enkan

Enkan(円環) is a microframework implemented middleware pattern like ring or connect.

Concept

• Minimal (Simple made easy)
• Ease of development
• Ease of operation

Minimal

• Middleware pattern
• No configuration files
• Avoid blackbox
• Less annotations
• Less library dependencies
• Single instance (Middlewares and compoments, controller)

Ease of development

• Faster startup (Preventing to scan classes)
• Reloading classes without restarting JVM
• Trace execution of middlewares
• Alert misconfiguration

Ease of operation

• Starting server is fast. (~3 seconds)
• Resetting application is very fast. (~1 seconds)
• Run-time change predicates of middleware on the REPL

Requirements

• Java8
• Java EE 7 Specification

Middleware

• Service Unavailable
• Session
• Flash
• Cookie
• Parsing parameters
• Trace log
• Populating form (kotowari)
• JSR-303 Validation (kotowari)
• Routing like Rails (kotowari)
• Injecting components to a controller (kotowari)

Components

• HikariCP
• Flyway
• Freemarker
• Jetty
• Undertow
• Doma2

Using enkan and kotowari, your code is following

public class ExampleController {
    @Inject
    private TemplateEngineComponent templateEngine;

    @Inject
    private DomaDaoProvider daoProvider;

    public HttpResponse index(ExampleForm form) {
        CustomerDao customerDao = daoProvider.get(CustomerDao.class);
        Customer customer = customerDao.selectById(form.getId());
        return templateEngine.render("example",
                "customer", customer);
    }
}

Get started

Add sonatype snapshots repository to your pom.xml

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

Manual

EnkanSystem

Enkan system is consist of components. Component is a singleton instance sharing data between requests.

EnkanSystem.of(
    "doma", new DomaProvider(),
    "flyway", new FlywayMigration(),
    "template", new FreemarkerComponent(),
    "datasource", new HikariCPComponent(OptionMap.of("uri", "jdbc:h2:mem:test")),
    "app", new ApplicationComponent("kotowari.example.MyApplicationFactory"),
    "http", builder(new JettyComponent())
        .set(JettyComponent::setPort, Env.getInt("PORT", 3000))
        .build()
).relationships(
    component("http").using("app"),
    component("app").using("template", "doma", "datasource"),
    component("doma").using("datasource"),
    component("flyway").using("datasource")
);

Application

An application has a stack of middlewares. A middleware is a single instance. By use method, the middleware is used by application.

app.use(ANY("/secret"), new AuthenticateMiddleware());

REPL

Enkan system is operated by a REPL interface.

• Start a server REPL> /start [pool-1-thread-1] INFO com.zaxxer.hikari.HikariDataSource - HikariPool-0 - is starting. [pool-1-thread-1] INFO org.flywaydb.core.internal.util.VersionPrinter - Flyway 3.2.1 by Boxfuse [pool-1-thread-1] INFO org.flywaydb.core.internal.dbsupport.DbSupportFactory - Database: jdbc:h2:mem:test (H2 1.4) [pool-1-thread-1] INFO org.flywaydb.core.internal.command.DbValidate - Validated 1 migration (execution time 00:00.019s) [pool-1-thread-1] INFO org.flywaydb.core.internal.metadatatable.MetaDataTableImpl - Creating Metadata table: "PUBLIC"."schema_version" [pool-1-thread-1] INFO org.flywaydb.core.internal.command.DbMigrate - Current version of schema "PUBLIC": << Empty Schema >> [pool-1-thread-1] INFO org.flywaydb.core.internal.command.DbMigrate - Migrating schema "PUBLIC" to version 1 - CreateCustomer [pool-1-thread-1] INFO org.flywaydb.core.internal.command.DbMigrate - Successfully applied 1 migration to schema "PUBLIC" (execution time 00:00.059s). 2 02, 2016 7:58:35 午後 org.hibernate.validator.internal.util.Version <clinit> INFO: HV000001: Hibernate Validator 5.2.2.Final [pool-1-thread-1] INFO org.eclipse.jetty.util.log - Logging initialized @2688228ms [pool-1-thread-1] INFO org.eclipse.jetty.server.Server - jetty-9.3.5.v20151012 REPL> [pool-1-thread-1] INFO org.eclipse.jetty.server.ServerConnector - Started [email protected]{HTTP/1.1,[http/1.1]}{0.0.0.0:3000} [pool-1-thread-1] INFO org.eclipse.jetty.server.Server - Started @2688295ms
• Stop a server
• Reload an application
• Show routing information REPL> /routes app GET / {controller=class kotowari.example.controller.ExampleController, action=index} GET /m1 {controller=class kotowari.example.controller.ExampleController, action=method1} GET /m2 {controller=class kotowari.example.controller.ExampleController, action=method2} GET /m3 {controller=class kotowari.example.controller.ExampleController, action=method3} GET /m4 {controller=class kotowari.example.controller.ExampleController, action=method4} POST /login {controller=class kotowari.example.controller.LoginController, action=login}
• Show middleware stack REPL> /middleware app list ANY defaultCharset ([email protected]) NONE serviceUnavailable ([email protected]) ANY stacktrace ([email protected]) ANY trace ([email protected]) ANY contentType ([email protected]) ANY httpStatusCat ([email protected]) ANY params ([email protected]) ANY normalization ([email protected]) ANY cookies ([email protected]) ANY session ([email protected]) ANY resource ([email protected]) ANY routing ([email protected]) ANY domaTransaction ([email protected]) ANY form ([email protected]) ANY validateForm ([email protected]) ANY htmlRenderer ([email protected]) ANY controllerInvoker ([email protected])
• Rewrite a predicate of middleware REPL> /middleware app predicate serviceUnavailable ANY REPL> /middleware app list ANY defaultCharset ([email protected]) ANY serviceUnavailable ([email protected]) ANY stacktrace ([email protected])

Enkan REPL can attach to a running process.

enkan> /connect 35677
Connected to server (port = 35677)

• TODO: Migrate to JShell.

Kotowari

Kotowari is a web routing framework on Enkan.

It’s rails-like syntax in the routing definition.

Routes routes = Routes.define(r -> {
    r.get("/").to(ExampleController.class, "index");
    r.get("/m1").to(ExampleController.class, "method1");
    r.get("/m2").to(ExampleController.class, "method2");
    r.get("/m3").to(ExampleController.class, "method3");
    r.get("/m4").to(ExampleController.class, "method4");
    r.post("/login").to(LoginController.class, "login");
    r.resource(CustomerController.class);
}).compile();