Submodel Server Base Adapter

The SubmodelAdapter is an abstract base class that defines the interface for all submodel server adapters in the Tractus-X SDK. It provides a standardized way to interact with different storage backends for submodel data.

Purpose

The base adapter establishes a common interface for:

• Reading submodel data from various storage backends
• Writing submodel data to storage systems
• Deleting submodel data when no longer needed
• Checking existence of submodel files or resources

By defining this abstract interface, the SDK enables pluggable storage backends without changing application code.

Interface Definition

Abstract Methods

All concrete adapter implementations must provide the following methods:

read(path: str)

Reads and returns the entire content of a submodel file.

Python

@abstractmethod
def read(self, path: str):
    """
    Return the entire content of a file
    """
    raise NotImplementedError

Parameters:

Parameter	Type	Description
path	str	Path to the file to read

Returns: File content (format depends on implementation)

write(path: str, content: bytes)

Writes content to a new or existing file.

Python

@abstractmethod
def write(self, path: str, content: bytes) -> None:
    """
    Write a new file
    """
    raise NotImplementedError

Parameters:

Parameter	Type	Description
path	str	Path where the file should be written
content	bytes	Content to write to the file

Returns: None

delete(path: str)

Deletes a specific file from storage.

Python

@abstractmethod
def delete(self, path: str) -> None:
    """
    Delete a specific file
    """
    raise NotImplementedError

Parameters:

Parameter	Type	Description
path	str	Path to the file to delete

Returns: None

exists(path: str)

Checks whether a file exists in storage.

Python

@abstractmethod
def exists(self, path: str) -> bool:
    """
    Check if a file exists
    """
    raise NotImplementedError

Parameters:

| Parameter | Type | Description | |-----------|-------|------------------------------------|| | path | str | Path to check for existence |

Returns: bool - True if file exists, False otherwise

Implementing Custom Adapters

To create a custom adapter for a specific storage backend:

Python

from tractusx_sdk.industry.adapters import SubmodelAdapter

class MyCustomAdapter(SubmodelAdapter):

    def __init__(self, connection_string: str):
        self.connection_string = connection_string
        # Initialize your storage connection

    def read(self, path: str):
        # Implement reading from your storage
        pass

    def write(self, path: str, content: bytes) -> None:
        # Implement writing to your storage
        pass

    def delete(self, path: str) -> None:
        # Implement deletion from your storage
        pass

    def exists(self, path: str) -> bool:
        # Implement existence check
        pass

Available Implementations

The SDK provides the following built-in adapter implementations:

• FileSystemAdapter - Local file system storage for submodels

Usage Pattern

Adapters are typically used through the factory pattern:

Python

from tractusx_sdk.industry.adapters import SubmodelAdapterFactory, SubmodelAdapterType

# Get a file system adapter
adapter = SubmodelAdapterFactory.get_file_system(root_path="./submodels")

# Use the adapter
if adapter.exists("part-info.json"):
    content = adapter.read("part-info.json")
else:
    adapter.write("part-info.json", content_bytes)

Best Practices

1. Always check existence before reading files to avoid errors
2. Handle exceptions appropriately in your implementations
3. Use relative paths for portability across adapters
4. Validate content before writing to ensure data integrity
5. Close resources properly in adapters that manage connections

Further Reading

• File System Adapter - Concrete implementation for local storage
• Submodel Adapter Factory - Factory for creating adapter instances
• Industry Library Overview

NOTICE

This work is licensed under the CC-BY-4.0.

• SPDX-License-Identifier: CC-BY-4.0
• SPDX-FileCopyrightText: 2025, 2026 Contributors to the Eclipse Foundation
• SPDX-FileCopyrightText: 2025, 2026 Catena-X Automotive Network e.V.
• SPDX-FileCopyrightText: 2025, 2026 LKS Next
• SPDX-FileCopyrightText: 2025, 2026 Mondragon Unibertsitatea
• Source URL: https://github.com/eclipse-tractusx/tractusx-sdk