introduce build parameters

pygomx-module/setup.py

@@ -1,3 +1,4 @@
+import os
 import subprocess
 from contextlib import suppress
 from setuptools import Command, setup
@@ -12,12 +13,45 @@ class CustomCommand(Command):
         pass
 
     def run(self) -> None:
+        # configure the go build via env vars
+        # keep defaults in sync with build_ffi.py
+        go_tags_str = os.getenv("PYGOMX_GO_TAGS")
+        if go_tags_str and len(go_tags_str.strip()) > 0:
+            go_tags = go_tags_str.split(",")
+        else:
+            go_tags = []
+
+        match os.getenv("PYGOMX_BUILD_MODE", "static"):
+            case "static":
+                build_mode_name = "c-archive"
+                build_mode_ext = ".a"
+            case "shared":
+                build_mode_name = "c-shared"
+                build_mode_ext = ".so"
+            case _:
+                raise ValueError("Invalid PYGOMX_BUILD_MODE.")
+
+        match os.getenv("PYGOMX_OLM_FLAVOR", "colm"):
+            case "none":
+                go_tags += ["nocrypto"]
+            case "colm":
+                go_tags += ["colm"]
+            case "goolm":
+                go_tags += ["goolm"]
+            case "vodozemac":
+                go_tags += ["vodozemac"]
+                raise ValueError("Vodozemac not supported (yet).")
+            case _:
+                raise ValueError("Invalid PYGOMX_OLM_FLAVOR.")
+
         go_call = [
             "go",
             "build",
-            "-buildmode=c-archive",
+            f"-buildmode=${build_mode_name}",
+            "-tags",
+            ",".join(go_tags),
             "-o",
-            "../pygomx-module/libmxclient.a",
+            f"../pygomx-module/libmxclient${build_mode_ext}",
             ".",
         ]
         subprocess.call(go_call, cwd="../libmxclient")