Spring Security with Maven

1. Overview

This article will explain how to setup Spring Security with Maven and will go over specific use-cases of using Spring Security dependencies. The latest Spring Security releases can be found on Maven Central.

This is a followup to the previous Spring with Maven article, so for non-security Spring dependencies, that’s the place to start.

2. Spring Security with Maven

2.1. spring-security-core

The Core Spring Security support – spring-security-core – contains authentication and access control functionality, and has support for standalone (non-web) applications, method level security and JDBC:

<properties>
    <org.springframework.security.version>3.2.3.RELEASE</org.springframework.security.version>
    <org.springframework.version>4.0.4.RELEASE</org.springframework.version>
</properties>
<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-core</artifactId>
    <version>${org.springframework.security.version}</version>
</dependency>

Notice that we’re using the 3.2.x.RELEASE version of Spring Security – Spring and Spring Security are on different release schedules, so there isn’t a 1:1 match between the version numbers.

If you’re working with older versions of Spring – also very important to understand is the fact that, unintuitively, Spring Security 3.1.x do not depend on Spring 3.1.x releases! This is because Spring Security 3.1.x was released before Spring 3.1. The plan is to align these dependencies more closely in future releases – see this JIRA for more details – but for the time being, this has practical implications that we will look at next.

2.2. spring-security-web

To add Web support for Spring Security, the spring-security-web dependency is required:

<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-web</artifactId>
    <version>${org.springframework.security.version}</version>
</dependency>

This contains filters and related web security infrastructure enabling URL access control in a Servlet environment.

2.3. Spring Security and older Spring Core dependencies problem

This new dependency also exhibits a problem for the Maven dependency graph – as mentioned above, Spring Security jars do not depend on the latest Spring core jars (but on the previous version). This may lead to these older dependencies making their way on top the classpath instead of the newer 4.x Spring artifacts.

To understand why this is happening, we need to look at how Maven resolves conficts – in case of a version conflict, Maven will pick the jar that is closest to the root of the tree. In our case, spring-core is defined by both spring-orm (with the 4.x.RELEASE version) but also by spring-security-core (with the old 3.2.8.RELEASE version) – so in both cases, spring-jdbc is defined at a depth of 1 from the root pom of our project. Because of that, it will actually matter in which order spring-orm and spring-security-core are defined in our own pom – the first one will take priority so we may end up with either version on our classpath.

To address this problem, we will have to explicitly define some of the Spring dependencies in our own pom and not rely on the implicit Maven dependency resolution mechanism – doing this will put that particular dependency at depth 0 from our pom (as it’s defined in the pom itself) so it will take priority. All of the following fall into the same category and all need to be explicitly defined, either directly or, for multi-module projects, in the dependencyManagement element of the parent:

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-core</artifactId>
    <version>${org.springframework.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>${org.springframework.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jdbc</artifactId>
    <version>${org.springframework.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-beans</artifactId>
    <version>${org.springframework.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-aop</artifactId>
    <version>${org.springframework.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-tx</artifactId>
    <version>${org.springframework.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-expression</artifactId>
    <version>${org.springframework.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>${org.springframework.version}</version>
</dependency>

2.4. spring-security-config and others

To use the rich Spring Security XML namespace, the spring-security-config dependency will be required:

<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-config</artifactId>
    <version>${org.springframework.security.version}</version>
    <scope>runtime</scope>
</dependency>

No application code should compile against this dependency, so it should be scoped as runtime.

Finally, LDAP, ACL, CAS and OpenID support have their own dependencies in Spring Security: spring-security-ldap, spring-security-acl, spring-security-cas and spring-security-openid.

3. Using Snapshots and Milestones

Spring Security milestones as well as snapshots are available in the custom Maven repositories provided by Spring – for additional details about how to configure these, see how to use Snapshots and Milestones.

4. Conclusion

This article discusses the practical details of using Spring Security with Maven. The Maven dependencies presented here are of course some of the major ones, and there are several others that may be worth mentioning and have not yet made the cut. Nevertheless this should be a good starting point for using Spring in a Maven enabled project.

I usually post about Security on Google+ - you can follow me there:

Get My 3 Spring eBooks
There’s no “one single way” to build an app. This is one way that I found works well.
×
Build Your Web App with Spring (and quickly prototype it to 90%)

, ,

  • mohsin husen

    Really helpful article…

    i am currently doing the same !

    but the problem i am facing is i just want to upgrade the Spring version not the Spring Security version.

    Spring Version upgrade from 3.0.5 to 3.2.2

    Spring Security version : 2.0.3

    Is it possible ? ( assuming answer will be yes as it should be backward compatible ! )

    • baeldung

      Not sure if Spring 3.2.x is really compatible with such an old version of Spring Security (2.0.x) – the way I would go about it is use Eclipse Maven pom editor (see the Dependency Hierarchy tab) – to really pin down your versions and make sure that all Spring versions are correctly set to 3.2.x and all Spring Security versions to 2.0.x. Hope that helps.

      Eugen.

  • Justin Robbins

    Rather than ‘explicitly define some of the Spring dependencies’, couldn’t you have added them as exclusions to the Spring Security dependency?

    BTW: Great job with all the recent blog updates

    • Justin Robbins

      ah forget it, then you’d end up having to add the exclusions for each Spring Security dependency.

    • baeldung

      Sure, that’s also an option – the downside is that you’d have to add them as exclusions to each spring-security dependency in turn, whereas fixing the actual versions you want is only done once. There are two JIRAs scheduled to address this problem, but until these get done, I think this makes more sense:
      http://jira.codehaus.org/browse/MNG-3196
      http://jira.codehaus.org/browse/MNG-1977
      Thanks.
      Eugen.