API to retrieve list of platform with recommended configuration (#367)

include/aws/s3/private/s3_platform_info.h

@@ -44,6 +44,13 @@ AWS_S3_API
 const struct aws_s3_platform_info *aws_s3_get_platform_info_for_current_environment(
     struct aws_s3_platform_info_loader *loader);
 
+/*
+ * Retrieves a list of EC2 instance types with recommended configuration.
+ * Returns aws_array_list<aws_byte_cursor>. The caller is responsible for cleaning up the array list.
+ */
+AWS_S3_API
+struct aws_array_list aws_s3_get_recommended_platforms(struct aws_s3_platform_info_loader *loader);
+
 /**
  * Returns true if the current process is running on an Amazon EC2 instance powered by Nitro.
  */

include/aws/s3/s3.h

@@ -113,6 +113,13 @@ void aws_s3_library_clean_up(void);
 AWS_S3_API
 const struct aws_s3_platform_info *aws_s3_get_current_platform_info(void);
 
+/*
+ * Retrieves a list of EC2 instance types with recommended configuration.
+ * Returns aws_array_list<aws_byte_cursor>. The caller is responsible for cleaning up the array list.
+ */
+AWS_S3_API
+struct aws_array_list aws_s3_get_platforms_with_recommended_config(void);
+
 AWS_EXTERN_C_END
 AWS_POP_SANE_WARNING_LEVEL
 

source/s3.c

@@ -98,6 +98,10 @@ const struct aws_s3_platform_info *aws_s3_get_current_platform_info(void) {
     return aws_s3_get_platform_info_for_current_environment(s_loader);
 }
 
+struct aws_array_list aws_s3_get_platforms_with_recommended_config(void) {
+    return aws_s3_get_recommended_platforms(s_loader);
+}
+
 void aws_s3_library_clean_up(void) {
     if (!s_library_initialized) {
         return;

source/s3_platform_info.c

@@ -569,6 +569,25 @@ const struct aws_s3_platform_info *aws_s3_get_platform_info_for_current_environm
     return &loader->lock_data.current_env_platform_info;
 }
 
+struct aws_array_list aws_s3_get_recommended_platforms(struct aws_s3_platform_info_loader *loader) {
+    struct aws_array_list array_list;
+    aws_mutex_lock(&loader->lock_data.lock);
+    aws_array_list_init_dynamic(&array_list, loader->allocator, 5, sizeof(struct aws_byte_cursor));
+    /* Iterate over the map and add instance types to the array list which have
+     * platform_info->has_recommended_configuration == true */
+    for (struct aws_hash_iter iter = aws_hash_iter_begin(&loader->lock_data.compute_platform_info_table);
+         !aws_hash_iter_done(&iter);
+         aws_hash_iter_next(&iter)) {
+        struct aws_s3_platform_info *platform_info = iter.element.value;
+
+        if (platform_info->has_recommended_configuration) {
+            aws_array_list_push_back(&array_list, &platform_info->instance_type);
+        }
+    }
+    aws_mutex_unlock(&loader->lock_data.lock);
+    return array_list;
+}
+
 const struct aws_s3_platform_info *aws_s3_get_platform_info_for_instance_type(
     struct aws_s3_platform_info_loader *loader,
     struct aws_byte_cursor instance_type_name) {

tests/CMakeLists.txt

@@ -189,6 +189,7 @@ add_test_case(test_add_user_agent_header)
 
 add_test_case(test_get_existing_platform_info)
 add_test_case(test_get_nonexistent_platform_info)
+add_test_case(test_get_platforms_with_recommended_config)
 add_net_test_case(load_platform_info_from_global_state_sanity_test)
 
 add_net_test_case(sha1_nist_test_case_1)

tests/s3_platform_info_test.c

@@ -97,3 +97,22 @@ static int s_load_platform_info_from_global_state_sanity_test(struct aws_allocat
 }
 
 AWS_TEST_CASE(load_platform_info_from_global_state_sanity_test, s_load_platform_info_from_global_state_sanity_test)
+
+static int s_test_get_platforms_with_recommended_config(struct aws_allocator *allocator, void *ctx) {
+    (void)ctx;
+
+    aws_s3_library_init(allocator);
+
+    struct aws_array_list recommended_platform_list = aws_s3_get_platforms_with_recommended_config();
+    ASSERT_TRUE(aws_array_list_length(&recommended_platform_list) > 0);
+    for (size_t i = 0; i < aws_array_list_length(&recommended_platform_list); ++i) {
+        struct aws_byte_cursor cursor;
+        aws_array_list_get_at(&recommended_platform_list, &cursor, i);
+        ASSERT_TRUE(cursor.len > 0);
+    }
+    aws_array_list_clean_up(&recommended_platform_list);
+    aws_s3_library_clean_up();
+    return AWS_OP_SUCCESS;
+}
+
+AWS_TEST_CASE(test_get_platforms_with_recommended_config, s_test_get_platforms_with_recommended_config)