refactor(tente): vendor cgit nixos module

2 files changed, 290 insertions, 0 deletions

diff --git a/nixos/hosts/tente/cgit.nix b/nixos/hosts/tente/cgit.nix
new file mode 100644
index 0000000..70ea678
--- /dev/null
+++ b/nixos/hosts/tente/cgit.nix
@@ -0,0 +1,287 @@
+# copied from nixpkgs
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  cfgs = config.services.cgit;
+
+  settingType =
+    with lib.types;
+    oneOf [
+      bool
+      int
+      str
+    ];
+  repeatedSettingType =
+    with lib.types;
+    oneOf [
+      settingType
+      (listOf settingType)
+    ];
+
+  genAttrs' = names: f: lib.listToAttrs (map f names);
+
+  regexEscape =
+    let
+      # taken from https://github.com/python/cpython/blob/05cb728d68a278d11466f9a6c8258d914135c96c/Lib/re.py#L251-L266
+      special = [
+        "("
+        ")"
+        "["
+        "]"
+        "{"
+        "}"
+        "?"
+        "*"
+        "+"
+        "-"
+        "|"
+        "^"
+        "$"
+        "\\"
+        "."
+        "&"
+        "~"
+        "#"
+        " "
+        "\t"
+        "\n"
+        "\r"
+        "" # \v / 0x0B
+        "" # \f / 0x0C
+      ];
+    in
+    lib.replaceStrings special (map (c: "\\${c}") special);
+
+  stripLocation = cfg: lib.removeSuffix "/" cfg.nginx.location;
+
+  regexLocation = cfg: regexEscape (stripLocation cfg);
+
+  mkFastcgiPass = name: cfg: ''
+    ${
+      if cfg.nginx.location == "/" then
+        ''
+          fastcgi_param PATH_INFO $uri;
+        ''
+      else
+        ''
+          fastcgi_split_path_info ^(${regexLocation cfg})(/.+)$;
+          fastcgi_param PATH_INFO $fastcgi_path_info;
+        ''
+    }fastcgi_pass unix:${config.services.fcgiwrap.instances."cgit-${name}".socket.address};
+  '';
+
+  cgitrcLine =
+    name: value:
+    "${name}=${
+      if value == true then
+        "1"
+      else if value == false then
+        "0"
+      else
+        toString value
+    }";
+
+  # list value as multiple lines (for "readme" for example)
+  cgitrcEntry =
+    name: value: if lib.isList value then map (cgitrcLine name) value else [ (cgitrcLine name value) ];
+
+  mkCgitrc =
+    cfg:
+    pkgs.writeText "cgitrc" ''
+      # global settings
+      ${lib.concatStringsSep "\n" (
+        lib.flatten (
+          lib.mapAttrsToList cgitrcEntry ({ virtual-root = cfg.nginx.location; } // cfg.settings)
+        )
+      )}
+      ${lib.optionalString (cfg.scanPath != null) (cgitrcLine "scan-path" cfg.scanPath)}
+
+      # repository settings
+      ${lib.concatStrings (
+        lib.mapAttrsToList (url: settings: ''
+          ${cgitrcLine "repo.url" url}
+          ${lib.concatStringsSep "\n" (lib.mapAttrsToList (name: cgitrcLine "repo.${name}") settings)}
+        '') cfg.repos
+      )}
+
+      # extra config
+      ${cfg.extraConfig}
+    '';
+
+  fcgiwrapUnitName = name: "fcgiwrap-cgit-${name}";
+  fcgiwrapRuntimeDir = name: "/run/${fcgiwrapUnitName name}";
+  gitProjectRoot =
+    name: cfg: if cfg.scanPath != null then cfg.scanPath else "${fcgiwrapRuntimeDir name}/repos";
+
+in
+{
+  options = {
+    services.cgit = lib.mkOption {
+      description = "Configure cgit instances.";
+      default = { };
+      type = lib.types.attrsOf (
+        lib.types.submodule (
+          { config, ... }:
+          {
+            options = {
+              enable = lib.mkEnableOption "cgit";
+
+              package = lib.mkPackageOption pkgs "cgit" { };
+
+              nginx.virtualHost = lib.mkOption {
+                description = "VirtualHost to serve cgit on, defaults to the attribute name.";
+                type = lib.types.str;
+                default = config._module.args.name;
+                example = "git.example.com";
+              };
+
+              nginx.location = lib.mkOption {
+                description = "Location to serve cgit under.";
+                type = lib.types.str;
+                default = "/";
+                example = "/git/";
+              };
+
+              repos = lib.mkOption {
+                description = "cgit repository settings, see {manpage}`cgitrc(5)`";
+                type = with lib.types; attrsOf (attrsOf settingType);
+                default = { };
+                example = {
+                  blah = {
+                    path = "/var/lib/git/example";
+                    desc = "An example repository";
+                  };
+                };
+              };
+
+              scanPath = lib.mkOption {
+                description = "A path which will be scanned for repositories.";
+                type = lib.types.nullOr lib.types.path;
+                default = null;
+                example = "/var/lib/git";
+              };
+
+              settings = lib.mkOption {
+                description = "cgit configuration, see {manpage}`cgitrc(5)`";
+                type = lib.types.attrsOf repeatedSettingType;
+                default = { };
+                example = lib.literalExpression ''
+                  {
+                    enable-follow-links = true;
+                    source-filter = "''${pkgs.cgit}/lib/cgit/filters/syntax-highlighting.py";
+                  }
+                '';
+              };
+
+              extraConfig = lib.mkOption {
+                description = "These lines go to the end of cgitrc verbatim.";
+                type = lib.types.lines;
+                default = "";
+              };
+
+              user = lib.mkOption {
+                description = "User to run the cgit service as.";
+                type = lib.types.str;
+                default = "cgit";
+              };
+
+              group = lib.mkOption {
+                description = "Group to run the cgit service as.";
+                type = lib.types.str;
+                default = "cgit";
+              };
+            };
+          }
+        )
+      );
+    };
+  };
+
+  config = lib.mkIf (lib.any (cfg: cfg.enable) (lib.attrValues cfgs)) {
+    assertions = lib.mapAttrsToList (vhost: cfg: {
+      assertion = !cfg.enable || (cfg.scanPath == null) != (cfg.repos == { });
+      message = "Exactly one of services.cgit.${vhost}.scanPath or services.cgit.${vhost}.repos must be set.";
+    }) cfgs;
+
+    users = lib.mkMerge (
+      lib.flip lib.mapAttrsToList cfgs (
+        _: cfg: {
+          users.${cfg.user} = {
+            isSystemUser = true;
+            inherit (cfg) group;
+          };
+          groups.${cfg.group} = { };
+        }
+      )
+    );
+
+    services.fcgiwrap.instances = lib.flip lib.mapAttrs' cfgs (
+      name: cfg:
+      lib.nameValuePair "cgit-${name}" {
+        process = { inherit (cfg) user group; };
+        socket = { inherit (config.services.nginx) user group; };
+      }
+    );
+
+    systemd.services = lib.flip lib.mapAttrs' cfgs (
+      name: cfg:
+      lib.nameValuePair (fcgiwrapUnitName name) (
+        lib.mkIf (cfg.repos != { }) {
+          serviceConfig.RuntimeDirectory = fcgiwrapUnitName name;
+          preStart = ''
+            GIT_PROJECT_ROOT=${lib.escapeShellArg (gitProjectRoot name cfg)}
+            mkdir -p "$GIT_PROJECT_ROOT"
+            cd "$GIT_PROJECT_ROOT"
+            ${lib.concatLines (
+              lib.flip lib.mapAttrsToList cfg.repos (
+                name: repo: ''
+                  ln -s ${lib.escapeShellArg repo.path} ${lib.escapeShellArg name}
+                ''
+              )
+            )}
+          '';
+        }
+      )
+    );
+
+    services.nginx.enable = true;
+
+    services.nginx.virtualHosts = lib.mkMerge (
+      lib.mapAttrsToList (name: cfg: {
+        ${cfg.nginx.virtualHost} = {
+          locations =
+            (genAttrs' [ "cgit.css" "cgit.png" "favicon.ico" "robots.txt" ] (
+              fileName:
+              lib.nameValuePair "= ${stripLocation cfg}/${fileName}" {
+                alias = lib.mkDefault "${cfg.package}/cgit/${fileName}";
+              }
+            ))
+            // {
+              "~ ${regexLocation cfg}/.+/(info/refs|git-upload-pack)" = {
+                fastcgiParams = rec {
+                  SCRIPT_FILENAME = "${pkgs.git}/libexec/git-core/git-http-backend";
+                  GIT_HTTP_EXPORT_ALL = "1";
+                  GIT_PROJECT_ROOT = gitProjectRoot name cfg;
+                  HOME = GIT_PROJECT_ROOT;
+                };
+                extraConfig = mkFastcgiPass name cfg;
+              };
+              "${stripLocation cfg}/" = {
+                fastcgiParams = {
+                  SCRIPT_FILENAME = "${cfg.package}/cgit/cgit.cgi";
+                  QUERY_STRING = "$args";
+                  HTTP_HOST = "$server_name";
+                  CGIT_CONFIG = mkCgitrc cfg;
+                };
+                extraConfig = mkFastcgiPass name cfg;
+              };
+            };
+        };
+      }) cfgs
+    );
+  };
+}
diff --git a/nixos/hosts/tente/git-web.nix b/nixos/hosts/tente/git-web.nix
index 122157a..1c7ccf7 100644
--- a/nixos/hosts/tente/git-web.nix
+++ b/nixos/hosts/tente/git-web.nix
@@ -20,6 +20,9 @@ in
     };
   };
 
+  disabledModules = ["services/networking/cgit.nix"];
+  imports = [./cgit.nix];
+
   config = {
     services.nginx.virtualHosts.${cfg.domain} = {
       enableACME = true;