Why does springfox-swagger2 UI tell me "Unable to infer base url."

Question

Why does springfox-swagger2 UI tell me Unable to infer base url. As far as I know, I am using a typical Swagger spring-boot configuration.

As you can see in the screenshot, the swagger-fox url backing the UI is example.com/api . NOTE: I get a standard Spring Whitelabel Error Page when I navigate to: https://localhost:9600/api/v2/api-docs/ . I suspect this is the root of the problem? I see no errors that Spring didn't load springfox-swagger2 and so I don't know why that isn't working.

My config looks something like this (and I have tried all sorts of variations of this config, from searching the net for advice):

@EnableSwagger2
@EnableWebMvc
@ComponentScan(basePackages = {"com.company.project"})
public class SwaggerConfig
{
    @Bean
    public Docket api() {
        return new Docket(DocumentationType.SWAGGER_2)
                .select()
                .apis(Predicates.not(RequestHandlerSelectors.basePackage("org.springframework.boot")))
                .apis(Predicates.not(RequestHandlerSelectors.basePackage("org.springframework.cloud")))
                .apis(Predicates.not(RequestHandlerSelectors.basePackage("org.springframework.data.rest.webmvc")))
                .paths(PathSelectors.any())
                .build();
    }
}

And

<!-- to generate /swagger-ui.html -->
<dependency>
    <groupId>io.springfox</groupId>
    <artifactId>springfox-swagger2</artifactId>
    <version>2.7.0</version>
</dependency>

<dependency>
    <groupId>io.springfox</groupId>
    <artifactId>springfox-swagger-ui</artifactId>
    <version>2.7.0</version>
</dependency>

NOTE: Interestingly, when I try version 2.6.0, I don't get the modal popup but my Swagger UI shows 0 api content. So, i know that modal must be fairly new?

If there is not enough info here, leave me a comment.

Lyn

Put a breakpoint at springfox.documentation.swagger2.web.Swagger2Controller#getDocumentation and debug to find out why you are getting an error while trying to access https://localhost:9600/api/v2/api-docs/ – Shopkeeper

check your versions of springfox-swagger2 and springfox-swagger-ui. both versions should be same. I had this problem due to different versions – Equi

Answer 1

It turns out that the solution to my problem was to move the @EnableSwagger2 annotation into the main Configuration class, along with the Docket Bean.

I had created a separate class in a sub-package with the Docket Bean and I was expecting it to get scanned by Spring and load the bean. Perhaps I failed to annotate that docket class with @Component, or maybe the the problem was something else, but I got it working.

Lyn

for me worked adding @ComponentScan to my SwaggerConfig class – Cabinetmaker

Worked out for me adding @EnableSwagger2 annotation for my main config class. This actually happened for me in spring boot webapp. – Acidify

Answer 2

I was able to resolve the issue by adding SpringBootApplication with annotation - as suggested by Mark :

@EnableSwagger2

Faubion

I don't know how I missed to add it. after spending so much of time. it worked like a charm !!. – Polythene

I had this annotation in the SwaggerConfig class but the "Unable to infer base URL" error persisted. When I moved this annotation to my @SpringBootApplication class, the problem went away. – Danndanna

Does this still work with springfox swagger 3.0.0? I have the exact same issue and this fix did not do anything. – Chammy

Answer 3

For me the problem was that Spring Security was not allowing access to some resources needed by swagger-ui. The solution was to allow anonymous access to the following paths:

• /swagger-ui.html
• /webjars/**
• /v2/**
• /swagger-resources/**

In my case it is fine that these resources can be accessed without authentication.

Parboil

how to add this – Ganny

@Ganny : @Override public void configure(WebSecurity web) throws Exception {web.ignoring().mvcMatchers("/swagger-ui.html/**", "/configuration/**","/swagger-resources/**", "/v2/api-docs","/webjars/**");} – Reggy

I am not using Spring Security, same problem. – Coeternal

If 'not allowing anonymous' were the issue, seems like the error would different, like a permissions type of error. – Lyn

Was the exact issue I had with Spring Security. Just add .antMatchers("/swagger-ui/*", "/swagger-ui.html", "/webjars/**", "/v2/**", "/swagger-resources/**").permitAll() to the WebSecurityConfiguration.configure HttpSecurity function, amongst the rest of your code within – Dionne

Answer 4

Add @EnableSwagger2 annotation in the main file of Springboot application

@SpringBootApplication
@EnableSwagger2
public class SampleApplication {

    public static void main(String[] args) {
        SpringApplication.run(SampleApplication.class, args);
    }

}

Headliner

Yes, I believe this is the simplest resolution although there are other interesting ideas in this thread. – Lyn

Answer 5

in my case i had this line in my WebSecurityConfig.java:

.antMatchers("swagger-ui.html").permitAll()

and when i added this one:

.antMatchers("/swagger-resources/**").permitAll()

my problem resolved.

Weitzel

Answer 6

This has worked for me.

@Override
    public void configure(WebSecurity web) throws Exception {
         web
        .ignoring()
        .antMatchers(
                "/swagger-resources/**",
                "/swagger-ui.html",
                "/v2/api-docs",
                "/webjars/**");
    }

Make sure about the root path.

Patricio

Answer 7

Just Extend your main class with SpringBootServletInitalizer. It Will Work fine. Take reference as bellow.

public class TestApp extends SpringBootServletInitializer{

    public static void main(String[] args) {

       SpringApplication.run(TestApp.class, args);
   }
}

Malta

... or mark spring-boot application with annotation: @EnableSwagger2 – Dory

Answer 8

For Spring 2 use @SpringBootApplication annotation and extends your class application from SpringBootServletInitializer then override the method SpringApplicationBuilder

@SpringBootApplication
public class TestApp extends SpringBootServletInitializer{

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(TestApp.class);
    }


    public static void main(String[] args) {
        SpringApplication.run(TestApp.class, args);
    }
}

Samellasameness

Answer 9

I am using spring boot.

In my case I made mistake in package name. in my project the base package name is

org.liferayasif.documents

so my configuration file should be inside

org.liferayasif.documents.config

config -> u can give any name.

but by mistake I put in different package name give below

org.liferayasif.config

once I put the configuration file inside proper package name in my case

org.liferayasif.documents.config

then it worked properly.

Hymanhymen

This is because Spring scans the classpath and part of what Spring scans by default is either a 'config' folder in classpath root or a 'config' package. This makes sense. Whatever you do to fix this problem, just make sure Spring scanning picks up the swagger bean. I personally wouldn't solve it this way since people who don't understand the 'config' folder scanning will not truly understand your code. – Lyn

Answer 10

It's 2024 and I ran into this problem still. I tried reading all the internet but hit a lot of dead ends until I actually bumped into a solution that works. Apparently, Spring Boot 3 needs a different library than Spring Boot 2 to be able to use Swagger 3. Let’s set it up in a new project and see how to use the most basic features.The solution was to add this dependency into the pom.xml file and boom, it worked.

<dependency>
   <groupId>org.springdoc</groupId>
   <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
   <version>2.0.2</version>
</dependency>

You can refer to the full article here.

Vories

Answer 11

In my case I am deploying our springboot(2.1.2) with swagger2(2.9.2) application as war file in tomcat8.5 and getting the same error.

Later I was able to fix just by extending this class file AppConfig extends SpringBootServletInitializer

My complete AppConfig file

package org.mydomain

import java.net.URL;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.domain.EntityScan;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.scheduling.annotation.EnableScheduling;

import springfox.documentation.swagger2.annotations.EnableSwagger2;

@SpringBootApplication(scanBasePackages = "org.mydomain")
@EntityScan({"org.mydomain.entity"})
@EnableJpaRepositories({"org.mydomain.repository"})
@EnableSwagger2
@EnableScheduling
public class AppConfig extends SpringBootServletInitializer {

  // We can optionally have spring boot way of starting main method
  public static void main(String[] args) {
     SpringApplication.run(AppConfig.class, args);
  }
}

This is the blog I referred how to deploy springboot application into tomcat

Note: I have not configured swagger docket just used the default implementation.

Rudman

Answer 12

I needed to add anonymous access to resources in Spring Security method: protected void configure(HttpSecurity http)

.antMatchers("/api/**", "/swagger-ui.html", "/webjars/**", "/v2/**", "/swagger-resources/**").anonymous()

And then it starts working.

Hedve

Answer 13

OAHH, for me it was something new. I had 2 different versions for springfox-swagger2 and springfox-swagger-ui

Before:

    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-swagger2</artifactId>
        **<version>2.6.1</version>**
        <scope>compile</scope>
    </dependency>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-swagger-ui</artifactId>
        **<version>2.9.2</version>**
    </dependency>

After:

    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-swagger2</artifactId>
        **<version>2.9.2</version>**
        <scope>compile</scope>
    </dependency>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-swagger-ui</artifactId>
        **<version>2.9.2</version>**
    </dependency>

This solved my problem.

Equi

Answer 14

I had the same issue, but (maybe) I had a version missmatch in the pom.xml

My project version is:

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.2.0.M5</version>
    <relativePath /> <!-- lookup parent from repository -->
</parent>

Then, It started to work when I added the following dependency:

  <dependency>
        <groupId>org.springframework.plugin</groupId>
        <artifactId>spring-plugin-core</artifactId>
        <version>1.2.0.RELEASE</version>
    </dependency>

Found at: https://github.com/springfox/springfox/issues/2932

Folderol

Answer 15

this page localhost:9000/sawgger-ui with needs other external resources like swagger-ressources /v2/api-docs ... this resources is denyed so you mustto permit them or ignoring them

inspect your page to see it witch ressource needs to igniore or permit

Gennagennaro

Answer 16

I haved same issue and spend few hours to resolved:

I use springfox version 3.0.0

    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-boot-starter</artifactId>
        <version>3.0.0</version>
    </dependency>

with springboot 2.3.10:

   <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.3.10.RELEASE</version>

and spring security.

In my case I added paths to permitAll section in spring security configuration

 .antMatchers("  "/swagger-resources/**",
                    "/swagger-ui.html",
                    "/v2/api-docs",
                    "/webjars/**" ,
                    "/swagger-ui/**")
                .permitAll()

Substratosphere

Answer 17

With this annotation it works for newer versions:

spring.mvc.pathmatch.matching-strategy=ant-path-matcher

Via

Answer 18

pay attention if you're using SPRING BOOT 3 you have to add dependency of springdoc-openapi-starter-webmvc-ui

<dependency>
  <groupId>org.springdoc</groupId>
  <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
  <version>2.0.3</version>
</dependency>

Ballew

Answer 19

maybe you can try this one, it's better to use swagger version below 2.7.0. I found that Springboot Application need annotaion @EnableSwagger2 .

    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-swagger2</artifactId>
        <version>2.6.1</version>
    </dependency>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-swagger-ui</artifactId>
        <version>2.6.1</version>
    </dependency>

Im

Answer 20

Check you Java Version first, it seems to not work with Version Java 11, try using Java 8 seems to be fine

Playpen

have you try Java 1.2 ? – Mcghee