Add GitLab Instruction doc

README.md

@@ -108,7 +108,7 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v2
 
-    # Step 2: use the versioned sensu/sensuflow action 
+    # Step 2: use the versioned sensu/sensu-flow action 
     - name: Sensuflow with required settings
       uses: sensu/[email protected]
       with:
@@ -260,9 +260,14 @@ _OR_
     description: Optional boolean argument to to disable sanity checks  default: false    
 
 
-## Adapting to Other CI/CD Workflows
-If you would like to adapt this for other CI/CD workflows, take a look at the sensuflow.sh script from this repositorory. The script should be self-documenting with regard to needed executable dependancies and information concerning environment variables used.
+## Using the Docker container image with other CI/CD tools
+While this is originally developed and tested for use with GitHub Actions, there is a vendor neutral `sensu/sensu-flow` [Docker](https://hub.docker.com/repository/docker/sensu/sensu-flow) container image available as of version `0.6.0` that should be suitable for use with any CI/CD tool chain that is capable of using container images for CI/CD jobs. Here's a list of contributed instructions for alternative CI/CD vendors: 
 
+
+* [GitLab](docs/GITLAB.md)
+
+Contributed instructions for additional CI/CD services are welcome.
+
 ## Goals 
 
 SensuFlow is under active development, so please don't hesitate to submit issues for any enhancements you'd like to see. 

docs/GITLAB.md

@@ -0,0 +1,50 @@
+## GitLab
+You can use the `sensu/sensu-flow` [Docker container image](https://docs.gitlab.com/ee/ci/docker/using_docker_images.html#define-image-in-the-gitlab-ciyml-file) with GitLab. This container image includes everything needed to run the `sensuflow.sh` script originally developed for GitHub actions. Please note, it's a good idea to use GitLab's support for [Vault Secrets](https://docs.gitlab.com/ee/ci/yaml/index.html#secrets) for sensitive authentication variables such as the Sensu api key or password.
+
+### Important environment variables
+When using the docker image with GitLab, you'll need to be aware of several environment variables used by the `sensuflow.sh` script run within the Docker container. These variables are documented in the `sensuflow.sh` header comments, but here's a quick summary for reference.
+
+```
+## Required Environment Variables
+# SENSU_API_URL: sensu backend api url used by sensuctl
+# SENSU_API_KEY: sensu api key for sensuctl, used instead of user and password above
+## Optional Environment Variables
+# SENSU_CA: CA certificate as a string
+# SENSU_CA_FILE: CA certificate file, if set overrides SENSU_CA
+# CONFIGURE_OPTIONS: Additional sensuctl configure options
+# NAMESPACES_DIR: directory holding sensuflow namepace subdirectories
+# NAMESPACES_FILE: file holding namespace resource definitions sensuflow action should create
+# MANAGED_RESOURCES: comma seperated list of resources
+# MATCHING_LABEL: resource label to match
+# MATCHING_CONDITION: condition to match
+# DISABLE_SANITY_CHECKS: if set disable sanity checks
+# DISABLE_TLS_VERIFY: if set disable TLS verification 
+## Deprecated Authentication Environment Variables
+# SENSU_USER: sensu user for sensuctl configue (deprecated, use SENSU_API_KEY)
+# SENSU_PASSWORD: sensu password for sensuctl configure (deprecated, use SENSU_API_KEY)
+```
+
+### Reference GitLab CI/CD job definition
+Here's a reference example for a GitLab CI/CD job definition making use of the `sensu/sensu-flow` docker image together with an api-key seeded into a vault.
+```
+stages:
+  - deploy
+
+.sensu_flow:
+  image: sensu/sensu-flow:latest
+  variables:
+    MATCHING_CONDITION: "== '$CI_PROJECT_NAME'"
+    SENSU_BACKEND_URL: https://sensu-api.example.com
+  secrets:
+    SENSU_API_KEY:
+      vault: sensu/sensu-flow/api-key
+      file: false
+  script:
+    - /sensuflow.sh
+
+sensu_flow:
+  extends: .sensu_flow
+  stage: deploy
+  variables:
+    VERBOSE: "1"
+```

sensuflow.sh

@@ -8,10 +8,8 @@
 # jq: https://stedolan.github.io/jq/
 #
 ## Required Environment Variables
-# SENSU_USER: sensu user for sensuctl configure
-# SENSU_PASSWORD: sensu password for sensuctl configure
-# SENSU_API_KEY: sensu api key for sensuctl, used instead of user and password above
 # SENSU_API_URL: sensu backend api url used by sensuctl
+# SENSU_API_KEY: sensu api key for sensuctl, used instead of user and password above
 ## Optional Environment Variables
 # SENSU_CA: CA certificate as a string
 # SENSU_CA_FILE: CA certificate file, if set overrides SENSU_CA
@@ -23,6 +21,9 @@
 # MATCHING_CONDITION: condition to match
 # DISABLE_SANITY_CHECKS: if set disable sanity checks
 # DISABLE_TLS_VERIFY: if set disable TLS verification 
+## Deprecated Authentication Environment Variables
+# SENSU_USER: sensu user for sensuctl configue (deprecated, use SENSU_API_KEY)
+# SENSU_PASSWORD: sensu password for sensuctl configure (deprecated, use SENSU_API_KEY)
 
 ## GitHub Action Notes
 # GitHub Actions prefaces variables with INPUT_