initializr/README.adoc

= Spring Initializr image:https://badges.gitter.im/spring-io/initializr.svg[link="https://gitter.im/spring-io/initializr?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge"]

:wiki: https://github.com/spring-io/initializr/wiki
:boot-doc: http://docs.spring.io/spring-boot/docs/current/reference/htmlsingle
:code: https://github.com/spring-io/initializr/blob/master

Spring Initializr provides an extensible API to generate quickstart projects. It also
provides a configurable service: you can see our default instance at
link:https://start.spring.io[]. It provides a simple web UI to configure the project
to generate and endpoints that you can use via plain HTTP.

Spring Initializr also exposes an endpoint that serves its
{wiki}/Metadata-format[metadata] in a well-known format to allow third-party
clients to provide the necessary assistance.

Finally, Initializr offers a configuration structure to define all the aspects related
to the project to generate: list of dependencies, supported java and boot versions, etc. Check
the {code}/initializr-service/src/main/resources/application.yml[configuration of our instance] for an example. Such
configuration is {wiki}/Configuration-format[also described in details on the wiki].

NOTE: We use the continuous deployment technique to manage our instance; check the
https://github.com/spring-io/initializr/milestones[milestones page] for an overview of changes

== Modules

Spring Initializr has the following modules:

* `initializr-generator`: standalone project generation library that can be reused in
many environments (including embedded in your own project)
* `initializr-web`: REST endpoints and web interface
* `initializr-actuator`: optional module to provide statistics and metrics on project
generation

`initializr-service` is an additional module that represents the production instance that
is available at link:https://start.spring.io[]. It is not enabled by default but you can
enable the `full` profile in your IDE to easily run it locally.

== Supported interfaces

Spring Initializr can be used as follows:

* With your browser (i.e. link:https://start.spring.io[])
* In your IDE if you are using STS, IntelliJ IDEA Ultimate or NetBeans (with
https://github.com/AlexFalappa/nb-springboot[this plugin])
* On the command-line with {boot-doc}/#cli-init[the Spring Boot CLI] or simply with `cURL` or `HTTPie`

[TIP]
====
You can "curl" an instance to get a usage page with examples (try `curl start.spring.io`)
====

== Generating a project

If you click on "Generate Project" on the web ui of our instance, it will download a project
archive with a Maven-based project and the necessary infrastructure to start a basic Spring
Boot app.

You could achieve the same result with a simple `curl` command

[source,bash]
----
$ curl https://start.spring.io/starter.zip -o demo.zip
----

The web ui exposes a bunch of options that you can configure. These are mapped to the following
request attributes:

* Basic information for the generated project: `groupId`, `artifactId`, `version`, `name`,
`description` and `packageName`
** The `name` attribute is also used to generate a default application name. The logic is
that the name of the application is equal to the `name` attribute with an `Application`
suffix (unless said suffix is already present). Of course, if the specified name contains
an invalid character for a java identifier, `Application` is used as fallback.
** The `artifactId` attribute not only defines the identifier of the project in the build but
also the name of the generated archive.
* `dependencies` (or `style`): the identifiers of the dependencies to add to the project. Such
identifiers are defined through configuration and are exposed in the <<metadata,metadata>>.
* `type`: the _kind_ of project to generate (e.g. `maven-project`). Again, each service
exposes an arbitrary number of supported types and these are available in the
<<metadata,metadata>>.
* `javaVersion`: the language level (e.g. `1.8`).
* `bootVersion`: the Spring Boot version to use (e.g. `1.2.0.RELEASE`).
* `language`: the programming language to use (e.g. `java`).
* `packaging`: the packaging of the project (e.g. `jar`).
* `applicationName`: the name of the application class (inferred by the `name` attribute by
default).
* `baseDir`: the name of the base directory to create in the archive. By default, the project
is stored in the root.

This command generates an `another-project` directory holding a Gradle web-based
Groovy project using the actuator:

[source,bash]
----
$ curl https://start.spring.io/starter.tgz -d dependencies=web,actuator \
-d language=groovy -d type=gradle-project -d baseDir=another-project | tar -xzvf -
----

NOTE: The `/starter.tgz` endpoint offers the same feature as `/starter.zip` but generates
a compressed tarball instead.

You could use this infrastructure to create your own client since the project is generated
via a plain HTTP call.

[[customize-form]]
== Customize form inputs

You can share or bookmark URLs that will automatically customize form inputs. For instance,
the following URL from the default instance uses `groovy` by default and set the name
to `Groovy Sample`:

[source,bash]
----
https://start.spring.io/#!language=groovy&name=Groovy%20Sample
----

The following hashbang parameters are supported: `type`, `groupId`, `artifactId`, `name`,
`description`, `packageName`, `packaging`, `javaVersion` and `language`. Review the section
above for a description of each of them.

[[metadata]]
== Service metadata

The service metadata is used by the web UI and is exposed to ease the creation of
third-party clients. You can grab the metadata by _curling_ the root

[source,bash]
----
$ curl -H 'Accept: application/json' https://start.spring.io
----

NOTE: As stated above, if you use `curl` without an accept header, you'll retrieve a human
readable text version of the metadata. `HTTPie` is also supported.

The metadata basically lists the _capabilities_ of the service, that is the available
options for all request parameters (`dependencies`, `type`, `bootVersion`, etc.) The web
UI uses that information to initialize the select options and the tree of available
dependencies.

The metadata also lists the default values for simple _text_ parameter (i.e. the default
`name` for the project).

NOTE: More details about the structure of the metadata are {wiki}/Metadata-format[available
on the wiki].

== Running your own instance

You can easily run your own instance. The `initializr-web` modules uses Spring Boot so when it
is added to a project, it will trigger the necessary auto-configuration to deploy the service.

You first need to create or update your configuration to define the necessary attributes that
your instance will use. Again, check the wiki for a {wiki}/Configuration-format[description
of the configuration] and {code}/initializr-service/application.yml[review our own config] for
a sample.

You can integrate the library in a traditional Java-based project or by writing the super-simple
script below

[source,groovy]
----
package org.acme.myapp

@Grab('io.spring.initializr:initializr-web:1.0.0.BUILD-SNAPSHOT')
@Grab('spring-boot-starter-web')
class YourInitializrApplication { }
----

NOTE: Spring Initializr is not available on Maven central yet so you will have to build
it <<build,from source>> in order to use it in your own environment.

Once you have created that script (`my-instance.groovy`), place your configuration in the same
directory and simply execute this command to start the service:

[source,bash]
----
$ spring run my-instance.groovy
----

You may also want to <<run-app,run the default instance locally>>.


[[build]]
== Building from Source

You need Java (1.8 or better), Maven 3.2+ and a bash-like shell.

[[building]]
=== Building

Just invoke the build at the root of the project

[indent=0]
----
    $ mvn clean install
----

If you want to run the smoke tests using Geb, you need to enable the
`smokeTests` profile. Firefox should also be installed on your machine:

[indent=0]
----
    $ mvn verify -PsmokeTests
----

If you want to build both the library and the service, you can enable the `full` profile:

[indent=0]
----
    $ mvn clean install -Pfull
----


[[run-app]]
=== Running the app locally

Once you have <<building, built the library>>, you can easily start the app as any other
Spring Boot app from the `initializr-service` directory:

[indent=0]
----
    $ cd initializr-service
    $ mvn spring-boot:run
----

[[run-ide]]
=== Running the app in an IDE

You should be able to import the projects into your IDE with no
problems (STS with the m2e Groovy compiler support or IntelliJ IDEA
definitely work). Once there you can run the `initializr-service` from
its main method, debug it, and it will reload if you make changes to
other modules. (You may need to manually enable the "full" profile.)
This is the recommended way to operate while you are developing the
application, especially the UI.


## Deploying to Cloud Foundry

If you are on a Mac and using http://brew.sh/[homebrew], install the Cloud Foundry CLI:

[indent=0]
----
    $ brew install cloudfoundry-cli
----

Alternatively, download a suitable binary for your platform from
https://console.run.pivotal.io/tools[Pivotal Web Services].

You should ensure that the application name and URL (name and host values) are suitable for
your environment before running `cf push`.

First, make sure that you have <<building, built the library>>, then make sure first that
the jar has been created:

[indent=0]
----
    $ cd initializr-service
    $ mvn package
----

Once the jar has been created, you can push the application:

[indent=0]
----
    $ cf push your-initializr -p target/initializr-service.jar
----

== License
Spring Initializr is Open Source software released under the
http://www.apache.org/licenses/LICENSE-2.0.html[Apache 2.0 license].