Swagger Code Generator

⭐⭐⭐ If you would like to contribute, please refer to guidelines and a list of open tasks.⭐⭐⭐

Overview

This is the swagger codegen project, which allows generation of client libraries automatically from a Swagger-compliant server.

Check out Swagger-Spec for additional information about the Swagger project, including additional libraries with support for other languages and more.

Table of contents

• Swagger Code Generator
• Overview
• Table of Contents
• Installation
  • Compatibility
  • Prerequisites
    • OS X Users
  • Building
  • Docker
    • Build and run
    • Build a Node.js server stub
  • Homebrew
• Generators
  • To generate a sample client library
  • Generating libraries from your server
  • Modifying the client library format
  • Making your own codegen modules
  • Where is Javascript???
  • Generating a client from local files
  • Customizing the generator
  • Validating your OpenAPI Spec
  • Generating dynamic html api documentation
  • Generating static html api documentation
  • To build a server stub
    • Node.js
    • PHP Silex
    • Python Flask (Connexion)
    • Ruby Sinatra
    • Scala Scalatra
    • Java JAX-RS
    • Java Spring MVC
  • To build the codegen library
• Online Generators
• Guidelines for Contribution
• License

Compatibility

The OpenAPI Specification has undergone 3 revisions since initial creation in 2010. The swagger-codegen project has the following compatibilies with the OpenAPI Specification:

Swagger Codegen Version	Release Date	OpenAPI Spec compatibility	Notes
2.1.5-SNAPSHOT		1.0, 1.1, 1.2, 2.0	master
2.1.4 (current stable)	2015-10-25	1.0, 1.1, 1.2, 2.0	tag v2.1.4
2.0.17	2014-08-22	1.1, 1.2	tag v2.0.17
1.0.4	2012-04-12	1.0, 1.1	tag v1.0.4

Prerequisites

If you're looking for the latest stable version, you can grab it directly from maven central (you'll need the java 7 runtime):

wget http://repo1.maven.org/maven2/io/swagger/swagger-codegen-cli/2.1.4/swagger-codegen-cli-2.1.4.jar swagger-codegen-cli.jar

java -jar swagger-codegen-cli.jar help

On a mac, it's even easier with brew:

brew install swagger-codegen

To build from source, you need the following installed and available in your $PATH:

• Java 7

• Apache maven 3.0.3 or greater

OS X Users

Don't forget to install Java 7. You probably have 1.6 or 1.8.

Export JAVA_HOME in order to use the supported Java version:

export JAVA_HOME=`/usr/libexec/java_home -v 1.7`
export PATH=${JAVA_HOME}/bin:$PATH

Building

After cloning the project, you can build it from source with this command:

mvn package

Docker

Build and run using docker

git clone https://github.com/swagger-api/swagger-codegen

cd swagger-codegen

./run-in-docker.sh mvn package

Build a Node.js server stub

./run-in-docker.sh generate \
 -i http://petstore.swagger.io/v2/swagger.json \
 -l nodejs \
 -o samples/server/petstore/nodejs

Homebrew

To install, run brew install swagger-codegen

Here is an example usage:

swagger-codegen generate -i http://petstore.swagger.io/v2/swagger.json -l ruby -o /tmp/test/

To generate a sample client library

You can build a client against the swagger sample petstore API as follows:

./bin/java-petstore.sh

(On Windows, run ./bin/windows/java-petstore.bat instead)

This will run the generator with this command:

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate \
  -i http://petstore.swagger.io/v2/swagger.json \
  -l java \
  -o samples/client/petstore/java

with a number of options. You can get the options with the help generate command:

NAME
        swagger generate - Generate code with chosen lang

SYNOPSIS
        swagger generate [(-a <authorization> | --auth <authorization>)]
                [(-c <configuration file> | --config <configuration file>)]
                [-D <system properties>]
                (-i <spec file> | --input-spec <spec file>)
                (-l <language> | --lang <language>)
                [(-o <output directory> | --output <output directory>)]
                [(-t <template directory> | --template-dir <template directory>)]
                [(-v | --verbose)]
                [(-s | --skip-overwrite)]

OPTIONS
        -a <authorization>, --auth <authorization>
            adds authorization headers when fetching the swagger definitions
            remotely. Pass in a URL-encoded string of name:header with a comma
            separating multiple values

        -c <configuration file>, --config <configuration file>
            Path to json configuration file. File content should be in a json
            format {"optionKey":"optionValue", "optionKey1":"optionValue1"...}
            Supported options can be different for each language. Run
            config-help -l {lang} command for language specific config options.

        -D <system properties>
            sets specified system properties in the format of
            name=value,name=value

        -i <spec file>, --input-spec <spec file>
            location of the OpenAPI Spec, as URL or file (required)

        -l <language>, --lang <language>
            client language to generate (maybe class name in classpath,
            required)

        -o <output directory>, --output <output directory>
            where to write the generated files (current dir by default)

        -t <template directory>, --template-dir <template directory>
            folder containing the template files

        -v, --verbose
            verbose mode

        -s , --skip-overwrite
            specifies if the existing files should be overwritten during
            the generation

You can then compile and run the client, as well as unit tests against it:

cd samples/client/petstore/java
mvn package

Other languages have petstore samples, too:

./bin/android-petstore.sh
./bin/java-petstore.sh
./bin/objc-petstore.sh

Generating libraries from your server

It's just as easy--just use the -i flag to point to either a server or file.

Modifying the client library format

Don't like the default swagger client syntax? Want a different language supported? No problem! Swagger codegen processes mustache templates with the jmustache engine. You can modify our templates or make your own.

You can look at modules/swagger-codegen/src/main/resources/${your-language} for examples. To make your own templates, create your own files and use the -t flag to specify your template folder. It actually is that easy.

Making your own codegen modules

If you're starting a project with a new language and don't see what you need, swagger-codegen can help you create a project to generate your own libraries:

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar meta \
  -o output/myLibrary -n myClientCodegen -p com.my.company.codegen

This will write, in the folder output/myLibrary, all the files you need to get started, including a README.md. Once modified and compiled, you can load your library with the codegen and generate clients with your own, custom-rolled logic.

You would then compile your library in the output/myLibrary folder with mvn package and execute the codegen like such:

java -cp output/myLibrary/target/myClientCodegen-swagger-codegen-1.0.0.jar:modules/swagger-codegen-cli/target/swagger-codegen-cli.jar io.swagger.codegen.Codegen

Note the myClientCodegen is an option now, and you can use the usual arguments for generating your library:

java -cp output/myLibrary/target/myClientCodegen-swagger-codegen-1.0.0.jar:modules/swagger-codegen-cli/target/swagger-codegen-cli.jar \
  io.swagger.codegen.Codegen generate -l myClientCodegen\
  -i http://petstore.swagger.io/v2/swagger.json \
  -o myClient

Where is Javascript???

See our javascript library--it's completely dynamic and doesn't require static code generation. There is a third-party component called swagger-js-codegen that can generate angularjs or nodejs source code from a OpenAPI Specification.

❗ On Dec 7th 2015, a Javascript API client generator has been added by @jfiala.

Generating a client from local files

If you don't want to call your server, you can save the OpenAPI Spec files into a directory and pass an argument to the code generator like this:

-i ./modules/swagger-codegen/src/test/resources/2_0/petstore.json

Great for creating libraries on your ci server, from the Swagger Editor... or while coding on an airplane.

Selective generation

You may not want to generate all models in your project. Likewise you may want just one or two apis to be written. If that's the case, you can use system properties to control the output:

The default is generate everything supported by the specific library. Once you enable a feature, it will restrict the contents generated:

# generate only models
java -Dmodels {opts}

# generate only apis
java -Dapis {opts}

# generate only supporting files
java -DsupportingFiles

# generate models and supporting files
java -Dmodels -DsupportingFiles

To control the specific files being generated, you can pass a CSV list of what you want:

# generate the User and Pet models only
-Dmodels=User,Pet

# generate the User model and the supportingFile `StringUtil.java`:
-Dmodels=User -DsupportingFiles=StringUtil.java

When using selective generation, only the templates needed for the specific generation will be used.

Customizing the generator

There are different aspects of customizing the code generator beyond just creating or modifying templates. Each language has a supporting configuration file to handle different type mappings, etc:

$ ls -1 modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/
AbstractTypeScriptClientCodegen.java
AkkaScalaClientCodegen.java
AndroidClientCodegen.java
AndroidVolleyClientCodegen.java
AsyncScalaClientCodegen.java
CSharpClientCodegen.java
ClojureClientCodegen.java
CsharpDotNet2ClientCodegen.java
DartClientCodegen.java
FlashClientCodegen.java
FlaskConnexionCodegen.java
JavaClientCodegen.java
JavaInflectorServerCodegen.java
JavascriptClientCodegen.java
JaxRSServerCodegen.java
JMeterCodegen.java
NodeJSServerCodegen.java
ObjcClientCodegen.java
PerlClientCodegen.java
PhpClientCodegen.java
PythonClientCodegen.java
Qt5CPPGenerator.java
RubyClientCodegen.java
ScalaClientCodegen.java
ScalatraServerCodegen.java
SilexServerCodegen.java
SinatraServerCodegen.java
SlimFrameworkServerCodegen.java
SpringMVCServerCodegen.java
StaticDocCodegen.java
StaticHtmlGenerator.java
SwaggerGenerator.java
SwaggerYamlGenerator.java
SwiftCodegen.java
TizenClientCodegen.java
TypeScriptAngularClientCodegen.java
TypeScriptNodeClientCodegen.java

Each of these files creates reasonable defaults so you can get running quickly. But if you want to configure package names, prefixes, model folders, etc. you can use a json config file to pass the values.

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate \
  -i http://petstore.swagger.io/v2/swagger.json \
  -l java \
  -o samples/client/petstore/java \
  -c path/to/config.json

Supported config options can be different per language. Running config-help -l {lang} will show available options. These options are applied by passing them with `-D{optionName}={optionValue}.

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar config-help -l java

Output

CONFIG OPTIONS
	modelPackage
	    package for generated models

	apiPackage
	    package for generated api classes

	sortParamsByRequiredFlag
	    Sort method arguments to place required parameters before optional parameters. Default: true

	invokerPackage
	    root package for generated code

	groupId
	    groupId in generated pom.xml

	artifactId
	    artifactId in generated pom.xml

	artifactVersion
	    artifact version in generated pom.xml

	sourceFolder
	    source folder for generated code

	localVariablePrefix
	    prefix for generated code members and local variables

	serializableModel
	    boolean - toggle "implements Serializable" for generated models

	library
	    library template (sub-template) to use:
	    <default> - HTTP client: Jersey client 1.18. JSON processing: Jackson 2.4.2
	    jersey2 - HTTP client: Jersey client 2.6
	    feign - HTTP client: Netflix Feign 8.1.1.  JSON processing: Jackson 2.6.3
	    okhttp-gson - HTTP client: OkHttp 2.4.0. JSON processing: Gson 2.3.1
	    retrofit - HTTP client: OkHttp 2.4.0. JSON processing: Gson 2.3.1 (Retrofit 1.9.0)
        retrofit2 - HTTP client: OkHttp 2.5.0. JSON processing: Gson 2.4 (Retrofit 2.0.0-beta2)

Your config file for java can look like

{
  "groupId":"com.my.company",
  "artifactId":"MyClent",
  "artifactVersion":"1.2.0",
  "library":"feign"
}

For all the unspecified options default values will be used.

Another way to override default options is to extend the config class for the specific language. To change, for example, the prefix for the Objective-C generated files, simply subclass the ObjcClientCodegen.java:

package com.mycompany.swagger.codegen;

import io.swagger.codegen.languages.*;

public class MyObjcCodegen extends ObjcClientCodegen {
  static {
    PREFIX = "HELO";
  }
}

and specify the classname when running the generator:

-l com.mycompany.swagger.codegen.MyObjcCodegen

Your subclass will now be loaded and overrides the PREFIX value in the superclass.

Bringing your own models

Sometimes you don't want a model generated. In this case, you can simply specify an import mapping to tell the codegen what not to create. When doing this, every location that references a specific model will refer back to your classes. Note, this may not apply to all languages...

To specify an import mapping, use the --import-mappings argument and specify the model-to-import logic as such:

--import-mappings Pet=my.models.MyPet

Or for multiple mappings:

Pet=my.models.MyPet,Order=my.models.MyOrder

Validating your OpenAPI Spec

You have options. The easiest is to use our online validator which not only will let you validate your spec, but with the debug flag, you can see what's wrong with your spec. For example:

http://online.swagger.io/validator/debug?url=http://petstore.swagger.io/v2/swagger.json

Generating dynamic html api documentation

To do so, just use the -l dynamic-html flag when reading a spec file. This creates HTML documentation that is available as a single-page application with AJAX. To view the documentation:

cd samples/dynamic-html/
npm install
node .

Which launches a node.js server so the AJAX calls have a place to go.

Generating static html api documentation

To do so, just use the -l html flag when reading a spec file. This creates a single, simple HTML file with embedded css so you can ship it as an email attachment, or load it from your filesystem:

cd samples/html/
open index.html

To build a server stub

You can also use the codegen to generate a server for a couple different frameworks. Take a look here:

Node.js

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate \
  -i http://petstore.swagger.io/v2/swagger.json \
  -l nodejs \
  -o samples/server/petstore/nodejs

PHP Silex

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate \
  -i http://petstore.swagger.io/v2/swagger.json \
  -l silex \
  -o samples/server/petstore/silex

Python Flask (Connexion)

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate \
  -i http://petstore.swagger.io/v2/swagger.json \
  -l flaskConnexion \
  -o samples/server/petstore/flaskConnexion

Ruby Sinatra

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate \
  -i http://petstore.swagger.io/v2/swagger.json \
  -l sinatra \
  -o samples/server/petstore/sinatra

Scala Scalatra

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate \
  -i http://petstore.swagger.io/v2/swagger.json \
  -l scalatra \
  -o samples/server/petstore/scalatra

Java JAX-RS

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate \
  -i http://petstore.swagger.io/v2/swagger.json \
  -l jaxrs \
  -o samples/server/petstore/jaxrs

Java Spring MVC

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate \
  -i http://petstore.swagger.io/v2/swagger.json \
  -l spring-mvc \
  -o samples/server/petstore/spring-mvc

To build the codegen library

This will create the swagger-codegen library from source.

mvn package

Note! The templates are included in the library generated. If you want to modify the templates, you'll need to either repackage the library OR specify a path to your scripts

Online generators

One can also generate API client or server using the online generators (https://generator.swagger.io)

For example, to generate Ruby API client, simply send the following HTTP request using curl:

curl -X POST -H "content-type:application/json" -d '{"swaggerUrl":"http://petstore.swagger.io/v2/swagger.json"}' https://generator.swagger.io/api/gen/clients/ruby

Then you will receieve a JSON response with the URL to download the zipped code.

Guidelines for Contribution

Please refer to this page

License

Copyright 2015 SmartBear Software

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.