Internationalisation

A node can include a message catalog in order to provide translated content in the editor and runtime.

For each node identified in a module’s package.json, a corresponding set of message catalogs and help files can be included alongside the node’s .js file.

Given a node identified as: “name”: “my-node-module”, “node-red”: { “myNode”: “myNode/my-node.js” }

The following message catalogs may exist:

myNode/locales/__language__/my-node.json
myNode/locales/__language__/my-node.html

The locales directory must be in the same directory as the node’s .js file.

The __language__ part of the path identifies the language the corresponding files provide. By default, Node-RED uses en-US.

Message Catalog

The message catalog is a JSON file containing any pieces of text that the node may display in the editor or log in the runtime.

For example:

{
    "myNode" : {
        "message1": "This is my first message",
        "message2": "This is my second message"
    }
}

The catalog is loaded under a namespace specific to the node. For the node defined above, this catalog would be available under the my-node-module/myNode namespace.

The core nodes use the node-red namespace.

Help Text

The help file provides translated versions of the node’s help text that gets displayed within the Info sidebar tab of the editor.

Using i18n messages

In both the runtime and editor, functions are provided for nodes to look-up messages from the catalogs. These are pre-scoped to the nodes own namespace so it isn’t necessary to include the namespace in the message identifier.

Runtime

The runtime part of a node can access messages using the RED._() function. For example:

console.log(RED._("myNode.message1"));

Status messages

If a node sends status messages to the editor, it should set the text of the status as the message identifier.

this.status({fill:"green",shape:"dot",text:"myNode.status.ready"});

There are a number of commonly used status messages in the core node-red catalog. These can be used by including the namespace in the message identified:

this.status({fill:"green",shape:"dot",text:"node-red:common.status.connected"});

Editor

Any HTML element provided in the node template can specify a data-i18n attribute to provide the message identify to use. For example:

<span data-i18n="myNode.label.foo"></span>

By default, the text content of an element is replace by the message identified. It is also possible to set attributes of the element, such as the placeholder of an <input>:

<input type="text" data-i18n="[placeholder]myNode.placeholder.foo">

It is possible to combine these to specifiy multiple substitutions For example, to set both the title attribute and the displayed text:

<a href="#" data-i18n="[title]myNode.label.linkTitle;myNode.label.linkText"></a>

As well as the data-i18n attribute for html elements, all node definition functions (for example, oneditprepare) can use this._() to retrieve messages.