Spring PetClinic Sample Application - Instrumented
Why this fork?
- The goal of this fork is to demonstrate how to instrument an application using aspect-oriented programming techniques in concert with logging context and output patterns.
- The Spring PetClinic is the de-facto reference application for Spring, and I am just taking advantage of it being in a build-able, runnable state.
- Hopefully this "makeover" shows how you can quickly create highly instrumented applications without interfering (much) with your existing codebase
What is different?
- A new Aspect was introduced which provided time tracing for certain classes and methods
- This Aspect takes advantage of the object proxy the Spring DI container provides, to perform "before and after" logic that is then logged.
- A new attribute (@Instrumentable) was introduced as a Marker to indicate what classes and/or methods were to be instrumented.
- A new interceptor was introduced to set vital context based on incoming Web requests.
Logging and MDC
- System.out calls were replaced with proper logging (SLF4J + Logback) calls.
- Log Patterns were introduced in the log configuration
- Mapped Diagnostic Context (MDC) was leveraged to set context when required (see Interceptors) and write context with all subsequent downstream calls.
- A simple Spring Security integration was created in order to demonstrate the utility of having the Principal in the log context
Understanding the Spring Petclinic application with a few diagrams
Running petclinic locally
git clone https://github.com/SpringSource/spring-petclinic.git mvn tomcat7:run
You can then access petclinic here: http://localhost:9966/petclinic/
In case you find a bug/suggested improvement for Spring Petclinic
Our issue tracker is available here: https://github.com/SpringSource/spring-petclinic/issues
Working with Petclinic in Eclipse/STS
The following items should be installed in your system:
- Maven 3 (http://www.sonatype.com/books/mvnref-book/reference/installation.html)
- git command line tool (https://help.github.com/articles/set-up-git)
- Eclipse with the m2e plugin (m2e is installed by default when using the STS (http://www.springsource.org/sts) distribution of Eclipse)
Note: when m2e is available, there is an m2 icon in Help -> About dialog. If m2e is not there, just follow the install process here: http://eclipse.org/m2e/download/
- In the command line
git clone https://github.com/SpringSource/spring-petclinic.git
- Inside Eclipse
File -> Import -> Maven -> Existing Maven project
Looking for something in particular?
|Inside the 'Web' layer||Files|
|Spring MVC- Atom integration||VetsAtomView.java mvc-view-config.xml|
|Spring MVC - XML integration||mvc-view-config.xml|
|Spring MVC - ContentNegotiatingViewResolver||mvc-view-config.xml|
|Spring MVC Test Framework||VisitsViewTest.java|
|JSP custom tags||WEB-INF/tags createOrUpdateOwnerForm.jsp|
webjars declaration inside pom.xml
Resource mapping in Spring configuration
sample usage in JSP
|Dandelion-datatables||ownersList.jsp vetList.jsp web.xml|
|Thymeleaf branch||See here|
|Branch using GemFire and Spring Data GemFire instead of ehcache (thanks Bijoy Choudhury)||See here|
|'Service' and 'Repository' layers||Files|
|Bean Profiles||business-config.xml ClinicServiceJdbcTests.java web.xml|
|JdbcTemplate||business-config.xml jdbc folder|
|JPA||business-config.xml jpa folder|
|Spring Data JPA||business-config.xml springdatajpa folder|
|Gradle branch||See here|
Interaction with other open source projects
One of the best parts about working on the Spring Petclinic application is that we have the opportunity to work in direct contact with many Open Source projects. We found some bugs/suggested improvements on various topics such as Spring, Spring Data, Bean Validation and even Eclipse! In many cases, they've been fixed/implemented in just a few days. Here is a list of them:
|Spring JDBC: simplify usage of NamedParameterJdbcTemplate||SPR-10256 and SPR-10257|
|Bean Validation / Hibernate Validator: simplify Maven dependencies and backward compatibility||HV-790 and HV-792|
|Spring Data: provide more flexibility when working with JPQL queries||DATAJPA-292|
|Eclipse: validation bug when working with .tag/.tagx files||STS-3294|