Add a build argument for specifying the Packer version

Set default version to `latest`

Using the Docker Action build argument workaround suggested from:
  https://github.community/t/feature-request-build-args-support-in-docker-container-actions/16846/6

Dockerfile

@@ -1,10 +1,14 @@
-FROM hashicorp/packer:1.6.4
+FROM alpine:latest
 
 LABEL "com.github.actions.name" = "Packer AMI Builder"
 LABEL "com.github.actions.description" = "Use GitHub Action to execute Packer AMI build"
 LABEL "com.github.actions.color"="blue"
 LABEL "com.github.actions.icon"="anchor"
 
+COPY docker-action /docker-action
 COPY entrypoint.sh /entrypoint.sh
 RUN chmod +x /entrypoint.sh
+
+RUN apk add --update --no-cache docker
+
 ENTRYPOINT ["/entrypoint.sh"]

README.md

@@ -1,16 +1,21 @@
 # Packer AMI Builder
+
 Use GitHub Action to execute Packer build commands. This supports both HCL and
 JSON packer template files.
 
 For HCL Mode, set `packerArgs` to `build .` to load all `.pkr.hcl` files within
 the dir. To use the override variable file, set `packerArgs` to
 `build -var-file=overrides.pkrvars.hcl`
 
+You can also use `packerVersion` to specify the Packer release you would like
+to use.
+
 ## Input Parameters
-| Name         | Description                                              | Mandatory | Default |
-| ------------ | -------------------------------------------------------- | --------- | ------- |
-| `packerArgs` | Arguments that will be passed down to the packer command | Yes       |         |
-| `workDir`    | Working directory inside the container                   | No        | `.`     |
+| Name            | Description                                              | Mandatory | Default  |
+| --------------- | -------------------------------------------------------- | --------- | -------- |
+| `packerVersion` | Version of Packer will be used                           | No        | `latest` |
+| `packerArgs`    | Arguments that will be passed down to the packer command | Yes       |          |
+| `workDir`       | Working directory inside the container                   | No        | `.`      |
 
 ## Example
 Create a workflow file (e.g `.github/workflows/ami-build.yaml`) like below:
@@ -30,6 +35,7 @@ jobs:
       - name: Packer AMI Build
         uses: zmingxie/packer-ami-builder@master
         with:
+          packerVersion: '1.6.4'
           packerArgs: 'build template.json'
           workDir: '.'
         env:

action.yml

@@ -6,6 +6,10 @@ branding:
   icon: 'anchor'
 
 inputs:
+  packerVersion:
+    description: 'Version of Packer will be used'
+    required: false
+    default: 'latest'
   packerArgs:
     description: 'Arguments that will be passed down to the packer command'
     required: true
@@ -16,3 +20,5 @@ inputs:
 runs:
   using: 'docker'
   image: 'Dockerfile'
+  args:
+    - ${{ inputs.packerVersion }}

docker-action/Dockerfile

@@ -0,0 +1,6 @@
+ARG packer_version
+FROM hashicorp/packer:${packer_version}
+
+COPY entrypoint.sh /entrypoint.sh
+RUN chmod +x /entrypoint.sh
+ENTRYPOINT ["/entrypoint.sh"]

docker-action/entrypoint.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+set -e
+
+cd "${INPUT_WORKDIR:-.}"
+
+# Show Packer version
+packer version
+
+# Run packer with the given arguments
+packer ${INPUT_PACKERARGS}

entrypoint.sh

@@ -1,7 +1,19 @@
-#!/bin/bash
-set -ex
+#!/bin/sh
 
-cd "${INPUT_WORKDIR:-.}"
+PACKER_VERSION=$1
 
-# Run packer with the given arguments
-packer ${INPUT_PACKERARGS}
+# The repo source code is cloned to $RUNNER_WORKSPACE/$REPO_NAME
+# Setup the workspace path to that for easier access later
+REPO_NAME=$(basename $RUNNER_WORKSPACE)
+WS_PATH=$RUNNER_WORKSPACE/$REPO_NAME
+
+cd /docker-action
+
+echo "Creating a docker image with Packer version: $PACKER_VERSION"
+docker build -t docker-action --build-arg packer_version="$PACKER_VERSION" .
+
+echo "Run Docker Action container"
+docker run -e AWS_ACCESS_KEY_ID -e AWS_SECRET_ACCESS_KEY -e AWS_DEFAULT_REGION \
+  -e INPUT_PACKERARGS -e INPUT_PACKERVERSION -e INPUT_WORKDIR  \
+  -v $WS_PATH:$GITHUB_WORKSPACE \
+  --workdir $GITHUB_WORKSPACE docker-action