Add an Option to disable retries

include/aws/io/retry_strategy.h

@@ -106,14 +106,16 @@ enum aws_exponential_backoff_jitter_mode {
  * "use defaults"
  */
 struct aws_exponential_backoff_retry_options {
-    /** Event loop group to use for scheduling tasks. */
+    /* Event loop group to use for scheduling tasks. */
     struct aws_event_loop_group *el_group;
-    /** Max retries to allow. The default value is 10 */
+    /* Max retries to allow. The default value is 10 */
     size_t max_retries;
-    /** Scaling factor to add for the backoff. Default is 500ms */
+    /* Scaling factor to add for the backoff. Default is 500ms */
     uint32_t backoff_scale_factor_ms;
-    /** Max retry backoff in seconds. Default is 20 seconds */
+    /* Max retry backoff in seconds. Default is 20 seconds */
     uint32_t max_backoff_secs;
+    /* Disables retries completely. Attempts to acquire_token will fail with `AWS_IO_RETRY_PERMISSION_DENIED` */
+    bool no_retries;
     /** Jitter mode to use, see comments for aws_exponential_backoff_jitter_mode.
      * Default is AWS_EXPONENTIAL_BACKOFF_JITTER_DEFAULT */
     enum aws_exponential_backoff_jitter_mode jitter_mode;

source/exponential_backoff_retry_strategy.c

@@ -27,6 +27,7 @@ struct exponential_backoff_retry_token {
     size_t max_retries;
     uint64_t backoff_scale_factor_ns;
     uint64_t maximum_backoff_ns;
+    bool no_retries;
     enum aws_exponential_backoff_jitter_mode jitter_mode;
     /* Let's not make this worse by constantly moving across threads if we can help it */
     struct aws_event_loop *bound_loop;
@@ -115,6 +116,10 @@ static int s_exponential_retry_acquire_token(
     (void)partition_id;
     /* no resource contention here so no timeouts. */
     (void)timeout_ms;
+    struct exponential_backoff_strategy *exponential_backoff_strategy = retry_strategy->impl;
+    if (exponential_backoff_strategy->config.no_retries) {
+        return aws_raise_error(AWS_IO_RETRY_PERMISSION_DENIED);
+    }
 
     struct exponential_backoff_retry_token *backoff_retry_token =
         aws_mem_calloc(retry_strategy->allocator, 1, sizeof(struct exponential_backoff_retry_token));
@@ -135,7 +140,6 @@ static int s_exponential_retry_acquire_token(
     aws_retry_strategy_acquire(retry_strategy);
     backoff_retry_token->base.impl = backoff_retry_token;
 
-    struct exponential_backoff_strategy *exponential_backoff_strategy = retry_strategy->impl;
     backoff_retry_token->bound_loop = aws_event_loop_group_get_next_loop(exponential_backoff_strategy->config.el_group);
     backoff_retry_token->max_retries = exponential_backoff_strategy->config.max_retries;
     backoff_retry_token->backoff_scale_factor_ns = aws_timestamp_convert(

tests/CMakeLists.txt

@@ -316,6 +316,7 @@ add_test_case(test_exponential_backoff_retry_client_errors_do_not_count)
 add_test_case(test_exponential_backoff_retry_no_jitter_time_taken)
 add_test_case(test_exponential_max_backoff_retry_no_jitter)
 add_test_case(test_exponential_backoff_retry_invalid_options)
+add_test_case(test_exponential_backoff_no_retries)
 
 add_test_case(test_standard_retry_strategy_setup_shutdown)
 add_test_case(test_standard_retry_strategy_failure_exhausts_bucket)

tests/exponential_backoff_retry_test.c

@@ -327,3 +327,45 @@ static int s_test_exponential_backoff_retry_invalid_options_fn(struct aws_alloca
     return AWS_OP_SUCCESS;
 }
 AWS_TEST_CASE(test_exponential_backoff_retry_invalid_options, s_test_exponential_backoff_retry_invalid_options_fn)
+
+static int s_test_exponential_backoff_no_retries_fn(struct aws_allocator *allocator, void *ctx) {
+    (void)ctx;
+
+    aws_io_library_init(allocator);
+
+    struct aws_event_loop_group *el_group = aws_event_loop_group_new_default(allocator, 1, NULL);
+    struct aws_exponential_backoff_retry_options config = {
+        .max_retries = 3,
+        .no_retries = true,
+        .el_group = el_group,
+    };
+
+    struct aws_retry_strategy *retry_strategy = aws_retry_strategy_new_exponential_backoff(allocator, &config);
+    ASSERT_NOT_NULL(retry_strategy);
+
+    struct exponential_backoff_test_data test_data = {
+        .retry_count = 0,
+        .failure_error_code = 0,
+        .mutex = AWS_MUTEX_INIT,
+        .cvar = AWS_CONDITION_VARIABLE_INIT,
+    };
+
+    ASSERT_SUCCESS(aws_mutex_lock(&test_data.mutex));
+    ASSERT_ERROR(
+        AWS_IO_RETRY_PERMISSION_DENIED,
+        aws_retry_strategy_acquire_retry_token(
+            retry_strategy, NULL, s_too_many_retries_test_token_acquired, &test_data, 0));
+
+    aws_mutex_unlock(&test_data.mutex);
+
+    ASSERT_UINT_EQUALS(0, test_data.retry_count);
+
+    aws_retry_strategy_release(retry_strategy);
+    aws_event_loop_group_release(el_group);
+
+    aws_io_library_clean_up();
+
+    return AWS_OP_SUCCESS;
+}
+
+AWS_TEST_CASE(test_exponential_backoff_no_retries, s_test_exponential_backoff_no_retries_fn)