Add .venv to 8r-1c-srv6-pm

Author: cscarpitta

nets/8r-1c-srv6-pm/.venv

@@ -0,0 +1 @@
+/root/.mininet-venv

nets/8r-1c-srv6-pm/isis8d.py

@@ -1,6 +1,26 @@
 #!/usr/bin/python
 
-import os
+# Activate virtual environment if a venv path has been specified in .venv
+# This must be executed only if this file has been executed as a 
+# script (instead of a module)
+if __name__ == '__main__':
+    # Check if .venv file exists
+    if os.path.exists('.venv'):
+        with open('.venv', 'r') as venv_file:
+            # Get virtualenv path from .venv file
+            venv_path = venv_file.read()
+        # Get path of the activation script
+        venv_path = os.path.join(venv_path, 'bin/activate_this.py')
+        if not os.path.exists(venv_path):
+            print('Virtual environment path specified in .venv '
+                  'points to an invalid path\n')
+            exit(-2)
+        with open(venv_path) as f:
+            # Read the activation script
+            code = compile(f.read(), venv_path, 'exec')
+            # Execute the activation script to activate the venv
+            exec(code, {'__file__': venv_path})
+
 import shutil
 from mininet.topo import Topo
 from mininet.node import Host, OVSBridge