docs/README.md

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## Setup

Samza's documentation uses Jekyll to build a website out of markdown pages. Prerequisites:

1. You need [Ruby](https://www.ruby-lang.org/) installed on your machine (run `ruby --version` to check)
2. Install [Bundler](http://bundler.io/) by running `sudo gem install bundler`
3. To install Jekyll and its dependencies, change to the `docs` directory and run `bundle install`

To serve the website on [localhost:4000](http://localhost:4000/):

    bundle exec jekyll serve --watch --baseurl

To compile the website in the \_site directory, execute:

    bundle exec jekyll build

To test the site, run:

    bundle exec jekyll serve --watch --baseurl

## Versioning

If you're working with versioned content (anything in the learn or img directories), you'll also need to run a script that generates the appropriate directories:

      _docs/local-site-test.sh

The local-site-test.sh script must be run every time a change is made to versioned content locally in order to trigger a refresh with Jekyll.

Keep in mind that versioned content in older versions links to samza.apache.org, not the localhost:4000. This is because they are not updated by your branch and are using the values in SVN instead.

To add a new version, change the version number in _config.yml. All links in pages should use {{site.version}}, not hard-coded version number.

## Javadocs

To auto-generate the latest Javadocs, run:

    bin/generate-javadocs.sh

## Publish

To build and publish the website to Samza's Apache SVN repository, run:

    bin/publish-site.sh "updating welcome page" criccomini

This command will re-build the Javadocs and website, checkout https://svn.apache.org/repos/asf/samza/site/ locally, copy the site into the directory, and commit the changes.

## Release-new-version Website Checklist

Assume we want to release x.x.x and the next release is y.y.y in master, need to work on two branches: x.x.x and master.

Following can be done when updating the gradle.properties file

1. in x.x.x branch,

    * modify the docs/_config.yml to make the "version" and "latest-release" to x.x.x

    * remove "git checkout latest" in docs/startup/hello-samza/versioned/index.md

2. in master branch,

    * modify the docs/_config.yml to make the "latest-release" to x.x.x

    * add the x.x.x release to Archive category in docs/_layout/default.html and x.x.x release part in docs/archive/index.html

    * update the download page to use x.x.x release

    * update the version number in "tar -xvf ./target/hello-samza-y.y.y-dist.tar.gz -C deploy/samza" in docs/startup/hello-samza/versioned/index.md

After apache mirrors pick up the new release,

3. in x.x.x branch, run bin/publish-site.sh "updating welcome page" criccomini

4. in master branch, run bin/publish-site.sh "updating welcome page" criccomini