1 files changed, 359 insertions, 0 deletions
diff --git a/configs/elm-packages-proxy.nix b/configs/elm-packages-proxy.nix
new file mode 100644
index 0000000..caea188
--- /dev/null
+++ b/configs/elm-packages-proxy.nix
@@ -0,0 +1,359 @@
+{ config, lib, pkgs, ... }: let
+
+  cfg.nameserver = "1.1.1.1";
+  cfg.packageDir = "/var/lib/elm-packages";
+  cfg.port = 7782;
+
+  # TODO secret files
+  cfg.htpasswd = "/var/lib/certs/package.elm-lang.org/htpasswd";
+  cfg.sslCertificate = "/var/lib/certs/package.elm-lang.org/fullchain.pem";
+  cfg.sslCertificateKey = "/var/lib/certs/package.elm-lang.org/key.pem";
+
+  semverRegex =
+    "(?<major>0|[1-9]\\d*)\\.(?<minor>0|[1-9]\\d*)\\.(?<patch>0|[1-9]\\d*)(?:-(?<prerelease>(?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\\.(?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\\+(?<buildmetadata>[0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?";
+
+in {
+  services.nginx.virtualHosts."package.elm-lang.org" = {
+    addSSL = true;
+
+    sslCertificate = cfg.sslCertificate;
+    sslCertificateKey = cfg.sslCertificateKey;
+
+    locations."/all-packages".extraConfig = ''
+      proxy_pass http://127.0.0.1:${toString config.krebs.htgen.elm-packages-proxy.port};
+      proxy_pass_header Server;
+    '';
+
+    locations."/all-packages/since/".extraConfig = ''
+      proxy_pass http://127.0.0.1:${toString config.krebs.htgen.elm-packages-proxy.port};
+      proxy_pass_header Server;
+    '';
+
+    locations."~ ^/packages/(?<author>[A-Za-z0-9-]+)/(?<pname>[A-Za-z0-9-]+)/(?<version>${semverRegex})\$".extraConfig = ''
+      auth_basic "Restricted Area";
+      auth_basic_user_file ${cfg.htpasswd};
+
+      proxy_set_header X-User $remote_user;
+      proxy_set_header X-Author $author;
+      proxy_set_header X-Package $pname;
+      proxy_set_header X-Version $version;
+      proxy_pass_header Server;
+
+      proxy_pass http://127.0.0.1:${toString config.krebs.htgen.elm-packages-proxy.port};
+    '';
+
+    locations."~ ^/packages/(?<author>[A-Za-z0-9-]+)/(?<pname>[A-Za-z0-9-]+)/(?<version>${semverRegex})/(?:zipball|elm.json|endpoint.json)\$".extraConfig = ''
+      set $zipball "${cfg.packageDir}/$author/$pname/$version/zipball";
+      proxy_set_header X-Author $author;
+      proxy_set_header X-Package $pname;
+      proxy_set_header X-Version $version;
+      proxy_set_header X-Zipball $zipball;
+      proxy_pass_header Server;
+      resolver ${cfg.nameserver};
+
+      if (-f $zipball) {
+        set $new_uri http://127.0.0.1:${toString config.krebs.htgen.elm-packages-proxy.port};
+      }
+      if (!-f $zipball) {
+        set $new_uri https://package.elm-lang.org$request_uri;
+      }
+
+      proxy_pass $new_uri;
+    '';
+
+    locations."/search.json".extraConfig = ''
+      proxy_pass http://127.0.0.1:${toString config.krebs.htgen.elm-packages-proxy.port};
+      proxy_pass_header Server;
+    '';
+  };
+
+  krebs.htgen.elm-packages-proxy = {
+    port = cfg.port;
+    script = /* sh */ ''. ${pkgs.writeDash "elm-packages-proxy.sh" ''
+      PATH=${lib.makeBinPath [
+        pkgs.attr
+        pkgs.coreutils
+        pkgs.curl
+        pkgs.findutils
+        pkgs.gnugrep
+        pkgs.jq
+        pkgs.p7zip
+      ]}
+      export PATH
+      file_response() {(
+        status_code=$1
+        status_reason=$2
+        file=$3
+        content_type=$4
+
+        content_length=$(wc -c "$file" | cut -d\  -f1)
+
+        printf "HTTP/1.1 $status_code $status_reason\r\n"
+        printf 'Connection: close\r\n'
+        printf 'Content-Length: %d\r\n' "$content_length"
+        printf 'Content-Type: %s\r\n' "$content_type"
+        printf 'Server: %s\r\n' "$Server"
+        printf '\r\n'
+        cat "$file"
+      )}
+      string_response() {(
+        status_code=$1
+        status_reason=$2
+        response_body=$3
+        content_type=$4
+
+        printf "HTTP/1.1 $status_code $status_reason\r\n"
+        printf 'Connection: close\r\n'
+        printf 'Content-Length: %d\r\n' "$(expr ''${#response_body} + 1)"
+        printf 'Content-Type: %s\r\n' "$content_type"
+        printf 'Server: %s\r\n' "$Server"
+        printf '\r\n'
+        printf '%s\n' "$response_body"
+      )}
+
+      case "$Method $Request_URI" in
+        'GET /packages/'*)
+
+          author=$req_x_author
+          pname=$req_x_package
+          version=$req_x_version
+
+          zipball=${cfg.packageDir}/$author/$pname/$version/zipball
+          elmjson=$HOME/cache/$author%2F$pname%2F$version%2Felm.json
+          endpointjson=$HOME/cache/$author%2F$pname%2F$version%2Fendpoint.json
+          mkdir -p "$HOME/cache"
+
+          case $(basename $Request_URI) in
+            zipball)
+              file_response 200 OK "$zipball" application/zip
+              exit
+            ;;
+            elm.json)
+              if ! test -f "$elmjson"; then
+                7z x -so "$zipball" \*/elm.json > "$elmjson"
+              fi
+              file_response 200 OK "$elmjson" 'application/json; charset=UTF-8'
+              exit
+            ;;
+            endpoint.json)
+              if ! test -f "$endpointjson"; then
+                hash=$(sha1sum "$zipball" | cut -d\  -f1)
+                url=https://package.elm-lang.org/packages/$author/$pname/$version/zipball
+                jq -n \
+                    --arg hash "$hash" \
+                    --arg url "$url" \
+                    '{ $hash, $url }' \
+                  > "$endpointjson"
+              fi
+              file_response 200 OK "$endpointjson" 'application/json; charset=UTF-8'
+              exit
+            ;;
+          esac
+        ;;
+        'POST /packages/'*)
+
+          author=$req_x_author
+          pname=$req_x_package
+          user=$req_x_user
+          version=$req_x_version
+
+          action=uploading
+          force=''${req_x_force-false}
+          zipball=${cfg.packageDir}/$author/$pname/$version/zipball
+          elmjson=$HOME/cache/$author%2F$pname%2F$version%2Felm.json
+          endpointjson=$HOME/cache/$author%2F$pname%2F$version%2Fendpoint.json
+
+          if test -e "$zipball"; then
+            if test "$force" = true; then
+              zipball_owner=$(attr -q -g X-User "$zipball" || :)
+              if test "$zipball_owner" = "$req_x_user"; then
+                action=replacing
+                rm -f "$elmjson"
+                rm -f "$endpointjson"
+              else
+                string_response 403 Forbidden \
+                    "package already exists: $author/$pname@$version" \
+                    text/plain
+                exit
+              fi
+            else
+              string_response 409 Conflict \
+                  "package already exists: $author/$pname@$version" \
+                  text/plain
+              exit
+            fi
+          fi
+
+          echo "user $user is $action package $author/$pname@$version" >&2
+          # TODO check package
+          mkdir -p "$(dirname "$zipball")"
+          head -c $req_content_length > "$zipball"
+
+          attr -q -s X-User -V "$user" "$zipball" || :
+
+          string_response 200 OK \
+              "package created: $author/$pname@$version" \
+              text/plain
+
+          exit
+        ;;
+        'DELETE /packages/'*)
+
+          author=$req_x_author
+          pname=$req_x_package
+          user=$req_x_user
+          version=$req_x_version
+
+          zipball=${cfg.packageDir}/$author/$pname/$version/zipball
+          elmjson=$HOME/cache/$author%2F$pname%2F$version%2Felm.json
+          endpointjson=$HOME/cache/$author%2F$pname%2F$version%2Fendpoint.json
+
+          if test -e "$zipball"; then
+            zipball_owner=$(attr -q -g X-User "$zipball" || :)
+            if test "$zipball_owner" = "$req_x_user"; then
+              echo "user $user is deleting package $author/$pname@$version" >&2
+              rm -f "$elmjson"
+              rm -f "$endpointjson"
+              rm "$zipball"
+              string_response 200 OK \
+                  "package deleted: $author/$pname@$version" \
+                  text/plain
+              exit
+            else
+              string_response 403 Forbidden \
+                  "package already exists: $author/$pname@$version" \
+                  text/plain
+              exit
+            fi
+          fi
+        ;;
+        'GET /all-packages'|'POST /all-packages')
+
+          response=$(mktemp -t htgen.$$.elm-packages-proxy.all-packages.XXXXXXXX)
+          trap "rm $response >&2" EXIT
+
+          {
+            # upstream packages
+            curl -fsS https://package.elm-lang.org"$Request_URI"
+
+            # private packages
+            (cd ${cfg.packageDir}; find -mindepth 3 -maxdepth 3) |
+            jq -Rs '
+              split("\n") |
+              map(
+                select(.!="") |
+                match("^\\./(?<author>[^/]+)/(?<pname>[^/]+)/(?<version>[^/]+)$").captures |
+                map({key:.name,value:.string}) |
+                from_entries
+              ) |
+              reduce .[] as $item ({};
+                ($item|"\(.author)/\(.pname)") as $name |
+                . + { "\($name)": ((.[$name] // []) + [$item.version]) }
+              )
+            '
+          } |
+          jq -cs add > $response
+
+          file_response 200 OK "$response" 'application/json; charset=UTF-8'
+          exit
+        ;;
+        'GET /all-packages/since/'*|'POST /all-packages/since/'*)
+
+          response=$(mktemp -t htgen.$$.elm-packages-proxy.all-packages.XXXXXXXX)
+          trap "rm $response >&2" EXIT
+
+          {
+            # upstream packages
+            curl -fsS https://package.elm-lang.org"$Request_URI"
+
+            # private packages
+            (cd ${cfg.packageDir}; find -mindepth 3 -maxdepth 3) |
+            jq -Rs '
+              split("\n") |
+              map(
+                select(.!="") |
+                sub("^\\./(?<author>[^/]+)/(?<pname>[^/]+)/(?<version>[^/]+)$";"\(.author)/\(.pname)@\(.version)")
+              ) |
+              sort_by(split("@") | [.[0]]+(.[1]|split(".")|map(tonumber))) |
+              reverse
+            '
+          } |
+          jq -cs add > $response
+
+          file_response 200 OK "$response" 'application/json; charset=UTF-8'
+          exit
+        ;;
+        'GET /search.json')
+
+          searchjson=$HOME/cache/search.json
+          mkdir -p "$HOME/cache"
+
+          # update cached search.json
+          (
+            last_modified=$(
+              if test -f "$searchjson"; then
+                date -Rr "$searchjson"
+              else
+                date -R -d @0
+              fi
+            )
+            tempsearchjson=$(mktemp "$searchjson.XXXXXXXX")
+            trap 'rm "$tempsearchjson" >&2' EXIT
+            curl -fsS --compressed https://package.elm-lang.org/search.json \
+                -H "If-Modified-Since: $last_modified" \
+                -o "$tempsearchjson"
+            if test -s "$tempsearchjson"; then
+              mv "$tempsearchjson" "$searchjson"
+              trap - EXIT
+            fi
+          )
+
+          response=$(mktemp -t htgen.$$.elm-packages-proxy.search.XXXXXXXX)
+          trap 'rm "$response" >&2' EXIT
+
+          {
+            printf '{"upstream":'; cat "$searchjson"
+            printf ',"private":'; (cd ${cfg.packageDir}; find -mindepth 3 -maxdepth 3) |
+              jq -Rs '
+                split("\n") |
+                map(
+                  select(.!="") |
+                  match("^\\./(?<author>[^/]+)/(?<pname>[^/]+)/(?<version>[^/]+)$").captures |
+                  map({key:.name,value:.string}) |
+                  from_entries
+                ) |
+                map({
+                  key: "\(.author)/\(.pname)",
+                  value: .version,
+                }) |
+                from_entries
+              '
+            printf '}'
+          } |
+          jq -c '
+            reduce .upstream[] as $upstreamItem ({ private, output: [] };
+              .private[$upstreamItem.name] as $privateItem |
+              if $privateItem then
+                .output += [$upstreamItem * { version: $privateItem.version }] |
+                .private |= del(.[$upstreamItem.name])
+              else
+                .output += [$upstreamItem]
+              end
+            ) |
+
+            .output + (.private | to_entries | sort_by(.key) | map({
+              name: .key,
+              version: .value,
+              summary: "dummy summary",
+              license: "dummy license",
+            }))
+          ' \
+          > $response
+
+          file_response 200 OK "$response" 'application/json; charset=UTF-8'
+          exit
+        ;;
+      esac
+    ''}'';
+  };
+}