{#JCV#}

JSON Content Validator (JCV) allows you to compare JSON contents with embedded validation.

Table of contents

• Summary
• Examples
• Quick start
  • Core module
  • AssertJ module
  • Hamcrest module
  • WireMock module
• Learn more

Summary

Make a full json content assertion using the minimum amount of code using an expected JSON content with the possibility to add custom field validation.

Make your tests light, easy to write, readable and exhaustive.

This tool is based on the very useful JSONassert one and add the embedded validation system to assert unpredicatable values.

Examples

The actual JSON you want to validate :

{
    "field_1": "some value",
    "field_2": "3716a0cf-850e-46c3-bd97-ac1f34437c43",
    "date": "2011-12-03T10:15:30Z",
    "other_fields": [{
        "id": "2",
        "link": "https://another.url.com/my-base-path/query?param1=true"
    }, {
        "id": "1",
        "link": "https://some.url.com"
    }]
}

The expected JSON with embedded validation :

{
   "field_1": "some value",
   "field_2": "{#uuid#}",
   "date": "{#date_time_format:iso_instant#}",
   "other_fields": [{
       "id": "1",
       "link": "{#url#}"
   }, {
       "id": "2",
       "link": "{#url_ending:query?param1=true#}"
   }]
}

More examples available here : ekino/jcv-examples

Quick start

Core module

JCV add a new JSONComparator implementation to make the possibility to use validators inside the expected JSON, so it requires the JSONassert dependency to work.

Dependencies

Maven

<dependencies>
  ...
  <dependency>
    <groupId>org.skyscreamer</groupId>
    <artifactId>jsonassert</artifactId>
    <version>1.5.3</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>com.ekino.oss.jcv</groupId>
    <artifactId>jcv-core</artifactId>
    <version>1.6.0-SNAPSHOT</version>
    <scope>test</scope>
  </dependency>
  ...
</dependencies>

Gradle

dependencies {
  ...
  testImplementation 'org.skyscreamer:jsonassert:1.5.3'
  testImplementation 'com.ekino.oss.jcv:jcv-core:1.6.0-SNAPSHOT'
  ...
}

Note:

Do not forget to add the maven snapshots repository for SNAPSHOT versions :

Maven

<repositories>
  ...
  <repository>
    <id>maven-snapshots</id>
    <url>http://oss.sonatype.org/content/repositories/snapshots</url>
    <layout>default</layout>
    <releases>
      <enabled>false</enabled>
    </releases>
    <snapshots>
      <enabled>true</enabled>
    </snapshots>
  </repository>
  ...
</repositories>

Gradle

repositories {
    maven {
        url = uri("https://oss.sonatype.org/content/repositories/snapshots/")
    }
}

AssertJ module

A JCV module that supports AssertJ.

Example

import static com.ekino.oss.jcv.assertion.assertj.JsonCompareAssert.*;

@Test
void testContainsValidator() throws JSONException {
    assertThatJson("{\"field_name\": \"hello world!\"}")
        .isValidAgainst("{\"field_name\": \"{#contains:llo wor#}\"}");
}

Dependencies

Maven

<dependencies>
  ...
  <dependency>
    <groupId>org.skyscreamer</groupId>
    <artifactId>jsonassert</artifactId>
    <version>1.5.3</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>org.assertj</groupId>
    <artifactId>assertj-core</artifactId>
    <version>3.26.3</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>com.ekino.oss.jcv</groupId>
    <artifactId>jcv-assertj</artifactId>
    <version>1.6.0-SNAPSHOT</version>
    <scope>test</scope>
  </dependency>
  ...
</dependencies>

Gradle

dependencies {
  ...
  testImplementation 'org.skyscreamer:jsonassert:1.5.3'
  testImplementation 'org.assertj:assertj-core:3.26.3'
  testImplementation 'com.ekino.oss.jcv:jcv-assertj:1.6.0-SNAPSHOT'
  ...
}

Hamcrest module

A JCV module that supports Hamcrest.

Example

import static com.ekino.oss.jcv.assertion.hamcrest.JsonMatchers.*;
import static org.hamcrest.MatcherAssert.*;

@Test
void testContainsValidator() throws JSONException {
    assertThat(
        "{\"field_name\": \"hello world!\"}",
        jsonMatcher("{\"field_name\": \"{#contains:llo wor#}\"}")
    );
}

Dependencies

Maven

<dependencies>
  ...
  <dependency>
    <groupId>org.skyscreamer</groupId>
    <artifactId>jsonassert</artifactId>
    <version>1.5.3</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>org.hamcrest</groupId>
    <artifactId>hamcrest</artifactId>
    <version>3.0</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>com.ekino.oss.jcv</groupId>
    <artifactId>jcv-hamcrest</artifactId>
    <version>1.6.0-SNAPSHOT</version>
    <scope>test</scope>
  </dependency>
  ...
</dependencies>

Gradle

dependencies {
  ...
  testImplementation 'org.skyscreamer:jsonassert:1.5.3'
  testImplementation 'org.hamcrest:hamcrest:3.0'
  testImplementation 'com.ekino.oss.jcv:jcv-hamcrest:1.6.0-SNAPSHOT'
  ...
}

WireMock module

A JCV module extension for WireMock.

Example

Register the extension on your WireMock server:

import com.github.tomakehurst.wiremock.WireMockServer
import com.github.tomakehurst.wiremock.core.WireMockConfiguration
import com.ekino.oss.jcv.assertion.wiremock.JcvRequestMatcherExtension

private val wireMockServer by lazy {
  WireMockServer(
    WireMockConfiguration()
      .dynamicPort()
      .extensions(JcvRequestMatcherExtension())
  )
}

Then you can stub via code:

import com.github.tomakehurst.wiremock.client.WireMock.aResponse
import com.github.tomakehurst.wiremock.client.WireMock.post
import com.github.tomakehurst.wiremock.client.WireMock.urlEqualTo
import com.ekino.oss.jcv.assertion.wiremock.JcvRequestMatcherExtension

wireMockServer.stubFor(
  post(urlEqualTo("/some_url"))
    .andMatching(
      JcvRequestMatcherExtension.toRequestMatcher(
        json =
        """
        {
          "some_field": "{#not_empty#}"
        }
        """
      )
    )
    .willReturn(
      aResponse()
        .withHeader("Content-Type", "text/plain")
        .withStatus(200)
        .withBody("OK")
    )
)

Or you can stub via mapping file:

{
  "request": {
    "method": "POST",
    "url": "/some_url",
    "customMatcher": {
      "name": "equalToJcv",
      "parameters": {
        "json": {
          "some_field": "{#not_empty#}"
        },
        "ignoreArrayOrder": true,
        "ignoreExtraElements": false
      }
    }
  },
  "response": {
    "status": 200,
    "body": "OK"
  }
}

Dependencies

Maven

<dependencies>
  ...
  <dependency>
    <groupId>org.skyscreamer</groupId>
    <artifactId>jsonassert</artifactId>
    <version>1.5.3</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>org.wiremock</groupId>
    <artifactId>wiremock</artifactId>
    <version>3.9.1</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>com.ekino.oss.jcv</groupId>
    <artifactId>jcv-wiremock</artifactId>
    <version>1.6.0-SNAPSHOT</version>
    <scope>test</scope>
  </dependency>
  ...
</dependencies>

Gradle

dependencies {
  ...
  testImplementation 'org.skyscreamer:jsonassert:1.5.3'
  testImplementation 'org.wiremock:wiremock:3.9.1'
  testImplementation 'com.ekino.oss.jcv:jcv-wiremock:1.6.0-SNAPSHOT'
  ...
}

Learn more

You will find more information (validators, guided tours...) in the Wiki.