Muppy Templates

Muppy templates use the Jinja2 engine to dynamically generate configuration files.

Introduction

Templates allow you to:

• Generate systemd configuration files
• Create custom shell scripts
• Produce application configuration files

Template Types

Type	Description
systemd-unit	Systemd unit file (.service)
systemd-timer	Systemd timer file (.timer)
sqlquery	SQL Query
shellscript	Bash/Sh Script
cfgfile	Configuration file

Accessing Templates

Templates are accessible via the Configuration > Templates menu.

Template Upload Wizard

The Template Upload Wizard allows you to render a template and upload it to a remote host.

Accessing the Wizard

1. Go to Configuration > Templates menu
2. Open a template
3. Click the Upload to Host button in the header bar

Wizard Fields

Field	Description	Example
Template	Selected template (read-only)	-
Host	Host where the file will be uploaded	my-server
Target Object	Muppy object injected as obj in the context	mpy.dev_server,123
Target Directory	Destination directory	/etc/systemd/system
Filename	File name	myservice.service
Owner (chown)	File owner	root:root
Permissions (chmod)	File mode	644
Additional Parameters	YAML/JSON parameters merged into context	See below
Run Asynchronously	Execute via message queue	true/false

Template Context

The template automatically receives the following variables:

• obj: The selected target object (if specified)
• template_obj: The template itself
• get_system_parameter(): Function to access Odoo system parameters
• get_system_parameter_json(): Function to access system parameters as JSON
• All parameters defined in "Additional Parameters"

Additional Parameters Example

Parameters can be provided in YAML or JSON format:

# YAML format
service_name: myapp
port: 8080
environment:
  DEBUG: "false"
  LOG_LEVEL: info
users:
  - alice
  - bob

{
  "service_name": "myapp",
  "port": 8080,
  "environment": {
    "DEBUG": "false",
    "LOG_LEVEL": "info"
  },
  "users": ["alice", "bob"]
}

Preview

Preview

Use the Preview tab in the wizard to test the template rendering before uploading it to the server.

The Render Preview button generates the final content without uploading.

Execution Mode

• Synchronous (default): The wizard waits for the upload to complete and displays the result
• Asynchronous: The upload is queued and executed in the background

Asynchronous Mode

Asynchronous mode is recommended for hosts with high network latency or when performing multiple successive uploads.

---

Jinja2 Syntax

Variables

{{ variable }}
{{ obj.field_name }}
{{ obj.related_id.name }}

Conditions

{% if condition %}
  content if true
{% elif other_condition %}
  alternative content
{% else %}
  default content
{% endif %}

Loops

{% for item in list %}
  {{ item }}
{% endfor %}

{% for key, value in dict.items() %}
  {{ key }}: {{ value }}
{% endfor %}

Filters

{{ variable | default('default_value') }}
{{ variable | upper }}
{{ variable | lower }}
{{ list | join(', ') }}

to_yaml Filter

The to_yaml filter is Muppy-specific and converts Python structures to YAML:

{{ my_dict | to_yaml }}

---

Template Examples

Systemd Unit Template

[Unit]
Description={{ obj.description }}
After=network.target
{% if obj.requires %}
Requires={{ obj.requires }}
{% endif %}

[Service]
Type=simple
ExecStart={{ obj.execstart_script }}
{% for key, value in environment.items() %}
Environment="{{ key }}={{ value }}"
{% endfor %}
User={{ obj.user | default('root') }}
WorkingDirectory={{ obj.working_directory | default('/opt') }}
Restart={{ obj.restart | default('on-failure') }}

[Install]
WantedBy=multi-user.target

Shell Script Template

#!/bin/bash
# Auto-generated script
# Date: {{ template_obj.create_date }}

SERVICE_NAME="{{ service_name }}"
PORT="{{ port }}"

echo "Starting $SERVICE_NAME on port $PORT"

{% for cmd in startup_commands %}
{{ cmd }}
{% endfor %}

exit 0

YAML Config Template

# Configuration for {{ obj.name }}
server:
  host: {{ obj.host_id.ip_address }}
  port: {{ port | default(8080) }}

database:
  host: {{ db_host }}
  name: {{ db_name }}
  user: {{ db_user }}

logging:
  level: {{ log_level | default('INFO') }}
  format: "%(asctime)s - %(name)s - %(levelname)s - %(message)s"

---

Best Practices

Template Naming

• Use descriptive codes: myapp-systemd-unit, myapp-config-yaml
• Prefix with the relevant module/application
• Suffix with the generated file type

Context and Variables

• Always provide default values with | default()
• Document expected variables in the template description
• Use obj for dynamic data from the target object

Testing

Before deploying a template:

1. Use the Test tab in the template form
2. Fill in a debug_object_id and debug_context
3. Click Rendering Test to verify the result
4. Use the wizard's Preview with actual parameters

System Templates

Templates marked as is_system = True are protected and should not be modified directly. Create a copy if modifications are needed.