Custom domain name for REST APIs in API Gateway
Custom domain names are simpler and more intuitive URLs that you can provide to your API users.
After deploying your API, you (and your customers) can invoke the API using the default base URL of the following format:
https://api-id.execute-api.region.amazonaws.com/stage
where api-id is generated by API Gateway, region is the Amazon Region,
and stage is specified by you when deploying the
API.
The hostname portion of the URL,
api-id.execute-api.region.amazonaws.com
With custom domain names, you can set up your API's hostname, and choose a base path (for
example, myservice) to map the alternative URL to your API. For example, a more
user-friendly API base URL can become:
https://api.example.com/myservice
Considerations
The following considerations might impact your use of a custom domain name.
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Custom domain names are not supported for private APIs.
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You can disable the default endpoint for your API. Clients can still connect to your default endpoint, but they will receive a
403 Forbiddenstatus code. -
A Regional custom domain name can be can be associated with REST APIs and HTTP APIs. You can use the API Gateway Version 2 APIs to create and manage Regional custom domain names for REST APIs.
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A custom domain name must be unique within a Region across all Amazon accounts.
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You can migrate your custom domain name between edge-optimized and Regional endpoints.
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You must create or update your DNS provider's resource record to map to your API endpoint. Without such a mapping, API requests bound for the custom domain name cannot reach API Gateway.
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You can support an almost infinite number of domain names without exceeding the default quota by using a wildcard certificate. For more information, see Wildcard custom domain names.
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You can choose a security policy for your custom domain name. For more information, see Choose a security policy for your REST API custom domain in API Gateway.
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To configure API mappings with multiple levels, you must use a Regional custom domain name and use the TLS 1.2 security policy.
Prerequisites
The following are prerequisites for creating a custom domain name.
Register a domain name
You must have a registered internet domain name in order to set up custom domain names for your APIs. You can register your internet domain name using Amazon Route 53 or using a third-party domain registrar of your choice. Your custom domain name can be the name of a subdomain or the root domain (also known as the "zone apex") of a registered internet domain.
Your domain name must follow the RFC
1035
Specify the certificate for your custom domain name
Before setting up a custom domain name for an API, you must have an SSL/TLS certificate ready in ACM. If ACM is not available in the Amazon Region where you are creating your custom domain name, you must import a certificate to API Gateway in that Region.
To import an SSL/TLS certificate, you must provide the PEM-formatted SSL/TLS certificate body, its private key, and the certificate chain for the custom domain name.
Each certificate stored in ACM is identified by its ARN. With certificates issued by ACM, you do not have to worry about exposing any sensitive certificate details, such as the private key. To use an Amazon managed certificate for a domain name, you simply reference its ARN.
If your application uses certificate pinning, sometimes known as SSL pinning, to pin an ACM certificate, the application might not be able to connect to your domain after Amazon renews the certificate. For more information, see Certificate pinning problems in the Amazon Certificate Manager User Guide.
Wildcard custom domain names
With wildcard custom domain names, you can support an almost infinite number of domain names without exceeding the default quota. For
example, you could give each of your customers their own domain name, customername.api.example.com
To create a wildcard custom domain name, specify a wildcard
(*) as the first subdomain of a custom domain that represents all
possible subdomains of a root domain.
For example, the wildcard custom domain name *.example.com results in
subdomains such as a.example.com, b.example.com, and
c.example.com, which all route to the same domain.
Wildcard custom domain names support distinct configurations from API Gateway's standard
custom domain names. For example, in a single Amazon account, you can configure
*.example.com and a.example.com to behave
differently.
You can use the $context.domainName and
$context.domainPrefix context variables to determine the domain name
that a client used to call your API. To learn more about context variables, see API Gateway mapping template and access
logging variable reference.
To create a wildcard custom domain name, you must provide a certificate issued by ACM that has been validated using either the DNS or the email validation method.
Note
You can't create a wildcard custom domain name if a different Amazon account has
created a custom domain name that conflicts with the wildcard custom domain name.
For example, if account A has created a.example.com, then account B
can't create the wildcard custom domain name *.example.com.
If account A and account B share an owner, you can contact the Amazon Support Center
Next steps for custom domain names
The following are next steps for custom domain names:
Next steps
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To learn how to set your SSL/TLS certificate, see Get certificates ready in Amazon Certificate Manager.
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To learn how to create a Regional custom domain name, see Set up a Regional custom domain name in API Gateway.
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To learn how to create an edge-optimized custom domain name, see Set up an edge-optimized custom domain name in API Gateway.
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To learn how to migrate between Regional and edge-optimized custom domain names, see Migrate a custom domain name to a different API endpoint type.
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To learn how to connect API stages to a custom domain name, see Map API stages to a custom domain name.
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To learn how to choose a security policy for your custom domain name, see Choose a security policy for your REST API custom domain in API Gateway.
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To learn how to turn off the default endpoint for your custom domain name, see Disable the default endpoint for REST APIs.
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To learn how to use Route 53 health checks to control DNS failover from an API Gateway API, see Configure custom health checks for DNS failover.
If this is your first time creating a custom domain name, we recommend that you start with Get certificates ready in Amazon Certificate Manager, to specify your certificate, and then Set up a Regional custom domain name in API Gateway to create a Regional custom domain name.