Dockerized Spring Boot Integration Test in Mono Repo

Alican Akkuş bio photo By Alican Akkuş Comment

Hi, in this article we will talk about the dockerized integration test in the mono repo.

As you know there are many different tests we write such as unit, integration, functional, feature, contract, system etc. Integration tests are one of them. Their differences are not related to this article.

At first glance, integration tests are expensive. Because of needed to set up many resources during tests. Sometimes you need to up the database, messaging queue, cache provider and etc. In our example, we will use the only database. We believe that the in-memory database is not reliable because of is not like a real system. We use MySQL in production but tests are running on H2 or any other in-memory databases. We can not be sure that our code runs correctly in the real system. Therefore we will use the real database in the test. For example DATEADD(hour, 1, now() is a valid syntax for H2 but the invalid syntax for MySQL, correct syntax should be DATE_ADD(now(), INTERVAL 1 HOUR). Do you still trust to the in-memory databases?

Also, we don’t want to use any tool such as TestContainer in the source code. Test source code should not create or configure infrastructure, should focus to only own test, not infra! We will use dockerized MySQL during tests.

Let’s begin;

We will use Gradle as the build tool.

In the mono repo, we have many projects/microservices. All project has an integrationTest task for integration tests. We’ve also it task for the run all of them.

When you run the integration tests, the first step is the start database in our example. Run all test after database up and running. After tests completed down the database and clean up the resource.

We’ve multiple microservice in the mono repo. All microservice creating own database/schema during the test. Each microservice independent of others.


test {
    failFast true
    testLogging {
        events "PASSED", "STARTED", "FAILED", "SKIPPED"
    afterSuite { desc, result ->
        if (!desc.parent) {
            println "\nTest result: ${result.resultType}"
            println "Test summary: ${result.testCount} tests, " +
                    "${result.successfulTestCount} succeeded, " +
                    "${result.failedTestCount} failed, " +
                    "${result.skippedTestCount} skipped"
    useJUnitPlatform {
        includeEngines 'junit-jupiter'
        excludeTags 'integrationTest'

task integrationTest(type: Test) {
    testLogging {
        events "PASSED", "STARTED", "FAILED", "SKIPPED"
    useJUnitPlatform {
        includeTags 'integrationTest'

All microservices have an ‘integrationTest’ task as mentioned above. Marks all integration test as integrationTest with JUnit 5 @Tag annotation. And we also have ‘it’ task as mentioned before.

All projects include testing.gradle file to their configuration. Add below configuration to root build.gradle;

allprojects {
 apply from: “$rootProject.projectDir/config/testing.gradle”


task dbup(type: Exec) {
    workingDir rootProject.projectDir
    commandLine 'sh', '-c', './scripts/ db up'

task dbdown(type: Exec) {
    workingDir rootProject.projectDir
    commandLine 'sh', '-c', './scripts/ db down'

task it() {
    doFirst {
        println 'Integration tests are going to run...'

    //run db
    dependsOn dbup

    //run all integration tests

    //stop db
    finalizedBy dbdown

    doLast {
        println 'Integration test are completed.'

Let see it task. It’s run database and run all integration tests in the mono repo and finalized task by database down command.

Let’s look at the script for up and down database. It’s very simple as below;

#!/usr/bin/env bash

run_db() {
    docker run --name test_db --env MYSQL_ROOT_PASSWORD=root_password -p 4306:3306 -d mysql

down_db() {
    docker rm -f test_db

case "${1}" in
        case "${2}" in
        "up") echo Starting db && run_db;;
        "down") echo Stopping db && down_db;;
        echo Unknown command! ${1}

Finally, test property file looks like below for spring boot application;

    name: my-api
    active: test

  profiles: test
    show-sql: false
      ddl-auto: create-drop
    open-in-view: false
    database-platform: org.hibernate.dialect.MySQLDialect
    url: jdbc:mysql://localhost:4306/my-api?createDatabaseIfNotExist=true
    driver-class-name: com.mysql.jdbc.Driver
    username: root
    password: root_password

Run gradle it task via ‘gradle it’ command. The output looks like below;

> Task :dbup
    Starting db
> Task :it
    Integration tests are going to run…
    ….some tests are running
    ….some tests are running
    Integration test are completed.
> Task :dbdown
    Stopping db
    BUILD SUCCESSFUL in 1m 34s
    35 actionable tasks: 20 executed, 15 up-to-date
➜ mono-repo (master) ✔

The database is a sample for integration tests. You can create any other resources for the test are needed.


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