first working or at least useful verion for rtdb

rtdb-get.js

@@ -0,0 +1,39 @@
+
+
+let oldpath
+
+module.exports = function(RED) {
+  function FirebaseAdmin(config) {
+    RED.nodes.createNode(this, config);
+    var node = this;
+
+    console.log('config is..')
+    console.dir(config)
+    if(config.cred){
+      let c = RED.nodes.getNode(config.cred)
+      this.admin = c.admin
+    }
+
+    const cb = (res)=>{
+      console.log('firebase get result '+res)
+      console.dir(res)
+      let val = res.val()
+      console.log('val='+val)
+      node.send({payload:val})
+    }
+
+    node.on('input', function(msg) {
+      if(msg && msg.payload){
+        const path = msg.payload.path
+        if(oldpath){
+          this.admin.database().ref(oldpath).off('value', cb)
+        }
+        this.admin.database().ref(path).on('value', cb)
+        oldpath = path
+      }
+    }.bind(this));
+
+
+  }
+  RED.nodes.registerType("rtdb-get", FirebaseAdmin);
+}