R10k's dynamic deployments work best with a workflow that understands and
respects how r10k works, to prevent automation and manual processes from
conflicting. Your workflow will need to be customized to meet your team's
skills, tools, and needs. This guide describes a generic workflow that can
be customized easily.

This guide assumes that each of your modules is in a separate repository 
and that the `Puppetfile` is in its own repo called the
[Control Repo](http://technoblogic.io/blog/2014/05/16/r10k-control-repos/).
All module repos have a primary branch of *master* and the Control's primary
branch is *production*. All changes are made through r10k and no user makes
manual changes to the environments under **/etc/puppet**.

Adding New Modules
------------------

This workflow is useful when adding a forge or internally-developed module
to your puppet environment.

### Create new feature branch

Create a new feature branch in your module repositories. Do this for each
repository, including the control repository, that will reference the new
module. You do not need to do so for modules that are not being edited.

```git checkout -b feature```

If you are simply adding the module at this time and not referencing it in
other modules or manifests, only the Control repo requires a new branch.

### Add new module and branches to control repo

The new module is added to the control repository's `Puppetfile` like so:

```
# Forge modules:
mod "puppetlabs/ntp"

# Your modules:
mod "custom_facts",
  :git => "git://github.com/user/custom_facts"
```

For any existing modules that you branched, add a reference to the new branch
name. Don't forget the comma at the end of the *:git* value.

```
mod "other_module",
  :git => "git://github.com/user/other_module",
  :ref => "feature"
```

### Reference new module in manifests, modules, and hiera

If you are simply adding the module at this time and not referencing it in
other modules or manifests, you may skip this step.

Edit your existing manifests, modules, and hiera as needed to make sure of
the new module.

### Deploy environments

Save all your changes in each module repo. Commit and push the changes upstream:

```
git commit -a -m ‘Add feature reference to module’
git push origin feature
```

Commit and push the change in your control repo upstream:

```
git commit -a -m ‘Add module puppetlabs/ntp to branch feature'
git push origin feature
```

Finally, deploy the environments via r10k. This step must occur on the master:

```r10k deploy environment -p```

Add the **-v** option for verbosity if you need to troubleshoot any errors. The
new branch should be located at `$environmentpath/feature`.


### Test the new module branches

If you are simply adding the module at this time and not referencing it in
other modules or manifests, you may skip this step.

Run the puppet agent against the new environment from at least two nodes, one
that should not be impacted by change and one that should be impacted.

```puppet agent -t --environment feature```

Verify that catalog compilation succeeds and that you are satisfied that the
effective changes match your expected changes. Repeat the steps above until
you are satisfied with the results.

### Merge changes

In each of the changed modules and the control repo, checkout the main branch,
merge, and push changes to the master/production branch.

```
# Module repos
git checkout master
git merge feature
git push origin master

# Control repo
git checkout production
git merge feature
vi Puppetfile
# Remove all :ref's pointing to 'feature'. Don't forget the trailing commas
# on the :git statements
git commit -a -m 'Remove refs to feature branch for module puppetlabs/ntp'
git push origin production
```

If you are simply adding the module at this time and not referencing it in
other modules or manifests, you are now finished.

### Cleanup feature branches

You may skip this step for long-lived branches, however most feature branches
should be short-lived and can be pruned once testing and merging is complete.

Remove the old branches in each repo:

```
git branch -D repo
git push origin :repo
```

Deploy via r10k on the master and ensure there are no errors. The *feature*
dynamic environment will no longer exist at `$environmentpath/feature` if you
deleted the branch in your Control repo.

```r10k deploy environment -p```

Editing existing Modules
------------------------

When editing your own existing modules, this workflow should be followed.

### Create new feature branches

Create a new feature branch in your module repositories. Do this in the edited
module, the control repository, and in each module that will reference the
updated module. You do not need to do so for modules that are not being edited.

```git checkout -b feature```

### Update control repo to reference new branch

For all modules that you branched, add a reference to the new branch name to
the `Puppetfile` in your Control repo. Don't forget the comma at the end of
the *:git* value.

```
mod "other_module",
  :git => "git://github.com/user/other_module",
  :ref => "feature"
```

### Modify existing module, references to module

Make the required changes to your existing module. Edit your existing manifests,
modules, and hiera as needed to make sure of the updated module.

### Deploy environments

Save all your changes in each modified repo. Commit and push the changes upstream:

```
git commit -a -m ‘Add feature reference to module’
git push origin feature
```

Commit and push the change in your control repo upstream:

```
git commit -a -m ‘Add module puppetlabs/ntp to branch feature'
git push origin feature
```

Finally, deploy the environments via r10k. This step must occur on the master:

```r10k deploy environment -p```

Add the *-v* option for verbosity if you need to troubleshoot any errors. The
new branch should be located at `$environmentpath/feature`.

### Test the new module branches

Run the puppet agent against the new environment from at least two nodes, one
that should not be impacted by change and one that should be impacted.

```puppet agent -t --environment feature```

Verify that catalog compilation succeeds and that you are satisfied that the
effective changes match your expected changes. Repeat the steps above until
you are satisfied with the results.

### Merge changes

In each of the changed module repos, checkout the main branch and merge.

```
# Module repos
git checkout master
git merge feature
git push origin master
```

In the Control repo, check out production. Do NOT merge the feature branch as it
now references the incorrect branch for each git repo, and no other changes
were made (unlike a new module, where a new repo is referenced).

```
# Control repo
git checkout production
```

### Cleanup feature branches

You may skip this step for long-lived branches, however most feature branches
should be short-lived and can be pruned once testing and merging is complete.

Remove the old branches in each repo:

```
git branch -D repo
git push origin :repo
```

Redeploy with r10k on your Puppet Master and ensure there are no errors. The *feature*
dynamic environment should no longer exist at `$environmentpath/feature`.

```r10k deploy environment -p```

Customize Your Workflow
-----------------------

This guide is very generic in nature. Use it as a template and expand and
modify it to fit your team, your tools, and your company culture. Above all,
be consistent in your methodology.
