How do I tell swagger-codgen about my custom generator?

Question

I am trying to make a custom swagger code generator based off of the existing JAX-RS generator. I followed the directions on the Swagger-Codegen GitHub page and generated a module using the command java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar meta -o output/myLibrary -n ABCCodegen -p com.abc.codegen. I created the templates that I will need and updated the AbcCodegenGenerator.java file.

I am running into problems when I try to run the code. The command java -cp swagger-codegen-cli.jar:ABCCodegen-swagger-codegen-1.0.0.jar io.swagger.codegen.Codegen -l ABCCodegen -o ./test gives me the error Could not find or load main class io.swagger.codegen.Codegen. After looking at the posts on the Swagger Google Group, I tried running the command java -cp ABCCodegen-swagger-codegen-1.0.0.jar -jar swagger-codegen-cli.jar langs. However, my custom module, abc, is not showing up in the list. Is there something I need to do programmatically in the java class itself to tell codegen about my generator?

Here is my class AbcCodegenGenerator.java:

package com.abc.codegen;



import io.swagger.codegen.*;
import io.swagger.models.Operation;
import io.swagger.codegen.languages.*;

import java.util.*;
import java.io.File;



public class AbcCodegenGenerator extends AbstractJavaJAXRSServerCodegen {
 public AbcCodegenGenerator(){
  super();

  sourceFolder = "src/main/java";
        invokerPackage = "io.swagger.api";
        artifactId = "com.abc";
        outputFolder = "generated-code/ABCCodegen";

        modelTemplateFiles.put("model.mustache", ".java"); 

        //Classes for the API
        apiTemplateFiles.put("api.mustache", ".java");
        apiTemplateFiles.put("apiService.mustache", ".java");
        apiTemplateFiles.put("apiServiceImpl.mustache", ".java");
        apiTemplateFiles.put("apiServiceFactory.mustache", ".java");
        apiPackage = "io.swagger.api";

        additionalProperties.put("title", title);

        //The location templates will be read from
        templateDir = "src/main/resources/ABCCodegen";



        //Adds ABCCodegen to the CliOptions list??
        CliOption library = new CliOption(CodegenConstants.LIBRARY, "library template (sub-template) to use");
        library.setDefault(DEFAULT_LIBRARY);

        Map<String, String> supportedLibraries = new LinkedHashMap<String, String>();
        supportedLibraries.put(DEFAULT_LIBRARY, "abc");
        library.setEnum(supportedLibraries);

        cliOptions.add(library);
        cliOptions.add(new CliOption(CodegenConstants.IMPL_FOLDER, CodegenConstants.IMPL_FOLDER_DESC));
        cliOptions.add(new CliOption("title", "a title describing the application"));
 }

 @Override
    public String getName()
    {
        return "abc"; 
    }

    @Override
    public String getHelp()
    {
        return "Generates a ABC Server application based on Jersey framework.";
    }

    @Override
    public void postProcessModelProperty(CodegenModel model, CodegenProperty property) {
        super.postProcessModelProperty(model, property);
        if("null".equals(property.example)) {
            property.example = null;
        }
    }

    @Override
    public void processOpts() {
        super.processOpts();

        if ( additionalProperties.containsKey(CodegenConstants.IMPL_FOLDER) ) {
            implFolder = (String) additionalProperties.get(CodegenConstants.IMPL_FOLDER);
        }

        supportingFiles.clear();
        writeOptional(outputFolder, new SupportingFile("pom.mustache", "", "pom.xml"));
        writeOptional(outputFolder, new SupportingFile("README.mustache", "", "README.md"));
        supportingFiles.add(new SupportingFile("ApiException.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "ApiException.java"));
        supportingFiles.add(new SupportingFile("ApiOriginFilter.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "ApiOriginFilter.java"));
        supportingFiles.add(new SupportingFile("ApiResponseMessage.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "ApiResponseMessage.java"));
        supportingFiles.add(new SupportingFile("NotFoundException.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "NotFoundException.java"));
        supportingFiles.add(new SupportingFile("jacksonJsonProvider.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "JacksonJsonProvider.java"));
        supportingFiles.add(new SupportingFile("BadRequestException.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "BadRequestException.java"));
        supportingFiles.add(new SupportingFile("JavaRestResourceUtil.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "JavaRestResourceUtil.java"));

        writeOptional(outputFolder, new SupportingFile("bootstrap.mustache", (implFolder + '/' + apiPackage).replace(".", "/"), "Bootstrap.java"));

        writeOptional(outputFolder, new SupportingFile("web.mustache", ("src/main/webapp/WEB-INF"), "web.xml"));
        writeOptional(outputFolder, new SupportingFile("index.mustache", ("src/main/webapp"), "index.html"));

        writeOptional(outputFolder, new SupportingFile("log4j.mustache", ("conf"), "log4j.properties"));

        writeOptional(outputFolder, new SupportingFile("logback.mustache", ("src/main/resources"), "logback.xml"));

        if ( additionalProperties.containsKey("dateLibrary") ) {
            setDateLibrary(additionalProperties.get("dateLibrary").toString());
            additionalProperties.put(dateLibrary, "true");
        }

        if ( "joda".equals(dateLibrary) ) {
            supportingFiles.add(new SupportingFile("JodaDateTimeProvider.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "JodaDateTimeProvider.java"));
            supportingFiles.add(new SupportingFile("JodaLocalDateProvider.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "JodaLocalDateProvider.java"));
        } else if ( "java8".equals(dateLibrary) ) {
            supportingFiles.add(new SupportingFile("LocalDateTimeProvider.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "LocalDateTimeProvider.java"));
            supportingFiles.add(new SupportingFile("LocalDateProvider.mustache", (sourceFolder + '/' + apiPackage).replace(".", "/"), "LocalDateProvider.java"));
        }
    }

    @Override
    public void addOperationToGroup(String tag, String resourcePath, Operation operation, CodegenOperation co, Map<String, List<CodegenOperation>> operations) {
        String basePath = resourcePath;
        if (basePath.startsWith("/")) {
            basePath = basePath.substring(1);
        }
        int pos = basePath.indexOf("/");
        if (pos > 0) {
            basePath = basePath.substring(0, pos);
        }

        if (basePath == "") {
            basePath = "default";
        } else {
            if (co.path.startsWith("/" + basePath)) {
                co.path = co.path.substring(("/" + basePath).length());
            }
            co.subresourceOperation = !co.path.isEmpty();
        }
        List<CodegenOperation> opList = operations.get(basePath);
        if (opList == null) {
            opList = new ArrayList<CodegenOperation>();
            operations.put(basePath, opList);
        }
        opList.add(co);
        co.baseName = basePath;
    }

    public void hideGenerationTimestamp(boolean hideGenerationTimestamp) {
        this.hideGenerationTimestamp = hideGenerationTimestamp;
    }

}

Thank you in advance for any help!

Jennifer

Solution

this is how java loads classes, specifically with SPI (service provider interface).

There is documentation here:

https://github.com/swagger-api/swagger-codegen#making-your-own-codegen-modules

The problem is that you need to specify both your library as well as the codegen jar, and tell it which class to run. For example:

# assuming your library is under my-codegen/myLibrary/target

java -cp my-codegen/myLibrary/target/myClientCodegen-swagger-codegen-1.0.0.jar \
    modules/swagger-codegen-cli/target/swagger-codegen-cli.jar \
    io.swagger.codegen.SwaggerCodegen generate \
    -l com.my.company.codegen.MyclientcodegenGenerator \
    -o foo \
    -i http://petstore.swagger.io/v2/swagger.json

This will add the codegen library to the classpath, your custom template library, execute the main function (io.swagger.codegen.SwaggerCodegen), and pass in your class as a target..

Comments

[jencoston]

When I run that command I get Error: Could not find or load main class modules.swagger-codegen-cli.target.swagger-codegen-cli.jar.

[jencoston]

It turns out I needed to slightly modify the command and put the path to the jars in quotes. The final command is java -cp "myCodegen-swagger-codegen-1.0.0.jar;swagger-codegen-cli.jar‌​" io.swagger.codegen.SwaggerCodegen generate -l abc -o C:\\Swagger\\Test\\ABCParentProject\\ABCgenerated -i helloAPI.yaml