Add modules/server/containers/apps/favicon.nix

modules/server/containers/apps/favicon.nix

@@ -0,0 +1,301 @@
+{ config, containerCfg, pkgs, lib, builder, name, ... }:
+let
+  serverCfg = config.syscfg.server;
+  mediaCfg = config.syscfg.media;
+  port = 8080;
+  cacheControl = containerCfg.extra.cacheControl or "public, max-age=86400";
+  priority = toString (containerCfg.extra.priority or 1000);
+  logoSvgFileName = builtins.baseNameOf (toString mediaCfg.logo.svg);
+  logoSvgMount = "/assets/${logoSvgFileName}";
+  configFile = pkgs.writeText "favicon-config.json" (builtins.toJSON {
+    inherit cacheControl;
+    mappings = containerCfg.extra.mappings or {};
+    default = containerCfg.extra.default or null;
+    logoScale = containerCfg.extra.logoScale or 0.72;
+  });
+  pythonEnv = pkgs.python3.withPackages (ps: with ps; [
+    cairosvg
+    pillow
+  ]);
+  serverScript = pkgs.writeText "favicon-server.py" ''
+    import base64
+    import hashlib
+    from io import BytesIO
+    import json
+    import os
+    import re
+    from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
+    from pathlib import Path
+    from urllib.parse import urlsplit
+
+    import cairosvg
+    from PIL import Image
+
+
+    CONFIG_PATH = os.environ.get("FAVICON_CONFIG", "/config/config.json")
+    LOGO_PATH = os.environ.get("FAVICON_LOGO", "/assets/logo.svg")
+    CACHE_DIR = Path(os.environ.get("FAVICON_CACHE_DIR", "/cache"))
+    LISTEN_HOST = os.environ.get("FAVICON_LISTEN_HOST", "0.0.0.0")
+    LISTEN_PORT = int(os.environ.get("FAVICON_PORT", "8080"))
+    DEFAULT_CACHE_CONTROL = "public, max-age=86400"
+    PATH_PATTERN = re.compile(
+        r"(?i)(?:^|/)(?:"
+        r"favicon(?:-[0-9]+x[0-9]+)?\.(?:ico|png|svg)"
+        r"|apple-touch-icon(?:-precomposed)?\.png"
+        r"|android-chrome-(?:192x192|512x512)\.png"
+        r"|mstile-150x150\.png"
+        r")$"
+    )
+
+
+    with open(CONFIG_PATH, "r", encoding="utf-8") as fh:
+        APP_CONFIG = json.load(fh)
+    with open(LOGO_PATH, "rb") as fh:
+        LOGO_BYTES = fh.read()
+    LOGO_DATA_URI = "data:image/svg+xml;base64," + base64.b64encode(LOGO_BYTES).decode("ascii")
+
+
+    def _normalize_host(host):
+        return (host or "").split(":", 1)[0].strip().lower()
+
+
+    def _pick_profile(host):
+        mappings = APP_CONFIG.get("mappings", {})
+        exact = mappings.get(host)
+        if exact is not None:
+            return exact
+
+        wildcard_matches = []
+        for pattern, profile in mappings.items():
+            if pattern.startswith("*.") and host.endswith(pattern[1:].lower()):
+                wildcard_matches.append((pattern.count("."), profile))
+
+        if wildcard_matches:
+            wildcard_matches.sort(key=lambda item: item[0], reverse=True)
+            return wildcard_matches[0][1]
+
+        return APP_CONFIG.get("default")
+
+
+    def _color(value, fallback):
+        return value if isinstance(value, str) and value else fallback
+
+
+    def _badge_text(profile):
+        badge = profile.get("icon") or profile.get("label") or profile.get("text") or ""
+        badge = str(badge).strip()
+        if not badge:
+            return ""
+        return badge[:3].upper()
+
+
+    def _logo_scale():
+        scale = APP_CONFIG.get("logoScale", 0.72)
+        try:
+            scale = float(scale)
+        except (TypeError, ValueError):
+            return 0.72
+        return max(0.2, min(0.9, scale))
+
+
+    def _render_svg(profile):
+        bg = _color(profile.get("background"), "#111827")
+        fg = _color(profile.get("foreground"), "#f8fafc")
+        accent = _color(profile.get("accent"), "#38bdf8")
+        badge = _badge_text(profile)
+
+        canvas = 256
+        panel = 188
+        panel_offset = (canvas - panel) // 2
+        logo_size = int(canvas * _logo_scale())
+        logo_offset = (canvas - logo_size) // 2
+        badge_svg = ""
+        if badge:
+            badge_svg = f"""
+              <g>
+                <circle cx="196" cy="60" r="34" fill="{accent}" />
+                <text x="196" y="72"
+                  font-family="DejaVu Sans, sans-serif"
+                  font-size="34"
+                  font-weight="700"
+                  text-anchor="middle"
+                  fill="{fg}">{badge}</text>
+              </g>
+            """
+
+        return f"""<svg xmlns="http://www.w3.org/2000/svg" width="{canvas}" height="{canvas}" viewBox="0 0 {canvas} {canvas}">
+          <defs>
+            <radialGradient id="glow" cx="84%" cy="16%" r="75%">
+              <stop offset="0%" stop-color="{accent}" stop-opacity="0.34" />
+              <stop offset="100%" stop-color="{accent}" stop-opacity="0" />
+            </radialGradient>
+          </defs>
+          <rect width="{canvas}" height="{canvas}" rx="56" fill="{bg}" />
+          <rect width="{canvas}" height="{canvas}" rx="56" fill="url(#glow)" />
+          <rect x="{panel_offset}" y="{panel_offset}" width="{panel}" height="{panel}" rx="44" fill="#ffffff" fill-opacity="0.08" stroke="{accent}" stroke-opacity="0.6" stroke-width="6" />
+          <rect x="42" y="214" width="172" height="10" rx="5" fill="{accent}" fill-opacity="0.9" />
+          <image href="{LOGO_DATA_URI}" x="{logo_offset}" y="{logo_offset}" width="{logo_size}" height="{logo_size}" preserveAspectRatio="xMidYMid meet" />
+          {badge_svg}
+        </svg>"""
+
+
+    def _target_spec(path):
+        name = Path(path).name.lower()
+        if name.endswith(".svg"):
+            return ("svg", None)
+        if name.endswith(".ico"):
+            return ("ico", 64)
+
+        known_sizes = {
+            "apple-touch-icon.png": 180,
+            "apple-touch-icon-precomposed.png": 180,
+            "android-chrome-192x192.png": 192,
+            "android-chrome-512x512.png": 512,
+            "mstile-150x150.png": 150,
+            "favicon.png": 256,
+        }
+        if name in known_sizes:
+            return ("png", known_sizes[name])
+
+        match = re.search(r"([0-9]{2,4})x([0-9]{2,4})", name)
+        if match:
+            return ("png", int(match.group(1)))
+        return ("png", 256)
+
+
+    def _cache_key(host, spec, profile):
+        payload = json.dumps(
+            {"host": host, "spec": spec, "profile": profile, "logo": hashlib.sha256(LOGO_BYTES).hexdigest()},
+            sort_keys=True,
+        ).encode("utf-8")
+        return hashlib.sha256(payload).hexdigest()
+
+
+    def _mime(ext):
+        return {
+            "svg": "image/svg+xml",
+            "png": "image/png",
+            "ico": "image/x-icon",
+        }[ext]
+
+
+    def _generate_asset(host, profile, path):
+        spec = _target_spec(path)
+        cache_name = f"{_cache_key(host, spec, profile)}.{spec[0]}"
+        target = CACHE_DIR / cache_name
+        if target.exists():
+            return target, _mime(spec[0])
+
+        CACHE_DIR.mkdir(parents=True, exist_ok=True)
+        svg = _render_svg(profile).encode("utf-8")
+        if spec[0] == "svg":
+            target.write_bytes(svg)
+            return target, _mime("svg")
+
+        png_bytes = cairosvg.svg2png(bytestring=svg, output_width=spec[1], output_height=spec[1])
+        if spec[0] == "png":
+            target.write_bytes(png_bytes)
+            return target, _mime("png")
+
+        image = Image.open(BytesIO(png_bytes))
+        image.save(target, format="ICO", sizes=[(64, 64), (48, 48), (32, 32), (16, 16)])
+        image.close()
+        return target, _mime("ico")
+
+
+    class Handler(BaseHTTPRequestHandler):
+        server_version = "favicon-router/1.0"
+
+        def _serve(self, include_body):
+            path = urlsplit(self.path).path
+            if not PATH_PATTERN.search(path):
+                self.send_error(404)
+                return
+
+            host = _normalize_host(self.headers.get("Host", ""))
+            profile = _pick_profile(host)
+            if not profile:
+                self.send_error(404, "No favicon mapping for host")
+                return
+
+            asset_path, content_type = _generate_asset(host, profile, path)
+            payload = asset_path.read_bytes()
+            self.send_response(200)
+            self.send_header("Content-Type", content_type)
+            self.send_header("Content-Length", str(len(payload)))
+            self.send_header("Cache-Control", APP_CONFIG.get("cacheControl", DEFAULT_CACHE_CONTROL))
+            self.end_headers()
+            if include_body:
+                self.wfile.write(payload)
+
+        def do_GET(self):
+            self._serve(include_body=True)
+
+        def do_HEAD(self):
+            self._serve(include_body=False)
+
+        def log_message(self, fmt, *args):
+            print("%s - - [%s] %s" % (self.address_string(), self.log_date_time_string(), fmt % args))
+
+
+    if __name__ == "__main__":
+        httpd = ThreadingHTTPServer((LISTEN_HOST, LISTEN_PORT), Handler)
+        httpd.serve_forever()
+  '';
+  image = pkgs.dockerTools.streamLayeredImage {
+    name = "favicon";
+    tag = "1";
+    contents = [
+      pythonEnv
+      pkgs.fontconfig
+      pkgs.dejavu_fonts
+      pkgs.cacert
+      pkgs.tzdata
+    ];
+    config = {
+      Entrypoint = [ "${pythonEnv}/bin/python3" serverScript ];
+      ExposedPorts = { "${toString port}/tcp" = { }; };
+      WorkingDir = "/";
+    };
+  };
+in {
+  runtime = {
+    paths = [
+      {
+        path = "${serverCfg.path.config}/favicon";
+        mode = "0755";
+        dirs = [ "cache" ];
+      }
+    ];
+
+    containers = {
+      server = builder.mkContainer {
+        imageStream = image;
+        port = port;
+        extraEnv = {
+          FAVICON_CONFIG = "/config/config.json";
+          FAVICON_LOGO = logoSvgMount;
+          FAVICON_CACHE_DIR = "/cache";
+          FAVICON_PORT = toString port;
+          FONTCONFIG_FILE = "${pkgs.fontconfig.out}/etc/fonts/fonts.conf";
+          FONTCONFIG_PATH = "${pkgs.fontconfig.out}/etc/fonts";
+        };
+        extraLabels = {
+          "traefik.enable" = "true";
+          "traefik.http.routers.${name}.entrypoints" = "web-secure";
+          "traefik.http.routers.${name}.rule" = "HostRegexp(`{host:.+}`) && PathRegexp(`^/(?:.*\\/)?(?:favicon(?:-[0-9]+x[0-9]+)?\\.(?:ico|png|svg)|apple-touch-icon(?:-precomposed)?\\.png|android-chrome-(?:192x192|512x512)\\.png|mstile-150x150\\.png)$`)";
+          "traefik.http.routers.${name}.priority" = priority;
+          "traefik.http.routers.${name}.tls" = "true";
+          "traefik.http.services.${name}.loadbalancer.server.port" = toString port;
+        };
+        overrides = {
+          volumes = [
+            "${configFile}:/config/config.json:ro"
+            "${serverCfg.path.config}/favicon/cache:/cache"
+            "${mediaCfg.logo.svg}:${logoSvgMount}:ro"
+          ];
+        };
+      };
+    };
+  };
+}