Input variable for replication_group_id (#28)

* adding an input variable for replication_group_id

* fix formatting

* updating docs

README.md

 <!-- This file was automatically generated by the `build-harness`. Make all changes to `README.yaml` and run `make readme` to rebuild this file. -->
+[![README Header][readme_header_img]][readme_header_link]
 
-
-[![Cloud Posse](https://cloudposse.com/logo-300x69.svg)](https://cloudposse.com)
+[![Cloud Posse][logo]](https://cpco.io/homepage)
 
 # terraform-aws-elasticache-redis [![Build Status](https://travis-ci.org/cloudposse/terraform-aws-elasticache-redis.svg?branch=master)](https://travis-ci.org/cloudposse/terraform-aws-elasticache-redis) [![Latest Release](https://img.shields.io/github/release/cloudposse/terraform-aws-elasticache-redis.svg)](https://github.com/cloudposse/terraform-aws-elastic-beanstalk-environment/releases/latest) [![Slack Community](https://slack.cloudposse.com/badge.svg)](https://slack.cloudposse.com)
 
@@ -11,7 +11,17 @@ Terraform module to provision an [`ElastiCache`](https://aws.amazon.com/elastica
 
 ---
 
-This project is part of our comprehensive ["SweetOps"](https://docs.cloudposse.com) approach towards DevOps. 
+This project is part of our comprehensive ["SweetOps"](https://cpco.io/sweetops) approach towards DevOps. 
+[<img align="right" title="Share via Email" src="https://docs.cloudposse.com/images/ionicons/ios-email-outline-2.0.1-16x16-999999.svg"/>][share_email]
+[<img align="right" title="Share on Google+" src="https://docs.cloudposse.com/images/ionicons/social-googleplus-outline-2.0.1-16x16-999999.svg" />][share_googleplus]
+[<img align="right" title="Share on Facebook" src="https://docs.cloudposse.com/images/ionicons/social-facebook-outline-2.0.1-16x16-999999.svg" />][share_facebook]
+[<img align="right" title="Share on Reddit" src="https://docs.cloudposse.com/images/ionicons/social-reddit-outline-2.0.1-16x16-999999.svg" />][share_reddit]
+[<img align="right" title="Share on LinkedIn" src="https://docs.cloudposse.com/images/ionicons/social-linkedin-outline-2.0.1-16x16-999999.svg" />][share_linkedin]
+[<img align="right" title="Share on Twitter" src="https://docs.cloudposse.com/images/ionicons/social-twitter-outline-2.0.1-16x16-999999.svg" />][share_twitter]
+
+
+[![Terraform Open Source Modules](https://docs.cloudposse.com/images/terraform-open-source-modules.svg)][terraform_modules]
+
 
 
 It's 100% Open Source and licensed under the [APACHE2](LICENSE).
@@ -22,6 +32,11 @@ It's 100% Open Source and licensed under the [APACHE2](LICENSE).
 
 
 
+We literally have [*hundreds of terraform modules*][terraform_modules] that are Open Source and well-maintained. Check them out! 
+
+
+
+
 
 
 
@@ -109,6 +124,7 @@ Available targets:
 | notification_topic_arn | Notification topic arn | string | `` | no |
 | parameter | A list of Redis parameters to apply. Note that parameters may differ from one Redis family to another | list | `<list>` | no |
 | port | Redis port | string | `6379` | no |
+| replication_group_id | Replication group ID with the following constraints:  A name must contain from 1 to 20 alphanumeric characters or hyphens.   The first character must be a letter.   A name cannot end with a hyphen or contain two consecutive hyphens. | string | `` | no |
 | security_groups | AWS security group ids | list | `<list>` | no |
 | stage | Stage | string | `default` | no |
 | subnets | AWS subnet ids | list | `<list>` | no |
@@ -135,26 +151,38 @@ Available targets:
 
 File a GitHub [issue](https://github.com/cloudposse/terraform-aws-elasticache-redis/issues), send us an [email][email] or join our [Slack Community][slack].
 
+[![README Commercial Support][readme_commercial_support_img]][readme_commercial_support_link]
+
 ## Commercial Support
 
 Work directly with our team of DevOps experts via email, slack, and video conferencing. 
 
 We provide [*commercial support*][commercial_support] for all of our [Open Source][github] projects. As a *Dedicated Support* customer, you have access to our team of subject matter experts at a fraction of the cost of a full-time engineer. 
 
-[![E-Mail](https://img.shields.io/badge/email-hello@cloudposse.com-blue.svg)](mailto:hello@cloudposse.com)
+[![E-Mail](https://img.shields.io/badge/email-hello@cloudposse.com-blue.svg)][email]
 
 - **Questions.** We'll use a Shared Slack channel between your team and ours.
 - **Troubleshooting.** We'll help you triage why things aren't working.
 - **Code Reviews.** We'll review your Pull Requests and provide constructive feedback.
 - **Bug Fixes.** We'll rapidly work to fix any bugs in our projects.
-- **Build New Terraform Modules.** We'll develop original modules to provision infrastructure.
+- **Build New Terraform Modules.** We'll [develop original modules][module_development] to provision infrastructure.
 - **Cloud Architecture.** We'll assist with your cloud strategy and design.
 - **Implementation.** We'll provide hands-on support to implement our reference architectures. 
 
 
-## Community Forum
 
-Get access to our [Open Source Community Forum][slack] on Slack. It's **FREE** to join for everyone! Our "SweetOps" community is where you get to talk with others who share a similar vision for how to rollout and manage infrastructure. This is the best place to talk shop, ask questions, solicit feedback, and work together as a community to build *sweet* infrastructure.
+## Terraform Module Development
+
+Are you interested in custom Terraform module development? Submit your inquiry using [our form][module_development] today and we'll get back to you ASAP.
+
+
+## Slack Community
+
+Join our [Open Source Community][slack] on Slack. It's **FREE** for everyone! Our "SweetOps" community is where you get to talk with others who share a similar vision for how to rollout and manage infrastructure. This is the best place to talk shop, ask questions, solicit feedback, and work together as a community to build totally *sweet* infrastructure.
+
+## Newsletter
+
+Signup for [our newsletter][newsletter] that covers everything on our technology radar.  Receive updates on what we're up to on GitHub as well as awesome new projects we discover. 
 
 ## Contributing
 
@@ -164,7 +192,7 @@ Please use the [issue tracker](https://github.com/cloudposse/terraform-aws-elast
 
 ### Developing
 
-If you are interested in being a contributor and want to get involved in developing this project or [help out](https://github.com/orgs/cloudposse/projects/3) with our other projects, we would love to hear from you! Shoot us an [email](mailto:hello@cloudposse.com).
+If you are interested in being a contributor and want to get involved in developing this project or [help out](https://cpco.io/help-out) with our other projects, we would love to hear from you! Shoot us an [email][email].
 
 In general, PRs are welcome. We follow the typical "fork-and-pull" Git workflow.
 
@@ -179,7 +207,7 @@ In general, PRs are welcome. We follow the typical "fork-and-pull" Git workflow.
 
 ## Copyright
 
-Copyright © 2017-2018 [Cloud Posse, LLC](https://cloudposse.com)
+Copyright © 2017-2018 [Cloud Posse, LLC](https://cpco.io/copyright)
 
 
 
@@ -220,26 +248,16 @@ All other trademarks referenced herein are the property of their respective owne
 
 ## About
 
-This project is maintained and funded by [Cloud Posse, LLC][website]. Like it? Please let us know at <hello@cloudposse.com>
+This project is maintained and funded by [Cloud Posse, LLC][website]. Like it? Please let us know by [leaving a testimonial][testimonial]!
 
-[![Cloud Posse](https://cloudposse.com/logo-300x69.svg)](https://cloudposse.com)
+[![Cloud Posse][logo]][website]
 
-We're a [DevOps Professional Services][hire] company based in Los Angeles, CA. We love [Open Source Software](https://github.com/cloudposse/)!
+We're a [DevOps Professional Services][hire] company based in Los Angeles, CA. We ❤️  [Open Source Software][we_love_open_source].
 
-We offer paid support on all of our projects.  
+We offer [paid support][commercial_support] on all of our projects.  
 
-Check out [our other projects][github], [apply for a job][jobs], or [hire us][hire] to help with your cloud strategy and implementation.
+Check out [our other projects][github], [follow us on twitter][twitter], [apply for a job][jobs], or [hire us][hire] to help with your cloud strategy and implementation.
 
-  [docs]: https://docs.cloudposse.com/
-  [website]: https://cloudposse.com/
-  [github]: https://github.com/cloudposse/
-  [commercial_support]: https://github.com/orgs/cloudposse/projects
-  [jobs]: https://cloudposse.com/jobs/
-  [hire]: https://cloudposse.com/contact/
-  [slack]: https://slack.cloudposse.com/
-  [linkedin]: https://www.linkedin.com/company/cloudposse
-  [twitter]: https://twitter.com/cloudposse/
-  [email]: mailto:hello@cloudposse.com
 
 
 ### Contributors
@@ -261,3 +279,36 @@ Check out [our other projects][github], [apply for a job][jobs], or [hire us][hi
   [christopherriley_avatar]: https://github.com/christopherriley.png?size=150
 
 
+
+[![README Footer][readme_footer_img]][readme_footer_link]
+[![Beacon][beacon]][website]
+
+  [logo]: https://cloudposse.com/logo-300x69.svg
+  [docs]: https://cpco.io/docs
+  [website]: https://cpco.io/homepage
+  [github]: https://cpco.io/github
+  [jobs]: https://cpco.io/jobs
+  [hire]: https://cpco.io/hire
+  [slack]: https://cpco.io/slack
+  [linkedin]: https://cpco.io/linkedin
+  [twitter]: https://cpco.io/twitter
+  [testimonial]: https://cpco.io/leave-testimonial
+  [newsletter]: https://cpco.io/newsletter
+  [email]: https://cpco.io/email
+  [commercial_support]: https://cpco.io/commercial-support
+  [we_love_open_source]: https://cpco.io/we-love-open-source
+  [module_development]: https://cpco.io/module-development
+  [terraform_modules]: https://cpco.io/terraform-modules
+  [readme_header_img]: https://cloudposse.com/readme/header/img?repo=cloudposse/terraform-aws-elasticache-redis
+  [readme_header_link]: https://cloudposse.com/readme/header/link?repo=cloudposse/terraform-aws-elasticache-redis
+  [readme_footer_img]: https://cloudposse.com/readme/footer/img?repo=cloudposse/terraform-aws-elasticache-redis
+  [readme_footer_link]: https://cloudposse.com/readme/footer/link?repo=cloudposse/terraform-aws-elasticache-redis
+  [readme_commercial_support_img]: https://cloudposse.com/readme/commercial-support/img?repo=cloudposse/terraform-aws-elasticache-redis
+  [readme_commercial_support_link]: https://cloudposse.com/readme/commercial-support/link?repo=cloudposse/terraform-aws-elasticache-redis
+  [share_twitter]: https://twitter.com/intent/tweet/?text=terraform-aws-elasticache-redis&url=https://github.com/cloudposse/terraform-aws-elasticache-redis
+  [share_linkedin]: https://www.linkedin.com/shareArticle?mini=true&title=terraform-aws-elasticache-redis&url=https://github.com/cloudposse/terraform-aws-elasticache-redis
+  [share_reddit]: https://reddit.com/submit/?url=https://github.com/cloudposse/terraform-aws-elasticache-redis
+  [share_facebook]: https://facebook.com/sharer/sharer.php?u=https://github.com/cloudposse/terraform-aws-elasticache-redis
+  [share_googleplus]: https://plus.google.com/share?url=https://github.com/cloudposse/terraform-aws-elasticache-redis
+  [share_email]: mailto:?subject=terraform-aws-elasticache-redis&body=https://github.com/cloudposse/terraform-aws-elasticache-redis
+  [beacon]: https://ga-beacon.cloudposse.com/UA-76589703-4/cloudposse/terraform-aws-elasticache-redis?pixel&cs=github&cm=readme&an=terraform-aws-elasticache-redis

docs/terraform.md

@@ -24,6 +24,7 @@
 | notification_topic_arn | Notification topic arn | string | `` | no |
 | parameter | A list of Redis parameters to apply. Note that parameters may differ from one Redis family to another | list | `<list>` | no |
 | port | Redis port | string | `6379` | no |
+| replication_group_id | Replication group ID with the following constraints:  A name must contain from 1 to 20 alphanumeric characters or hyphens.   The first character must be a letter.   A name cannot end with a hyphen or contain two consecutive hyphens. | string | `` | no |
 | security_groups | AWS security group ids | list | `<list>` | no |
 | stage | Stage | string | `default` | no |
 | subnets | AWS subnet ids | list | `<list>` | no |

main.tf

@@ -52,7 +52,7 @@ resource "aws_elasticache_replication_group" "default" {
   count = "${var.enabled == "true" ? 1 : 0}"
 
   auth_token                    = "${var.auth_token}"
-  replication_group_id          = "${module.label.id}"
+  replication_group_id          = "${var.replication_group_id == "" ? module.label.id : var.replication_group_id}"
   replication_group_description = "${module.label.id}"
   node_type                     = "${var.instance_type}"
   number_cache_clusters         = "${var.cluster_size}"

variables.tf

@@ -147,3 +147,9 @@ variable "auth_token" {
   description = "Auth token for password protecting redis, transit_encryption_enabled must be set to 'true'! Password must be longer than 16 chars"
   default     = ""
 }
+
+variable "replication_group_id" {
+  type        = "string"
+  description = "Replication group ID with the following constraints: \nA name must contain from 1 to 20 alphanumeric characters or hyphens. \n The first character must be a letter. \n A name cannot end with a hyphen or contain two consecutive hyphens."
+  default     = ""
+}