nodedump

Outputs variables in a visual, easy to read format based on Adobe ColdFusion's CFDump tag. Think of it as console.log on steroids.

Usage no npm install needed!

<script type="module">
  import nodedump from 'https://cdn.skypack.dev/nodedump';
</script>

README

nodedump

Outputs variables in a visual, easy to read format based on Adobe ColdFusion's CFDump tag with enhancements unique to node.js such as the syntax highlighting of functions. Think of it as console.log on steroids.

nodedump works both server and client side.

For example, simply doing nodedump(user) gives us:

nodedump example

The above is a dump of the variable user created like so:

signIn = function(username, password){
    // validate username and password
    if(!validate(username, password))
        return false;
    else 
        updateSession();
    
    // user is signedIn
    this.signedIn = true;
    return true;
};

var user = {
    firstName: 'Charles'
    ,lastName: 'Teague'
    ,age: 21
    ,signedIn: false
    ,signIn: signIn
    ,projects: [
        {
            name: 'Allaire Spectra'
            ,status: 'Horrible death'
        }
        ,{
            name: 'ColdFusion 4.5'
            ,status: 'Been there done that'
        }
    ]
};

With console.log(user) we get:

{ firstName: 'Charles',
  lastName: 'Teague',
  age: 21,
  signedIn: false,
  signIn: [Function],
  projects:
   [ { name: 'Allaire Spectra', status: 'Horrible death' },
     { name: 'ColdFusion 4.5', status: 'Been there done that' } ] }

Which is the typical output we have to rely on usually to do our debugging. As our variables become more complicated this becomes a painful way to know what's going on within them.

nodedump is based on the CFDump tag of Adobe's ColdFusion which has long been a unique feature allowing developers to understand what's in any variable. Once you get accustomed to the color coding and layout of dumped output, your brain will be able to quickly see and understand what's in any variable you dump with just a glance. Pretty much all the options available for CFDump have been included in nodedump.

INSTALLATION

Run this from your bash or command line:

$ [sudo] npm install nodedump

USAGE

First, require nodedump:

require('nodedump');

This will create a global function called nodedump. Then in your view or wherever you output to the browser, whenever you want to dump the contents of a variable do:

nodedump(vartodump);

See the calling nodedump section section for the various ways to call and name the function that is used for dumping.

CLIENT-SIDE

To use nodedump client-side simply include the nodedump-client.js (available in the nodedump-client directory) file in your page and then dump any variable you'd like. For instance:

<!DOCTYPE html>
<html>
<head>
    <title>nodedump client side example</title>
    <script src="nodedump-client-min.js"></script>
</head>
<body>
    <script>
        // dump something
        document.write(nodedump(location));
    </script>
</body>
</html>

EXAMPLE

The following example sets up a server, creates a test object and dumps it to the browser. Try it!

var http = require('http');
nodedump = require('nodedump').dump;

signIn = function(username, password){
    // validate username and password
    if(!validate(username, password))
        return false;
    else 
        updateSession();
    
    // user is signedIn
    this.signedIn = true;
    return true;
};

var server = http.createServer(function(request, response) {
    console.log('Request received',new Date());
    console.log('url:',request.url);
    // skip requests for favicon
    if (request.url.indexOf('favicon.ico') > -1) {
        console.log('favicon requested');
        response.writeHead(500);
        response.end();
        console.log('Request ended');
        return;
    }
    
    // start output to the browser
    response.writeHead(200, {"Content-Type": "text/html"});
    
    var user = {
        firstName: 'Charles'
        ,lastName: 'Teague'
        ,age: 21
        ,signedIn: false
        ,signIn: signIn
        ,projects: [
            {
                name: 'Allaire Spectra'
                , status: 'Horrible death'
            }
            ,{
                name: 'ColdFusion 4.5'
                ,status: 'Been there done that'
            }
        ]
    };
    
    //capture dump
    var output = nodedump(user);
    
    // write response to the browser
    response.write(
        '<html>'
            + '<head>'
                + '<title>nodedump example!</title>'
            + '</head>'
            +'<body>'
                +output
            +'</body>'
        +'</html>'
    );
    response.end();

    console.log('Request ended');
    //console.log('global.bnodedumpinited',global.bnodedumpinited);
}).listen(3000);

console.log("Server has started.");

OPTIONS

Options can be passed as an object whenever you nodedump a variable as the second parameter, e.g. nodedump(vartodump, options)

The available options are:

  • label - String. Output on the header of the dump.
  • expand - Boolean/Array. Defaults to true. The dump can be collapsed entirely by passing false. Simply click on the headers in order to expand them. An array of complex types can be passed and those types of objects will be expanded while everything else will remain collapsed. For e.g. ['Array', 'Object', 'Function']
  • collapse - Boolean/Array. Defaults to false. Works opposite the way expand does. The dump can be collapsed entirely by passing true. An array of types can be passed and those types of objects will be collapsed wherever they are in the dump. For e.g. ['Array', 'Object', 'Function']
  • show - Array. A list of object keys / array positions to show. Others not in the list will be hidden.
  • hide - Array. A list of object keys / array positions to hide.
  • hideTypes - Array. A list of complex types of objects to exclude from being output. e.g. ['RegExp', 'Function'].
  • top - Number. The number of array positions of the dump variable to show. For objects, this is the number of keys of the top level to show.
  • levels - Number. How many nested levels of an object to dump down to.
  • sortKeys - Boolean. Defaults to true. Tells nodedump to output the keys of objects sorted alphabetically. If false, keys will be output in whatever order node.js returns them (usually the order in which they were added).
  • syntaxHighlight - Boolean. Defaults to true. Tells whether or not the dump of functions should be syntax highlighted (color-coded).
  • dumpFunctionName - String. Defaults to 'nodedump'. Name to use for the nodedump function. E.g. if this is changed to 'dump' then in addition to doing nodedump(vartodump) you can do dump(vartodump).

OPTIONS IN ACTION

expand and label

nodedump(user1, {expand: false, label: 'User1'});
nodedump(user2, {expand: false, label: 'User 2'});

Outputs:

nodedump example of 'expand' and 'label' options

Clicking on the header of collapsed sections will expand them.

top with an object

nodedump(user, {top:4});

Outputs:

nodedump example of 'top' with an object

Notice that though the object has 6 keys, only the top 4 were output.

top with an array

nodedump(user.projects, {top:1});

Outputs:

nodedump example of 'top' with an array

levels

nodedump(user, {levels:2});

Outputs:

nodedump example of 'levels' option

Notice that in the projects sub-array that the 3rd level is not shown.

show

nodedump(user, {show:['signedIn','age','lastName']});

Outputs:

nodedump example of 'show' option

hide

nodedump(user, {hide:['projects']});

Outputs:

nodedump example of 'hide' option

OVERRIDING DEFAULT OPTIONS

Default options can be overriden by calling the init method on nodedump. E.g.

require('nodedump').init({
    dumpFunctionName: 'dump'
    ,top: 100
    ,sortKeys: false
    ,expand: false
});

The above would set the default for all nodedumps as follows:

  • You could do dump(vartodump) instead nodedump(vartodump). Keep in mind that the latter would still work.
  • Output no more than 100 top keys.
  • Not sort object keys.
  • Show all nodedumps collapsed.

CALLING NODEDUMP

require('nodedump') will create the global function nodedump that can be used to dump variables. As you've seen with the dumpFunctionName option you can add another name for the function and use that instead. Another way to do this is to set your variable directly to the dump function. E.g.:

d = require('nodedump').dump;

So now you'd be able to dump variables using d(vartodump).

You can do this even when initializing nodedump with default options:

d = require('nodedump').init({ expand: false }).dump;