Fix IndexError in apache_beam.utils.processes when pip subprocess fails with short command

CHANGES.md

@@ -83,6 +83,7 @@
 
 ## Bugfixes
 
+* Fixed IndexError in `apache_beam.utils.processes` when pip subprocess fails with short command (e.g. `pip install pkg`) (Python) ([#37515](https://github.com/apache/beam/issues/37515)).
 * Fixed X (Java/Python) ([#X](https://github.com/apache/beam/issues/X)).
 
 ## Security Fixes

sdks/python/apache_beam/utils/processes.py

@@ -52,15 +52,12 @@ def call(*args, **kwargs):
     except OSError as e:
       raise RuntimeError("Executable {} not found".format(args[0])) from e
     except subprocess.CalledProcessError as error:
-      if isinstance(args, tuple) and (args[0][2] == "pip"):
-        raise RuntimeError( \
-          "Full traceback: {}\n Pip install failed for package: {} \
-          \n Output from execution of subprocess: {}" \
-          .format(traceback.format_exc(), args[0][6], error. output)) from error
-      else:
-        raise RuntimeError("Full trace: {}\
-           \n Output of the failed child process: {} " \
-          .format(traceback.format_exc(), error.output)) from error
+      raise RuntimeError(
+          "Output from execution of subprocess: {}\n"
+          "Command that failed: {}\nFull trace: {}".format(
+              error.output if error.output is not None else "(not captured)",
+              args,
+              traceback.format_exc())) from error
     return out
 
   def check_call(*args, **kwargs):
@@ -71,15 +68,12 @@ def check_call(*args, **kwargs):
     except OSError as e:
       raise RuntimeError("Executable {} not found".format(args[0])) from e
     except subprocess.CalledProcessError as error:
-      if isinstance(args, tuple) and (args[0][2] == "pip"):
-        raise RuntimeError( \
-          "Full traceback: {} \n Pip install failed for package: {} \
-          \n Output from execution of subprocess: {}" \
-          .format(traceback.format_exc(), args[0][6], error.output)) from error
-      else:
-        raise RuntimeError("Full trace: {} \
-          \n Output of the failed child process: {}" \
-          .format(traceback.format_exc(), error.output)) from error
+      raise RuntimeError(
+          "Output from execution of subprocess: {}\n"
+          "Command that failed: {}\nFull trace: {}".format(
+              error.output if error.output is not None else "(not captured)",
+              args,
+              traceback.format_exc())) from error
     return out
 
   def check_output(*args, **kwargs):
@@ -90,15 +84,12 @@ def check_output(*args, **kwargs):
     except OSError as e:
       raise RuntimeError("Executable {} not found".format(args[0])) from e
     except subprocess.CalledProcessError as error:
-      if isinstance(args, tuple) and (args[0][2] == "pip"):
-        raise RuntimeError( \
-          "Full traceback: {} \n Pip install failed for package: {} \
-          \n Output from execution of subprocess: {}" \
-          .format(traceback.format_exc(), args[0][6], error.output)) from error
-      else:
-        raise RuntimeError("Full trace: {}, \
-           output of the failed child process {} "\
-          .format(traceback.format_exc(), error.output)) from error
+      raise RuntimeError(
+          "Output from execution of subprocess: {}\n"
+          "Command that failed: {}\nFull trace: {}".format(
+              error.output if error.output is not None else "(not captured)",
+              args,
+              traceback.format_exc())) from error
     return out
 
   def Popen(*args, **kwargs):

sdks/python/apache_beam/utils/processes_test.py

@@ -121,15 +121,25 @@ def test_check_call_pip_install_non_existing_package(self):
     self.mock_get.side_effect = subprocess.CalledProcessError(returncode,\
       cmd, output=output)
     try:
-      output = processes.check_call(cmd)
+      processes.check_call(cmd)
       self.fail(
-          "The test failed due to that\
-        no error was raised when calling process.check_call")
+          "The test failed due to that "
+          "no error was raised when calling process.check_call")
     except RuntimeError as error:
-      self.assertIn("Output from execution of subprocess: {}".format(output),\
-        error.args[0])
-      self.assertIn("Pip install failed for package: {}".format(package),\
-        error.args[0])
+      self.assertIn("Output from execution of subprocess:", error.args[0])
+      self.assertIn(output, error.args[0])
+
+  def test_check_call_pip_short_command_no_index_error(self):
+    """Short pip command (e.g. pip install pkg) must not raise IndexError."""
+    returncode = 1
+    cmd = ['python', '-m', 'pip', 'install', 'nonexistent-package-xyz']
+    output = "ERROR: Could not find a version that satisfies"
+    self.mock_get.side_effect = subprocess.CalledProcessError(
+        returncode, cmd, output=output)
+    with self.assertRaises(RuntimeError) as ctx:
+      processes.check_call(cmd)
+    self.assertIn("Output from execution of subprocess:", ctx.exception.args[0])
+    self.assertIn(output, ctx.exception.args[0])
 
 
 class TestErrorHandlingCheckOutput(unittest.TestCase):
@@ -162,15 +172,25 @@ def test_check_output_pip_install_non_existing_package(self):
     self.mock_get.side_effect = subprocess.CalledProcessError(returncode,\
          cmd, output=output)
     try:
-      output = processes.check_output(cmd)
+      processes.check_output(cmd)
       self.fail(
-          "The test failed due to that\
-      no error was raised when calling process.check_call")
+          "The test failed due to that "
+          "no error was raised when calling process.check_output")
     except RuntimeError as error:
-      self.assertIn("Output from execution of subprocess: {}".format(output),\
-        error.args[0])
-      self.assertIn("Pip install failed for package: {}".format(package),\
-        error.args[0])
+      self.assertIn("Output from execution of subprocess:", error.args[0])
+      self.assertIn(output, error.args[0])
+
+  def test_check_output_pip_short_command_no_index_error(self):
+    """Short pip command must not raise IndexError."""
+    returncode = 1
+    cmd = ['python', '-m', 'pip', 'install', 'nonexistent-package-xyz']
+    output = "ERROR: Could not find a version"
+    self.mock_get.side_effect = subprocess.CalledProcessError(
+        returncode, cmd, output=output)
+    with self.assertRaises(RuntimeError) as ctx:
+      processes.check_output(cmd)
+    self.assertIn("Output from execution of subprocess:", ctx.exception.args[0])
+    self.assertIn(output, ctx.exception.args[0])
 
 
 class TestErrorHandlingCall(unittest.TestCase):
@@ -193,7 +213,7 @@ def test_oserror_check_output_message(self):
       self.assertIn('Executable {} not found'.format(str(cmd)),\
       error.args[0])
 
-  def test_check_output_pip_install_non_existing_package(self):
+  def test_call_pip_install_non_existing_package(self):
     returncode = 1
     package = "non-exsisting-package"
     cmd = ['python', '-m', 'pip', 'download', '--dest', '/var',\
@@ -203,15 +223,25 @@ def test_check_output_pip_install_non_existing_package(self):
     self.mock_get.side_effect = subprocess.CalledProcessError(returncode,\
          cmd, output=output)
     try:
-      output = processes.call(cmd)
+      processes.call(cmd)
       self.fail(
-          "The test failed due to that\
-        no error was raised when calling process.check_call")
+          "The test failed due to that "
+          "no error was raised when calling process.call")
     except RuntimeError as error:
-      self.assertIn("Output from execution of subprocess: {}".format(output),\
-        error.args[0])
-      self.assertIn("Pip install failed for package: {}".format(package),\
-        error.args[0])
+      self.assertIn("Output from execution of subprocess:", error.args[0])
+      self.assertIn(output, error.args[0])
+
+  def test_call_pip_short_command_no_index_error(self):
+    """Short pip command must not raise IndexError."""
+    returncode = 1
+    cmd = ['python', '-m', 'pip', 'install', 'nonexistent-package-xyz']
+    output = "ERROR: Could not find a version"
+    self.mock_get.side_effect = subprocess.CalledProcessError(
+        returncode, cmd, output=output)
+    with self.assertRaises(RuntimeError) as ctx:
+      processes.call(cmd)
+    self.assertIn("Output from execution of subprocess:", ctx.exception.args[0])
+    self.assertIn(output, ctx.exception.args[0])
 
 
 if __name__ == '__main__':