Spike: Figure out how to plug JSON schema in from external library (jar file) into a module

Owned by Natalia Zaitseva
Last updated: Aug 13, 2019Version comment
5 min read

  MODUSERS-140 - Getting issue details... STATUS

Description:

There is a need to use external JSON schema(s) to describe data in RAML API interfaces. 
The schema is expected to reside inside a jar file which attached to a module as a regular dependency.
If the above is not achievable – propose any options of how external schemas can be used in a module with minimal effort


Input values:

assume existing RAML directory structure:

\ramls
-\examples
-\raml-util
-library.raml
-nataliabook.json
-bookCollection.json

where bookCollection.json file contains a reference to the single item 

as following:

  "$ref": "nataliaBook.json"

Results:

   1. Include JSON schemas as a dependency to the module using maven plugins

Approach:

  • add a dependency to the target module
  • include following plugins to the .pom file
    •  Add a plugin to unpack RAML and JSON files 

      This plugin unpack the files of particular dependency

      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <version>3.1.0</version>
        <executions>
          <execution>
            <id>unpack</id>
            <phase>prepare-package</phase>
            <goals>
              <goal>unpack</goal>
            </goals>
            <configuration>
              <artifactItems>
                <artifactItem>
                  <groupId>org.folio</groupId>
                  <artifactId>mod-data-upload</artifactId>
                  <outputDirectory>${ramlfiles_path}</outputDirectory>
                  <overWrite>true</overWrite>
                  <includes>ramls/</includes>
                  <excludes>ramls/raml-util/, ramls/*.list</excludes>
                </artifactItem>
              </artifactItems>
              <overWriteReleases>false</overWriteReleases>
              <overWriteSnapshots>true</overWriteSnapshots>
            </configuration>
          </execution>
        </executions>
      </plugin>
    •  Сlean up the folder

      the following property seems not working for the maven-dependency-plugin

      <overWrite>true</overWrite>

      this means that every time you need to build the project you have to remove the folder manually.

      To simply this process add the maven-clean-plugin to do it automatically by specifying the folder

      <plugin>
        <artifactId>maven-clean-plugin</artifactId>
        <version>3.1.0</version>
        <configuration>
          <filesets>
            <fileset>
              <directory>ramls/ramls</directory>
              <followSymlinks>false</followSymlinks>
            </fileset>
          </filesets>
        </configuration>
      </plugin>
    •  Add the ant-run plugin

      After the module builds, all references to files will point to exact files in the current system:

      which is not convenient to use in case of the different build environments.

      The following plugin task will replace found lines, specifying the path to file and cut it to leave only the file name.

      <plugin>
        <artifactId>maven-antrun-plugin</artifactId>
        <version>1.8</version>
        <executions>
          <execution>
            <phase>prepare-package</phase>
            <goals>
              <goal>run</goal>
            </goals>
            <configuration>
              <tasks>
                <replaceregexp match="(file:.*[/])" replace="" byline="true">
                  <fileset dir="${ramlfiles_path}/ramls" includes="**/*.json" />
                </replaceregexp>
              </tasks>
            </configuration>
          </execution>
        </executions>
      </plugin>

Advantages: 

  • No need to modify RMB module 

Disadvantages:

  • Insert a bunch of plugins to every module needed
  • maintain regex in case of change

      2. Add plugin to RMB to manage references 

Approach:

Advantages: 

  • Changes done in RMB will apply to all modules, which are used it  

Disadvantages:

  • Need to modify RMB module 
  • Need to investigate the amount of changes to RMB

     3. Add schemas to RAML module 

Approach:

Advantages: 

  • All needed files stored in one place and modules can access it as other schemas already stored in RAML module

Disadvantages:

  • Raml module will store additional files, which probably not all of the modules are interested in.

Useful links:

  • Maven-Antrun-Plugin
  • Maven-Dependency-Plugin: Unpack

  • Maven jsonschema2pojo plugin and 

     Sample example of plugin 
    <plugin>
    <groupId>org.jsonschema2pojo</groupId>
    <artifactId>jsonschema2pojo-maven-plugin</artifactId>
    <version>0.5.1</version>
    <configuration>
        <skip>false</skip>
        <sourceDirectory>${basedir}/src/main/resources/schema/json/modules/</sourceDirectory>
        <outputDirectory>${basedir}/src/gen/java/json</outputDirectory>
        <removeOldOutput>true</removeOldOutput>
        <annotationStyle>none</annotationStyle>
        <includeGetters>true</includeGetters>
        <includeSetters>true</includeSetters>
        <useCommonsLang3>true</useCommonsLang3>
        <useLongIntegers>true</useLongIntegers>
        <includeJsr303Annotations>true</includeJsr303Annotations>
        <includeAdditionalProperties>false</includeAdditionalProperties>
        <includeHashcodeAndEquals>false</includeHashcodeAndEquals>
        <dateTimeType>java.time.LocalDateTime</dateTimeType>
        <targetPackage>com.all.my.modules</targetPackage>
    </configuration>
    <executions>
       <execution>
            <phase>process-resources</phase>
            <goals>
               <goal>generate</goal>
            </goals>
       </execution>
    </executions>
</plugin>