Feature-request: Transform relative file links #897
Description
Sometimes text is distributed among multiple markdown files, which refer to each other with links such as [Configuration-section](./configuration.md).
When transforming to HTML, it would be nice to link to the corresponding files (./configuration.html in the example above).
While I already have written a RelativeFileLinkExtension and included it in our project, I'd prefer to have it officially supported and would therefore like to create a merge-request for it. Would this be a welcome contribution, @xoofx ?
Code from our project as follows:
public static MarkdownPipelineBuilder TransformFileLinks(this MarkdownPipelineBuilder pipeline)
{
pipeline.Extensions.AddIfNotAlready<RelativeFileLinkExtension>();
return pipeline;
}internal sealed class RelativeFileLinkExtension : IMarkdownExtension
{
/// <inheritdoc/>
public void Setup(MarkdownPipelineBuilder pipeline)
{
// Make sure we do not have a delegate twice
pipeline.DocumentProcessed -= OnDocumentProcessed;
pipeline.DocumentProcessed += OnDocumentProcessed;
}
/// <inheritdoc/>
public void Setup(MarkdownPipeline pipeline, IMarkdownRenderer renderer) { }
private static void OnDocumentProcessed(MarkdownDocument document)
{
foreach (MarkdownObject node in document.Descendants())
{
if (node is not LinkInline link)
{
continue;
}
string? url = link.Url;
if (string.IsNullOrEmpty(url))
{
continue;
}
const string oldExtension = "md";
const string newExtension = "html";
// we only want to modify relative paths linking to other .md files
if (url.StartsWith('.') && url.EndsWith($".{oldExtension}", StringComparison.InvariantCultureIgnoreCase))
{
link.Url = string.Create(url.Length + (newExtension.Length - oldExtension.Length), url, static (chars, source) =>
{
source.AsSpan()[..(source.Length - (newExtension.Length - oldExtension.Length))].CopyTo(chars);
newExtension.AsSpan().CopyTo(chars[^newExtension.Length..]);
});
}
}
}
}