Add options into select label (attempt to read options from js files)

General
1

A primary question，I defined a label in html file, and want to read options from a certain file (js), how can it be realized?
e.g.,in html,
< script type="text/x-red" data-template-name="">
<select> func</select>
</script>

<script type="text/javascript">
Object.keys(JSfileReturnArray).forEach(function(f) {
func.append($("").val(f).text(f));
})
</script>

2

Evening Qin,

Perhaps I understand this incorrectly, but do you want to show (in your node's config screen) a dropdown with options that you get from the server-side flow (js file)?

If so, in my type-converter node you can see in the html file how I fill a dropdown with options that I get (via an ajax call) from the server side Node-RED flow:

// Load the available categories from the server
$.getJSON('unit-converter/categories', function(data) {
        // Show all available categories in the dropdown
         for (i = 0; i < data.length; i++) {
                var category = data[i];
                $("<option value='" + category + "'> " + category.charAt(0).toUpperCase() + category.slice(1) + "</option>").appendTo("#node-input-category");
         }   
});

And in the js file you can find how the server-side will publish this data:

    // Make all the available types accessible for the node's config screen
    RED.httpAdmin.get('/unit-converter/:cmd', RED.auth.needsPermission('unitconverter.read'), function(req, res){
        var node = RED.nodes.getNode(req.params.id);
        
        if (req.params.cmd === "categories") {
            // Return a list of all available categories (mass, length, ...)
            res.json(your_list_of_categories);
        }
    });

Bart

2 Likes
3

Dear Bart,
Many thanks for your patience and solution.

Basically, your understanding is right. but the js file which will return the options is located on local, not on server-side.

Your solution is very helpful for me. I think I can solve my this issue by referring to your node.

1 Like
4

You cannot generally mix server and local files as that is a severe security issue. If you really need to do something like that, run Node-RED locally as well as on the server and then use the local version to combine data from the server.

5

For anyone who comes here looking for HTML-to-JS comm examples, note that this line in the JS code:

only returns the "node" if the node has been deployed. Otherwise it is "null".

( I don't think it actually is used for anything in the "unit-converter" code. )

6

That's correct. Though there are ways to also capture undeployed nodes via an event listener should you ever need to do that (I did :slight_smile: )