import{initializeApp}from"firebase/app";import{getFirestore}from"firebase/firestore";//TODO:Replacethefollowingwithyourapp's Firebase project configuration//See:https://support.google.com/firebase/answer/7015592constfirebaseConfig={FIREBASE_CONFIGURATION};//InitializeFirebaseconstapp=initializeApp(firebaseConfig);//InitializeCloudFirestoreandgetareferencetotheserviceconstdb=getFirestore(app);

importfirebasefrom"firebase/app";import"firebase/firestore";//TODO:Replacethefollowingwithyourapp's Firebase project configuration//See:https://support.google.com/firebase/answer/7015592constfirebaseConfig={FIREBASE_CONFIGURATION};//InitializeFirebasefirebase.initializeApp(firebaseConfig);//InitializeCloudFirestoreandgetareferencetotheserviceconstdb=firebase.firestore();

importFirebaseCoreimportFirebaseFirestore

FirebaseApp.configure()letdb=Firestore.firestore()
AppDelegate.swift

@importFirebaseCore;@importFirebaseFirestore;//UseFirebaselibrarytoconfigureAPIs[FIRAppconfigure];

FIRFirestore*defaultFirestore=[FIRFirestorefirestore];
AppDelegate.m

// Access aCloud Firestore instance from your Activity

valdb=Firebase.firestore
DocSnippets.kt

// Access aCloud Firestore instance from your Activity

FirebaseFirestoredb=FirebaseFirestore.getInstance();
DocSnippets.java

db=FirebaseFirestore.instance;

// Make sure the call to `Create()` happens some time before you call Firestore::GetInstance().App::Create();Firestore*db=Firestore::GetInstance();
AppDelegate.mm

usingFirebase.Firestore;usingFirebase.Extensions;

FirebaseFirestoredb=FirebaseFirestore.DefaultInstance;

import{collection,addDoc}from"firebase/firestore";try{constdocRef=awaitaddDoc(collection(db,"users"),{first:"Ada",last:"Lovelace",born:1815});console.log("Document written with ID: ",docRef.id);}catch(e){console.error("Error adding document: ",e);}
add_ada_lovelace.js

db.collection("users").add({first:"Ada",last:"Lovelace",born:1815}).then((docRef)=>{console.log("Document written with ID: ",docRef.id);}).catch((error)=>{console.error("Error adding document: ",error);});
test.firestore.js

// Add a new document with a generated IDdo{letref=tryawaitdb.collection("users").addDocument(data:["first":"Ada","last":"Lovelace","born":1815])print("Document added with ID:\(ref.documentID)")}catch{print("Error adding document:\(error)")}
ViewController.swift

// Add a new document with a generated ID__blockFIRDocumentReference*ref=[[self.dbcollectionWithPath:@"users"]addDocumentWithData:@{@"first":@"Ada",@"last":@"Lovelace",@"born":@1815}completion:^(NSError*_Nullableerror){if(error!=nil){NSLog(@"Error adding document: %@",error);}else{NSLog(@"Document added with ID: %@",ref.documentID);}}];
ViewController.m

// Create a new user with a first and last namevaluser=hashMapOf("first"to"Ada","last"to"Lovelace","born"to1815,)// Add a new document with a generated IDdb.collection("users").add(user).addOnSuccessListener{documentReference->Log.d(TAG,"DocumentSnapshot added with ID:${documentReference.id}")}.addOnFailureListener{e->Log.w(TAG,"Error adding document",e)}
DocSnippets.kt

// Create a new user with a first and last nameMap<String,Object>user=newHashMap<>();user.put("first","Ada");user.put("last","Lovelace");user.put("born",1815);// Add a new document with a generated IDdb.collection("users").add(user).addOnSuccessListener(newOnSuccessListener<DocumentReference>(){@OverridepublicvoidonSuccess(DocumentReferencedocumentReference){Log.d(TAG,"DocumentSnapshot added with ID: "+documentReference.getId());}}).addOnFailureListener(newOnFailureListener(){@OverridepublicvoidonFailure(@NonNullExceptione){Log.w(TAG,"Error adding document",e);}});
DocSnippets.java

// Create a new user with a first and last namefinaluser=<String,dynamic>{"first":"Ada","last":"Lovelace","born":1815};// Add a new document with a generated IDdb.collection("users").add(user).then((DocumentReferencedoc)=>print('DocumentSnapshot added with ID:${doc.id}'));
firestore.dart

// Add a new document with a generated IDFuture<DocumentReference>user_ref=db->Collection("users").Add({{"first", FieldValue::String("Ada")},                                 {"last", FieldValue::String("Lovelace")},                                 {"born", FieldValue::Integer(1815)}});user_ref.OnCompletion([](constFuture<DocumentReference>&future){if(future.error()==Error::kErrorOk){std::cout <<"DocumentSnapshot added with ID: " <<future.result()->id()              <<std::endl;}else{std::cout <<"Error adding document: " <<future.error_message() <<std::endl;}});
snippets.cpp

DocumentReferencedocRef=db.Collection("users").Document("alovelace");Dictionary<string,object>user=newDictionary<string,object>{{"First","Ada"},{"Last","Lovelace"},{"Born",1815},};docRef.SetAsync(user).ContinueWithOnMainThread(task=>{Debug.Log("Added data to the alovelace document in the users collection.");});

// Add a second document with a generated ID.import{addDoc,collection}from"firebase/firestore";try{constdocRef=awaitaddDoc(collection(db,"users"),{first:"Alan",middle:"Mathison",last:"Turing",born:1912});console.log("Document written with ID: ",docRef.id);}catch(e){console.error("Error adding document: ",e);}
add_alan_turing.js

// Add a second document with a generated ID.db.collection("users").add({first:"Alan",middle:"Mathison",last:"Turing",born:1912}).then((docRef)=>{console.log("Document written with ID: ",docRef.id);}).catch((error)=>{console.error("Error adding document: ",error);});
test.firestore.js

// Add a second document with a generated ID.do{letref=tryawaitdb.collection("users").addDocument(data:["first":"Alan","middle":"Mathison","last":"Turing","born":1912])print("Document added with ID:\(ref.documentID)")}catch{print("Error adding document:\(error)")}
ViewController.swift

// Add a second document with a generated ID.__blockFIRDocumentReference*ref=[[self.dbcollectionWithPath:@"users"]addDocumentWithData:@{@"first":@"Alan",@"middle":@"Mathison",@"last":@"Turing",@"born":@1912}completion:^(NSError*_Nullableerror){if(error!=nil){NSLog(@"Error adding document: %@",error);}else{NSLog(@"Document added with ID: %@",ref.documentID);}}];
ViewController.m

// Create a new user with a first, middle, and last namevaluser=hashMapOf("first"to"Alan","middle"to"Mathison","last"to"Turing","born"to1912,)// Add a new document with a generated IDdb.collection("users").add(user).addOnSuccessListener{documentReference->Log.d(TAG,"DocumentSnapshot added with ID:${documentReference.id}")}.addOnFailureListener{e->Log.w(TAG,"Error adding document",e)}
DocSnippets.kt

// Create a new user with a first, middle, and last nameMap<String,Object>user=newHashMap<>();user.put("first","Alan");user.put("middle","Mathison");user.put("last","Turing");user.put("born",1912);// Add a new document with a generated IDdb.collection("users").add(user).addOnSuccessListener(newOnSuccessListener<DocumentReference>(){@OverridepublicvoidonSuccess(DocumentReferencedocumentReference){Log.d(TAG,"DocumentSnapshot added with ID: "+documentReference.getId());}}).addOnFailureListener(newOnFailureListener(){@OverridepublicvoidonFailure(@NonNullExceptione){Log.w(TAG,"Error adding document",e);}});
DocSnippets.java

// Create a new user with a first and last namefinaluser=<String,dynamic>{"first":"Alan","middle":"Mathison","last":"Turing","born":1912};// Add a new document with a generated IDdb.collection("users").add(user).then((DocumentReferencedoc)=>print('DocumentSnapshot added with ID:${doc.id}'));
firestore.dart

db->Collection("users").Add({{"first", FieldValue::String("Alan")},          {"middle", FieldValue::String("Mathison")},          {"last", FieldValue::String("Turing")},          {"born", FieldValue::Integer(1912)}}).OnCompletion([](constFuture<DocumentReference>&future){if(future.error()==Error::kErrorOk){std::cout <<"DocumentSnapshot added with ID: "                  <<future.result()->id() <<std::endl;}else{std::cout <<"Error adding document: " <<future.error_message()                  <<std::endl;}});
snippets.cpp

DocumentReferencedocRef=db.Collection("users").Document("aturing");Dictionary<string,object>user=newDictionary<string,object>{{"First","Alan"},{"Middle","Mathison"},{"Last","Turing"},{"Born",1912}};docRef.SetAsync(user).ContinueWithOnMainThread(task=>{Debug.Log("Added data to the aturing document in the users collection.");});

import{collection,getDocs}from"firebase/firestore";constquerySnapshot=awaitgetDocs(collection(db,"users"));querySnapshot.forEach((doc)=>{console.log(`${doc.id} =>${doc.data()}`);});
get_all_users.js

db.collection("users").get().then((querySnapshot)=>{querySnapshot.forEach((doc)=>{console.log(`${doc.id} =>${doc.data()}`);});});
test.firestore.js

do{letsnapshot=tryawaitdb.collection("users").getDocuments()fordocumentinsnapshot.documents{print("\(document.documentID) =>\(document.data())")}}catch{print("Error getting documents:\(error)")}
ViewController.swift

[[self.dbcollectionWithPath:@"users"]getDocumentsWithCompletion:^(FIRQuerySnapshot*_Nullablesnapshot,NSError*_Nullableerror){if(error!=nil){NSLog(@"Error getting documents: %@",error);}else{for(FIRDocumentSnapshot*documentinsnapshot.documents){NSLog(@"%@ => %@",document.documentID,document.data);}}}];
ViewController.m

db.collection("users").get().addOnSuccessListener{result->for(documentinresult){Log.d(TAG,"${document.id} =>${document.data}")}}.addOnFailureListener{exception->Log.w(TAG,"Error getting documents.",exception)}
DocSnippets.kt

db.collection("users").get().addOnCompleteListener(newOnCompleteListener<QuerySnapshot>(){@OverridepublicvoidonComplete(@NonNullTask<QuerySnapshot>task){if(task.isSuccessful()){for(QueryDocumentSnapshotdocument:task.getResult()){Log.d(TAG,document.getId()+" => "+document.getData());}}else{Log.w(TAG,"Error getting documents.",task.getException());}}});
DocSnippets.java

awaitdb.collection("users").get().then((event){for(vardocinevent.docs){print("${doc.id} =>${doc.data()}");}});
firestore.dart

Future<QuerySnapshot>users=db->Collection("users").Get();users.OnCompletion([](constFuture<QuerySnapshot>&future){if(future.error()==Error::kErrorOk){for(constDocumentSnapshot&document:future.result()->documents()){std::cout <<document <<std::endl;}}else{std::cout <<"Error getting documents: " <<future.error_message()              <<std::endl;}});
snippets.cpp

CollectionReferenceusersRef=db.Collection("users");usersRef.GetSnapshotAsync().ContinueWithOnMainThread(task=>{QuerySnapshotsnapshot=task.Result;foreach(DocumentSnapshotdocumentinsnapshot.Documents){Debug.Log(String.Format("User: {0}",document.Id));Dictionary<string,object>documentDictionary=document.ToDictionary();Debug.Log(String.Format("First: {0}",documentDictionary["First"]));if(documentDictionary.ContainsKey("Middle")){Debug.Log(String.Format("Middle: {0}",documentDictionary["Middle"]));}Debug.Log(String.Format("Last: {0}",documentDictionary["Last"]));Debug.Log(String.Format("Born: {0}",documentDictionary["Born"]));}Debug.Log("Read all data from the users collection.");});

// Allow read/write access to a document keyed by the user's UIDservicecloud.firestore{match/databases/{database}/documents{match/users/{uid}{allowread,write:ifrequest.auth!=null &&request.auth.uid==uid;}}}

// Deny read/write access to all users under any conditionsservicecloud.firestore{match/databases/{database}/documents{match/{document=**}{allowread,write:iffalse;}}}