feat: Add interactive packer build script

This commit implements comprehensive SSH/SCP compatibility fixes and
creates an interactive build script for Jenkins Job Builder (JJB)
validated Packer image combinations. Make life easy for maintainers
to run manual builds at times when new base images need to be uploaded
and built manually allowing simultanous builds.

- templates/builder.pkr.hcl
- templates/builder-aws.pkr.hcl
- templates/docker.pkr.hcl
- templates/docker-aws.pkr.hcl
- templates/devstack.pkr.hcl
- templates/devstack-pre-pip-yoga.pkr.hcl
- templates/windows-builder.pkr.hcl

1. **Added local_build variable**: Controls SSH compatibility mode
- Type: bool, default: false
- Description: "Set to true for local builds to enable SSH/scp
  compatibility"

2. **Added conditional SSH arguments**: Using HCL ternary expressions
- For local builds (local_build=true):
* `--scp-extra-args "'-O'"` - Fixes SCP upload failures
* Enhanced SSH algorithms including PubkeyAcceptedAlgorithms=+ssh-rsa
- For CI builds (local_build=false): Standard SSH arguments

3. **Updated ansible provisioner**: Replaced hardcoded extra_arguments
with dynamic `local.ssh_extra_args`

4. **Preserved existing functionality**: DevStack yoga templates
maintain existing extra-vars while adding SSH compatibility

- **JJB Integration**: Reads supported combinations from
  releng-packer-jobs.yaml
- **EOL Platform Exclusion**: Automatically excludes ubuntu-18.04 EOL
- **21 Validated Combinations**: Only builds JJB-approved
  platform+template pairs
- **Comprehensive Logging**: Individual timestamped log files per
  build in /tmp/
- **Execution Modes**: Interactive, dry-run, and background build
  options
- **Auto SSH Compatibility**: Automatically sets local_build=true for
  all builds

- Smart file discovery and validation
- User-friendly numbered menus
- Real-time build progress tracking
- Proper relative path handling
- Background process management
- Build status reporting with exit codes

- Complete usage instructions for JJB-based builds
- Prerequisites and environment setup guide
- All 21 JJB combination listings by image type
- Example usage scenarios
- Troubleshooting section with common issues
- Comprehensive logging and monitoring documentation

This addresses critical SSH/SCP compatibility issues that were causing
Packer builds to fail with errors like:
scp: dest open "'~user/.ansible/tmp/...": No such file or directory

The conditional approach allows:
- **Local Development**: Enhanced SSH compatibility when local_build=true
- **CI/CD Compatibility**: Preserved existing behavior when local_build=false
- **Maintainability**: Centralized SSH logic in reusable locals blocks

Validated against Jenkins Job Builder configuration ensuring only
approved platform/template combinations are built, improving build
reliability and reducing maintenance overhead.

Change-Id: I0ff854c63c96d97e98f8b5f436195c7af91fea36
Signed-off-by: Anil Belur <abelur@linuxfoundation.org>

Author: askb

README.md

@@ -0,0 +1,296 @@
+# Packer Image Builder Script
+
+This repository contains an interactive script for building packer images using
+Jenkins Job Builder (JJB) validated combinations, excluding End-of-Life platforms.
+
+## Prerequisites
+
+### 1. Environment Setup
+
+Before running any packer builds, you must configure your environment:
+Ensure the latest version of the ci-management repository is cloned on
+a host with the cloud tenant access. If you are running this locally
+ensure you have a loopback ssh tunnel to the bastion host (IP address of
+the Jenkins sandbox) on a separate terminal.
+
+```bash
+# Set Python version using pyenv
+pyenv global 3.10.13
+
+# Activate ansible virtual environment
+source ~/virtualenv/ansible/bin/activate
+
+# Verify setup
+python --version  # Should show Python 3.10.13
+which python      # Should show pyenv path
+```
+
+### 2. Required Files
+
+Ensure these files exist in the parent directory:
+
+- `cloud-env.json` - OpenStack cloud configuration
+- `OS_CLOUD` environment variable set to `odlci`
+- `.config/openstack/clouds.yaml` - OpenStack credentials
+
+### 3. Directory Structure
+
+The script expects this structure:
+
+```
+ci-management/                         # Repository root
+├── jjb/
+│   └── releng-packer-jobs.yaml  # JJB configuration (validates combinations)
+├── packer/
+│   ├── common-packer/           # This directory
+│   │   ├── build-packer-images.sh  # Interactive JJB script
+│   │   ├── vars/                # Variable files
+│   │   │   ├── ubuntu-22.04.pkrvars.hcl
+│   │   │   ├── ubuntu-24.04.pkrvars.hcl
+│   │   │   └── ...
+│   │   └── templates/           # Common templates
+│   │       ├── builder.pkr.hcl
+│   │       ├── docker.pkr.hcl
+│   │       └── ...
+│   └── templates/               # Additional templates
+│       ├── devstack.pkr.hcl
+│       ├── robot.pkr.hcl
+│       └── ...
+└── cloud-env.json               # OpenStack cloud configuration
+```
+
+## Usage
+
+### Interactive JJB Script (Recommended)
+
+1. **Navigate to the repository root:**
+
+   ```bash
+   cd builder
+   ```
+
+2. **Run the JJB-based interactive script:**
+
+   ```bash
+   ./packer/common-packer/build-packer-images.sh
+   ```
+
+3. **Follow the prompts:**
+   - **Option 1**: Build all JJB combinations (21 validated builds, ubuntu-18.04 EOL excluded)
+   - **Option 2**: Select specific combinations by number
+   - **Option 3**: Exit
+
+4. **Choose execution mode:**
+   - **Mode 1**: Execute builds immediately (sequential) with live output + log files
+   - **Mode 2**: Generate build commands only (dry-run)
+   - **Mode 3**: Execute builds in background (parallel) with individual log files
+
+### JJB Validated Combinations (21 total)
+
+The script only builds combinations validated in `jjb/releng-packer-jobs.yaml`:
+
+**Builder images (6 platforms):**
+
+- centos-7, centos-cs-8, centos-cs-9, ubuntu-20.04, ubuntu-22.04, ubuntu-24.04
+
+**Docker images (3 platforms, ubuntu-18.04 EOL excluded):**
+
+- centos-7, ubuntu-20.04, ubuntu-22.04
+
+**DevStack variants (centos-7 only):**
+
+- devstack, devstack-pre-pip-queens, devstack-pre-pip-rocky, devstack-pre-pip-stein
+
+**Specialized images:**
+
+- helm (centos-7)
+- mininet-ovs-217 (ubuntu-22.04, ubuntu-24.04)
+- robot (centos-7, centos-cs-8, centos-cs-9, ubuntu-22.04, ubuntu-24.04)
+
+### Direct Command Line
+
+For individual builds, use this format:
+
+```bash
+# Set environment first
+pyenv global 3.10.13
+source ~/virtualenv/ansible-new/bin/activate
+
+# Run packer build
+OS_CLOUD=odlci packer.io build \
+  -only=openstack.<template-name> \
+  -var-file=cloud-env.json \
+  -var-file=common-packer/vars/<var-file>.pkrvars.hcl \
+  templates/<template-file>.pkr.hcl
+```
+
+#### Build Target Examples:
+
+- Builder: `-only=openstack.builder`
+- Docker: `-only=openstack.docker`
+- Devstack: `-only=openstack.devstack`
+- Robot: `-only=openstack.robot`
+- Helm: `-only=openstack.helm`
+
+## Available Configurations
+
+### Variable Files (OS/Architecture)
+
+- `centos-7.pkrvars.hcl`, `centos-7-arm64.pkrvars.hcl`
+- `centos-8.pkrvars.hcl`
+- `centos-cs-8.pkrvars.hcl`, `centos-cs-9.pkrvars.hcl`
+- `ubuntu-16.04.pkrvars.hcl`, `ubuntu-16.04-arm64.pkrvars.hcl`
+- `ubuntu-18.04.pkrvars.hcl`, `ubuntu-18.04-arm64.pkrvars.hcl`
+- `ubuntu-20.04.pkrvars.hcl`, `ubuntu-20.04-arm64.pkrvars.hcl`
+- `ubuntu-22.04.pkrvars.hcl`
+- `ubuntu-24.04.pkrvars.hcl`, `ubuntu-24.04-arm64.pkrvars.hcl`
+- `windows-server-2016.pkrvars.hcl`
+
+### Template Files (Image Types)
+
+- `builder.pkr.hcl` - Basic builder image
+- `docker.pkr.hcl` - Docker-enabled image
+- `devstack.pkr.hcl` - OpenStack DevStack image
+- `helm.pkr.hcl` - Kubernetes Helm image
+- `robot.pkr.hcl` - Robot Framework testing image
+- `mininet-ovs-217.pkr.hcl` - Mininet networking image
+- Various devstack pre-pip templates
+
+## Example Usage Scenarios
+
+### Scenario 1: Test Single Configuration
+
+```bash
+cd /home/abelur/git/builder
+./packer/common-packer/build-packer-images.sh
+# Choose: 2 (select specific combinations)
+# Enter: 15 (ubuntu-22.04 + builder)
+# Choose: 2 (dry-run mode)
+```
+
+### Scenario 2: Build All Ubuntu Builder Images
+
+```bash
+cd /home/abelur/git/builder
+./packer/common-packer/build-packer-images.sh
+# Choose: 2 (select specific combinations)
+# Enter: 13 15 7 (ubuntu-20.04, ubuntu-22.04, ubuntu-24.04 + builder)
+# Choose: 3 (execute in background)
+```
+
+### Scenario 3: Build All JJB Combinations
+
+```bash
+cd /home/abelur/git/builder
+./packer/common-packer/build-packer-images.sh
+# Choose: 1 (build all 21 JJB combinations)
+# Choose: 3 (execute in background)
+```
+
+## Build Process
+
+Each packer build follows this process:
+
+1. **Environment Setup**: Creates OpenStack instance with specified OS
+2. **Python Installation**: Installs Python and configures package mirrors
+3. **Ansible Setup**: Creates virtual environment and installs Ansible roles
+4. **Provisioning**: Runs Ansible playbooks to configure the image
+5. **Image Creation**: Snapshots the configured instance as a reusable image
+
+## Troubleshooting
+
+### Common Issues
+
+1. **Python 3.10 not found**
+
+   ```bash
+   # Solution: Set pyenv before running builds
+   pyenv global 3.10.13
+   ```
+
+2. **Ansible virtual environment missing**
+
+   ```bash
+   # Solution: Activate ansible venv
+   source ~/virtualenv/ansible-new/bin/activate
+   ```
+
+3. **netselect download failures**
+   - The script automatically handles version compatibility
+   - Ubuntu ≤ 20.04 uses older netselect version
+   - Ubuntu > 20.04 uses newer version
+
+4. **Wrong build target**
+   - The script automatically determines correct targets
+   - Manual commands: use `-only=openstack.<template-basename>`
+
+5. **Cloud configuration issues**
+   ```bash
+   # Verify cloud-env.json exists and OS_CLOUD is set
+   ls -la ../cloud-env.json
+   echo $OS_CLOUD  # Should show: odlci
+   ```
+
+### Network Issues
+
+If ansible-galaxy role downloads fail:
+
+- Check network connectivity
+- Retry the build - temporary network issues often resolve
+- Use `--ignore-errors` flag in ansible-galaxy calls if needed
+
+## Performance Tips
+
+- **Parallel builds**: Use background execution mode for multiple builds
+- **Selective building**: Use dry-run mode first to verify commands
+- **Resource limits**: Monitor OpenStack quota when running many parallel builds
+- **Build time**: Each build takes 15-45 minutes depending on complexity
+
+## Build Output and Logging
+
+### Log Files
+
+All builds are automatically logged to `/tmp/` with detailed filenames:
+
+- **Format**: `/tmp/packer-build-{platform}-{template}-{timestamp}.log`
+- **Examples**:
+  - `/tmp/packer-build-ubuntu-22.04-builder-20250912-143022.log`
+  - `/tmp/packer-build-centos-7-docker-20250912-143055.log`
+- **Contents**: Complete packer output, Ansible logs, error details
+
+### Build Monitoring
+
+- **Sequential mode (1)**: Live output + log files using `tee`
+- **Background mode (3)**: Monitor with `tail -f /tmp/packer-build-*.log`
+- **Status check**: Use `jobs` and `wait` commands
+
+Successful builds create:
+
+- **OpenStack Images**: Registered in the OpenStack image service
+- **Build Logs**: Complete execution logs in `/tmp/`
+- **Ansible Details**: Provisioning steps and configuration changes
+
+Failed builds:
+
+- **Error Logs**: Detailed failure information in log files
+- **Cleanup**: Automatically clean up temporary resources
+- **Retry**: Can be safely retried after fixing issues
+
+## Script Features
+
+- **Auto-discovery**: Finds all variable and template files automatically
+- **Smart filtering**: Excludes configuration files (cloud-env.\*)
+- **Interactive selection**: User-friendly numbered menus
+- **Flexible execution**: Immediate, dry-run, or background modes
+- **Path handling**: Works with any repository name/structure
+- **Error handling**: Validates inputs and file existence
+- **Progress tracking**: Clear indication of build progress
+
+## Support
+
+For issues:
+
+1. Check the troubleshooting section above
+2. Verify all prerequisites are met
+3. Use dry-run mode to validate commands
+4. Review packer and ansible logs for specific errors