paraview venv helper

Author: jourdain

05_paraview/SimpleCone.py

@@ -1,10 +1,4 @@
-# Try handle virtual env if provided
-import sys
-
-if "--virtual-env" in sys.argv:
-    virtualEnvPath = sys.argv[sys.argv.index("--virtual-env") + 1]
-    virtualEnv = virtualEnvPath + "/bin/activate_this.py"
-    exec(open(virtualEnv).read(), {"__file__": virtualEnv})
+import venv
 
 from trame import update_state, change
 from trame.html import vuetify, paraview

05_paraview/StateLoader.py

@@ -1,11 +1,5 @@
-# Try handle virtual env if provided
+import venv
 import os
-import sys
-
-if "--virtual-env" in sys.argv:
-    virtualEnvPath = sys.argv[sys.argv.index("--virtual-env") + 1]
-    virtualEnv = virtualEnvPath + "/bin/activate_this.py"
-    exec(open(virtualEnv).read(), {"__file__": virtualEnv})
 
 import trame
 from trame.html import vuetify, paraview

05_paraview/venv.py

@@ -0,0 +1,18 @@
+import os
+import site
+import sys
+
+if "--venv" in sys.argv:
+    # Code taken from virutal-env::bin/active_this.py
+    venv_path = sys.argv[sys.argv.index("--venv") + 1]
+    bin_dir = os.path.abspath(os.path.join(venv_path, "bin"))
+    base = bin_dir[: -len("bin") - 1]
+    os.environ["PATH"] = os.pathsep.join([bin_dir] + os.environ.get("PATH", "").split(os.pathsep))
+    os.environ["VIRTUAL_ENV"] = base
+    prev_length = len(sys.path)
+    python_libs = os.path.join(base, f"lib/python{sys.version_info.major}.{sys.version_info.minor}/site-packages")
+    path = os.path.realpath(os.path.join(bin_dir, python_libs))
+    site.addsitedir(python_libs.decode("utf-8") if "" else python_libs)
+    sys.path[:] = sys.path[prev_length:] + sys.path[0:prev_length]
+    sys.real_prefix = sys.prefix
+    sys.prefix = base