Inline HTML

NewDocumentFromString takes markup you already have in memory. Use it when the HTML is generated in your program, which covers most report and invoice work: you run a text/template, and the result goes straight to UniHTML without a temporary file.

doc, err := unihtml.NewDocumentFromString(htmlContent)
if err != nil {
    return err
}
if err := doc.WriteToFile("out.pdf"); err != nil {
    return err
}

That is the whole difference from the other input kinds. Everything after construction is identical.

Assets have nothing to resolve against

An inline string is sent to the server on its own, with no surrounding directory, so a relative path in the markup cannot be resolved. <img src="logo.png"> renders as a broken-image placeholder and no error is returned.

Two things work. Absolute https URLs are fetched by the browser as usual, which needs the container to have outbound network access. Data URIs are self-contained and need nothing:

html := fmt.Sprintf(`<img src="data:image/png;base64,%s">`,
    base64.StdEncoding.EncodeToString(logoBytes))

Inline <style> blocks and style attributes are part of the string and always apply. Only external references are affected.

If your markup needs a tree of local CSS, images or scripts, write it to a directory and use asset directory instead.

Limitations

Rendering starts once the DOM has loaded. Markup that draws itself with JavaScript after that point captures as empty unless you wait for it, which is what wait for rendering covers.

Backgrounds do print. background-color and background-image both appear in the output, which surprises people who have wired up headless Chrome themselves: the print dialog and the DevTools protocol default both suppress them.

There is no size limit imposed by the client. The server holds an upload in memory below 1MB and spills to disk above that, and expires it after three minutes.

Run the example

simple-html-content.go holds a short document in a raw string literal, converts it through a creator.Creator with c.Draw, and writes simple-from-text.pdf.

Note that c.Draw is the one output path that drops link annotations. This example has no links, so it does not matter here; see links if yours does.

git clone https://github.com/unidoc/unihtml-examples.git
cd unihtml-examples/simple
go run simple-html-content.go localhost:8080

If this is your first time using UniHTML, follow the getting started guide to create an API key and set up your development environment.

Sample output