Artwork download logic in Vala I'd like to have most of logics in GTK-style. It technically is possible to do in Zig, but doing that in Vala is more straightforward and requires less effort, I guess. As a result, overall display speed massively improved.

Changes

4 changed files (+73/-26)

• build.zig
  • @@ -107,6 +107,7 @@ // Neither GTK4 nor Libadwaita provides SVG rendering. We need to use librsvg for
    // that purpose, whilst undocumented. "librsvg-2.0", "gee-0.8", + "libsoup-3.0", }; // A directory containing C source files compiled from Vala source code.
• nix/package.nix
  • @@ -24,6 +24,7 @@ lib,
    libjpeg, libadwaita, librsvg, + libsoup_3, libgee, vala, coreutils,
  • @@ -96,6 +97,11 @@ # Necessary library to use collection types such as HashMap and ArrayList in Vala.
    # https://wiki.gnome.org/Projects/Libgee # https://valadoc.org/gee-0.8/index.htm libgee + + # > HTTP client/server library for GNOME + # https://gitlab.gnome.org/GNOME/libsoup + # https://valadoc.org/libsoup-3.0/index.htm + libsoup_3 # This helper takes care of GLib/GTK's messy runtime things. # https://nixos.org/manual/nixpkgs/stable/#sec-language-gnome
• src/Plac.vala
  • @@ -250,5 +250,9 @@
    yield; return (owned) result; } + + public string? get_image_url(string image_key, Image.GetOptions options) { + return conn.get_image_url(image_key, options); + } } }
• src/Widgets/Artwork.vala
  • @@ -15,7 +15,27 @@ //
    // SPDX-License-Identifier: Apache-2.0 namespace PlacGtkAdwaita { + [SingleInstance] + private class ArtworkDownloader : Object { + public Soup.Session session = new Soup.Session.with_options( + "max_conns", 6, + "max_conns_per_host", 6, + "user_agent", "plac-for-gtk4/0.0 " + ); + + // This class does not use Soup's cache feature: it's undocumented, + // obscure usage (due both to API design and lack of documentation,) + // and frequently crashes. As Roon Server seems to handle our current + // request size/window/rate, this class avoids dealing with libsoup's + // cache. + public ArtworkDownloader() { + Object(); + } + } + class Artwork : Gtk.Box { + private ArtworkDownloader downloader = new ArtworkDownloader(); + private uint16 _width = 100; public uint16 width { get { return _width; }
  • @@ -113,37 +133,53 @@ var opts = new Plac.Image.GetOptions();
    opts.set_size(scaling, _width, _height); opts.set_content_type(JPEG); - _conn.get_image.begin(_image_key, opts, (obj, res) => { - var result = _conn.get_image.end(res); - if (result == null) { - GLib.log("Plac", LEVEL_WARNING, "Failed to download image: Out of memory"); - error_icon.visible = true; - spinner.visible = false; - return; - } + GLib.Uri url; + try { + var raw = _conn.get_image_url(_image_key, opts); + if (raw == null) { + GLib.log("Plac", LEVEL_WARNING, "Failed to build image download URL for %s", _image_key); + error_icon.visible = true; + spinner.visible = false; + return; + } - if (result.code != OK) { - GLib.log("Plac", LEVEL_WARNING, "Failed to download image: %s", result.code.to_string()); - error_icon.visible = true; - spinner.visible = false; - return; - } + url = GLib.Uri.parse(raw, NONE); + } catch (GLib.UriError error) { + GLib.log("Plac", LEVEL_WARNING, "Failed to build image download URL for %s: %s", _image_key, error.message); + error_icon.visible = true; + spinner.visible = false; + return; + } - if (result.image == null) { - GLib.log("Plac", LEVEL_WARNING, "Failed to download image: image_field_missing"); - error_icon.visible = true; - spinner.visible = false; - return; - } + var msg = new Soup.Message.from_uri("GET", url); - var bytes = GLib.Bytes.new_with_owner(result.image.data, result.image); + downloader.session.send_and_read_async.begin(msg, 0, null, (obj, res) => { try { - var texture = Gdk.Texture.from_bytes(bytes); - picture.paintable = texture; - spinner.visible = false; - picture.visible = true; + var bytes = downloader.session.send_and_read_async.end(res); + + // We don't cache, so 3xx response is error here + if (msg.status_code != 200) { + GLib.log("Plac", LEVEL_WARNING, "Failed to download artwork: HTTP %u (key=%s)", msg.status_code, _image_key); + error_icon.visible = true; + spinner.visible = false; + return; + } + + try { + var texture = Gdk.Texture.from_bytes(bytes); + picture.paintable = texture; + spinner.visible = false; + picture.visible = true; + } catch (GLib.Error error) { + GLib.log("Plac", LEVEL_WARNING, "Failed to generate artwork texture: %s", error.message); + error_icon.visible = true; + spinner.visible = false; + } } catch (GLib.Error error) { - GLib.log("Plac", LEVEL_WARNING, "Failed to generate artwork texture: %s", error.message); + GLib.log("Plac", LEVEL_WARNING, "Failed to download image: %s", error.message); + error_icon.visible = true; + spinner.visible = false; + return; } }); }