How can I define a tokenURL that will generate the 'Absolute' authentication URL as per user selection of a 'host' from the host list in swagger UI?

Question

I have a spring boot application for which I am trying to generate open API 3.0 docs and for that I am using springdoc lib. I am using annotations to document different parts of the application and in the end I want to auto generate the documentation. I am using annotations for all documentations and finding it a little difficult to replicate similar things listed in yaml/json from the official documentation of springdocs. I have multiple instances of the app and will be uploading the documentation for all of them to a single open API UI. For the multiple hosts, I have defined them something like below:

@OpenAPIDefinition(
    info = @Info(
        title = "Title",
        version = "v1",
        description = "Desc",

    ),
    servers = {
        @Server(
            url = "https://server-1.com",
            description = "Server 1"
        ),
        @Server(
            url = "https://server-2.com",
            description = "Server 2"
        ),
        @Server(
            url = "https://server-3.com",
            description = "Server 3"
        )
    }
)
@SecurityScheme(name = "security_auth", type = SecuritySchemeType.OAUTH2,
    flows = @OAuthFlows(authorizationCode =
    @OAuthFlow(tokenUrl = "v1/authenticate")))
public class OpenAPIConfig {}

Now the issue for me is that the toeken URL shows up like defined above whole I want to define the absolute URL, something that will be updated as per user selection. For eg - https://server-3.com/v1/authenticate. How can I do that within annotations ?

Answer 1

You should declare 3 different SecurityScheme for your sample. Note that all the server urls/paths could be fetch fron a configuration file as well.

Here a sample code how you can achieve your goal:

import io.swagger.v3.oas.models.Components;
import io.swagger.v3.oas.models.OpenAPI;
import io.swagger.v3.oas.models.info.Info;
import io.swagger.v3.oas.models.security.OAuthFlow;
import io.swagger.v3.oas.models.security.OAuthFlows;
import io.swagger.v3.oas.models.security.SecurityScheme.Type;
import io.swagger.v3.oas.models.servers.Server;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class OpenAPIConfig {

    @Bean
    public OpenAPI openAPIDef() {
        String serverUrl1 = "https://server-1.com";
        String serverUrl2 = "https://server-2.com";
        String serverUrl3 = "https://server-3.com";
        String suffix = "/v1/authenticate";

        return new OpenAPI().info(new Info().title("Title").version("v1"))
                .addServersItem(new Server().url(serverUrl1))
                .addServersItem(new Server().url(serverUrl2))
                .addServersItem(new Server().url(serverUrl3))
                .components(new Components()
                        .addSecuritySchemes("security_auth_server1",
                                new io.swagger.v3.oas.models.security.SecurityScheme()
                                        .type(Type.OAUTH2)
                                        .flows(new OAuthFlows().authorizationCode(new OAuthFlow().tokenUrl(serverUrl1 + suffix))))
                        .addSecuritySchemes("security_auth_server2",
                                new io.swagger.v3.oas.models.security.SecurityScheme()
                                        .type(Type.OAUTH2)
                                        .flows(new OAuthFlows().authorizationCode(new OAuthFlow().tokenUrl(serverUrl2 + suffix))))
                        .addSecuritySchemes("security_auth_server3",
                                new io.swagger.v3.oas.models.security.SecurityScheme()
                                        .type(Type.OAUTH2)
                                        .flows(new OAuthFlows().authorizationCode(new OAuthFlow().tokenUrl(serverUrl3 + suffix)))));
    }
}