Add extend-woth-functions snippets (#12)

Author: samtstern

firestore/extend-with-functions/functions/index.js

@@ -0,0 +1,162 @@
+const functions = require('firebase-functions');
+
+function triggerSpecificDocument() {
+    // [START trigger_specific_document]
+    // Listen for any change on document `marie` in collection `users`
+    exports.myFunctionName = functions.firestore
+        .document('users/marie').onWrite((event) => {
+            // ... Your code here
+        });
+    // [END trigger_specific_document]
+}
+
+function triggerNewDocument() {
+    // [START trigger_new_document]
+    exports.createUser = functions.firestore
+        .document('users/{userId}')
+        .onCreate(event => {
+            // Get an object representing the document
+            // e.g. {'name': 'Marie', 'age': 66}
+            const newValue = event.data.data();
+
+            // access a particular field as you would any JS property
+            const name = newValue.name;
+
+            // perform desired operations ...
+        });
+    // [END trigger_new_document]
+}
+
+function triggerDocumentUpdated() {
+    // [START trigger_document_updated]
+    exports.updateUser = functions.firestore
+        .document('users/{userId}')
+        .onUpdate(event => {
+            // Get an object representing the document
+            // e.g. {'name': 'Marie', 'age': 66}
+            const newValue = event.data.data();
+
+            // ...or the previous value before this update
+            const previousValue = event.data.previous.data();
+
+            // access a particular field as you would any JS property
+            const name = newValue.name;
+
+            // perform desired operations ...
+        });
+    // [END trigger_document_updated]
+}
+
+function triggerDocumentDeleted() {
+    // [START trigger_document_deleted]
+    exports.deleteUser = functions.firestore
+        .document('users/{userID}')
+        .onDelete(event => {
+            // Get an object representing the document prior to deletion
+            // e.g. {'name': 'Marie', 'age': 66}
+            const deletedValue = event.data.previous.data();
+
+            // perform desired operations ...
+        });
+    // [END trigger_document_deleted]
+}
+
+function triggerDocumentAnyChange() {
+    // [START trigger_document_any_change]
+    exports.modifyUser = functions.firestore
+        .document('users/{userID}')
+        .onWrite(event => {
+            // Get an object with the current document value.
+            // If the document does not exist, it has been deleted.
+            const document = event.data.exists ? event.data.data() : null;
+
+            // Get an object with the previous document value (for update or delete)
+            const oldDocument = event.data.previous.data();
+
+            // perform desired operations ...
+        });
+    // [END trigger_document_any_change]
+}
+
+function readingData() {
+    // [START reading_data]
+    exports.updateUser = functions.firestore
+        .document('users/{userId}')
+        .onUpdate(event => {
+            // Get an object representing the current document
+            const newValue = event.data.data();
+
+            // ...or the previous value before this update
+            const previousValue = event.data.previous.data();
+        });
+    // [END reading_data]
+}
+
+function readingDataWithGet(event) {
+    // [START reading_data_with_get]
+    // Fetch data using standard accessors
+    const age = event.data.data().age;
+    const name = event.data.data()['name'];
+
+    // Fetch data using built in accessor
+    const experience = event.data.get('experience');
+    // [END reading_data_with_get]
+}
+
+function writingData() {
+    // [START writing_data]
+    // Listen for updates to any `user` document.
+    exports.countNameChanges = functions.firestore
+        .document('users/{userId}')
+        .onUpdate((event) => {
+            // Retrieve the current and previous value
+            const data = event.data.data();
+            const previousData = event.data.previous.data();
+
+            // We'll only update if the name has changed.
+            // This is crucial to prevent infinite loops.
+            if (data.name == previousData.name) return;
+
+            // Retrieve the current count of name changes
+            let count = data.name_change_count;
+            if (!count) {
+                count = 0;
+            }
+
+            // Then return a promise of a set operation to update the count
+            return event.data.ref.set({
+                name_change_count: count + 1
+            }, {merge: true});
+        });
+    // [END writing_data]
+}
+
+function basicWildcard() {
+    // [START basic_wildcard]
+    // Listen for changes in all documents and all sub-collections
+    exports.useWildcard = functions.firestore
+        .document('users/{userId}')
+        .onWrite((event) => {
+            // If we set `/users/marie` to {name: "marie"} then
+            // event.params.userId == "marie"
+            // ... and ...
+            // event.data.data() == {name: "Marie"}
+        });
+    // [END basic_wildcard]
+}
+
+function multiWildcard() {
+    // [START multi_wildcard]
+    // Listen for changes in all documents and all subcollections
+    exports.useMultipleWildcards = functions.firestore
+        .document('users/{userId}/{messageCollectionId}/{messageId}')
+        .onWrite((event) => {
+            // If we set `/users/marie/incoming_messages/134` to {body: "Hello"} then
+            // event.params.userId == "malcolm";
+            // event.params.messageCollectionId == "incoming_messages";
+            // event.params.messageId == "134";
+            // ... and ...
+            // event.data.data() == {body: "Hello"}
+        });
+    // [END multi_wildcard]
+}

firestore/extend-with-functions/package.json

@@ -0,0 +1,10 @@
+{
+  "name": "extend-with-functions",
+  "description": "Cloud Functions and Firestore",
+  "main": "index.js",
+  "dependencies": {
+    "firebase-functions": "^0.8.1",
+    "firebase-admin": "^5.4.0",
+    "@google-cloud/firestore": "^0.8.0"
+  }
+}

lerna.json

@@ -2,6 +2,7 @@
   "lerna": "2.8.0",
   "packages": [
     "firestore/main",
+    "firestore/extend-with-functions",
     "firestore/full-text-search",
     "firestore/presence",
     "auth"