fix retry logic failures (#5137)

* fix retry logic failures

* changelog

* add tests to make sure data is getting where it needs to

* rename file

* remove duplicate file

.changes/unreleased/Fixes-20220422-131227.yaml

@@ -0,0 +1,7 @@
+kind: Fixes
+body: Fix retry logic to return values after initial try
+time: 2022-04-22T13:12:27.239055-05:00
+custom:
+  Author: emmyoop
+  Issue: "5023"
+  PR: "5137"

core/dbt/utils.py

@@ -614,6 +614,6 @@ def _connection_exception_retry(fn, max_attempts: int, attempt: int = 0):
             fire_event(RecordRetryException(exc=exc))
             fire_event(RetryExternalCall(attempt=attempt, max=max_attempts))
             time.sleep(1)
-            _connection_exception_retry(fn, max_attempts, attempt + 1)
+            return _connection_exception_retry(fn, max_attempts, attempt + 1)
         else:
             raise ConnectionException('External connection exception occurred: ' + str(exc))

tests/unit/test_connection_retries.py

@@ -0,0 +1,59 @@
+import functools
+import pytest
+from requests.exceptions import RequestException
+from dbt.exceptions import ConnectionException
+from dbt.utils import _connection_exception_retry
+
+
+def no_retry_fn():
+    return "success"
+
+
+class TestNoRetries:
+    def test_no_retry(self):
+        fn_to_retry = functools.partial(no_retry_fn)
+        result = _connection_exception_retry(fn_to_retry, 3)
+
+        expected = "success"
+
+        assert result == expected
+
+
+def no_success_fn():
+    raise RequestException("You'll never pass")
+    return "failure"
+
+
+class TestMaxRetries:
+    def test_no_retry(self):
+        fn_to_retry = functools.partial(no_success_fn)
+
+        with pytest.raises(ConnectionException):
+            _connection_exception_retry(fn_to_retry, 3)
+
+
+def single_retry_fn():
+    global counter
+    if counter == 0:
+        counter += 1
+        raise RequestException("You won't pass this one time")
+    elif counter == 1:
+        counter += 1
+        return "success on 2"
+
+    return "How did we get here?"
+
+
+class TestSingleRetry:
+    def test_no_retry(self):
+        global counter
+        counter = 0
+
+        fn_to_retry = functools.partial(single_retry_fn)
+        result = _connection_exception_retry(fn_to_retry, 3)
+        expected = "success on 2"
+
+        # We need to test the return value here, not just that it did not throw an error.
+        # If the value is not being passed it causes cryptic errors
+        assert result == expected
+        assert counter == 2