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Disable Datasource Auto Configuration in Spring Boot

Today morning, We had an interesting situation. Our spring boot application which is configured to run on MySQL needs to be run on a system which does not have MySQL database installed. But we had to develop few UI modules alone. So we decided to go ahead but how do we disable MySQL database auto-configuration?

Here is what we did.

Spring Boot is an interesting framework that helps auto configure everything for you. In case you need to override any of the auto-configuration, all you need to do is to simply customize it. The auto-configuration backs away. In this typical scenario, we dont want to customize the auto-configuration, rather we want to disable it temporarily until we complete our UI modules. As soon as the system is ready or we find alternate systems, we can run the Application with full-blown schema.

OK. so how did we disable the database auto configuration?

We are using Spring Boot with JPA, Hibernate and FlywayDB migration tool. If this is going to be your boot applicatio…
Recent posts

Bean Validation (JSR 303) using Hibernate Validator in Spring Boot

Bean Validation
Bean validation has always been a tremendous effort in Java based Enterprise application development. Java Bean Validation (JSR 303) is the framework that defines how Java Beans should be validated. There are few validator APIs that support JSR 303. Hibernate validator is the most popular among them. It helps validate Java Beans using annotation and the beans can be validated at presentation layer, service and data access layer. Hibernate validator also offers custom validation, cross field validations. You can checkout the latest hibernate validator documentation for built-in validator annotations.

Assumption      : Spring Boot (1.5.6),  Hibernate Validator(5.4.1.Final), Maven Projects

Integrating Spring Boot & Hibernate Validator
Spring Boot offers built-in starter dependency management for most of the frameworks and APIs available in Java Application Development. It has support for bean validation using hibernate validator API. The discussion focuses on how to val…

Spring Boot, Thymeleaf static resource refresh

Introduction
Thymeleaf is a natural template engine that is often used in modern java-server-side applications that are running in web and standalone environments. Ease of natural templating gives the upperhand to pick Thymeleaf over other frameworks in Java Serverside application development. Spring provides support to thmyeleaf development. Spring boot has its own starter dependency for thymeleaf. While we develop thmyeleaf templates using spring boot applications, Front End Developers cannot see the changes that are made in the resources while the application is running. But the changes don't take effect in the browser until the application is reloaded or restarted.

Solution
We can solve this templating-resources-reloading without application restart. Spring boot uses properties in which we have to just disable the cache for Thymeleaf. Below are the steps to achieve these.

Step 1: Disable the cache by setting the spring.thymeleaf.cache = false in the application.properties file. 

In-Place editing with X-Editable using Datatable plugin

Introduction
In-place editing is a trending feature that can be seen in many latest web applications, a popular example would be trello.com where the editing data happens on the web page without any explicit forms or popups. Another such example I could point out is, thoughtplan.com. The in-place editing is very nice in such a way that editing data seems so natural and user friendly.

To enable in-place editing, there are many free JQuery plugins available on the internet. We are discussing a very popular plugin called x-editable. Most of the time we use html tables to display data where in-place editing is enabled. Hence we need another plugin to elegantly display tables with enormous data. We use a famous JQuery plugin called datatable. Both of these plugins are used widely and free to use.

Assumption      : Bootstrap 3, JQuery used Projects

Integration
In order to enable datatable features on any ordinary table found on web page, we should initialise datatable plugin for that table. I…

Flyway Integration with Spring Boot

This post talks about how we integrated Flyway with Spring Boot and enjoyed the power of database migration seamlessly. If you have worked on Enterprise applications, data migration is really liability for your project. One wrong move, your data get lost during your production patch fixes or release updates. To mitigate such issues happening over manual migrations or even in-house programmatic data migration, we adopted Flyway, an open-source database migration tool that favors simplicity and convention over configuration. Luckily, Spring Boot naturally gels with Flyway.

Flyway               : 4.2.0
Spring Boot      : 1.5.6.RELEASE
Assumption      : Java, MySQL & Maven Used Projects

Flyway Maven Dependency
Flyway has Maven dependency that we need to specify in the pom.xml while we configure spring-boot-starter dependencies. This makes sure Spring Boot look for database migration scripts in the classpath. The default lookout path is src/main/resources/db/migration and the scripts are …

CSRF enabled Ajax requests using Spring Security

Many of you who have worked on Spring Security might be aware of the fact that Spring Security protects applications from Cross Site Request Forgery using _csrf tokens in the request sent to the web server. You can find a detailed understanding in the Spring documentation page. The objective of this post is to explain how to send _csrf tokens in the Ajax requests when we protect our application URL and application access using spring security.

How to get CSRF tokens
While we submit a form using an application that is protected with Spring Security, the form gets a default hidden parameter in the form body when using <form:form> element. The param contains the _csrf tokens to authenticate the requests in the server. In case we use other ways to create forms, we have to manually include a hidden parameter that contains name as ${_csrf.parameterName} and  value as ${_csrf.token}. For example,
<inputtype="hidden"name="${_csrf.parameterName}"value="${_csrf…

Thymeleaf th:remove vs th:if Processors

Interestingly Makinus team encountered a scenario where the team has to choose between th:remove and th:if processors. The situation is like this. Makinus team worked on a project and the team lead suggested to go with #Thymeleaf template instead of decades old JSP. Hence it adopted Thymeleaf and Thymelead Layout framework to do layout-ing.

Thymeleaf Layout
Thymeleaf layout is a framework that helps doing the layout work just as tiles framework does it using JSP technology. The framework has 5 processors, important of which is layout:decorate. The processor layout:decorate works in the layout-content template model where the content template is a small piece of template that replaces content part of the layout template. This works as if parent/child templating mode where parent will define layout format while the child template replaces only the specified content portions.

Head Element Merging Strategy
Thymeleaf layout uses a special strategy to merge parent and child template <head…