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

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

@EnableSwagger2

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.

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.

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);
    }

}

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.

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);
    }
}

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.

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.

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.

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.

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.

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

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

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