1 files changed, 44 insertions, 0 deletions
diff --git a/paste/util/import_string.py b/paste/util/import_string.py
new file mode 100644
index 0000000..af32b24
--- /dev/null
+++ b/paste/util/import_string.py
@@ -0,0 +1,44 @@
+"""
+'imports' a string -- converts a string to a Python object, importing
+any necessary modules and evaluating the expression.  Everything
+before the : in an import expression is the module path; everything
+after is an expression to be evaluated in the namespace of that
+module.
+
+Alternately, if no : is present, then import the modules and get the
+attributes as necessary.  Arbitrary expressions are not allowed in
+that case.
+"""
+
+def eval_import(s):
+    if ':' not in s:
+        return simple_import(s)
+    module_name, expr = s.split(':', 1)
+    module = import_module(module_name)
+    obj = eval(expr, module.__dict__)
+    return obj
+
+def simple_import(s):
+    parts = s.split('.')
+    module = import_module(parts[0])
+    name = parts[0]
+    parts = parts[1:]
+    while parts:
+        name += '.' + parts[0]
+        try:
+            module = import_module(name)
+            parts = parts[1:]
+        except ImportError:
+            break
+    obj = module
+    while parts:
+        obj = getattr(module, parts[0])
+        parts = parts[1:]
+    return obj
+
+def import_module(s):
+    mod = __import__(s)
+    parts = s.split('.')
+    for part in parts[1:]:
+        mod = getattr(mod, part)
+    return mod