feat: Docker image for installer and installation script improvements (#2)

* Added requirement for md5sum, and fixed check for existance having errors exit the script

* Dockerfile for installer with AZ cli and prerequisites

* Added uninstall script

* Added instructions to use Docker image to install and uninstall

Author: vicenteherrera

Dockerfile

@@ -0,0 +1,13 @@
+FROM mcr.microsoft.com/azure-cli
+
+RUN apk add gettext \
+ && az aks install-cli
+
+WORKDIR /app
+
+COPY ./install-aks-audit-log.sh .
+COPY ./uninstall-aks-audit-log.sh .
+
+WORKDIR /data
+
+ENTRYPOINT [ "/app/install-aks-audit-log.sh" ]

README.md

@@ -6,21 +6,42 @@ This repository contains an installation/uninstallation script, instructions and
 
 ## Installation
 
+You can execute the automatic installation steps using a docker image that has all requirements, or directly using Bash if you already have the requirements in your system.
+
+You need to know the AKS Cluster Name and the Resource Group Name that you used to create your [Azure AKS Cluster](https://docs.microsoft.com/en-us/azure/aks/kubernetes-walkthrough).
+
+### A. Using Docker image installer
+
+To execute the installer using a Docker image and sharing your Azure credentials with it, execute:
+
+```bash
+docker run -it -v $HOME/.azure:/root/.azure sysdiglabs/aks-audit-log-installer:1 \
+  -g YOUR_RESOURCE_GROUP_NAME -c YOUR_AKS_CLUSTER_NAME
+```
+
+To see more optional parameters, use:
+
+```bash
+docker run sysdiglabs/aks-audit-log-installer:1 --help
+```
+
+### B. Using the Bash script
+
 The installation script has some command line tool requirements:
   * [Azure-cli](https://docs.microsoft.com/en-us/cli/azure/install-azure-cli?view=azure-cli-latest) (already logged into your account)
   * envsubst (shipped with gettext package)
   * kubectl
   * curl, tr, grep
 
-You need to know the AKS Cluster Name and the Resource Group Name that you used to create your [Azure AKS Cluster](https://docs.microsoft.com/en-us/azure/aks/kubernetes-walkthrough).
 
 ```bash
 curl -s https://raw.githubusercontent.com/sysdiglabs/aks-audit-log/master/install-aks-audit-log.sh | \
   bash -s -- -g YOUR_RESOURCE_GROUP_NAME -c YOUR_AKS_CLUSTER_NAME
 ```
 
-To see more optional parameters, use
-```
+To see more optional parameters, use:
+
+```bash
 curl -s https://raw.githubusercontent.com/sysdiglabs/aks-audit-log/master/install-aks-audit-log.sh | \
   bash -s -- --help
 ```
@@ -43,6 +64,17 @@ kubectl log aks-audit-log-forwarder-XXXX -f
 
 Use the same parameters as for installation. The script will delete all created resources and configurations.
 
+Using Docker image:
+
+```bash
+docker run -it -v $HOME/.azure:/root/.azure \
+  --entrypoint /app/uninstall-aks-audit-log.sh \
+  sysdiglabs/aks-audit-log-installer:1 \
+  -g YOUR_RESOURCE_GROUP_NAME -c YOUR_AKS_CLUSTER_NAME
+```
+
+Using uninstall Bash script:
+
 ```bash
 curl -s https://raw.githubusercontent.com/sysdiglabs/aks-audit-log/master/uninstall-aks-audit-log.sh | \
   bash -s -- -g YOUR_RESOURCE_GROUP_NAME -c YOUR_AKS_CLUSTER_NAME

install-aks-audit-log.sh

@@ -5,41 +5,46 @@ set -euf
 function check_commands_installed {
     echo "[1/12] Checking requirements"
     local exists
-    exists=$(which az)
+    exists=$(which az ||:)
     if [ "$exists" == "" ]; then
         echo "Required command line tool 'az' not available."
         echo "For instructions on how to install it, visit:"
         ecbo "https://docs.microsoft.com/en-us/cli/azure/install-azure-cli?view=azure-cli-latest"
         exit 1
     fi
-    exists=$(which kubectl)
+    exists=$(which kubectl ||:)
     if [ "$exists" == "" ]; then
         echo "Required command line tool 'kubectl' not available."
         echo "Yoy may install it using:"
         echo "  az aks install-cli"
         exit 1
     fi
-    exists=$(which envsubst)
+    exists=$(which envsubst ||:)
     if [ "$exists" == "" ]; then
         echo "Required command line tool 'envsubts' not available."
         echo "You may find it in the gettext or gettext-base packages."
         exit 1
     fi
-    exists=$(which curl)
+    exists=$(which curl ||:)
     if [ "$exists" == "" ]; then
         echo "Required command line tool 'curl' not available."
         exit 1
     fi
-    exists=$(which tr)
+    exists=$(which tr ||:)
     if [ "$exists" == "" ]; then
         echo "Required command line tool 'tr' not available."
         exit 1
     fi
-    exists=$(which grep)
+    exists=$(which grep ||:)
     if [ "$exists" == "" ]; then
         echo "Required command line tool 'grep' not available."
         exit 1
     fi
+    exists=$(which md5sum ||:)
+    if [ "$exists" == "" ]; then
+        echo "Required command line tool 'md5sum' not available."
+        exit 1
+    fi
 }
 
 function check_cluster {