Cannot define extra entry fields to fetch

[Ryan Hmd]

Hi,
The RSS feed I fetch includes, for each item, an illustration image of the published article. As this field is not provided by default, I have tried to define it in the parser options as explained here in the documentation, but I get the following error when executing my script:

TypeError: Cannot read properties of undefined (reading '@_url')

Here is the definition of my options (I use typescript):

const options = {
    getExtraEntryFields: (entryData: any /* What is the expected type ?? */) => {
        const { enclosure } = entryData
        return {
            enclosure: {
                url: enclosure['@_url'], // enclosure is undefined ...
                type: enclosure['@_type'], // enclosure is undefined ...
            }
        }
    }
}

const rss = await extract(url, options)

I'm new to using RSS feeds, can you help me understand the error and get to the point?

[Ryan Hmd]

Well... I'm a bit embarrassed, but I realized my mistake and solved the problem a few minutes after posting the issue. I naively used the keys from the documentation example, whereas the keys I need to extract are named differently... It's as simple as that.

The corrected script:

const options = {
    getExtraEntryFields: (entryData: any) => {
        const enclosure = entryData['media:content'] // the key I wanted is named 'media:content'
        if (!enclosure) return {}
        return {
            enclosure: {
                url: enclosure['@_url'],
                type: enclosure['@_type']
            }
        }
    }
}

Sorry for opening up this non-issue.

[Dong Nguyen]

@ryan-hmd yes, this lib converts XML document into a JS Object looks like image below. The full object (just call it feedData) will be used for getExtraFeedFields(), while the child items (just call them feedEntry) will be used for getExtraEntryFields().

So getExtraFeedFields can access the whole data, while getExtraEntryFields can help to manipulate every entry.