feat: add Hetzner Cloud server template

.github/typos.toml

@@ -5,6 +5,13 @@ Hashi = "Hashi"
 HashiCorp = "HashiCorp"
 mavrickrishi = "mavrickrishi" # Username
 mavrick = "mavrick" # Username
+melmathari = "melmathari" # Username
+fsn1 = "fsn1" # Hetzner Falkenstein datacenter code
+nbg1 = "nbg1" # Hetzner Nuremberg datacenter code
+hel1 = "hel1" # Hetzner Helsinki datacenter code
+hel = "hel"   # Hetzner Helsinki short code
+hcloud = "hcloud" # Hetzner Cloud CLI/API
+vcpus = "vcpus" # Virtual CPUs
 
 [files]
 extend-exclude = ["registry/coder/templates/aws-devcontainer/architecture.svg"] #False positive

registry/melmathari/README.md

@@ -0,0 +1,16 @@
+---
+display_name: "Mohamed El Mathari"
+bio: "Software engineer, no-code nerd, teacher, and always ready to try something new"
+avatar: "./.images/melmathari.jpeg"
+github: "melmathari"
+linkedin: "https://www.linkedin.com/in/melmathari/"
+website: "https://melmathari.dev"
+support_email: "[email protected]"
+status: community
+---
+
+# About Me
+
+👨‍💻 Learning by contributing in Open Source.
+
+Software engineer, no-code nerd, teacher, and always ready to try something new. Based in the Netherlands, I'm a no-code advocate who loves building tools and launching products that make a difference. Whether I'm coding, mentoring, or experimenting, I aim to keep things simple and impactful. I'm a big fan of breaking down complex problems into straightforward solutions—one idea at a time.

registry/melmathari/templates/hetzner-cloud/README.md

@@ -0,0 +1,263 @@
+---
+display_name: Hetzner Cloud Server (Linux)
+description: Provision Hetzner Cloud servers as Coder workspaces with networking and volumes
+icon: ../../../../.icons/hetzner.svg
+verified: false
+tags: [vm, linux, hetzner, cloud, germany]
+---
+
+# Remote Development on Hetzner Cloud
+
+Provision Hetzner Cloud servers as [Coder workspaces](https://coder.com/docs/workspaces) with this template.
+
+This template provides a comprehensive Hetzner Cloud setup with:
+
+- **Dynamic Configuration**: Server types, locations, and images loaded from JSON
+- **Location-Aware Filtering**: Available server types automatically filter based on selected location
+- **Multiple Server Types**: ARM, Intel, AMD shared, and dedicated instances
+- **Global Locations**: Europe, USA, and Asia datacenters
+- **Persistent Storage**: Home volumes that survive workspace restarts
+- **Secure Networking**: Private networks with firewall rules
+- **Clean Architecture**: Region-based availability in JSON for easy maintenance
+
+## Prerequisites
+
+To deploy workspaces as Hetzner Cloud servers, you'll need:
+
+- Hetzner Cloud [API token](https://docs.hetzner.cloud/#authentication)
+- Hetzner Cloud project (create one in the [Hetzner Cloud Console](https://console.hetzner.cloud/))
+- **SSH Keys**: Upload your SSH public keys to your Hetzner Cloud account (the template will use all available keys)
+
+### Authentication
+
+This template assumes that the Coder Provisioner is run in an environment that is authenticated with Hetzner Cloud.
+
+Set the `HCLOUD_TOKEN` environment variable to your Hetzner Cloud API token, or provide it via the `hcloud_token` variable in your `terraform.tfvars` file.
+
+For other authentication methods, consult the [Hetzner Cloud Terraform provider documentation](https://registry.terraform.io/providers/hetznercloud/hcloud/latest/docs).
+
+### Image Name Verification
+
+The template uses Hetzner's official image names. To verify current available images:
+
+```bash
+# Set your API token
+export HCLOUD_TOKEN="your-hetzner-cloud-api-token"
+
+# List all available images
+curl -s -H "Authorization: Bearer $HCLOUD_TOKEN" \
+  "https://api.hetzner.cloud/v1/images" \
+  | jq '.images[] | select(.type=="system") | .name'
+```
+
+If you encounter image-related errors, check that the image names in `hetzner-config.json` match the official names exactly (some may include architecture suffixes like `-amd64`).
+
+## Architecture
+
+This template provisions the following resources:
+
+- **Hetzner Cloud server** (ephemeral, deleted on workspace stop)
+- **Persistent volume** (mounted to `/home/<username>`, survives workspace restarts)
+- **Private network** with subnet for secure communication
+- **Firewall** with rules for SSH, HTTP, HTTPS, and development ports
+- **SSH keys** automatically loaded from your Hetzner Cloud account
+
+### Lifecycle Management
+
+- **Workspace start**: Server and volume are created, volume is attached
+- **Workspace stop**: Server is destroyed, but volume persists
+- **Workspace restart**: New server is created and existing volume is reattached
+
+This means that when the workspace restarts, any tools or files outside of the home directory are not persisted. To pre-bake tools into the workspace, modify the server image or use a [startup script](https://registry.terraform.io/providers/coder/coder/latest/docs/resources/script).
+
+## Server Types
+
+The template supports multiple Hetzner Cloud server types across four categories:
+
+- **ARM-based (CAX)**: Energy-efficient ARM architecture instances
+- **Intel CPU-Optimized (CPX)**: High-performance Intel processors
+- **AMD Shared (CX)**: Cost-effective AMD shared instances
+- **Dedicated vCPU (CCX)**: Dedicated CPU resources for consistent performance
+
+Server types are automatically filtered based on your selected location. The specific availability is managed in `hetzner-config.json`.
+
+## Locations
+
+Available locations:
+
+- **Falkenstein, Germany** (fsn1) - Europe
+- **Nuremberg, Germany** (nbg1) - Europe
+- **Helsinki, Finland** (hel1) - Europe
+- **Ashburn, Virginia, USA** (ash) - US East Coast
+- **Hillsboro, Oregon, USA** (hil) - US West Coast
+- **Singapore** (sin) - Asia Pacific
+
+## Supported Operating Systems
+
+- Ubuntu 24.04 LTS
+- Ubuntu 22.04 LTS (default)
+- Ubuntu 20.04 LTS
+- Debian 12
+- Debian 11
+- CentOS Stream 9
+- Fedora 39
+- Rocky Linux 9
+- AlmaLinux 9
+
+## Configuration
+
+### Required Variables
+
+```hcl
+# terraform.tfvars
+hcloud_token = "your-hetzner-cloud-api-token"
+```
+
+### Maintaining Configuration
+
+The template uses `hetzner-config.json` for dynamic configuration:
+
+- **Server Types**: Add new server types with their specifications
+- **Locations**: Add new Hetzner datacenters as they become available
+- **Images**: Update with current Hetzner image names (verify with API)
+- **Availability**: Map server type restrictions per location (only shown server types that are available)
+
+**How it works**: When a user selects a location, the template automatically filters the server type dropdown to only show instances available in that location. This prevents configuration errors by design.
+
+**Example**: Adding a new server type:
+
+```json
+"cx62": { "name": "CX62 (16 vCPU, 64 GB RAM, AMD)", "vcpus": 16, "memory": 64 }
+```
+
+The `availability_by_location` section maps which server types are available in each region:
+
+```json
+"availability_by_location": {
+  "fsn1": ["cax11", "cpx11", "cx22", "ccx13", ...],  // Europe: All types
+  "ash": ["cpx11", "ccx13", ...],                     // USA: Intel + Dedicated only
+  "sin": ["cpx11", "ccx13", ...]                      // Asia: Intel + Dedicated only
+}
+```
+
+**Important**: Always verify image names match Hetzner's official names exactly to avoid provisioning errors.
+
+### Optional Variables
+
+All other parameters can be configured through the Coder workspace creation interface:
+
+- **Location**: Choose the datacenter location
+- **Server Type**: Select from available server configurations
+- **Operating System**: Choose your preferred Linux distribution from the curated list
+- **Custom Image Override**: Optionally specify a custom Hetzner Cloud image name (overrides the OS selection)
+- **Home Volume Size**: Set the size of persistent storage (10-1000 GB)
+
+### Custom Images
+
+You can use custom images in two ways:
+
+1. **Override Field**: Leave the "Custom Image Override" field empty to use the selected OS, or enter a custom image name to override it
+2. **Examples**:
+   - `my-custom-snapshot` - Your own Hetzner Cloud snapshot
+   - `debian-12-amd64` - Specific architecture variant
+   - `ubuntu-24.04` - Newer image not yet in the dropdown list
+
+The custom override takes precedence over the dropdown selection, allowing you to use any valid Hetzner Cloud image name.
+
+## Security
+
+The template includes:
+
+- Private networking for secure inter-service communication
+- Firewall rules allowing only necessary ports (22, 80, 443, 8080)
+- SSH key authentication
+- User isolation through cloud-init configuration
+
+## Cost Optimization
+
+- Servers are destroyed when workspaces stop, minimizing compute costs
+- Volumes persist but are only charged for storage when servers are stopped
+- Choose appropriate server types based on workload requirements
+- Consider using shared vCPU instances for development workloads
+
+## Troubleshooting
+
+### Server Type Options Change When Selecting Location
+
+This is expected behavior! The template dynamically filters server types based on regional availability:
+
+- **Europe (fsn1, nbg1, hel1)**: Shows all server types including ARM (CAX) and AMD (CX)
+- **USA/Asia (ash, hil, sin)**: Shows only Intel (CPX) and Dedicated (CCX) servers
+
+This prevents configuration errors by only showing what's actually available in your selected region.
+
+### Image Not Found Errors
+
+If you get errors like "image not found" or "invalid image name":
+
+1. **Verify Image Names**: Check current available images using the API:
+
+   ```bash
+   curl -s -H "Authorization: Bearer $HCLOUD_TOKEN" \
+     "https://api.hetzner.cloud/v1/images" \
+     | jq '.images[] | select(.type=="system") | .name' | sort
+   ```
+
+2. **Update JSON Configuration**: Edit `hetzner-config.json` to match exact image names from Hetzner
+3. **Common Issues**:
+   - Some images may have architecture suffixes (e.g., `debian-12` vs `debian-12-amd64`)
+   - Image names may change over time as new versions are released
+   - Deprecated images are removed from the available list
+
+4. **Test Locally**: Before using in Coder, test image names with basic Terraform:
+   ```hcl
+   resource "hcloud_server" "test" {
+     name        = "test"
+     server_type = "cx11"
+     image       = "ubuntu-22.04"  # Test this image name
+     location    = "fsn1"
+   }
+   ```
+
+### Volume Mount Issues
+
+If the home directory doesn't mount properly:
+
+1. Check that the volume is attached to the server
+2. Verify the cloud-init configuration is applied correctly
+3. Ensure the filesystem is formatted as ext4
+
+### Network Connectivity Issues
+
+If you can't connect to development servers:
+
+1. Verify firewall rules allow the required ports
+2. Check that the private network is configured correctly
+3. Ensure the server has a public IP address
+
+## Local Testing
+
+To test this template locally, create a `terraform.tfvars` file with:
+
+```hcl
+hcloud_token = "your-hetzner-cloud-api-token"
+```
+
+Then run:
+
+```bash
+terraform init
+terraform validate
+terraform plan
+```
+
+## Notes
+
+> [!NOTE]
+> This template is designed to be a starting point! Edit the Terraform configuration to extend the template to support your specific use case.
+
+> [!IMPORTANT]
+> The SSH key parameter defaults to 0 (no SSH key). To enable SSH access, set `ssh_key_id` to your actual SSH key ID from Hetzner Cloud.
+
+> [!WARNING]
+> Server types are automatically filtered based on location availability. If you don't see a specific server type in the dropdown, it's not available in your selected location.

registry/melmathari/templates/hetzner-cloud/cloud-config.yaml.tftpl

@@ -0,0 +1,57 @@
+#cloud-config
+hostname: ${hostname}
+users:
+  - name: ${username}
+    sudo: ["ALL=(ALL) NOPASSWD:ALL"]
+    groups: sudo
+    shell: /bin/bash
+packages:
+  - git
+  - curl
+  - wget
+  - unzip
+  - htop
+disk_setup:
+  ${volume_device}:
+    table_type: "gpt"
+    layout: true
+    overwrite: false
+fs_setup:
+  - label: coder-home
+    filesystem: ext4
+    device: ${volume_device}
+    partition: auto
+mounts:
+  - ["${volume_device}", "/home/${username}", "ext4", "defaults", "0", "2"]
+write_files:
+  - path: /opt/coder/init
+    permissions: "0755"
+    encoding: b64
+    content: ${init_script}
+  - path: /etc/systemd/system/coder-agent.service
+    permissions: "0644"
+    content: |
+      [Unit]
+      Description=Coder Agent
+      After=network-online.target
+      Wants=network-online.target
+
+      [Service]
+      User=${username}
+      ExecStart=/opt/coder/init
+      Environment=CODER_AGENT_TOKEN=${coder_agent_token}
+      Restart=always
+      RestartSec=10
+      TimeoutStopSec=90
+      KillMode=process
+
+      OOMScoreAdjust=-1000
+      SyslogIdentifier=coder-agent
+
+      [Install]
+      WantedBy=multi-user.target
+runcmd:
+  - mkdir -p /home/${username}
+  - chown ${username}:${username} /home/${username}
+  - systemctl enable coder-agent
+  - systemctl start coder-agent