Sceptre

https://docs.sceptre-project.org/latest
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### Install Sceptre with pip

Source: https://docs.sceptre-project.org/latest/_sources/docs/install

Installs the Sceptre tool using pip. Assumes Python is installed and recommends using a virtual environment.

```bash
pip install sceptre
```

--------------------------------

### Sceptre Stack Configuration for VPC

Source: https://docs.sceptre-project.org/latest/docs/get_started

Configuration for a Sceptre Stack, linking to the CloudFormation template and providing parameters.

```yaml
template:
path:vpc.yaml
type:file
parameters:
CidrBlock:10.0.0.0/16
```

--------------------------------

### Sceptre StackGroup Configuration

Source: https://docs.sceptre-project.org/latest/docs/get_started

Configuration for a Sceptre StackGroup, specifying the project code and the AWS region for deployment.

```yaml
project_code:sceptre-example
region:eu-west-1
```

--------------------------------

### Sceptre CLI Commands

Source: https://docs.sceptre-project.org/latest/docs/get_started

Common Sceptre commands for managing CloudFormation stacks, including creating, updating, and deleting stacks, as well as meta commands for inspecting stack information.

```bash
sceptre create dev/vpc
sceptre describe dev/vpc
sceptre update dev/vpc
sceptre delete dev/vpc
```

--------------------------------

### Sceptre Configuration Examples

Source: https://docs.sceptre-project.org/latest/_sources/docs/stack_config

Provides examples of Sceptre configuration files, including template paths, parameters, dependencies, and hooks.

```yaml
template:
  path: templates/example.py
  type: file
parameters:
  param_1: value_1
  param_2: value_2
```

```yaml
template:
  path: templates/example.yaml
  type: file
dependencies:
    - dev/vpc.yaml
hooks:
    before_create:
        - !cmd "echo creating..."
    after_create:
        - !cmd "echo created"
```

--------------------------------

### Sceptre Hook File Structure Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/hooks

Illustrates the basic directory structure for a custom Sceptre hook, including the Python module and the setup script.

```bash
custom_hook
  ├── custom_hook.py
  └── setup.py
```

--------------------------------

### Validate Sceptre Installation

Source: https://docs.sceptre-project.org/latest/_sources/docs/install

Validates the Sceptre installation by printing its version number.

```bash
sceptre --version
```

--------------------------------

### Install and Update Sceptre using pip

Source: https://docs.sceptre-project.org/latest/docs/install

Instructions for installing and updating the Sceptre tool using pip, including how to validate the installation by checking the version.

```bash
pip install sceptre
sceptre --version
pip install sceptre -U
```

--------------------------------

### Update Sceptre with pip

Source: https://docs.sceptre-project.org/latest/_sources/docs/install

Updates the Sceptre tool to the latest version using pip.

```bash
pip install sceptre -U
```

--------------------------------

### Sceptre Plan Launch Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/terminology

Demonstrates how to instantiate a SceptrePlan with a SceptreContext and execute a launch command against the defined stacks.

```python
plan = SceptrePlan(context)

responses = plan.launch()
```

--------------------------------

### Sceptre File Template Example

Source: https://docs.sceptre-project.org/latest/docs/stack_config

An example of a Sceptre configuration using a file template with parameters.

```YAML
template:
  path:templates/example.py
  type:file
parameters:
  param_1:value_1
  param_2:value_2

```

--------------------------------

### CloudFormation VPC Template

Source: https://docs.sceptre-project.org/latest/docs/get_started

Defines a CloudFormation template for creating an AWS VPC. It includes a parameter for the CIDR block and outputs the VPC ID.

```yaml
Parameters:
CidrBlock:
Type:String
Resources:
VPC:
Type:'AWS::EC2::VPC'
Properties:
CidrBlock:
Ref:CidrBlock
Outputs:
VpcId:
Value:
Ref:VPC
```

--------------------------------

### Run Sceptre Docker Container

Source: https://docs.sceptre-project.org/latest/_sources/docs/install

Runs the Sceptre Docker container, mounting the current directory as '/project' and AWS configuration to '/root/.aws/'.

```docker
docker run -v $(pwd):/project -v /Users/me/.aws/:/root/.aws/:ro cloudreach/sceptre:latest --help
```

--------------------------------

### Enter Sceptre Docker Container Shell

Source: https://docs.sceptre-project.org/latest/_sources/docs/install

Enters the shell of the Sceptre Docker container, allowing direct execution of sceptre commands for development purposes.

```docker
docker run -ti --entrypoint='' cloudreach:test sh
```

--------------------------------

### Example Command Path Usage

Source: https://docs.sceptre-project.org/latest/_sources/docs/stack_group_config

Illustrates a Sceptre command and how its path components can be accessed in the configuration.

```text
sceptre launch eu-west-1/dev/vpc.yaml
```

--------------------------------

### Pull Sceptre Docker Image

Source: https://docs.sceptre-project.org/latest/_sources/docs/install

Pulls the Sceptre Docker image. Specify the version number or omit it to pull the 'latest' tag.

```docker
docker pull sceptreorg/sceptre:[SCEPTRE_VERSION_NUMBER]
```

--------------------------------

### Comprehensive Sceptre Configuration Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/stack_group_config

A complete example showcasing the usage of user variables, environment variables, command path, and default values within a Sceptre configuration file.

```yaml
profile: {{ var.profile }}
project_code: {{ var.project_code | default("prj") }}
region: {{ command_path.2 }}
template_bucket_name: {{ environment_variable.TEMPLATE_BUCKET_NAME }}
```

--------------------------------

### Create New Sceptre Project

Source: https://docs.sceptre-project.org/latest/_sources/docs/get_started

Command to generate a new Sceptre project with a predefined directory structure. It prompts for a region and project code.

```text
$ sceptre new project my-sceptre-project

   Please enter a region []:
   Please enter a project_code [my-sceptre-project]:
```

--------------------------------

### Example Variable File Content

Source: https://docs.sceptre-project.org/latest/_sources/docs/stack_group_config

Provides an example of the content expected in a Sceptre variable YAML file.

```yaml
profile: <your profile>
```

--------------------------------

### Sceptre Project Layout Example

Source: https://docs.sceptre-project.org/latest/docs/architecture

Example of a Sceptre project layout for application development within an externally defined VPC. It shows the organization of configuration files for different environments and services.

```yaml
-config
- prod
- application
- asg.yaml
- security-group.yaml
- database
- rds.yaml
- security-group.yaml
```

--------------------------------

### Final Project Directory Structure

Source: https://docs.sceptre-project.org/latest/_sources/docs/get_started

The complete directory structure of the Sceptre project after adding the VPC stack configuration and template.

```text
tree
.
├── config
│   ├── config.yaml
│   └── dev
│       ├── config.yaml
│       └── vpc.yaml
└── templates
    └── vpc.yaml
```

--------------------------------

### Sceptre Template Configuration (S3 Example)

Source: https://docs.sceptre-project.org/latest/_sources/docs/stack_config

Example of configuring a template handler in Sceptre, specifically for loading a template from an S3 bucket. This demonstrates the 'template' key with 'type' and 'path' sub-keys.

```yaml
template:
  type: s3
  path: infra-templates/s3/v1/bucket.yaml
parameters:
  <parameter1_name>: "value"
sceptre_user_data:
```

--------------------------------

### Sceptre Directory Structure Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/stack_group_config

Illustrates a cascading configuration file structure for Sceptre projects, showing how general and specific configurations are organized.

```text
.\n└── config
    ├── account-1
    │   ├── config.yaml
    │   └── dev
    │       └── config.yaml
    └── config.yaml
```

--------------------------------

### Sceptre Stack Configuration for VPC

Source: https://docs.sceptre-project.org/latest/_sources/docs/get_started

Configuration file for a specific Sceptre stack, linking to the CloudFormation template and providing parameters.

```yaml
template:
  path: vpc.yaml
  type: file
parameters:
  CidrBlock: 10.0.0.0/16
```

--------------------------------

### Create VPC Stack

Source: https://docs.sceptre-project.org/latest/_sources/docs/get_started

Command to create the VPC stack defined in the Sceptre project. This command should be executed from the project's root directory.

```text
$ sceptre create dev/vpc.yaml
```

--------------------------------

### SceptrePlan Launch Example

Source: https://docs.sceptre-project.org/latest/docs/terminology

Demonstrates how to create a SceptrePlan with a given context and execute the 'launch' command against the project's stacks. This is a fundamental operation for deploying infrastructure using Sceptre.

```Python
plan = SceptrePlan(context)

responses = plan.launch()
```

--------------------------------

### Sceptre Project Initialization Commands

Source: https://docs.sceptre-project.org/latest/docs/cli

Commands for initializing new Sceptre projects and stack groups. Includes creating project folders and configuration files.

```APIDOC
new
  Commands for initialising Sceptre projects.

group
  Creates StackGroup folder in the project and a config.yaml with any required properties.
  param stack_group: Name of the StackGroup directory to create.
  type stack_group: str
  Arguments:
    STACK_GROUP: Required argument

project
  Creates PROJECT_NAME project folder and a config.yaml with any required properties.
  param project_name: The name of the Sceptre Project to create.
  type project_name: str
  Arguments:
    PROJECT_NAME: Required argument
```

--------------------------------

### Custom Resolver Packaging Setup

Source: https://docs.sceptre-project.org/latest/_sources/docs/resolvers

Illustrates the setup.py file configuration for packaging a custom Sceptre resolver. It specifies the entry points for Sceptre to discover and use the custom resolver.

```python
from setuptools import setup

setup(
    name='<custom_resolver_package_name>',
    py_modules=['<custom_resolver_module_name>'],
    entry_points={
        'sceptre.resolvers': [
            '<custom_resolver_command_name> = <custom_resolver_module_namef>:CustomResolver',
        ],
    }
)
```

--------------------------------

### Custom Hook Packaging (setup.py)

Source: https://docs.sceptre-project.org/latest/_sources/docs/hooks

Example setup.py file for packaging a custom Sceptre hook as a Python package, defining the entry point for Sceptre to discover the hook.

```python
from setuptools import setup

setup(
    name='custom_hook_package',
    py_modules=['<custom_hook_module_name>'],
    entry_points={
        'sceptre.hooks': [
            '<custom_hook_command_name> = <custom_hook_module_name>:CustomHook',
        ],
    }
)
```

--------------------------------

### Custom Resolver Packaging with Setuptools

Source: https://docs.sceptre-project.org/latest/docs/resolvers

Shows how to package a custom Sceptre resolver using `setup.py` and `setuptools`. It details the `entry_points` configuration required for Sceptre to discover and use the custom resolver.

```python
fromsetuptoolsimport setup

setup(
    name='<custom_resolver_package_name>',
    py_modules=['<custom_resolver_module_name>'],
    entry_points={
        'sceptre.resolvers': [
            '<custom_resolver_command_name> = <custom_resolver_module_namef>:CustomResolver',
        ],
    }
)
```

--------------------------------

### Sceptre Project Directory Structure

Source: https://docs.sceptre-project.org/latest/_sources/docs/get_started

Illustrates the default directory layout created by 'sceptre new'. Includes config and templates directories for project configuration and CloudFormation templates.

```text
tree
.
my-sceptre-project
    ├── config
    │   └── config.yaml
    └── templates
```

--------------------------------

### Setup and Usage of Custom Template Handler

Source: https://docs.sceptre-project.org/latest/docs/template_handlers

Provides instructions for packaging a custom template handler using setuptools and integrating it into a Sceptre stack configuration file. It shows how to define the entry point and specify the handler type and module.

```python
from setuptools import setup

setup(
    name='<custom_resolver_package_name>',
    py_modules=['<custom_resolver_module_name>'],
    entry_points={
        'sceptre.template_handlers': [
            '<custom_template_handler_type> = <custom_resolver_module_name>:CustomTemplateHandler',
        ],
    }
)
```

```yaml
template:
  type:<custom_template_handler_type>
  <property>:<value>
```

--------------------------------

### Sceptre Cmd Hook - PowerShell Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/hooks

Example of using the `cmd` hook to execute a PowerShell command.

```yaml
hooks:
  before_update:
    - !cmd
        run: Write-Output "Hello, Posh!"
        shell: pwsh
```

--------------------------------

### Create Directories and Files for VPC Stack

Source: https://docs.sceptre-project.org/latest/_sources/docs/get_started

Shell commands to create necessary directories and configuration files for a VPC stack, including template and stack configuration files.

```text
mkdir config/dev
touch config/dev/config.yaml config/dev/vpc.yaml templates/vpc.yaml
```

--------------------------------

### Basic Sceptre Command Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/hooks

A simple example of using the `!cmd` hook to execute a shell command within a Sceptre configuration.

```yaml
!cmd "echo creating..."
!cmd "echo created"
!cmd "echo done"
```

--------------------------------

### Circular Dependency Avoidance Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/stack_group_config

Provides an example project structure to avoid circular dependencies when referencing Sceptre-managed stacks like template buckets or IAM roles.

```yaml
config/
  - config.yaml               # This is the StackGroup Config for your whole project.
  - sceptre-dependencies.yaml # This stack defines your template bucket, iam role, topics, etc...
  - project/                  # You can put all your other stacks in this StackGroup
      - config.yaml           # In this StackGroup Config you can use !stack_output to
                                # reference outputs from sceptre-dependencies.yaml.
      - vpc.yaml              # Put all your other project stacks inside project/
      - other-stack.yaml
```

--------------------------------

### Sceptre Jinja2 Environment Configuration Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/stack_group_config

Provides an example of how to configure the Jinja2 environment for Sceptre stack templating, including extensions, whitespace control, and newline sequences.

```yaml
j2_environment:
   extensions:
      - jinja2.ext.i18n
      - jinja2.ext.do
   lstrip_blocks: True
   trim_blocks: True
   newline_sequence: \n
```

--------------------------------

### Sceptre Configuration with Hooks and Parameters

Source: https://docs.sceptre-project.org/latest/docs/stack_config

A comprehensive Sceptre configuration example demonstrating dependencies, before_create and after_create hooks, various parameter types (stack outputs, environment variables, file contents), and stack tags.

```YAML
template:
  path:templates/example.yaml
  type:file
dependencies:
-dev/vpc.yaml
hooks:
before_create:
-!cmd"echocreating..."
after_create:
-!cmd"echocreated"
-!cmd"echodone"
after_update:
-!cmd"mkdirexample"
-!cmd"touchexample.txt"
parameters:
  param_1:!stack_outputstack_name.yaml::output_name
  param_2:!stack_outputexternalfull_stack_name::output_name
  param_3:!environment_variableVALUE_3
  param_4:
{{var.value4}}
  param_5:
{{command_path.3}}
  param_6:
{{environment_variable.VALUE_6}}
sceptre_user_data:
  thing_1:value_1
  thing_2:!file_contentspath/to/file.txt
stack_tags:
  tag_1:value_1
  tag_2:value_2

```

--------------------------------

### Sceptre Launch Command Line Options

Source: https://docs.sceptre-project.org/latest/genindex

Lists the command-line options for 'sceptre-launch', including rollback control, pruning, confirmation, and specifying the path.

```bash
--disable-rollback
--enable-rollback
--prune
--yes
-p
-y
PATH
```

--------------------------------

### Sceptre Project Layout Example for DevOps

Source: https://docs.sceptre-project.org/latest/docs/architecture

Example of a Sceptre project layout for a DevOps team managing all infrastructure for their service. It includes network, frontend, application, and database configurations.

```yaml
-config
- prod
- network
- vpc.yaml
- subnet.yaml
- frontend
- api-gateway.yaml
- application
- lambda-get-item.yaml
- lambda-put-item.yaml
- database
- dynamodb.yaml
```

--------------------------------

### Sceptre Placeholder Examples

Source: https://docs.sceptre-project.org/latest/docs/resolvers

Provides specific examples of how placeholders appear for `!stack_output` in stack parameters and `sceptre_user_data` when using Jinja templates, and how resolvable properties like `sceptre_role` are handled.

```English
If you have a stack parameter referencing `!stack_output other_stack.yaml::OutputName`, and you run the `diff` command before other_stack.yaml has been deployed, the diff output will show the value of that parameter to be `"{ !StackOutput(other_stack.yaml::OutputName) }"`.
If you have a `sceptre_user_data` value used in a Jinja template referencing `!stack_output other_stack.yaml::OutputName` and you run the `dump template` command, the generated template will replace that value with `"StackOutputotherstackyamlOutputName"`. This isn’t as “pretty” as the sort of placeholder used for stack parameters, but the use of sceptre_user_data is broader, so it placeholder values can only be alphanumeric to reduce chances of it breaking the template.
Resolvable properties that are _always_ used when performing template operations (like `sceptre_role` and `template_bucket_name`) will resolve to `None` and not be used for those operations if they cannot be resolved.
```

--------------------------------

### Sceptre Template Configuration Example (S3)

Source: https://docs.sceptre-project.org/latest/docs/stack_config

An example demonstrating how to configure the 'template' key to load a CloudFormation template from an S3 bucket using a custom template handler.

```yaml
template:
  type: s3
  path: infra-templates/s3/v1/bucket.yaml
  parameters:
    <parameter1_name>: "value"
sceptre_user_data:

```

--------------------------------

### Sceptre CLI Create Module

Source: https://docs.sceptre-project.org/latest/_sources/apidoc/sceptre.cli

Documentation for the sceptre.cli.create submodule, which likely handles the creation of resources or projects via the Sceptre CLI.

```APIDOC
.. automodule:: sceptre.cli.create
    :members:
    :undoc-members:
    :show-inheritance:
```

--------------------------------

### Sceptre Command Path Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/terminology

Illustrates the structure of a Sceptre project directory and how command paths are defined for executing Sceptre commands against specific stacks or stack groups.

```text
.\n└── config\n    └── dev\n        ├── config.yaml\n        └── vpc.yaml
```

```text
.\n└── config\n    └── account-1\n        └── dev\n            └── eu-west-1\n                ├── config.yaml\n                └── vpc.yaml
```

--------------------------------

### List Stack Resources and Outputs

Source: https://docs.sceptre-project.org/latest/_sources/docs/get_started

Sceptre commands to retrieve information about running stacks, including listing resources and outputs for a specific stack or stack group.

```text
$ sceptre list resources dev
$ sceptre list resources dev/vpc.yaml
$ sceptre --ignore-dependencies list outputs dev/vpc.yaml
```

--------------------------------

### Sceptre Project Layout Example for Centralized Networking

Source: https://docs.sceptre-project.org/latest/docs/architecture

Example of a Sceptre project layout for centralized, company-wide networking. It demonstrates organizing VPC and subnet configurations for production and development environments.

```yaml
-config
- prod
- vpc.yaml
- public-subnet.yaml
- application-subnet.yaml
- database-subnet.yaml
- dev
- vpc.yaml
- public-subnet.yaml
- application-subnet.yaml
- database-subnet.yaml
```

--------------------------------

### Custom Hook Packaging (setup.py)

Source: https://docs.sceptre-project.org/latest/docs/hooks

This `setup.py` script demonstrates how to package a custom Sceptre hook as a Python package. It configures entry points to make the custom hook discoverable by Sceptre.

```python
from setuptools import setup

setup(
    name='custom_hook_package',
    py_modules=['<custom_hook_module_name>'],
    entry_points={
        'sceptre.hooks': [
            '<custom_hook_command_name> = <custom_hook_module_name>:CustomHook',
        ],
    }
)
```

--------------------------------

### Sceptre Command Line Help

Source: https://docs.sceptre-project.org/latest/_sources/docs/cli

Instructions on how to access help for the Sceptre CLI and its commands.

```text
sceptre
sceptre --help
sceptre COMMAND --help
```

--------------------------------

### Sceptre Project Layout Example for IAM Management

Source: https://docs.sceptre-project.org/latest/docs/architecture

Example of a Sceptre project layout for IAM management across multiple AWS accounts. It shows the organization of IAM role configurations for different accounts.

```yaml
-config
- account-1
- iam-role-admin.yaml
- iam-role-developer.yaml
- account-2
- iam-role-admin.yaml
- iam-role-developer.yaml
```

--------------------------------

### Sceptre HookProperty Descriptor

Source: https://docs.sceptre-project.org/latest/_modules/sceptre/hooks

A descriptor class for managing attributes that may contain Hook objects. It handles the setup of hooks, including cloning them for specific stacks and calling their setup methods. It supports nested lists and dictionaries.

```Python
[docs]
classHookProperty(object):
    """
    This is a descriptor class used to store an attribute that may contain
    Hook objects. Used to setup Hooks when added as a attribute. Supports
    nested dictionary and lists.

    :param name: Attribute suffix used to store the property in the instance.
    :type name: str
    """

    def__init__(self, name):
        self.name = "_" + name
        self.logger = logging.getLogger(__name__)

    def__get__(self, instance, type):
        """
        Attribute getter for Hook containing data structure.

        :return: The attribute stored with the suffix ``name`` in the instance.
        :rtype: dict or list
        """
        return getattr(instance, self.name)

    def__set__(self, instance: "Stack", value):
        """
        Attribute setter which adds a stack reference to any hooks in the
        data structure `value` and calls the setup method.

        """

        defsetup(attr, key, value: Hook):
            attr[key] = clone = value.clone_for_stack(instance)
            clone.setup()

        _call_func_on_values(setup, value, Hook)
        setattr(instance, self.name, value)
```

--------------------------------

### Sceptre Create Command Line Options

Source: https://docs.sceptre-project.org/latest/genindex

Details the command-line options specific to the 'sceptre-create' command, including rollback control, accepting defaults, and specifying change set names and paths.

```bash
--disable-rollback
--enable-rollback
--yes
-y
CHANGE_SET_NAME
PATH
```

--------------------------------

### Get Stack Status

Source: https://docs.sceptre-project.org/latest/_modules/sceptre/plan/actions

Retrieves the current status of a CloudFormation stack. If the stack does not exist, it returns 'PENDING'.

```python
def get_status(self):
        try:
            return self._get_status()
        except StackDoesNotExistError:
            return "PENDING"
```

--------------------------------

### Custom Resolver File Structure

Source: https://docs.sceptre-project.org/latest/_sources/docs/resolvers

Example file structure for a custom Sceptre resolver package.

```text
custom_resolver
├── custom_resolver.py
└── setup.py
```

--------------------------------

### Sceptre Plan Modules

Source: https://docs.sceptre-project.org/latest/_modules/index

Documentation for modules related to planning and executing stack changes, including actions, executors, and the plan itself.

```python
sceptre.plan
sceptre.plan.actions
sceptre.plan.executor
sceptre.plan.plan
```

--------------------------------

### Delete VPC Stack

Source: https://docs.sceptre-project.org/latest/_sources/docs/get_started

Command to delete the VPC stack and its associated AWS resources.

```text
$ sceptre delete dev/vpc.yaml
```

--------------------------------

### Sceptre CLI Launch Module

Source: https://docs.sceptre-project.org/latest/_sources/apidoc/sceptre.cli

Documentation for the sceptre.cli.launch submodule, potentially used for launching or deploying resources managed by Sceptre.

```APIDOC
.. automodule:: sceptre.cli.launch
    :members:
    :undoc-members:
    :show-inheritance:
```

--------------------------------

### Get Stack Timeout Configuration

Source: https://docs.sceptre-project.org/latest/_modules/sceptre/plan/actions

Returns the timeout configuration for a CloudFormation stack in minutes. Returns an empty dictionary if no timeout is set.

```python
def _get_stack_timeout(self):
        if self.stack.stack_timeout:
            return {"TimeoutInMinutes": self.stack.stack_timeout}
        else:
            return {}
```

--------------------------------

### Boto3 Client Retrieval

Source: https://docs.sceptre-project.org/latest/_modules/sceptre/connection_manager

Provides a thread-safe method to get a Boto3 client for a specified service. It caches clients to improve performance.

```python
def _get_client(self, service, region, profile, stack_name, sceptre_role):
        """
        Returns the Boto3 client associated with <service>.

        Equivalent to calling Boto3.client(<service>). Gets the client using
        ``boto_session``.

        :param service: The Boto3 service to return a client for.
        :type service: str
        :returns: The Boto3 client.
        :rtype: boto3.client.Client
        """
        with self._client_lock:
            key = (service, region, profile, stack_name, sceptre_role)
            if self._clients.get(key) is None:
                self.logger.debug("No %s client found, creating one...", service)
                self._clients[key] = self._get_session(
                    profile, region, sceptre_role
                ).client(service)

            return self._clients[key]
```

--------------------------------

### Update VPC Stack

Source: https://docs.sceptre-project.org/latest/_sources/docs/get_started

Command to update an existing VPC stack if its configuration or CloudFormation template has been modified.

```text
$ sceptre update dev/vpc.yaml
```

--------------------------------

### Get Domain from Region

Source: https://docs.sceptre-project.org/latest/_modules/sceptre/template

Determines the appropriate domain suffix based on the provided AWS region string. It specifically checks for Chinese regions.

```Python
def_domain_from_region(region):
        return "com.cn" if region.startswith("cn-") else "com"
```

--------------------------------

### Sceptre CLI and Configuration

Source: https://docs.sceptre-project.org/latest/_modules/sceptre/diffing/stack_differ

Documentation for the Sceptre command-line interface and configuration files, including StackGroup and Stack configurations.

```documentation
Command Line Interface
StackGroup Config
Stack Config
```

--------------------------------

### Sceptre Project Initialization

Source: https://docs.sceptre-project.org/latest/_modules/sceptre

This Python code snippet initializes the Sceptre project, setting up author information, versioning, and logging handlers. It configures deprecation warnings and ensures proper library logging behavior.

```Python
# -*- coding: utf-8 -*-

import logging
import warnings
import sys

from importlib.metadata import version

__author__ = "SceptreOrg"
__email__ = "sceptreorg@gmail.com"
__version__ = version(__package__ or __name__)


# Set up logging to ``/dev/null`` like a library is supposed to.
# http://docs.python.org/3.3/howto/logging.html#configuring-logging-for-a-library


[docs]
class NullHandler(logging.Handler):  # pragma: no cover


[docs]
    def emit(self, record):
        pass





if not sys.warnoptions:
    warnings.filterwarnings("default", category=DeprecationWarning, module="sceptre")

logging.getLogger("sceptre").addHandler(NullHandler())

```

--------------------------------

### Merged Dictionary Example

Source: https://docs.sceptre-project.org/latest/_sources/docs/stack_group_config

Illustrates the outcome of using `--merge-vars` when dealing with dictionary variables across multiple files.

```yaml
tags: {"Env": "prod", "Project": "Widget"}
```

--------------------------------

### Sceptre CLI Modules

Source: https://docs.sceptre-project.org/latest/_modules/index

This section lists the various modules available within the Sceptre command-line interface, including diffing, configuration, connection management, context, exceptions, helpers, hooks, planning, resolvers, and stack management.

```python
sceptre.cli.diff
sceptre.cli.helpers
sceptre.cli.launch
sceptre.cli.list
```
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