API Gateway:Backend service types

Internal domain name resolution for backend services (only for dedicated instances)

API Gateway supports internal domain names for backend services and provides instance-level domain name resolution. Specifically:

• Overview: You can configure weights for resolution records in API Gateway.

• Steps to configure an internal domain name resolution.

• Usage notes: the items to which you must pay attention during configuration. This ensures smooth configuration.

• Limits: the restrictions and limitations when you use the feature.

For more information, see Internal domain name resolution for backend services (only for dedicated instances).

Resources in VPCs

Elastic Compute Service (ECS) instances and Classic Load Balancer (CLB) instances in a VPC can both be used as backend services of APIs. Specifically:

• Use a resource in a VPC as the backend service of an API

  • Authorize access to and bind your VPC: To create an API by using a resource in a VPC, you must first authorize API Gateway to access the resource. During the authorization, you must specify the resource and port that you want API Gateway to access. This ensures that API Gateway can securely communicate with your service.

  • Build a high-availability architecture: You must build a high-availability API architecture to ensure system reliability and stability. The topic to which the link directs provides detailed instructions.

  • FAQ: The topic also provides answers to some commonly asked questions about the configuration. This helps you smoothly complete the configuration.

• Test the network connectivity of a VPC access authorization

  In this step, you test the network connectivity between your API Gateway instance and the resource to be accessed in your VPC. This test helps identify and resolve API call issues caused by network connectivity in advance during API debugging.

For more information, see Resources in VPCs.

Function Compute

API Gateway allows you to use Function Compute as the backend service of an API. Specifically:

• Overview.

  An API Gateway instance is created. For more information about instance types, see Choose an instance type.

• Steps to integrate an HTTP function into API Gateway.

• Steps to integrate an event function into API Gateway.

• FAQ.

For more information, see Function Compute.

Mock

API Gateway allows you to use Mock as the backend service of an API. The Mock service simulates responses to API calls based on API configurations. This reduces miscommunication and misunderstanding among team members and improves development efficiency. Specifically:

• Configure Mock.

• Remove Mock.

For more information, see Mock.

Data services

API Gateway allows you to configure a data service as the backend service of an API. Data services are designed to build a uniform data service bus to help enterprises increase the value of their data assets as well as guarantee data reliability, security, and effectiveness.

• Data services are applicable to the following scenarios:

  • Minimize data exposure.

  • Connect visualization tools to databases.

  • Provide processed data for applications.

• Alibaba Cloud services that provide data services:

  • Big data services: DataService Studio. For more information, see Overview.

  • Database services: Data Management (DMS). For more information, see Overview.

For more information, see Create APIs for data services.

PAI

Alibaba Cloud Platform for AI (PAI) Elastic Algorithm Service (EAS) allows you to publish models to API Gateway by using REST APIs. Models that are published to API Gateway can be called in business systems by using HTTP requests. For information about the call, see Call a service over a public endpoint. For more information, see PAI.

EventBridge

API Gateway supports EventBridge as an API backend service. Specifically:

• Steps to create and publish an API with EventBridge as the backend service.

• Steps to call the API by using an application and an AppCode based on the Alibaba Cloud App authentication method.

For more information, see EventBridge.

Microservices registries

API Gateway supports microservice registries as backend services. Specifically:

• Nacos

  • How API Gateway is integrated with Nacos to access backend microservices applications.

  • How to create a virtual private cloud (VPC) integration instance.

  • How to deploy Nacos and register a microservices application with Nacos.

• Zookeeper

  • How API Gateway is integrated with ZooKeeper to access backend microservices applications.

  • How to create a VPC integration instance.

  • How to deploy ZooKeeper and register a microservices application with ZooKeeper.

For more information, see Microservices registries.

API gateways in multiple levels

APIs that are created in API Gateway can be called by clients and also by API Gateway itself. This improves API service flexibility and functionality and meets diverse needs in different scenarios. Specifically:

• in the same region over internal networks or across regions over the Internet.

• API Gateway can call APIs that belong to the same account or a different account.

For more information, see API gateways in multiple levels.

Configure the Host header

API Gateway allows you to configure the Host header to specify to which backend service API Gateway forwards requests. Specifically:

• How to configure the Host header.

• Priority of Host header configurations.

For more information, see Configure the Host header.