Swift package for generating a PDF file from a URL (rendered by WebKit).
import Webster
guard let source_url = URL(string: "https://example.com") else {
fatalError("Invalid source URL.")
}
let w = Webster()
w.dpi = 72.0
w.width = 11.0
w.height = 8.5
w.margin = 0.5
on_complete = func(result: Result<Data, Error) -> Void {
if case .failure(let error) = result {
fatalError("Failed to generate PDF file, \(error.localizedDescription)")
}
if case .success(let data) = result {
// Do something with data here
}
}
w.render(source: source_url, completionHandler: on_complete)
This package uses deprecated APIs notably WebView.
Specifically, this package is uses NSPrintOperation to render a WebView. Ideally I would like NSPrintOperation to print directly to a Data instance but it's not possible to do this. Instead the render method creates a temporary file, writes to it, reads the data and removes the temporary file on exit. This introduces extra overhead but, hopefully, keeps the interface a little more agnostic about how the resultant PDF document is used.
There is a wkwebview branch that uses the newer WKWebView APIs however it does not work. I can not determine for sure if the problem is with my code or with Apple's MacOS APIs. It seems like the latter but I would be happy for it to be the former. This branch has two separate delegates, neither of which work as desired.
The first calls webView.printOperation as recommended by the documentation. However when the printOperation.run() method is invoked it never completes. Apparently, I am supposed to invoke the printOperation.runModal method but that depends on a NSWindow instance which is not present in the final webView instance.
The second calls webView.createPDF as recommended by the documentation but this produces a single PDF file the size of the final web page's dimensions. Maybe this is the expected behaviour?
Any pointers or suggestions for how to address either of these issues would be welcome.
This build's on @msmollin's original webster and currently exists as a separate project because it is full of Swift Package Manager -isms and I am not sure what the best way to create a PR is yet.