add drv generator to extractor

lib/extractor/default.nix

@@ -8,9 +8,9 @@
     python37
     python38
   ]),
-  limitPythonVersions ? [],
   ...
 }:
+with builtins;
 with lib;
 let
   commit = "1434cc0ee2da462f0c719d3a4c0ab4c87d0931e7";
@@ -97,7 +97,7 @@ let
     f.close();
     exec(compile(code, __file__, 'exec'))
   '';
-  script = ''
+  script = pyVersions: ''
     mkdir $out
     ${concatStringsSep "\n" (forEach pythonInterpreters (interpreter:
       let
@@ -107,7 +107,7 @@ let
         minor = elemAt verSplit 1;
         v = "${major}${minor}";
       # only use selected interpreters
-      in optionalString (limitPythonVerions == [] || elem v limitPythonVerions) ''
+      in optionalString (pyVersions == [] || elem v pyVersions) ''
         echo "extracting metadata for python${v}"
         out_file=$out/python${v}.json ${py}/bin/python -c "${setuptools_shim}" install &> $out/python${v}.log || true
       ''
@@ -118,14 +118,14 @@ let
     echo "extracting dependencies"
     out_file=$out/python.json ${py}/bin/python -c "${setuptools_shim}" install &> $out/python.log || true
   '';
-  base_derivation = with pkgs; {
+  base_derivation = pyVersions: with pkgs; {
     buildInputs = [ unzip pkg-config pipenv ];
     phases = ["unpackPhase" "installPhase"];
     # Tells our modified python builtins to dump setup attributes instead of doing an actual installation
     dump_setup_attrs = "y";
     PYTHONIOENCODING = "utf8";  # My gut feeling is that encoding issues might decrease by this
     LANG = "C.utf8";
-    installPhase = script;
+    installPhase = script pyVersions;
   };
 in
 with pkgs;
@@ -133,21 +133,33 @@ rec {
   inherit machnix_source pythonInterpreters;
   example = extractor {pkg = "requests"; version = "2.22.0";};
   extract_from_src = {py, src}:
-    stdenv.mkDerivation ( base_derivation // {
+    stdenv.mkDerivation ( (base_derivation []) // {
       inherit src;
       name = "package-requirements";
       installPhase = script_single (mkPy py);
     });
-  extractor = {pkg, version}:
+  extractor = {pkg, version, ...}:
     stdenv.mkDerivation ({
       name = "${pkg}-${version}-requirements";
       src = fetchPypi pkg version;
-    } // base_derivation);
-  extractor-fast = {pkg, version, url, sha256}:
-    stdenv.mkDerivation ({
+    } // (base_derivation []));
+  extractor-fast = {pkg, version, url, sha256, pyVersions ? [], ...}:
+    stdenv.mkDerivation ( rec {
       name = "${pkg}-${version}-requirements";
-      src = pkgs.fetchurl {
+      src = (pkgs.fetchurl {
         inherit url sha256;
-      };
-    } // base_derivation);
+      }).overrideAttrs (_: {
+        name = replaceStrings [" "] [""] _.name;
+      });
+    } // (base_derivation pyVersions));
+  make-drvs =
+    let
+      jobs = fromJSON (readFile (getEnv "EXTRACTOR_JOBS_JSON_FILE"));
+      results = listToAttrs (map (job:
+        nameValuePair
+          "${job.pkg}#${job.version}"
+          (extractor-fast job).drvPath
+      ) jobs);
+    in toJSON results;
+
 }

lib/extractor/make-drvs.nix

@@ -0,0 +1 @@
+(import ./default.nix {}).make-drvs