springdoc-openapi apply default global SecurityScheme possible?

Tested with v1.2.29 of springdoc-openapi: Its possible to disable security for particular Endpoint using: @SecurityRequirements

@GetMapping("/open")
@ResponseBody
@SecurityRequirements
public String open() {
    return "It works!";
}

For older versions, for example tested with v1.2.28 using OperationCustomizer:

public static final String UNSECURED = "security.open";

@Bean
public OperationCustomizer customize() {
    return (Operation operation, HandlerMethod handlerMethod) -> {
        List<String> tags = operation.getTags();
        if (tags != null && tags.contains(UNSECURED)) {
            operation.setSecurity(Collections.emptyList());
            operation.setTags(tags.stream()
                    .filter(t -> !t.equals(UNSECURED))
                    .collect(Collectors.toList()));
        }
        return operation;
    };
}

Yes, you can do it in the same place calling addSecurityItem:

  @Bean
  public OpenAPI customOpenAPI() {
    return new OpenAPI()
            .components(new Components().addSecuritySchemes("bearer-jwt",
                new SecurityScheme().type(SecurityScheme.Type.HTTP).scheme("bearer").bearerFormat("JWT")
                    .in(SecurityScheme.In.HEADER).name("Authorization")))
            .info(new Info().title("App API").version("snapshot"))
            .addSecurityItem(
                    new SecurityRequirement().addList("bearer-jwt", Arrays.asList("read", "write")));
  }

Global security schema can be overridden by a different one with the @SecurityRequirements annotation. Including removing security schemas for an operation. For example, we can remove security for registration path.

@SecurityRequirements
@PostMapping("/registration")
public ResponseEntity post(@RequestBody @Valid Registration: registration) {
    return registrationService.register(registration);
}

While still keeping security schemas for other APIs.

Old answer (Dec 20 '19):

Global security schema can be overridden by a different one with the @SecurityRequirements annotation. but it cannot be removed for unsecured paths. It is acctualy missing fueature in the springdoc-openapi, OpenAPI standard allows it. See disable global security for particular operation

There is a workaround though. The springdoc-openapi has a concept of an OpenApiCustomiser which can be used to intercept generated schema. Inside the customizer, an operation can be modified programmatically. To remove any inherited security, the field security needs to be set to an empty array. The logic may be based on any arbitrary rules e.g operation name. I used tags.

The customizer:

import io.swagger.v3.oas.models.OpenAPI;
import io.swagger.v3.oas.models.Operation;
import io.swagger.v3.oas.models.PathItem;
import org.springdoc.api.OpenApiCustomiser;
import org.springframework.stereotype.Component;

import javax.validation.constraints.NotNull;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import java.util.function.Function;
import java.util.stream.Collectors;
import java.util.stream.Stream;

@Component
public class SecurityOverrideCustomizer implements OpenApiCustomiser {

    public static final String UNSECURED = "security.open";

    private static final List<Function<PathItem, Operation>> OPERATION_GETTERS = Arrays.asList(
            PathItem::getGet, PathItem::getPost, PathItem::getDelete, PathItem::getHead,
            PathItem::getOptions, PathItem::getPatch, PathItem::getPut);

    @Override
    public void customise(OpenAPI openApi) {
        openApi.getPaths().forEach((path, item) -> getOperations(item).forEach(operation -> {
            List<String> tags = operation.getTags();
            if (tags != null && tags.contains(UNSECURED)) {
                operation.setSecurity(Collections.emptyList());
                operation.setTags(filterTags(tags));
            }
        }));
    }

    private static Stream<Operation> getOperations(PathItem pathItem) {
        return OPERATION_GETTERS.stream()
                .map(getter -> getter.apply(pathItem))
                .filter(Objects::nonNull);
    }

    private static List<String> filterTags(List<String> tags) {
        return tags.stream()
                .filter(t -> !t.equals(UNSECURED))
                .collect(Collectors.toList());
    }
}

Now we can add @Tag(name = SecurityOverrideCustomizer.UNSECURED) to unsecured methods:

    @Tag(name = SecurityOverrideCustomizer.UNSECURED)
    @GetMapping("/open")
    @ResponseBody
    public String open() {
        return "It works!";
    }

Please bear in mind that it is just a workaround. Hopefully, the issue will be resolved in the next springdoc-openapi versions (at the time of writing it the current version is 1.2.18).

For a working example see springdoc-security-override-fix