fixed env var parser

pyinfra/config.py

@@ -1,6 +1,7 @@
 """Implements a config object with dot-indexing syntax."""
 import os
 from itertools import chain
+from operator import truth
 
 from envyaml import EnvYAML
 from funcy import first, juxt, butlast, last
@@ -51,4 +52,4 @@ def parse_disjunction_string(disjunction_string):
 
     options = disjunction_string.split("|")
     identifiers, fallback_value = juxt(butlast, last)(options)
-    return first(chain(filter(try_parse_env_var, identifiers), [fallback_value]))
+    return first(chain(filter(truth, map(try_parse_env_var, identifiers)), [fallback_value]))

pyinfra/test/unit_tests/config_test.py

@@ -1,9 +1,10 @@
+import os
 import tempfile
 
 import pytest
 import yaml
 
-from pyinfra.config import Config
+from pyinfra.config import Config, parse_disjunction_string
 
 
 @pytest.fixture
@@ -36,3 +37,9 @@ def test_dot_access_key_does_not_exists(config):
 
 def test_access_key_does_not_exists(config):
     assert config["B"] is None
+
+
+def test_parse_disjunction_string():
+    assert parse_disjunction_string("A|Bb|c") == "c"
+    os.environ["Bb"] = "d"
+    assert parse_disjunction_string("A|Bb|c") == "d"

pyinfra/visitor.py

@@ -27,8 +27,10 @@ def get_object_descriptor(body):
 
 
 def get_response_object_descriptor(body):
-    return {"bucket_name": parse_disjunction_string(CONFIG.storage.bucket),
-            "object_name": get_response_object_name(body)}
+    return {
+        "bucket_name": parse_disjunction_string(CONFIG.storage.bucket),
+        "object_name": get_response_object_name(body),
+    }
 
 
 class ResponseStrategy(abc.ABC):