Move some auth snippets from quickstart-js

auth/anonymous.js

@@ -0,0 +1,19 @@
+// These samples are intended for Web so this import would normally be
+// done in HTML however using modules here is more convenient for
+// ensuring sample correctness offline.
+import firebase from "firebase/app";
+import "firebase/auth";
+
+function anonSignIn() {
+  // [START auth_anon_sign_in]
+  firebase.auth().signInAnonymously()
+    .then(() => {
+      // Signed in..
+    })
+    .catch((error) => {
+      var errorCode = error.code;
+      var errorMessage = error.message;
+      // ...
+    })
+  // [END auth_anon_sign_in]
+}

auth/custom.js

@@ -0,0 +1,21 @@
+// These samples are intended for Web so this import would normally be
+// done in HTML however using modules here is more convenient for
+// ensuring sample correctness offline.
+import firebase from "firebase/app";
+import "firebase/auth";
+
+function signInCustom() {
+  var token = "token123";
+  // [START auth_sign_in_custom]
+  firebase.auth().signInWithCustomToken(token)
+    .then((user) => {
+      // Signed in
+      // ...
+    })
+    .catch((error) => {
+      var errorCode = error.code;
+      var errorMessage = error.message;
+      // ...
+    })
+  // [END auth_sign_in_custom]
+}

auth/email-link-auth.js

@@ -35,9 +35,12 @@ function emailLinkSend(email, actionCodeSettings) {
       // Save the email locally so you don't need to ask the user for it again
       // if they open the link on the same device.
       window.localStorage.setItem('emailForSignIn', email);
+      // ...
     })
     .catch((error) => {
-      // Some error occurred, you can inspect the code: error.code
+      var errorCode = error.code;
+      var errorMessage = error.message;
+      // ...
     });
   // [END auth_email_link_send]
 }

auth/email.js

@@ -0,0 +1,64 @@
+// These samples are intended for Web so this import would normally be
+// done in HTML however using modules here is more convenient for
+// ensuring sample correctness offline.
+import firebase from "firebase/app";
+import "firebase/auth";
+
+function signInWithEmailPassword() {
+  var email = "[email protected]";
+  var password = "hunter2";
+  // [START auth_signin_password]
+  firebase.auth().signInWithEmailAndPassword(email, password)
+    .then((user) => {
+      // Signed in 
+      // ...
+    })
+    .catch((error) => {
+      var errorCode = error.code;
+      var errorMessage = error.message;
+    });
+  // [END auth_signin_password]
+}
+
+function signUpWithEmailPasswoerd() {
+  var email = "[email protected]";
+  var password = "hunter2";
+  // [START auth_signup_password]
+  firebase.auth().createUserWithEmailAndPassword(email, password)
+    .then((user) => {
+      // Signed in 
+      // ...
+    })
+    .catch((error) => {
+      var errorCode = error.code;
+      var errorMessage = error.message;
+      // ..
+    });
+  // [END auth_signup_password]
+}
+
+function sendEmailVerification() {
+  // [START auth_send_email_verification]
+  firebase.auth().currentUser.sendEmailVerification()
+    .then(() => {
+      // Email verification sent!
+      // ...
+    });
+  // [END auth_send_email_verification]
+}
+
+function sendPasswordReset() {
+  const email = "[email protected]";
+  // [START auth_send_password_reset]
+  firebase.auth().sendPasswordResetEmail(email)
+    .then(() => {
+      // Password reset email sent!
+      // ..
+    })
+    .catch((error) => {
+      var errorCode = error.code;
+      var errorMessage = error.message;
+      // ..
+    });
+  // [END auth_send_password_reset]
+}

auth/facebook.js

@@ -0,0 +1,55 @@
+// These samples are intended for Web so this import would normally be
+// done in HTML however using modules here is more convenient for
+// ensuring sample correctness offline.
+import firebase from "firebase/app";
+import "firebase/auth";
+
+// [START auth_facebook_callback]
+function checkLoginState(response) {
+  if (response.authResponse) {
+    // User is signed-in Facebook.
+    var unsubscribe = firebase.auth().onAuthStateChanged((firebaseUser) => {
+      unsubscribe();
+      // Check if we are already signed-in Firebase with the correct user.
+      if (!isUserEqual(response.authResponse, firebaseUser)) {
+        // Build Firebase credential with the Facebook auth token.
+        var credential = firebase.auth.FacebookAuthProvider.credential(
+            response.authResponse.accessToken);
+
+        // Sign in with the credential from the Facebook user.
+        firebase.auth().signInWithCredential(credential).catch((error) => {
+          // Handle Errors here.
+          var errorCode = error.code;
+          var errorMessage = error.message;
+          // The email of the user's account used.
+          var email = error.email;
+          // The firebase.auth.AuthCredential type that was used.
+          var credential = error.credential;
+          // ...
+        });
+      } else {
+        // User is already signed-in Firebase with the correct user.
+      }
+    });
+  } else {
+    // User is signed-out of Facebook.
+    firebase.auth().signOut();
+  }
+}
+// [END auth_facebook_callback]
+
+// [START auth_facebook_checksameuser]
+function isUserEqual(facebookAuthResponse, firebaseUser) {
+  if (firebaseUser) {
+    var providerData = firebaseUser.providerData;
+    for (var i = 0; i < providerData.length; i++) {
+      if (providerData[i].providerId === firebase.auth.FacebookAuthProvider.PROVIDER_ID &&
+          providerData[i].uid === facebookAuthResponse.userID) {
+        // We don't need to re-auth the Firebase connection.
+        return true;
+      }
+    }
+  }
+  return false;
+}
+// [END auth_facebook_checksameuser]

auth/index.js

@@ -4,7 +4,9 @@
 import firebase from "firebase/app";
 import "firebase/auth";
 
-// Docs: https://source.corp.google.com/piper///depot/google3/third_party/devsite/firebase/en/docs/auth/_includes/_get_credentials_web.html
+// ==========================================================================================
+// Docs: Snippets in this file are "general purpose" and are used on more than one docs page
+// ==========================================================================================
 
 function makeGoogleCredential(googleUser) {
   // [START auth_make_google_credential]
@@ -26,8 +28,6 @@ function makeEmailCredential(email, password) {
   // [END auth_make_email_credential]
 }
 
-// Docs: https://source.corp.google.com/piper///depot/google3/third_party/devsite/firebase/en/docs/auth/_includes/_next_steps_web.html
-
 function signOut() {
   // [START auth_sign_out]
   firebase.auth().signOut().then(() => {
@@ -37,3 +37,19 @@ function signOut() {
   });
   // [END auth_sign_out]
 }
+
+function authStateListener() {
+  // [START auth_state_listener]
+  firebase.auth().onAuthStateChanged((user) => {
+    if (user) {
+      // User is signed in, see docs for a list of available properties
+      // https://firebase.google.com/docs/reference/js/firebase.User
+      var uid = user.uid;
+      // ...
+    } else {
+      // User is signed out
+      // ...
+    }
+  });
+  // [END auth_state_listener]
+}