Swagger-gen is a simple tool for generating code from a swagger spec.
It can quickly generate boilerplate code in your application in any number of different languages.
A library for easy swagger code generation using Mustache as the template engine.
There is an existing Java generator for swagger but Clojure seems a much leaner and easier language for the task.
- Lightweight and simple DSL for traversing Swagger Specs
- Clean and simple code gen based on templates
- More complex code generation through Clojure functions
This example generates HTML docs from the canonical petstore example.
We start with a simple mustache template which contains placeholders for our final HTML file
<html>
<head>
<title>{{info.title}}</title>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css" rel="stylesheet"/>
</head>
<body>
<div class="container">
<h1>{{info.title}}</h1>
<p>{{info.description}}</p>
<table class="table table-striped">
<tr>
<th>Method</th>
<th>Path</th>
<th>Operation ID</th>
</tr>
{{#paths}}
<tr>
<td>{{method}}</td>
<td>{{path}}</td>
<td>{{operationId}}</td>
</tr>
{{/paths}}
</table>
</div>
</body>
</html>For more complex code generation tasks we can write custom functions to assist with the generation.
The only real "logic" here is adding some additional data to the swagger structure to make rendering in the templates easier. For example, in the example below we have a custom function that renders a swagger path as a scala case class string.
(ns swagger-gen.examples.scala.generator
(:require [swagger-gen.scala :as scala]
[swagger-gen.core :refer [render-swagger]]))
(defn expand-model
"Add some additional data here so we don't have to do any
tricky logic in the template"
[model]
(assoc model :class (scala/render-case-class model)
:arglen (count (:args model))))
(defn -main
"An example using custom rendering logic to generate model code in Scala"
[]
(let [spec "resources/swagger/petstore.yaml"
template "src/swagger_gen/examples/scala/template.mustache"
additional-params { :namespace "com.google.service.models" }]
(print
(render-swagger spec template
(fn [spec]
(merge additional-params
(assoc spec :definitions
(map expand-model (:definitions spec)))))))))Swagger gen templates are just simple mustache files.
package {{namespace}}
import spray.json.DefaultJsonProtocol
{{#definitions}}
{{class}}
object {{name}} extends DefaultJsonProtocol {
implicit val format = jsonFormat{{arglen}}({{name}}.apply)
}
{{/definitions}}
Copyright © 2016 Owain Lewis
Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.