feat: add SFTP integration for saving code to local disk

Added custom Open WebUI function for SSH/SFTP file operations:

**New Function: save_to_disk.py**
- save_file(): Write generated code to local filesystem via SFTP
- read_file(): Read files from local disk
- list_files(): List directory contents
- Configurable via Valves (host, port, username, paths)

**Custom Dockerfile (Dockerfile.webui)**
- Based on ghcr.io/open-webui/open-webui:main
- Installs paramiko library for SSH/SFTP support
- Creates .ssh directory for key storage

**Configuration Updates**
- Mount SSH private key from host (/root/.ssh/id_rsa)
- Mount functions directory for custom tools
- Build custom image with SFTP capabilities

**Usage in Open WebUI**
Claude can now use these tools to:
- Generate code and save it directly to your local disk
- Read existing files for context
- List project directories
- Create new files in any project

Default base path: /home/valknar/Projects
Authentication: SSH key-based (passwordless)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

ai/Dockerfile.webui

@@ -0,0 +1,7 @@
+FROM ghcr.io/open-webui/open-webui:main
+
+# Install paramiko for SFTP functionality
+RUN pip install --no-cache-dir paramiko
+
+# Create .ssh directory
+RUN mkdir -p /app/.ssh && chmod 700 /app/.ssh

ai/compose.yaml

@@ -24,7 +24,10 @@ services:
 
   # Open WebUI - ChatGPT-like interface for AI models
   webui:
-    image: ${AI_WEBUI_IMAGE:-ghcr.io/open-webui/open-webui:main}
+    build:
+      context: .
+      dockerfile: ./ai/Dockerfile.webui
+    image: ${AI_WEBUI_IMAGE:-ai_webui_custom:latest}
     container_name: ${AI_COMPOSE_PROJECT_NAME}_webui
     restart: unless-stopped
     environment:
@@ -63,6 +66,8 @@ services:
 
     volumes:
       - ai_webui_data:/app/backend/data
+      - ./ai/functions:/app/backend/data/functions:ro
+      - /root/.ssh/id_rsa:/app/.ssh/id_rsa:ro
     depends_on:
       - ai_postgres
       - litellm

ai/functions/save_to_disk.py

@@ -0,0 +1,195 @@
+"""
+title: Save Code to Local Disk via SFTP
+description: Saves generated code to local filesystem using SFTP
+author: Claude
+version: 1.0.0
+"""
+
+import paramiko
+import os
+from typing import Optional
+from pydantic import BaseModel, Field
+
+
+class Tools:
+    class Valves(BaseModel):
+        SFTP_HOST: str = Field(
+            default="vps",
+            description="SFTP host address"
+        )
+        SFTP_PORT: int = Field(
+            default=22,
+            description="SFTP port"
+        )
+        SFTP_USERNAME: str = Field(
+            default="valknar",
+            description="SFTP username"
+        )
+        SFTP_BASE_PATH: str = Field(
+            default="/home/valknar/Projects",
+            description="Base path for file operations"
+        )
+        SFTP_USE_KEY: bool = Field(
+            default=True,
+            description="Use SSH key authentication"
+        )
+        SFTP_KEY_PATH: str = Field(
+            default="/app/.ssh/id_rsa",
+            description="Path to SSH private key"
+        )
+
+    def __init__(self):
+        self.valves = self.Valves()
+
+    def save_file(
+        self,
+        filepath: str,
+        content: str,
+        __user__: dict = {},
+    ) -> str:
+        """
+        Save content to a file on the local disk via SFTP.
+
+        :param filepath: Relative path from base directory (e.g. "myproject/main.py")
+        :param content: File content to save
+        :return: Success message or error
+        """
+
+        try:
+            # Create SSH client
+            ssh = paramiko.SSHClient()
+            ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+
+            # Connect using SSH key or password
+            if self.valves.SFTP_USE_KEY:
+                ssh.connect(
+                    hostname=self.valves.SFTP_HOST,
+                    port=self.valves.SFTP_PORT,
+                    username=self.valves.SFTP_USERNAME,
+                    key_filename=self.valves.SFTP_KEY_PATH,
+                )
+            else:
+                # For password auth, would need SFTP_PASSWORD in valves
+                raise ValueError("Password auth not configured. Use SSH key authentication.")
+
+            # Open SFTP session
+            sftp = ssh.open_sftp()
+
+            # Construct full path
+            full_path = os.path.join(self.valves.SFTP_BASE_PATH, filepath)
+            directory = os.path.dirname(full_path)
+
+            # Create directories if they don't exist
+            try:
+                sftp.stat(directory)
+            except FileNotFoundError:
+                # Create parent directories recursively
+                dirs = []
+                temp_dir = directory
+                while temp_dir and temp_dir != '/':
+                    try:
+                        sftp.stat(temp_dir)
+                        break
+                    except FileNotFoundError:
+                        dirs.append(temp_dir)
+                        temp_dir = os.path.dirname(temp_dir)
+
+                for dir_path in reversed(dirs):
+                    sftp.mkdir(dir_path)
+
+            # Write file
+            with sftp.open(full_path, 'w') as f:
+                f.write(content)
+
+            sftp.close()
+            ssh.close()
+
+            return f"✅ File saved successfully to: {full_path}"
+
+        except Exception as e:
+            return f"❌ Error saving file: {str(e)}"
+
+    def read_file(
+        self,
+        filepath: str,
+        __user__: dict = {},
+    ) -> str:
+        """
+        Read content from a file on the local disk via SFTP.
+
+        :param filepath: Relative path from base directory (e.g. "myproject/main.py")
+        :return: File content or error message
+        """
+
+        try:
+            # Create SSH client
+            ssh = paramiko.SSHClient()
+            ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+
+            # Connect using SSH key
+            ssh.connect(
+                hostname=self.valves.SFTP_HOST,
+                port=self.valves.SFTP_PORT,
+                username=self.valves.SFTP_USERNAME,
+                key_filename=self.valves.SFTP_KEY_PATH,
+            )
+
+            # Open SFTP session
+            sftp = ssh.open_sftp()
+
+            # Construct full path
+            full_path = os.path.join(self.valves.SFTP_BASE_PATH, filepath)
+
+            # Read file
+            with sftp.open(full_path, 'r') as f:
+                content = f.read()
+
+            sftp.close()
+            ssh.close()
+
+            return content
+
+        except Exception as e:
+            return f"❌ Error reading file: {str(e)}"
+
+    def list_files(
+        self,
+        directory: str = ".",
+        __user__: dict = {},
+    ) -> str:
+        """
+        List files in a directory on the local disk via SFTP.
+
+        :param directory: Relative directory path from base (e.g. "myproject/")
+        :return: List of files or error message
+        """
+
+        try:
+            # Create SSH client
+            ssh = paramiko.SSHClient()
+            ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+
+            # Connect using SSH key
+            ssh.connect(
+                hostname=self.valves.SFTP_HOST,
+                port=self.valves.SFTP_PORT,
+                username=self.valves.SFTP_USERNAME,
+                key_filename=self.valves.SFTP_KEY_PATH,
+            )
+
+            # Open SFTP session
+            sftp = ssh.open_sftp()
+
+            # Construct full path
+            full_path = os.path.join(self.valves.SFTP_BASE_PATH, directory)
+
+            # List files
+            files = sftp.listdir(full_path)
+
+            sftp.close()
+            ssh.close()
+
+            return f"📁 Files in {full_path}:\n" + "\n".join(f"  - {f}" for f in files)
+
+        except Exception as e:
+            return f"❌ Error listing files: {str(e)}"