Postgres

In the previous step, we have switched to Oracle database from Mysql and in this step, we are going to switch from MySql to Postgres to further demonstrate how to config different database without change the service code. The only thing that needs to update is the configuration service.yml and pom.xml to include Postgres DB driver as part of the dependency.

The first step is to start the Postgres database in docker. The command has shown in previous step start databases

To switch to Postgres database, you need to replace service.yml from dbscript/postgres/config folder. First, let’s create a new folder from updates and copy the service.yml

cd ~/networknt/light-example-4j/rest/openapi/database
cp -r updates postgres
cp dbscript/postgres/config/service.yml postgres/src/main/resources/config

Second, let’s add Postgres DB driver to the pom.xml

In the properties section, add the following line.

        <version.postgres>42.1.1</version.postgres>        

In the dependencies section, add the following lines.

        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <version>${version.postgres}</version>
        </dependency>

Now let’s build the server from postgres folder.

cd postgres
mvn clean install exec:exec

Now you can test the server with curl to verify that the server is working with Postgres database.

curl -k https://localhost:8443/v1/query