apigateway: support custom domains

[eladb]

Missing capability in API gateway (#723)

[eladb]

WIP

[moravcik]

I'm trying to map my RestApi to existing domain name (created earlier and mapped to multiple rest APIs) with following code:

  const domainName = DomainName.fromDomainNameAttributes(this, 'MyApiDomain', {
    domainName: 'my.existing.domain.name',
    domainNameAliasTarget: 'XXX,       // I would prefer having this property as optional
    domainNameAliasHostedZoneId: 'YYY' // I would prefer having this property as optional
  });
  domainName.addBasePathMapping(myRestApi, { basePath: 'mymapping' });

and I am getting following error (when compiling cdk code):

Property 'addBasePathMapping' does not exist on type 'IDomainName'.

or when I retype domainName as DomainName (on cdk synth, cdk diff or cdk deploy):

TypeError: domainName.addBasePathMapping is not a function

Are there any plans to address such case? I am using CDK version 0.36.2

[jderose9]

It seems odd that the default endpoint type is REGIONAL. It seems that most users that are making a public API with custom domain name would benefit from choosing EDGE instead, which is the default selection when using the console.

[eladb]

Thanks for this feedback. This makes sense to me. I'll open an issue

[f-Stabby]

I am also running into the issue referenced above but not responded to.
#3103 (comment)

I can import an existing custom domain mapping with the from_domain_name_attributes, but there is no add_base_path_mapping method on IDomainNames for some reason, so I can do nothing with it.

Any solution?

[jderose9]

@moravcik @f-Stabby

I'm not really sure what fromDomainNameAttributes is for, but I was able to add a base path mapping this way:

const domain = new apigw.DomainName(this, 'myApiDomain', {
  domainName: "api.mydomain.com",
  certificate: acm.Certificate.fromCertificateArn(this, "myApiDomainCertificate", "<cert arn>"),
  endpointType: apigw.EndpointType.EDGE
});

domain.addBasePathMapping(api, { basePath: 'v1'});

Hope that helps somehow!

[f-Stabby]

FromDomainNameAttributes should be like the other "fromxx" functions that exist in most constructs in that, it is for referencing a resource that already exists.

Rather than deleting a preexisting resource and recreating it, I would like to be able to reference the domain name using FromDomainNameAttributes, then add a base path mapping to it.

Hope this gives more context.
@jderose9

[devarpi-zz]

@moravcik @f-Stabby

I'm not really sure what fromDomainNameAttributes is for, but I was able to add a base path mapping this way:

const domain = new apigw.DomainName(this, 'myApiDomain', {
  domainName: "api.mydomain.com",
  certificate: acm.Certificate.fromCertificateArn(this, "myApiDomainCertificate", "<cert arn>"),
  endpointType: apigw.EndpointType.EDGE
});

domain.addBasePathMapping(api, { basePath: 'v1'});

Hope that helps somehow!

We need to add new api to existing custom domain. This will create new domain. Is there a way to do that?

[JoshM1994]

@devarpi

We need to add new api to existing custom domain. This will create new domain. Is there a way to do that?

I believe if you follow a similar pattern but instead of using new apigw.DomainName... you use:

const domain = apigw.DomainName.fromDomainNameAttributes(...)

then you should be able to use a domain which already exists.

[mbsimonovic]

@JoshM1994 read the comments above, fromDomainNameAttributes returns the interface IDomainName which does not have this property addBasePathMapping. Casting it to the class results in a runtime error TypeError: domainName.addBasePathMapping is not a function. So seems like there's no way to do this?

[kamaz]

@mbsimonovic yes, it is possible.

Instead of using new DomainName() you have to use DomainName.fromDomainNameAttributes and then define BasePathMapping.

Example below, I hope it helps:

const api = new RestApi(this, "rest-api", {}); 

const domainName = DomainName.fromDomainNameAttributes(this, "dev-example", {
   domainName: "dev.example.com",
   domainNameAliasHostedZoneId: "",
   domainNameAliasTarget: ""
});

new BasePathMapping(this, "path-mapping-users", {
      basePath: "users",
      domainName: domainName,
      restApi: api
});

[roitman-g]

What is domainNameAliasTarget in domain name attributes?

[uglow]

@roitman-g I found the answer to to your question here

[BwL1289]

@roitman-g and for anyone else out there trying to figure out how to get domainNameAliasTarget programmatically in CDK -- from what I've found, there's no good way.

The answer here is correct, but unless I'm mistaken, it doesn't seem there's a way to grab it as a property from any other resource construct (except after you create the custom domain in CDK like new_custom_domain_name.domain_name_alias_domain_name, for example).

There may be a good reason for this under the hood, but not sure.

Best alternative I found is saving as an SSM parameter in CDK when I create the custom domain and importing it thereafter.

If @eladb you know of (or if anyone finds one) a better way, please let me know.