How to change image URLs in a markdown string
I was trying to see if moving my blog (based on Hugo) to Next.js was a good move (it wasn’t) and I found a problem.
Hugo allows me to use spaces in images, which is handy especially as I use screenshots and I get those named as Screen Shot 2022-...
by default.
The Next.js markdown does not allow that. So I had a script that converted all images names to use hyphens instead of spaces
"Screen Shot 2022-..."
=>
"Screen-Shot-2022-..."
and then I replaced the post markdown content with that.
Also I had to change the URL because Hugo allows a post to be in the same folder as the markdown file, while Next.js does not.
So I used a /public/images/<SLUG>/
folder format to make each post image public.
Here’s how I did that:
import matter from 'gray-matter'
...
let { data: frontmatter, content } = matter(fileName)
const regex = /\!\[(.*?)\]\((.*?)\)/gm
let matches
while ((matches = regex.exec(content)) !== null) {
content = content.replace(
'](' + matches[2],
`](/images/${slug}/${matches[2].replace(/ /g, '-').replace(/\//g, '')}`
)
}
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