Filter out deprecation warnings from reported stderr

salt/client/ssh/wrapper/__init__.py

@@ -31,13 +31,31 @@ class SSHException(SaltException):
     ):
         super().__init__(stderr, *args, **kwargs)
         self.stdout = stdout
-        self.stderr = stderr
+        self.stderr = self._filter_stderr(stderr)
         self.result = result
         self.data = data
         self.retcode = retcode
         if args:
             self._error = args.pop(0)
 
+    def _filter_stderr(self, stderr):
+        stderr_lines = []
+        skip_next = False
+        for line in stderr.splitlines():
+            if skip_next:
+                skip_next = False
+                continue
+            # Filter out deprecation warnings from stderr to the best of
+            # our ability since they are irrelevant to the command output and cause noise.
+            parts = line.split(":")
+            if len(parts) > 2 and "DeprecationWarning" in parts[2]:
+                # DeprecationWarnings print two lines, the second one being the
+                # line that caused the warning.
+                skip_next = True
+                continue
+            stderr_lines.append(line)
+        return "\n".join(stderr_lines)
+
     def to_ret(self):
         ret = {
             "stdout": self.stdout,

tests/pytests/integration/ssh/test_deploy.py

@@ -220,9 +220,11 @@ def test_retcode_exe_run_fail(salt_ssh_cli):
     """
     ret = salt_ssh_cli.run("file.touch", "/tmp/non/ex/is/tent")
     assert ret.returncode == EX_AGGREGATE
-    assert isinstance(ret.data, dict)
-    assert "Error running 'file.touch': No such file or directory" in ret.data["stderr"]
     assert ret.data["retcode"] == 1
+    assert isinstance(ret.data, str)
+    # This should be the exact output, but some other warnings
+    # might be printed to stderr.
+    assert "Error running 'file.touch': No such file or directory" in ret.data
 
 
 def test_retcode_exe_run_exception(salt_ssh_cli):