnapshot *_Nullable,
                                                NSError *_Nullable))completion;

    Parameters

    source

    indicates whether the results should be fetched from the cache only (Source.cache), the server only (Source.server), or to attempt the server and fall back to the cache (Source.default).
    completion

    a block to execute once the document has been successfully read.

  • Attaches a listener for DocumentSnapshot events.

    Declaration

    Objective-C

    - (nonnull id<FIRListenerRegistration>)addSnapshotListener:
    (nonnull void (^)(FIRDocumentSnapshot *_Nullable,
                      NSError *_Nullable))listener;

    Parameters

    listener

    The listener to attach.

    Return Value

    A ListenerRegistration that can be used to remove this listener.

  • Attaches a listener for DocumentSnapshot events.

    Declaration

    Objective-C

    - (nonnull id<FIRListenerRegistration>)
    addSnapshotListenerWithIncludeMetadataChanges:(BOOL)includeMetadataChanges
                                         listener:
                                             (nonnull void (^)(
                                                 FIRDocumentSnapshot *_Nullable,
                                                 NSError *_Nullable))listener;

    Parameters

    includeMetadataChanges

    Whether metadata-only changes (i.e. only DocumentSnapshot.metadata changed) should trigger snapshot events.
    listener

    The listener to attach.

    Return Value

    A ListenerRegistration that can be used to remove this listener.

  • Attaches a listener for DocumentSnapshot events.

    Declaration

    Objective-C

    - (nonnull id<FIRListenerRegistration>)
    addSnapshotListenerWithOptions:(nonnull FIRSnapshotListenOptions *)options
                          listener:
                              (nonnull void (^)(FIRDocumentSnapshot *_Nullable,
                                                NSError *_Nullable))listener;

    Parameters

    options

    Sets snapshot listener options, including whether metadata-only changes should trigger snapshot events, the source to listen to, the executor to use to call the listener, or the activity to scope the listener to.
    listener

    The listener to attach.

    Return Value

    A ListenerRegistration that can be used to remove this listener.