A go at PATCH implementation

api/database.js

@@ -1,4 +1,5 @@
 const firebase = require('firebase');
+const jsonpatch = require('fast-json-patch');
 
 function guessType(value) {
     const number = /^-?\d*\.?\d*$/;
@@ -37,39 +38,43 @@ if (!process.env.FIREBASE_CONFIG) {
     const config = JSON.parse(process.env.FIREBASE_CONFIG);
     firebase.initializeApp(config);
 
-    module.exports = {
-        get: (key, orderKey, filterValue, valueType) => {
-            let ref = firebase.database().ref(key);
+    function get(key, orderKey, filterValue, valueType) {
+        let ref = firebase.database().ref(key);
 
-            if (orderKey) {
-                ref = ref.orderByChild(orderKey);
-                if (filterValue !== undefined) {
-                    ref = ref.equalTo(convert(filterValue, valueType));
-                }
+        if (orderKey) {
+            ref = ref.orderByChild(orderKey);
+            if (filterValue !== undefined) {
+                ref = ref.equalTo(convert(filterValue, valueType));
             }
-            return ref
-                .once('value')
-                .then(snapshot => {
-                    if (!orderKey) {
-                        return snapshot.val();
+        }
+        return ref
+            .once('value')
+            .then(snapshot => {
+                if (!orderKey) {
+                    return snapshot.val();
+                }
+
+                const data = [];
+                // snapshot.val() forgets any ordering info
+                snapshot.forEach(item => {
+                    if (item.val()) {
+                        data.push(item.val());
                     }
-
-                    const data = [];
-                    // snapshot.val() forgets any ordering info
-                    snapshot.forEach(item => {
-                        if (item.val()) {
-                            data.push(item.val());
-                        }
-                    });
-                    return data;
                 });
-        },
+                return data;
+            });
+    }
 
-        post: (key, data) =>
-            firebase
-                .database()
-                .ref(key)
-                .set(data),
+    function post(key, data) {
+        return firebase
+            .database()
+            .ref(key)
+            .set(data);
+    }
+
+    module.exports = {
+        get,
+        post,
 
         put: (key, data) =>
             firebase
@@ -84,5 +89,17 @@ if (!process.env.FIREBASE_CONFIG) {
                 .database()
                 .ref(key)
                 .remove(),
+
+        patch: (key, data, type) => {
+            return get(key).then(stored => {
+                let patched = null;
+                if (type === 'application/json') {
+                    patched = Object.assign(stored, data);
+                } else if (type === 'application/json-patch+json') {
+                    patched = jsonpatch.applyPatch(stored, data).newDocument;
+                }
+                return post(key, patched);                
+            });
+        },
     }
 }

api/routes.js

@@ -33,7 +33,7 @@ router.post(/^\/[0-9a-z]{64}/, checkContentType, (req, res) =>
         .post(req.path, req.body)
         .then(() => res.status(201).send({ ok: true }))
         .catch(() => res.status(500).send({ ok: false }))
-)
+);
 
 router.put(/^\/[0-9a-z]{64}/, checkContentType, (req, res) =>
     database
@@ -49,4 +49,15 @@ router.delete(/^\/[0-9a-z]{64}/, (req, res) =>
         .catch(() => res.status(500).send({ ok: false }))
 );
 
+router.patch(/^\/[0-9a-z]{64}/, (req, res) =>
+    database
+        .patch(req.path, req.body, req.headers['content-type'])
+        .then(() => res.status(200).send({ ok: true }))
+        .catch((err) => {
+            console.log(err);
+            res.status(500).send({ ok: false });
+        }),
+);
+
 module.exports = router;
+