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Fix regex to correctly capture default values in environment variable replacement #38

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Merged
merged 8 commits into from
Jun 10, 2025
Merged

Fix regex to correctly capture default values in environment variable replacement #38

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98d0465
Add tests
horihiro Jan 19, 2025
3d0af8b
Add `timeout` decorator
horihiro Jan 19, 2025
e1ed098
Add a package for tests
horihiro Jan 20, 2025
033caf8
Add test for right brace as default value
horihiro Jan 21, 2025
5fcbae6
Fix regex to correctly capture default values in environment variable…
horihiro Jan 21, 2025
701ba46
Add tests for unset environment variables without default value
horihiro Jan 24, 2025
d14db3b
Add tests for nested default values in environment variable interpola…
horihiro Jan 25, 2025
15fc66f
Fix regex to correctly capture default values without dollar signs in…
horihiro Jan 25, 2025
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3 changes: 2 additions & 1 deletion requirements.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -5,4 +5,5 @@ pyyaml>=6.0
twine>=3.8
build>=0.7
flake8==7.1.1
pylint==3.3.1
pylint==3.3.1
timeout-decorator==0.5.0
5 changes: 3 additions & 2 deletions src/pycomposefile/compose_element/compose_datatype_transformer.py
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Expand Up @@ -59,7 +59,7 @@ def update_value_with_resolved_environment(self, env_variable_name, env_variable
return re.sub(env_variable_name, env_variable_value, source_string)

def replace_environment_variables_with_empty_unset(self, value):
capture = re.compile(r"(\$+)\{(?P<variablename>\w+)\:-(?P<defaultvalue>.+)\}")
capture = re.compile(r"(\$+)\{(?P<variablename>\w+)\:-(?P<defaultvalue>[^$]*?)\}")
matches = capture.search(value)
if matches is not None and matches[1] == "$$":
return value
Expand All @@ -68,7 +68,8 @@ def replace_environment_variables_with_empty_unset(self, value):
default_value = matches.group("defaultvalue")
if env_var is None or len(env_var) == 0:
env_var = default_value
value = self.update_value_with_resolved_environment(f"\\{matches[0]}", env_var, value)
escaped = re.sub(r"([*+?{}])", r"\\\1", matches[0]) # escape special characters
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Copilot AI Jun 10, 2025

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Consider using re.escape(matches[0]) instead of a custom regex to escape special characters, as it improves readability and reduces the risk of missing additional special characters.

Suggested change
escaped = re.sub(r"([*+?{}])", r"\\\1", matches[0]) # escape special characters
escaped = re.escape(matches[0]) # escape special characters

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value = self.update_value_with_resolved_environment(f"\\{escaped}", env_var, value)
matches = capture.search(value)
return value

Expand Down
115 changes: 114 additions & 1 deletion src/tests/environment_variable_evaluation/test_environment_variables_braces.py
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Expand Up @@ -2,7 +2,7 @@
import os
from ..compose_generator import ComposeGenerator
from pycomposefile.compose_element import EmptyOrUnsetException

import timeout_decorator

class TestBracesNoUnderscoreNoDigitVariableInterpolation(TestCase):

Expand All @@ -19,6 +19,21 @@ def test_uppercase_with_default_when_unset_in_string_value(self):
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/bob")

def test_uppercase_without_default_when_unset_in_string_value(self):
env_var = "DEFAULTUNSET"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/")

@timeout_decorator.timeout(5)
def test_uppercase_with_nested_default_when_unset_in_string_value(self):
env_var = "DEFAULTUNSET"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-${CHILDUNSET:-bob}}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/bob")

@mock.patch.dict(os.environ, {"TESTCPUCOUNT": "1.5"})
def test_uppercase_in_decimal_value(self):
braced_env_var = "{TESTCPUCOUNT}"
Expand Down Expand Up @@ -48,6 +63,21 @@ def test_lowercase_with_default_when_unset_in_string_value(self):
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/bob")

def test_lowercase_without_default_when_unset_in_string_value(self):
env_var = "defaultunset"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/")

@timeout_decorator.timeout(5)
def test_lowercase_with_nested_default_when_unset_in_string_value(self):
env_var = "defaultunset"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-${childunset:-bob}}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/bob")

@mock.patch.dict(os.environ, {"testcpucount": "1.5"})
def test_lowercase_in_decimal_value(self):
braced_env_var = "{testcpucount}"
Expand Down Expand Up @@ -88,3 +118,86 @@ def test_service_with_double_dollar_sign_env_vars(self):
compose_file = ComposeGenerator.get_compose_with_double_dollar_sign_env_vars()

self.assertEqual(compose_file.services["frontend"].environment["ENVIRONMENT"], "$ENVIRONMENT")

@timeout_decorator.timeout(5)
def test_uppercase_with_asterisk_as_default(self):
env_var = "DEFAULTUNSET"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-*}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/*")

@timeout_decorator.timeout(5)
def test_uppercase_with_plus_as_default(self):
env_var = "DEFAULTUNSET"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-+}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/+")

@timeout_decorator.timeout(5)
def test_uppercase_with_question_as_default(self):
env_var = "DEFAULTUNSET"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-?}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/?")

@timeout_decorator.timeout(5)
def test_uppercase_with_rightbrace_as_default(self):
env_var = "DEFAULTUNSET"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-a}-}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/a-}") #

@timeout_decorator.timeout(5)
def test_lowercase_with_asterisk_as_default(self):
env_var = "defaultunset"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-*}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/*")

@timeout_decorator.timeout(5)
def test_lowercase_with_plus_as_default(self):
env_var = "defaultunset"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-+}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/+")

@timeout_decorator.timeout(5)
def test_lowercase_with_question_as_default(self):
env_var = "defaultunset"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-?}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/?")

@timeout_decorator.timeout(5)
def test_lowercase_with_rightbrace_as_default(self):
env_var = "defaultunset"
os.unsetenv(env_var)
braced_env_with_default_unset = "{" + env_var + ":-}}"
compose_file = ComposeGenerator.get_compose_with_string_value(braced_env_with_default_unset)
self.assertEqual(compose_file.services["frontend"].image, "awesome/}")

@timeout_decorator.timeout(5)
def test_uppercase_two_variables_with_default_in_string_value(self):
braced_first_env_var = "{HOSTPORT:-8080}"
braced_second_env_var = "{CONTAINERPORT:-80}"
compose_file = ComposeGenerator.get_with_two_environment_variables_in_string_value(braced_first_env_var, braced_second_env_var)
self.assertEqual(f"{compose_file.services['frontend'].ports[0]}", "8080:80/tcp")
self.assertEqual(compose_file.services['frontend'].ports[0].published, "8080")
self.assertEqual(compose_file.services['frontend'].ports[0].target, "80")

@timeout_decorator.timeout(5)
def test_lowercase_two_variables_with_default_in_string_value(self):
braced_first_env_var = "{httpport:-8080}"
braced_second_env_var = "{containerport:-80}"
compose_file = ComposeGenerator.get_with_two_environment_variables_in_string_value(braced_first_env_var, braced_second_env_var)
self.assertEqual(f"{compose_file.services['frontend'].ports[0]}", "8080:80/tcp")
self.assertEqual(compose_file.services['frontend'].ports[0].published, "8080")
self.assertEqual(compose_file.services['frontend'].ports[0].target, "80")