Verify existence of collection in Meteor

One of the challenges I'm facing involves a complex method function that pulls data from various collections. These collections are defined in optional packages within the project. My current task is to determine if a specific collection is defined, indicating whether the package has been added to the project.

I attempted to use an if statement for this purpose, but encountered issues. Despite this effort, I continue to receive the error message Articles is not defined, causing the script to terminate prematurely.

Meteor.methods({
    data: function () {

        if (Articles) {
            Articles.find(
                { parent: null }, 
                { fields: { title: true } } 
            );
        }
    }
});

Answer №1

If the collection is defined as a global variable, there are several methods to check for it securely. You can use the following code snippet:

var main = Meteor.isClient ? window : global;
if (main.Products) {...}

For more information, refer to reference guide on collections.

Answer №2

To verify if something is undefined, the typeof operator comes in handy.

'use strict'; // Ensuring we'll catch a reference error

if (typeof Items === 'undefined') {
  document.querySelector('pre').innerText = 'No items found';
}
<pre>Items?</pre>

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