discord: rework sources and update script

Signed-off-by: Sefa Eyeoglu <contact@scrumplex.net>

pkgs/applications/networking/instant-messengers/discord/darwin.nix

@@ -106,17 +106,7 @@ stdenv.mkDerivation {
   passthru = {
     # make it possible to run disableBreakingUpdates standalone
     inherit disableBreakingUpdates;
-    updateScript = writeScript "discord-update-script" ''
-      #!/usr/bin/env nix-shell
-      #!nix-shell -i bash -p curl gnugrep common-updater-scripts
-      set -x
-      set -eou pipefail;
-      url=$(curl -sI -o /dev/null -w '%header{location}' "https://discord.com/api/download/${branch}?platform=osx&format=dmg")
-      version=$(echo $url | grep -oP '/\K(\d+\.){2}\d+')
-      update-source-version ${
-        lib.optionalString (!stdenv.buildPlatform.isDarwin) "pkgsCross.aarch64-darwin."
-      }${pname} "$version" --file=./pkgs/applications/networking/instant-messengers/discord/default.nix --version-key=${branch}
-    '';
+    updateScript = ./update.py;
 
     tests = {
       withVencord = self.override {

pkgs/applications/networking/instant-messengers/discord/default.nix

@@ -12,52 +12,24 @@ let
   variants = rec {
     x86_64-linux = {
       discord = rec {
-        version = "0.0.115";
-
-        src = fetchurl {
-          url = "https://stable.dl2.discordapp.net/apps/linux/${version}/discord-${version}.tar.gz";
-          hash = "sha256-DXGlo9qdmJTqm6ResvspauQ0awIFSuYalcpVXEfTxK4=";
-        };
-
         branch = "stable";
         binaryName = desktopName;
         desktopName = "Discord";
         self = discord;
       };
-      discord-ptb = rec {
-        version = "0.0.167";
-
-        src = fetchurl {
-          url = "https://ptb.dl2.discordapp.net/apps/linux/${version}/discord-ptb-${version}.tar.gz";
-          hash = "sha256-Q4IrmvoP//49GN2L9kRQ/zG28XjicJEXZpVG6RklFB8=";
-        };
-
+      discord-ptb = {
         branch = "ptb";
         binaryName = "DiscordPTB";
         desktopName = "Discord PTB";
         self = discord-ptb;
       };
-      discord-canary = rec {
-        version = "0.0.811";
-
-        src = fetchurl {
-          url = "https://canary.dl2.discordapp.net/apps/linux/${version}/discord-canary-${version}.tar.gz";
-          hash = "sha256-kg0o5KyBohmnk/czUQLVsA1GV2P6DUQLy0KhMaj80Sk=";
-        };
-
+      discord-canary = {
         branch = "canary";
         binaryName = "DiscordCanary";
         desktopName = "Discord Canary";
         self = discord-canary;
       };
-      discord-development = rec {
-        version = "0.0.92";
-
-        src = fetchurl {
-          url = "https://development.dl2.discordapp.net/apps/linux/${version}/discord-development-${version}.tar.gz";
-          hash = "sha256-oG50YrXQUCnbn+rO0EeRjixeqvXYBdnyqdomdPfxfos=";
-        };
-
+      discord-development = {
         branch = "development";
         binaryName = "DiscordDevelopment";
         desktopName = "Discord Development";
@@ -66,52 +38,24 @@ let
     };
     x86_64-darwin = {
       discord = rec {
-        version = "0.0.362";
-
-        src = fetchurl {
-          url = "https://stable.dl2.discordapp.net/apps/osx/${version}/Discord.dmg";
-          hash = "sha256-DHe0WwJOB3mm1HbQwEOJ9NWqxzhOBQynhjJXYSNvA/k=";
-        };
-
         branch = "stable";
         binaryName = desktopName;
         desktopName = "Discord";
         self = discord;
       };
       discord-ptb = rec {
-        version = "0.0.192";
-
-        src = fetchurl {
-          url = "https://ptb.dl2.discordapp.net/apps/osx/${version}/DiscordPTB.dmg";
-          hash = "sha256-AZ9enKJf6WZLELFLKrzeyAR/Q/pzD8SGvCPcInS8vsk=";
-        };
-
         branch = "ptb";
         binaryName = desktopName;
         desktopName = "Discord PTB";
         self = discord-ptb;
       };
       discord-canary = rec {
-        version = "0.0.867";
-
-        src = fetchurl {
-          url = "https://canary.dl2.discordapp.net/apps/osx/${version}/DiscordCanary.dmg";
-          hash = "sha256-67B2wZRZEOKutMPsrRlc96UZWShYLAgwOoF2/QzBgzE=";
-        };
-
         branch = "canary";
         binaryName = desktopName;
         desktopName = "Discord Canary";
         self = discord-canary;
       };
       discord-development = rec {
-        version = "0.0.100";
-
-        src = fetchurl {
-          url = "https://development.dl2.discordapp.net/apps/osx/${version}/DiscordDevelopment.dmg";
-          hash = "sha256-PknNHr9txxp3+nO7FgHH7n04qx6p6Jzbs92/Hcfh13Y=";
-        };
-
         branch = "development";
         binaryName = desktopName;
         desktopName = "Discord Development";
@@ -144,16 +88,25 @@ let
     sourceProvenance = with lib.sourceTypes; [ binaryNativeCode ];
   };
   package = if stdenv.hostPlatform.isLinux then ./linux.nix else ./darwin.nix;
+
+  sources = lib.importJSON ./sources.json;
 in
 lib.genAttrs [ "discord" "discord-ptb" "discord-canary" "discord-development" ] (
   pname:
   let
     args = (variants.${stdenv.hostPlatform.system} or variants.default).${pname};
+    platformName = if stdenv.hostPlatform.isDarwin then "osx" else "linux";
+    source = sources."${platformName}-${args.branch}";
   in
   callPackage package (
     args
     // {
       inherit pname;
+      inherit (source) version;
+
+      src = fetchurl {
+        inherit (source) url hash;
+      };
 
       meta = meta // {
         mainProgram = args.binaryName;

pkgs/applications/networking/instant-messengers/discord/linux.nix

@@ -253,14 +253,7 @@ stdenv.mkDerivation (finalAttrs: {
   passthru = {
     # make it possible to run disableBreakingUpdates standalone
     inherit disableBreakingUpdates;
-    updateScript = writeScript "discord-update-script" ''
-      #!/usr/bin/env nix-shell
-      #!nix-shell -i bash -p curl gnugrep common-updater-scripts
-      set -eou pipefail;
-      url=$(curl -sI -o /dev/null -w '%header{location}' "https://discord.com/api/download/${branch}?platform=linux&format=tar.gz")
-      version=$(echo $url | grep -oP '/\K(\d+\.){2}\d+')
-      update-source-version ${pname} "$version" --file=./pkgs/applications/networking/instant-messengers/discord/default.nix --version-key=${branch}
-    '';
+    updateScript = ./update.py;
 
     tests = {
       withVencord = self.override {

pkgs/applications/networking/instant-messengers/discord/sources.json

@@ -0,0 +1,42 @@
+{
+  "linux-canary": {
+    "hash": "sha256-kg0o5KyBohmnk/czUQLVsA1GV2P6DUQLy0KhMaj80Sk=",
+    "url": "https://canary.dl2.discordapp.net/apps/linux/0.0.811/discord-canary-0.0.811.tar.gz",
+    "version": "0.0.811"
+  },
+  "linux-development": {
+    "hash": "sha256-oG50YrXQUCnbn+rO0EeRjixeqvXYBdnyqdomdPfxfos=",
+    "url": "https://development.dl2.discordapp.net/apps/linux/0.0.92/discord-development-0.0.92.tar.gz",
+    "version": "0.0.92"
+  },
+  "linux-ptb": {
+    "hash": "sha256-Q4IrmvoP//49GN2L9kRQ/zG28XjicJEXZpVG6RklFB8=",
+    "url": "https://ptb.dl2.discordapp.net/apps/linux/0.0.167/discord-ptb-0.0.167.tar.gz",
+    "version": "0.0.167"
+  },
+  "linux-stable": {
+    "hash": "sha256-DXGlo9qdmJTqm6ResvspauQ0awIFSuYalcpVXEfTxK4=",
+    "url": "https://stable.dl2.discordapp.net/apps/linux/0.0.115/discord-0.0.115.tar.gz",
+    "version": "0.0.115"
+  },
+  "osx-canary": {
+    "hash": "sha256-67B2wZRZEOKutMPsrRlc96UZWShYLAgwOoF2/QzBgzE=",
+    "url": "https://canary.dl2.discordapp.net/apps/osx/0.0.867/DiscordCanary.dmg",
+    "version": "0.0.867"
+  },
+  "osx-development": {
+    "hash": "sha256-PknNHr9txxp3+nO7FgHH7n04qx6p6Jzbs92/Hcfh13Y=",
+    "url": "https://development.dl2.discordapp.net/apps/osx/0.0.100/DiscordDevelopment.dmg",
+    "version": "0.0.100"
+  },
+  "osx-ptb": {
+    "hash": "sha256-AZ9enKJf6WZLELFLKrzeyAR/Q/pzD8SGvCPcInS8vsk=",
+    "url": "https://ptb.dl2.discordapp.net/apps/osx/0.0.192/DiscordPTB.dmg",
+    "version": "0.0.192"
+  },
+  "osx-stable": {
+    "hash": "sha256-DHe0WwJOB3mm1HbQwEOJ9NWqxzhOBQynhjJXYSNvA/k=",
+    "url": "https://stable.dl2.discordapp.net/apps/osx/0.0.362/Discord.dmg",
+    "version": "0.0.362"
+  }
+}

pkgs/applications/networking/instant-messengers/discord/update.py

@@ -0,0 +1,110 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i python3 -p python3
+
+from enum import StrEnum
+from typing import List, Tuple
+from subprocess import PIPE, Popen
+import json
+import urllib.request
+import re
+import os.path
+
+SRC_NAME = "source"
+
+VERSION_REGEX = re.compile(r"\/([\d.]+)\/")
+
+
+class Platform(StrEnum):
+    LINUX = "linux"
+    MACOS = "osx"
+
+    def format_type(self):
+        if self.value == Platform.LINUX.value:
+            return "tar.gz"
+        elif self.value == Platform.MACOS.value:
+            return "dmg"
+        raise RuntimeError("Invalid platform")
+
+
+class Branch(StrEnum):
+    STABLE = "stable"
+    PTB = "ptb"
+    CANARY = "canary"
+    DEVELOPMENT = "development"
+
+
+Variant = Tuple[Platform, Branch]
+
+
+def serialize_variant(variant: Variant) -> str:
+    platform, branch = variant
+    return f"{platform}-{branch}"
+
+
+def url_for_variant(variant: Variant) -> str:
+    platform, branch = variant
+
+    return f"https://discord.com/api/download/{branch.value}?platform={platform.value}&format={platform.format_type()}"
+
+
+def fetch_redirect_url(url: str) -> str:
+    headers = {"user-agent": "Nixpkgs-Discord-Update-Script/0.0.0"}
+    # note that urllib follows redirects by default. So we can extract the final url from the response object
+    req = urllib.request.Request(url, headers=headers)
+    with urllib.request.urlopen(req) as response:
+        return response.url
+
+
+def version_from_url(url: str) -> str:
+    matches = VERSION_REGEX.search(url)
+    assert matches, f"Url {url} must contain version number"
+    version = matches.group(1)
+    assert version
+    return version
+
+
+def prefetch(url: str) -> str:
+    with Popen(["nix-prefetch-url", "--name", "source", url], stdout=PIPE) as p:
+        assert p.stdout
+        b32_hash = p.stdout.read().decode("utf-8").strip()
+    with Popen(
+        ["nix-hash", "--to-sri", "--type", "sha256", b32_hash], stdout=PIPE
+    ) as p:
+        assert p.stdout
+        sri_hash = p.stdout.read().decode("utf-8").strip()
+    return sri_hash
+
+
+def main():
+    variants: List[Variant] = [
+        (Platform.LINUX, Branch.STABLE),
+        (Platform.LINUX, Branch.PTB),
+        (Platform.LINUX, Branch.CANARY),
+        (Platform.LINUX, Branch.DEVELOPMENT),
+        (Platform.MACOS, Branch.STABLE),
+        (Platform.MACOS, Branch.PTB),
+        (Platform.MACOS, Branch.CANARY),
+        (Platform.MACOS, Branch.DEVELOPMENT),
+    ]
+
+    sources = {}
+
+    for v in variants:
+        url = url_for_variant(v)
+        url = fetch_redirect_url(url)
+        version = version_from_url(url)
+        sri_hash = prefetch(url)
+
+        sources[serialize_variant(v)] = {
+            "url": url,
+            "version": version,
+            "hash": sri_hash,
+        }
+
+    with open(os.path.join(os.path.dirname(__file__), "sources.json"), "w") as f:
+        json.dump(sources, f, indent=2, sort_keys=True)
+        f.write("\n")
+
+
+if __name__ == "__main__":
+    main()