dynamic database name

Feature: database name can be dynamicaly provided as string oder context variable on "mongo in" and "mongo out"

storage/mongodb/66-mongodb.html

@@ -51,7 +51,7 @@
             topology: {value: "direct", required: true},
             connectOptions: {value: "", required: false},
             port: {value: 27017, required: true},
-            db: {value: "", required: true},
+            db: {value: "", required: false},
             name: {value: ""}
         },
         credentials: {
@@ -74,11 +74,53 @@
     });
 </script>
 
+<script type="text/html" data-help-name="mongodb">
+    <p>Define a connection method to your MongoDB server instance.</p>
+    <p>There are 3 supported options:
+        <details><summary>Standard/direct</summary>
+            For databases that request connections in the form
+            <code>
+              mongodb://[username]:[password]@[hostname]:[port]/[dbname]
+            </code>
+            Most often used for local MongoDB instances (localhost:27017), and other stand-alone instances.
+        </details>
+        <details><summary>Standard/replicaset</summary>
+            For databases that request connections in the form
+            <code>
+            mongodb://[username]:[password]@[hostnameA]:[port],[hostnameB]:[port]/[dbname]?replicaSet=[replsetname]
+            </code>
+            Often used with <q>database as a service</q> offerings,
+            or on-premises instances that have been configured for availability and resilience
+        </details>
+        <details><summary>Clustered by DNS seedlist</summary>
+            For databases that request connections in the form
+            <code>
+            mongodb+srv://[username]:[password]@[clustername]/[dbname]?retryWrites=true&w=majority
+            </code>
+            A configuration of MongoDB instances that provide availability and performance
+            through replication and sharding, accessed through a cluster alias name, rather than
+            by specific host:port connections. This is the default for MongoDB instances in the
+            <a href="https://www.mongodb.com/cloud/atlas" target="_blank">Atlas cloud service</a>.
+        </details>
+      <p><strong>Connect options</strong> is where you add the optional parameters required by your MongoDB instance.
+        This might include:
+        <ul><li>w=majority</li><li>replicaSet=replset</li><li>authSource=admin</li></ul> and any other options appropriate -
+        full set available at <a href="https://docs.mongodb.com/manual/reference/connection-string/" target="_blank">
+        Connection String URI Format — MongoDB Manual</a>.
+      <p>If you are connecting to <a href="https://cloud.ibm.com/catalog/services/databases-for-mongodb-group" target="_blank">
+        IBM Databases for MongoDB</a>, as a replica-set, be sure to append <code>ssl=true&tlsAllowInvalidCertificates=true </code>
+        to the <strong>Connect options</strong>.
+</script>
+
 <script type="text/html" data-template-name="mongodb out">
     <div class="form-row">
         <label for="node-input-mongodb"><i class="fa fa-bookmark"></i> <span data-i18n="mongodb.label.server"></span></label>
         <input type="text" id="node-input-mongodb">
     </div>
+    <div class="form-row">
+        <label for="node-input-db"><i class="fa fa-database"></i> <span data-i18n="mongodb.label.database"></span></label>
+        <input type="text" id="node-input-dbname">
+    </div>
     <div class="form-row">
         <label for="node-input-collection"><i class="fa fa-briefcase"></i> <span data-i18n="mongodb.label.collection"></span></label>
         <input type="text" id="node-input-collection">
@@ -114,8 +156,36 @@
     <div class="form-tips" id="node-warning" style="display: none"><span data-i18n="[html]mongodb.tip"></span></div>
 </script>
 
+<script type="text/html" data-help-name="mongodb out">
+    <p>A simple MongoDB output node. Can save, insert, update and remove objects from a chosen collection.</p>
+    <p>Save will update an existing object or insert a new object if one does not already exist.</p>
+    <p>Insert will insert a new object.</p>
+    <p>Save and insert either store <code>msg</code> or <code>msg.payload</code>.</p>
+    <p>Update will modify an existing object or objects. The query to select objects to update uses <code>msg.query</code>
+    and the update to the element uses <code>msg.payload</code>. If <code>msg.query._id</code> is
+    a valid mongo ObjectId string it will be converted to an ObjectId type.</p>
+    <p>Update can add a object if it does not exist or update multiple objects.</p>
+    <p>Remove will remove objects that match the query passed in on <code>msg.payload</code>. A blank query will delete
+    <i>all of the objects</i> in the collection.</p>
+    <p>You can either use the database given in mongodb config or provide a database name or a context variable where
+    the database name should be loaded from. Before getting the collection, database will be switched to the given.</p>
+    <p>You can either set the collection method in the node config or on <code>msg.collection</code>. Setting it in the
+    node will override <code>msg.collection</code>.</p>
+    <p>By default MongoDB creates an <i>_id</i> property as the primary key - so repeated injections of the
+    same <code>msg</code> will result in many database entries.</p>
+    <p>If this is NOT the desired behaviour - ie. you want repeated entries to overwrite, then you must set
+    the <code>msg._id</code> property to be a constant by the use of a previous function node.</p>
+    <p>This could be a unique constant or you could create one based on some other msg property.</p>
+    <p>Currently we do not limit or cap the collection size at all... this may well change.</p>
+</script>
+
 <script type="text/javascript">
     function oneditprepare() {
+        $("#node-input-dbname").typedInput({
+          default: this.dbnameType||'str',
+          types: ["str", "msg", "flow", "global"]
+        });
+
         $("#node-input-operation").change(function () {
             var id = $("#node-input-operation option:selected").val();
 
@@ -137,7 +207,11 @@
                 $("#node-warning").hide();
             }
         });
-    }
+    };
+
+    function oneditsave() {
+      this.dbnameType = $("#node-input-dbname").typedInput('type');
+    };
 
     RED.nodes.registerType('mongodb out', {
         category: 'storage-output',
@@ -145,6 +219,8 @@
         defaults: {
             mongodb: {type: "mongodb", required: true},
             name: {value: ""},
+            dbname: {value: "", required: false, validate: RED.validators.typedInput("dbnameType")},
+            dbnameType: {value: "str"},
             collection: {value: ""},
             payonly: {value: false},
             upsert: {value: false},
@@ -162,15 +238,21 @@
         labelStyle: function() {
             return this.name ? "node_label_italic" : "";
         },
-        oneditprepare: oneditprepare
+        oneditprepare: oneditprepare,
+        oneditsave: oneditsave
     });
 </script>
 
+
 <script type="text/html" data-template-name="mongodb in">
     <div class="form-row">
         <label for="node-input-mongodb"><i class="fa fa-bookmark"></i> <span data-i18n="mongodb.label.server"></span></label>
         <input type="text" id="node-input-mongodb">
     </div>
+    <div class="form-row">
+        <label for="node-input-db"><i class="fa fa-database"></i> <span data-i18n="mongodb.label.database"></span></label>
+        <input type="text" id="node-input-dbname">
+    </div>
     <div class="form-row">
         <label for="node-input-collection"><i class="fa fa-briefcase"></i> <span data-i18n="mongodb.label.collection"></span></label>
         <input type="text" id="node-input-collection">
@@ -190,6 +272,23 @@
     <div class="form-tips" id="node-warning" style="display: none"><span data-i18n="[html]mongodb.tip"></span></div>
 </script>
 
+<script type="text/html" data-help-name="mongodb in">
+    <p>Calls a MongoDB collection method based on the selected operator.</p>
+    <p>Find queries a collection using the <code>msg.payload</code> as the query statement as per the .find() function.
+    Optionally, you may also (via a function) set a <code>msg.projection</code> object to constrain the returned
+    fields, a <code>msg.sort</code> object, a <code>msg.limit</code> number and a <code>msg.skip</code> number.</p>
+    <p>Count returns a count of the number of documents in a collection or matching a query using the
+    <code>msg.payload</code> as the query statement.</p>
+    <p>Aggregate provides access to the aggregation pipeline using the <code>msg.payload</code> as the pipeline array.</p>
+    <p>You can either use the database given in mongodb config or provide a database name or a context variable where
+    the database name should be loaded from. Before getting the collection, database will be switched to the given.</p>
+    <p>You can either set the collection method in the node config or on <code>msg.collection</code>. Setting it in
+    the node will override <code>msg.collection</code>.</p>
+    <p>See the <a href="http://docs.mongodb.org/manual/reference/method/db.collection.find/" target="new"><i>MongoDB
+    collection methods docs</i></a> for examples.</p>
+    <p>The result is returned in <code>msg.payload</code>.</p>
+</script>
+
 <script type="text/javascript">
     RED.nodes.registerType('mongodb in', {
         category: 'storage-input',
@@ -197,6 +296,8 @@
         defaults: {
             mongodb: {type: "mongodb", required: true},
             name: {value: ""},
+            dbname: {value: "", required: false, validate: RED.validators.typedInput("dbnameType")},
+            dbnameType: {value: "str"},
             collection: {value: ""},
             operation: {value: "find"}
         },
@@ -210,6 +311,7 @@
         labelStyle: function() {
             return this.name ? "node_label_italic" : "";
         },
-        oneditprepare: oneditprepare
+        oneditprepare: oneditprepare,
+        oneditsave: oneditsave
     });
 </script>

storage/mongodb/66-mongodb.js

@@ -18,6 +18,7 @@ module.exports = function(RED) {
         //console.log(this);
 
         var clustered = (this.topology !== "direct") || false;
+        var dyndb = (!this.db || this.db.length === 0) || false;
 
         var url = "mongodb://";
         if (this.topology === "dnscluster") {
@@ -34,9 +35,11 @@ module.exports = function(RED) {
             url += this.user+":"+this.password+"@";
         }
         if (clustered) {
-            url += this.hostname + "/" + this.db
+            url += this.hostname + "/";
+            if (!dyndb) url += this.db;
         } else {
-            url += this.hostname + ":" + this.port + "/" + this.db;
+            url += this.hostname + ":" + this.port + "/";
+            if (!dyndb) url += this.db;
         }
         if (this.connectOptions){
             url += "?" + this.connectOptions;
@@ -63,6 +66,8 @@ module.exports = function(RED) {
     function MongoOutNode(n) {
         RED.nodes.createNode(this,n);
         this.collection = n.collection;
+        this.dbname = n.dbname;
+        this.dbnameType = n.dbnameType;
         this.mongodb = n.mongodb;
         this.payonly = n.payonly || false;
         this.upsert = n.upsert || false;
@@ -84,7 +89,20 @@ module.exports = function(RED) {
                 else {
                     node.status({fill:"green",shape:"dot",text:RED._("mongodb.status.connected")});
                     node.client = client;
-                    var db = client.db();
+                    var db = null;
+                    if (node.dbname && node.dbname.length > 0) {
+                      if (node.dbnameType === 'msg' || node.dbnameType === 'flow' || node.dbnameType === 'global') {
+                        var result_dbname = RED.util.evaluateNodeProperty(node.dbname);
+                        node.log("use db " + result_dbname + " from " + node.dbnameType + "." + node.dbname);
+                        db = client.db(result_dbname);
+                      } else {
+                        node.log("use db " + result_dbname + " from " + node.dbname);
+                        db = client.db(node.dbname)
+                      }
+                    } else {
+                      db = client.db()
+                    }
+                    node.log("active db " + db);
                     //console.log( db);
                     noerror = true;
                     var coll;
@@ -194,6 +212,8 @@ module.exports = function(RED) {
     function MongoInNode(n) {
         RED.nodes.createNode(this,n);
         this.collection = n.collection;
+        this.dbname = n.dbname;
+        this.dbnameType = n.dbnameType;
         this.mongodb = n.mongodb;
         this.operation = n.operation || "find";
         this.mongoConfig = RED.nodes.getNode(this.mongodb);
@@ -201,7 +221,21 @@ module.exports = function(RED) {
         var node = this;
         var noerror = true;
 
-        var connectToDB = function() {
+        function getDbname(node,msg,done) {
+            if (node.dbnameType === 'str') {
+                done(node.dbname, msg);
+            } else {
+                RED.util.evaluateNodeProperty(node.dbname,node.dbnameType,node,msg,(err,value) => {
+                    if (err) {
+                        done(undefined,msg);
+                    } else {
+                        done(value,msg);
+                    }
+                });
+            }
+        }
+
+        var connectToServer = function() {
             console.log("connecting:  " + node.mongoConfig.url);
             MongoClient.connect(node.mongoConfig.url, function(err,client) {
                 if (err) {
@@ -213,10 +247,18 @@ module.exports = function(RED) {
                 else {
                     node.status({fill:"green",shape:"dot",text:RED._("mongodb.status.connected")});
                     node.client = client;
-                    var db = client.db();
                     noerror = true;
                     var coll;
                     node.on("input", function(msg) {
+                        getDbname(node, msg, function(result_dbname, msg) {
+                            var db;
+                            if (typeof(result_dbname) !== 'unundefined') {
+                              node.log("use db " + result_dbname);
+                              db = client.db(result_dbname);
+                            } else {
+                              node.log("use db from url " + node.mongoConfig.url);
+                              db = client.db();
+                            }
                             if (!node.collection) {
                               if (msg.collection) {
                                 coll = db.collection(msg.collection);
@@ -293,6 +335,107 @@ module.exports = function(RED) {
                               });
                             }
                         });
+                    });
+                }
+            });
+        }
+
+        var connectToDB = function() {
+            console.log("connecting:  " + node.mongoConfig.url);
+            MongoClient.connect(node.mongoConfig.url, function(err,client) {
+                if (err) {
+                    node.status({fill:"red",shape:"ring",text:RED._("mongodb.status.error")});
+                    if (noerror) { node.error(err); }
+                    noerror = false;
+                    node.tout = setTimeout(connectToDB, 10000);
+                }
+                else {
+                    node.status({fill:"green",shape:"dot",text:RED._("mongodb.status.connected")});
+                    node.client = client;
+                    noerror = true;
+                    var coll;
+                    node.on("input", function(msg) {
+                      getDbname(node, msg, function(result_dbname, msg) {
+                          var db;
+                          if (typeof(result_dbname) !== 'unundefined') db = client.db(result_dbname);
+                          else db = client.db();
+                          if (!node.collection) {
+                              if (msg.collection) {
+                                  coll = db.collection(msg.collection);
+                              }
+                              else {
+                                  node.error(RED._("mongodb.errors.nocollection"));
+                                  return;
+                              }
+                          }
+                          else {
+                              coll = db.collection(node.collection);
+                          }
+                          var selector;
+                          if (node.operation === "find") {
+                              msg.projection = msg.projection || {};
+                              selector = ensureValidSelectorObject(msg.payload);
+                              var limit = msg.limit;
+                              if (typeof limit === "string" && !isNaN(limit)) {
+                                  limit = Number(limit);
+                              } else if (typeof limit === "undefined") {
+                                  limit = 0;
+                              }
+                              var skip = msg.skip;
+                              if (typeof skip === "string" && !isNaN(skip)) {
+                                  skip = Number(skip);
+                              } else if (typeof skip === "undefined") {
+                                  skip = 0;
+                              }
+
+                              coll.find(selector).project(msg.projection).sort(msg.sort).limit(limit).skip(skip).toArray(function(err, items) {
+                                  if (err) {
+                                      node.error(err);
+                                  }
+                                  else {
+                                      msg.payload = items;
+                                      delete msg.projection;
+                                      delete msg.sort;
+                                      delete msg.limit;
+                                      delete msg.skip;
+                                      node.send(msg);
+                                  }
+                              });
+                          }
+                          else if (node.operation === "count") {
+                              selector = ensureValidSelectorObject(msg.payload);
+                              coll.count(selector, function(err, count) {
+                                  if (err) {
+                                      node.error(err);
+                                  }
+                                  else {
+                                      msg.payload = count;
+                                      node.send(msg);
+                                  }
+                              });
+                          }
+                          else if (node.operation === "aggregate") {
+                              msg.payload = (Array.isArray(msg.payload)) ? msg.payload : [];
+                              coll.aggregate(msg.payload, function(err, cursor) {
+                                  if (err) {
+                                      node.error(err);
+                                  }
+                                  else {
+                                       cursor.toArray(function(cursorError, cursorDocs) {
+                                         //console.log(cursorDocs);
+                                         if (cursorError) {
+                                           node.error(cursorError);
+                                         }
+                                         else {
+                                           msg.payload = cursorDocs;
+                                           node.send(msg);
+                                         }
+                                       });
+                                  }
+                              });
+                          }
+                      });
+                    });
                 }
             });
         }

storage/mongodb/package.json

@@ -1,18 +1,18 @@
 {
-    "name"          : "node-red-node-mongodb",
+  "name": "node-red-node-mongodb",
-    "version"       : "0.2.5",
+  "version": "0.2.6",
-    "description"   : "Node-RED nodes to talk to a Mongo database",
+  "description": "Node-RED nodes to talk to a Mongo database",
-    "dependencies"  : {
+  "dependencies": {
-        "mongodb"   : "^3.6.3"
+    "mongodb": "^3.6.3"
   },
-    "repository" : {
+  "repository": {
-        "type":"git",
+    "type": "git",
-        "url":"https://github.com/node-red/node-red-nodes/tree/master/storage/mongodb"
+    "url": "https://github.com/node-red/node-red-nodes/tree/master/storage/mongodb"
   },
   "license": "Apache-2.0",
   "keywords": [ "node-red", "mongodb" ],
-    "node-red"      : {
+  "node-red": {
-        "nodes"     : {
+    "nodes": {
       "mongo": "66-mongodb.js"
     }
   },