ovlach_pdf/src/routes/pdf.rs

use headless_chrome::Browser;
use headless_chrome::types::PrintToPdfOptions;
use nanobyte_opentelemetry::rocket::TracingSpan;
use rocket::{get, response::stream::ByteStream, fairing::Fairing, fs::NamedFile, futures::TryFutureExt};
use tempfile::NamedTempFile;
use tera::Context;
use tracing::{info_span, error, debug};
use crate::{chromium::rocket::BrowserHolder, tools::{tera::NanoTera, pdf::PdfStream}};
use urlencoding::encode;

// TODO: request-id
fn generate_pdf(browser: Browser, file: &NamedTempFile) -> Vec<u8> {
    let tab = browser.new_tab().unwrap();
    let path = format!("file://{}", file.path().to_str().unwrap());
    info_span!("open_pdf").in_scope(|| {
        debug!("Render pdf from {}", &path);
        tab.navigate_to(&path).unwrap().wait_until_navigated().unwrap();
    });

    let options = PrintToPdfOptions{
        margin_bottom: Some(0.0),
        margin_left: Some(0.0),
        margin_right: Some(0.0),
        margin_top: Some(0.0),
        print_background: Some(true),
        //paper_width: Some(29.7),
        //paper_height: Some(21.0),
        ..PrintToPdfOptions::default()
    };

    //thread::sleep(Duration::from_secs(10)); 

    let bytes = info_span!("print_pdf").in_scope(|| {
         tab.print_to_pdf(Some(options)).unwrap()
    });

    return bytes;
}

#[tracing::instrument]
fn render_template(template_name: &str, file: &NamedTempFile, tera: NanoTera) {
    // TODO: handle errors
    tera.0.render_to("two_column.html.tera", &Context::new(), file);
}

#[get("/cv/<username>/output.pdf")]
pub async fn render_pdf_cv(username: &str, browser: BrowserHolder, tera: NanoTera, tracing: TracingSpan) -> PdfStream { 
    let entered_span = tracing.0.enter();
    let file = tempfile::Builder::new().suffix(".html").tempfile().unwrap(); 
    render_template("two_column", &file, tera);
    let span = info_span!("render_pdf", username = username);
    let pdf = span.in_scope(||{
        generate_pdf(browser.browser, &file)
    });
    drop(entered_span);
    PdfStream::new(pdf)
}

/// Route only for debuging
#[get("/cv/<username>/output.html")]
pub async fn render_html_cv(username: &str, tera: NanoTera, tracing: TracingSpan) -> NamedFile { 
    let entered_span = tracing.0.enter();
    let file = tempfile::Builder::new().suffix(".html").tempfile().unwrap(); 
    render_template("two_column", &file, tera);
    NamedFile::open(file.path()).await.unwrap()
}