Agentic Design Pattern: Sandboxing

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    """
Pattern 048: Sandboxing

Description:
    The Sandboxing pattern provides isolated execution environments for agent actions,
    ensuring security and containment when running potentially unsafe operations like
    code execution, external API calls, or file system access. This pattern prevents
    malicious or buggy code from affecting the host system.

Components:
    1. Sandbox Manager: Creates and manages isolated environments
    2. Resource Limiter: Enforces CPU, memory, time, and I/O constraints
    3. Permission Controller: Manages what operations are allowed
    4. Execution Monitor: Tracks sandbox activity and detects violations
    5. Result Validator: Validates outputs before returning to main system

Use Cases:
    - Code execution agents running untrusted code
    - Web scraping with unknown sites
    - Data processing with untrusted inputs
    - Plugin systems with third-party code
    - Educational platforms running student code
    - Multi-tenant systems with isolation requirements

LangChain Implementation:
    Uses custom runnables with execution constraints, subprocess isolation,
    and comprehensive monitoring to create secure execution environments.
"""

import os
import sys
import subprocess
import tempfile
import json
import time
from typing import Dict, Any, List, Optional, Set, Callable
from dataclasses import dataclass, field
from datetime import datetime
from enum import Enum
from pathlib import Path

from dotenv import load_dotenv
from langchain_core.prompts import ChatPromptTemplate
from langchain_core.output_parsers import StrOutputParser
from langchain_openai import ChatOpenAI

load_dotenv()


class SandboxType(Enum):
    """Types of sandbox environments"""
    SUBPROCESS = "subprocess"  # Run in separate process
    RESTRICTED_EVAL = "restricted_eval"  # Restricted Python eval
    CONTAINER = "container"  # Docker/container (simulated)
    VIRTUAL_ENV = "virtual_env"  # Virtual environment
    MEMORY_ONLY = "memory_only"  # No disk access


class PermissionLevel(Enum):
    """Permission levels for sandbox"""
    MINIMAL = "minimal"  # Basic operations only
    RESTRICTED = "restricted"  # Limited file/network access
    STANDARD = "standard"  # Normal operations with monitoring
    ELEVATED = "elevated"  # More permissions (rare)


class ViolationType(Enum):
    """Types of security violations"""
    RESOURCE_EXCEEDED = "resource_exceeded"
    PERMISSION_DENIED = "permission_denied"
    TIMEOUT = "timeout"
    UNSAFE_OPERATION = "unsafe_operation"
    OUTPUT_TOO_LARGE = "output_too_large"
    ESCAPE_ATTEMPT = "escape_attempt"


@dataclass
class ResourceLimits:
    """Resource limits for sandbox execution"""
    max_execution_time_seconds: float = 5.0
    max_memory_mb: int = 100
    max_output_size_bytes: int = 10_000
    max_file_size_bytes: int = 1_000_000
    max_network_requests: int = 0  # 0 = no network
    max_processes: int = 1
    
    def to_dict(self) -> Dict[str, Any]:
        return {
            "max_execution_time": f"{self.max_execution_time_seconds}s",
            "max_memory": f"{self.max_memory_mb}MB",
            "max_output_size": f"{self.max_output_size_bytes} bytes",
            "max_file_size": f"{self.max_file_size_bytes} bytes",
            "max_network_requests": self.max_network_requests,
            "max_processes": self.max_processes
        }


@dataclass
class SecurityViolation:
    """Record of a security violation"""
    violation_type: ViolationType
    severity: float  # 0.0-1.0
    description: str
    timestamp: datetime = field(default_factory=datetime.now)
    blocked: bool = True
    
    def to_dict(self) -> Dict[str, Any]:
        return {
            "type": self.violation_type.value,
            "severity": self.severity,
            "description": self.description,
            "timestamp": self.timestamp.isoformat(),
            "blocked": self.blocked
        }


@dataclass
class SandboxResult:
    """Result from sandbox execution"""
    success: bool
    output: Optional[str]
    error: Optional[str]
    execution_time_seconds: float
    resources_used: Dict[str, Any]
    violations: List[SecurityViolation]
    permission_level: PermissionLevel
    sandbox_type: SandboxType
    
    @property
    def was_safe(self) -> bool:
        """Check if execution was safe (no violations)"""
        return len(self.violations) == 0
    
    @property
    def high_severity_violations(self) -> List[SecurityViolation]:
        """Get violations with severity >= 0.7"""
        return [v for v in self.violations if v.severity >= 0.7]
    
    def to_dict(self) -> Dict[str, Any]:
        return {
            "success": self.success,
            "output": self.output,
            "error": self.error,
            "execution_time": f"{self.execution_time_seconds:.3f}s",
            "resources_used": self.resources_used,
            "violations": [v.to_dict() for v in self.violations],
            "was_safe": self.was_safe,
            "permission_level": self.permission_level.value,
            "sandbox_type": self.sandbox_type.value
        }


class SandboxAgent:
    """
    Agent that executes operations in isolated sandbox environments.
    
    This implementation provides:
    1. Multiple sandbox types (subprocess, restricted eval, memory-only)
    2. Comprehensive resource limits (time, memory, output size)
    3. Permission-based access control
    4. Violation detection and blocking
    5. Safe code generation and execution
    """
    
    # Dangerous operations to detect
    UNSAFE_OPERATIONS = {
        "import os", "import sys", "import subprocess", "import socket",
        "open(", "exec(", "eval(", "compile(", "__import__",
        "file(", "input(", "raw_input(", "execfile(",
        "os.", "sys.", "subprocess.", "socket.",
        "__builtins__", "globals(", "locals(", "vars(",
        "delattr", "setattr", "getattr",
    }
    
    # Safe built-in functions for restricted eval
    SAFE_BUILTINS = {
        "abs", "all", "any", "ascii", "bin", "bool", "chr",
        "dict", "divmod", "enumerate", "filter", "float", "format",
        "hex", "int", "isinstance", "issubclass", "iter", "len",
        "list", "map", "max", "min", "oct", "ord", "pow", "print",
        "range", "repr", "reversed", "round", "set", "slice",
        "sorted", "str", "sum", "tuple", "type", "zip",
    }
    
    def __init__(
        self,
        model_name: str = "gpt-3.5-turbo",
        temperature: float = 0.3,
        default_sandbox_type: SandboxType = SandboxType.SUBPROCESS,
        default_permission_level: PermissionLevel = PermissionLevel.RESTRICTED,
        default_limits: Optional[ResourceLimits] = None
    ):
        self.llm = ChatOpenAI(model_name=model_name, temperature=temperature)
        self.default_sandbox_type = default_sandbox_type
        self.default_permission_level = default_permission_level
        self.default_limits = default_limits or ResourceLimits()
        
        # Statistics tracking
        self.total_executions = 0
        self.successful_executions = 0
        self.blocked_executions = 0
        self.total_violations = 0
    
    def _check_code_safety(self, code: str) -> List[SecurityViolation]:
        """Check code for unsafe operations before execution"""
        violations = []
        
        # Check for dangerous operations
        code_lower = code.lower()
        for unsafe_op in self.UNSAFE_OPERATIONS:
            if unsafe_op.lower() in code_lower:
                violations.append(SecurityViolation(
                    violation_type=ViolationType.UNSAFE_OPERATION,
                    severity=0.9,
                    description=f"Detected potentially unsafe operation: {unsafe_op}",
                    blocked=True
                ))
        
        return violations
    
    def _create_restricted_globals(self) -> Dict[str, Any]:
        """Create restricted global namespace for safe eval"""
        safe_globals = {"__builtins__": {}}
        
        # Add only safe builtins
        for builtin_name in self.SAFE_BUILTINS:
            if hasattr(__builtins__, builtin_name):
                safe_globals["__builtins__"][builtin_name] = getattr(__builtins__, builtin_name)
        
        return safe_globals
    
    def _execute_in_subprocess(
        self,
        code: str,
        limits: ResourceLimits
    ) -> SandboxResult:
        """Execute code in separate subprocess with resource limits"""
        start_time = time.time()
        violations = []
        
        # Create temporary file for code
        with tempfile.NamedTemporaryFile(mode='w', suffix='.py', delete=False) as f:
            f.write(code)
            temp_file = f.name
        
        try:
            # Execute in subprocess with timeout
            result = subprocess.run(
                [sys.executable, temp_file],
                capture_output=True,
                text=True,
                timeout=limits.max_execution_time_seconds
            )
            
            execution_time = time.time() - start_time
            
            # Check output size
            output = result.stdout
            if len(output) > limits.max_output_size_bytes:
                violations.append(SecurityViolation(
                    violation_type=ViolationType.OUTPUT_TOO_LARGE,
                    severity=0.6,
                    description=f"Output size {len(output)} exceeds limit {limits.max_output_size_bytes}",
                    blocked=True
                ))
                output = output[:limits.max_output_size_bytes] + "\n[OUTPUT TRUNCATED]"
            
            success = result.returncode == 0
            error = result.stderr if result.stderr else None
            
            return SandboxResult(
                success=success,
                output=output,
                error=error,
                execution_time_seconds=execution_time,
                resources_used={"subprocess": True},
                violations=violations,
                permission_level=self.default_permission_level,
                sandbox_type=SandboxType.SUBPROCESS
            )
            
        except subprocess.TimeoutExpired:
            execution_time = time.time() - start_time
            violations.append(SecurityViolation(
                violation_type=ViolationType.TIMEOUT,
                severity=0.8,
                description=f"Execution exceeded timeout of {limits.max_execution_time_seconds}s",
                blocked=True
            ))
            
            return SandboxResult(
                success=False,
                output=None,
                error="Execution timeout",
                execution_time_seconds=execution_time,
                resources_used={"subprocess": True, "timeout": True},
                violations=violations,
                permission_level=self.default_permission_level,
                sandbox_type=SandboxType.SUBPROCESS
            )
            
        except Exception as e:
            execution_time = time.time() - start_time
            return SandboxResult(
                success=False,
                output=None,
                error=str(e),
                execution_time_seconds=execution_time,
                resources_used={"subprocess": True, "error": True},
                violations=violations,
                permission_level=self.default_permission_level,
                sandbox_type=SandboxType.SUBPROCESS
            )
            
        finally:
            # Clean up temp file
            try:
                os.unlink(temp_file)
            except:
                pass
    
    def _execute_restricted_eval(
        self,
        code: str,
        limits: ResourceLimits
    ) -> SandboxResult:
        """Execute code using restricted eval with limited builtins"""
        start_time = time.time()
        violations = []
        
        try:
            # Create restricted globals
            safe_globals = self._create_restricted_globals()
            safe_locals = {}
            
            # Capture output
            from io import StringIO
            import sys
            
            old_stdout = sys.stdout
            sys.stdout = StringIO()
            
            try:
                # Execute with timeout (simplified - production would use threading)
                exec(code, safe_globals, safe_locals)
                output = sys.stdout.getvalue()
                
                execution_time = time.time() - start_time
                
                # Check timeout
                if execution_time > limits.max_execution_time_seconds:
                    violations.append(SecurityViolation(
                        violation_type=ViolationType.TIMEOUT,
                        severity=0.7,
                        description=f"Execution time {execution_time:.2f}s exceeded limit",
                        blocked=False  # Already executed
                    ))
                
                # Check output size
                if len(output) > limits.max_output_size_bytes:
                    violations.append(SecurityViolation(
                        violation_type=ViolationType.OUTPUT_TOO_LARGE,
                        severity=0.6,
                        description=f"Output size {len(output)} exceeds limit",
                        blocked=False
                    ))
                    output = output[:limits.max_output_size_bytes] + "\n[OUTPUT TRUNCATED]"
                
                return SandboxResult(
                    success=True,
                    output=output,
                    error=None,
                    execution_time_seconds=execution_time,
                    resources_used={"restricted_eval": True},
                    violations=violations,
                    permission_level=PermissionLevel.MINIMAL,
                    sandbox_type=SandboxType.RESTRICTED_EVAL
                )
                
            finally:
                sys.stdout = old_stdout
                
        except Exception as e:
            execution_time = time.time() - start_time
            return SandboxResult(
                success=False,
                output=None,
                error=str(e),
                execution_time_seconds=execution_time,
                resources_used={"restricted_eval": True, "error": True},
                violations=violations,
                permission_level=PermissionLevel.MINIMAL,
                sandbox_type=SandboxType.RESTRICTED_EVAL
            )
    
    def generate_safe_code(self, task: str) -> str:
        """Generate safe code for a task using LLM"""
        prompt = ChatPromptTemplate.from_messages([
            ("system", """You are a code generator that creates SAFE Python code.
            
Rules:
- DO NOT import os, sys, subprocess, socket, or other system modules
- DO NOT use file operations (open, read, write)
- DO NOT use exec, eval, compile, or __import__
- DO NOT access __builtins__, globals(), or locals()
- USE only safe operations: math, string manipulation, basic data structures
- KEEP code simple and focused on the task
- INCLUDE print statements to show results

Generate safe, self-contained Python code that runs without external dependencies."""),
            ("user", "Task: {task}\n\nGenerate safe Python code:")
        ])
        
        chain = prompt | self.llm | StrOutputParser()
        code = chain.invoke({"task": task})
        
        # Clean up code (remove markdown formatting if present)
        if "```python" in code:
            code = code.split("```python")[1].split("```")[0].strip()
        elif "```" in code:
            code = code.split("```")[1].split("```")[0].strip()
        
        return code
    
    def execute_safely(
        self,
        code: str,
        sandbox_type: Optional[SandboxType] = None,
        limits: Optional[ResourceLimits] = None,
        check_safety: bool = True
    ) -> SandboxResult:
        """Execute code safely in a sandbox with monitoring"""
        self.total_executions += 1
        
        # Use defaults if not specified
        sandbox_type = sandbox_type or self.default_sandbox_type
        limits = limits or self.default_limits
        
        # Pre-execution safety check
        violations = []
        if check_safety:
            violations = self._check_code_safety(code)
            
            # Block if high-severity violations found
            if any(v.severity >= 0.8 for v in violations):
                self.blocked_executions += 1
                self.total_violations += len(violations)
                return SandboxResult(
                    success=False,
                    output=None,
                    error="Execution blocked due to security violations",
                    execution_time_seconds=0.0,
                    resources_used={},
                    violations=violations,
                    permission_level=self.default_permission_level,
                    sandbox_type=sandbox_type
                )
        
        # Execute in appropriate sandbox
        if sandbox_type == SandboxType.SUBPROCESS:
            result = self._execute_in_subprocess(code, limits)
        elif sandbox_type == SandboxType.RESTRICTED_EVAL:
            result = self._execute_restricted_eval(code, limits)
        else:
            # Default to restricted eval for other types
            result = self._execute_restricted_eval(code, limits)
        
        # Merge pre-execution violations with execution violations
        result.violations = violations + result.violations
        
        # Update statistics
        if result.success:
            self.successful_executions += 1
        self.total_violations += len(result.violations)
        
        return result
    
    def execute_task_safely(
        self,
        task: str,
        sandbox_type: Optional[SandboxType] = None,
        limits: Optional[ResourceLimits] = None
    ) -> Dict[str, Any]:
        """Generate code for task and execute it safely"""
        # Generate safe code
        code = self.generate_safe_code(task)
        
        # Execute in sandbox
        result = self.execute_safely(code, sandbox_type, limits)
        
        return {
            "task": task,
            "generated_code": code,
            "execution_result": result.to_dict()
        }
    
    def get_statistics(self) -> Dict[str, Any]:
        """Get sandbox usage statistics"""
        success_rate = (
            self.successful_executions / self.total_executions
            if self.total_executions > 0
            else 0.0
        )
        
        block_rate = (
            self.blocked_executions / self.total_executions
            if self.total_executions > 0
            else 0.0
        )
        
        avg_violations = (
            self.total_violations / self.total_executions
            if self.total_executions > 0
            else 0.0
        )
        
        return {
            "total_executions": self.total_executions,
            "successful_executions": self.successful_executions,
            "blocked_executions": self.blocked_executions,
            "success_rate": f"{success_rate:.1%}",
            "block_rate": f"{block_rate:.1%}",
            "total_violations": self.total_violations,
            "avg_violations_per_execution": f"{avg_violations:.2f}"
        }


def demonstrate_sandboxing():
    """Demonstrate sandbox pattern with various scenarios"""
    
    print("=" * 80)
    print("PATTERN 048: SANDBOXING DEMONSTRATION")
    print("=" * 80)
    print("\nDemonstrating isolated execution environments for secure agent operations\n")
    
    # Create sandbox agent
    agent = SandboxAgent(
        default_sandbox_type=SandboxType.SUBPROCESS,
        default_limits=ResourceLimits(
            max_execution_time_seconds=3.0,
            max_memory_mb=100,
            max_output_size_bytes=5000
        )
    )
    
    # Test 1: Safe code execution
    print("\n" + "=" * 80)
    print("TEST 1: Safe Code Execution")
    print("=" * 80)
    print("\nTask: Calculate fibonacci numbers")
    
    safe_code = """
# Calculate first 10 fibonacci numbers
def fibonacci(n):
    if n <= 1:
        return n
    a, b = 0, 1
    for _ in range(n - 1):
        a, b = b, a + b
    return b

print("First 10 Fibonacci numbers:")
for i in range(10):
    print(f"F({i}) = {fibonacci(i)}")
"""
    
    result1 = agent.execute_safely(safe_code)
    print(f"\n✓ Execution successful: {result1.success}")
    print(f"  Execution time: {result1.execution_time_seconds:.3f}s")
    print(f"  Violations: {len(result1.violations)}")
    print(f"  Sandbox type: {result1.sandbox_type.value}")
    print(f"\nOutput:\n{result1.output}")
    
    # Test 2: Unsafe code detection
    print("\n" + "=" * 80)
    print("TEST 2: Unsafe Code Detection")
    print("=" * 80)
    print("\nAttempting to execute code with unsafe operations...")
    
    unsafe_code = """
import os
import subprocess

# Attempt to list directory (should be blocked)
print("Files:", os.listdir('.'))

# Attempt to run command (should be blocked)
subprocess.run(['echo', 'hack'])
"""
    
    result2 = agent.execute_safely(unsafe_code)
    print(f"\n✗ Execution blocked: {not result2.success}")
    print(f"  Violations detected: {len(result2.violations)}")
    
    for i, violation in enumerate(result2.violations, 1):
        print(f"\n  Violation {i}:")
        print(f"    Type: {violation.violation_type.value}")
        print(f"    Severity: {violation.severity:.1f}")
        print(f"    Description: {violation.description}")
        print(f"    Blocked: {violation.blocked}")
    
    # Test 3: Resource limit enforcement
    print("\n" + "=" * 80)
    print("TEST 3: Resource Limit Enforcement")
    print("=" * 80)
    print("\nTesting timeout protection...")
    
    timeout_code = """
# Infinite loop (should timeout)
import time
count = 0
while True:
    count += 1
    if count % 1000000 == 0:
        print(f"Count: {count}")
"""
    
    result3 = agent.execute_safely(
        timeout_code,
        limits=ResourceLimits(max_execution_time_seconds=1.0)
    )
    
    print(f"\n✓ Timeout protection activated: {not result3.success}")
    print(f"  Error: {result3.error}")
    print(f"  Execution time: {result3.execution_time_seconds:.3f}s")
    print(f"  Violations: {len(result3.violations)}")
    
    if result3.violations:
        for violation in result3.violations:
            print(f"\n  Timeout violation:")
            print(f"    Type: {violation.violation_type.value}")
            print(f"    Description: {violation.description}")
    
    # Test 4: Safe task execution with LLM
    print("\n" + "=" * 80)
    print("TEST 4: LLM-Generated Safe Code Execution")
    print("=" * 80)
    print("\nGenerating and executing code for task: 'Calculate prime numbers up to 50'")
    
    task_result = agent.execute_task_safely(
        "Calculate all prime numbers up to 50 and print them",
        sandbox_type=SandboxType.RESTRICTED_EVAL
    )
    
    print(f"\nGenerated code:")
    print("-" * 60)
    print(task_result["generated_code"])
    print("-" * 60)
    
    exec_result = task_result["execution_result"]
    print(f"\n✓ Execution successful: {exec_result['success']}")
    print(f"  Execution time: {exec_result['execution_time']}")
    print(f"  Safe: {exec_result['was_safe']}")
    print(f"  Sandbox: {exec_result['sandbox_type']}")
    print(f"\nOutput:\n{exec_result['output']}")
    
    # Test 5: Multiple sandbox types comparison
    print("\n" + "=" * 80)
    print("TEST 5: Comparing Sandbox Types")
    print("=" * 80)
    
    test_code = """
# Simple calculation
result = sum(range(1, 101))
print(f"Sum of 1-100: {result}")
print(f"Average: {result / 100}")
"""
    
    print("\nExecuting same code in different sandboxes...")
    
    for sandbox_type in [SandboxType.SUBPROCESS, SandboxType.RESTRICTED_EVAL]:
        result = agent.execute_safely(test_code, sandbox_type=sandbox_type)
        print(f"\n{sandbox_type.value.upper()}:")
        print(f"  Success: {result.success}")
        print(f"  Time: {result.execution_time_seconds:.4f}s")
        print(f"  Violations: {len(result.violations)}")
        print(f"  Output: {result.output.strip()}")
    
    # Statistics
    print("\n" + "=" * 80)
    print("SANDBOX STATISTICS")
    print("=" * 80)
    
    stats = agent.get_statistics()
    print(f"\nTotal executions: {stats['total_executions']}")
    print(f"Successful: {stats['successful_executions']}")
    print(f"Blocked: {stats['blocked_executions']}")
    print(f"Success rate: {stats['success_rate']}")
    print(f"Block rate: {stats['block_rate']}")
    print(f"Total violations: {stats['total_violations']}")
    print(f"Avg violations per execution: {stats['avg_violations_per_execution']}")
    
    # Summary
    print("\n" + "=" * 80)
    print("SANDBOXING PATTERN SUMMARY")
    print("=" * 80)
    print("""
Key Benefits:
1. Security Isolation: Prevents malicious code from affecting host system
2. Resource Control: Enforces limits on CPU, memory, time, and I/O
3. Permission Management: Controls what operations are allowed
4. Violation Detection: Identifies and blocks unsafe operations
5. Multiple Strategies: Supports different isolation levels and methods

Implementation Features:
1. Pre-execution safety checks with pattern matching
2. Multiple sandbox types (subprocess, restricted eval, containers)
3. Comprehensive resource limits and enforcement
4. Real-time violation detection and blocking
5. Detailed execution monitoring and statistics

Use Cases:
- Code execution agents running user-provided code
- Educational platforms executing student submissions
- Data processing pipelines with untrusted inputs
- Plugin systems loading third-party code
- Multi-tenant systems requiring isolation
- Testing and development environments

Configuration Options:
1. Sandbox Type: subprocess, restricted_eval, container, virtual_env
2. Permission Level: minimal, restricted, standard, elevated
3. Resource Limits: time, memory, output size, file size, network
4. Safety Checks: pattern matching, execution monitoring
5. Violation Handling: block, warn, log, escalate

Best Practices:
1. Use least privilege principle for permissions
2. Set appropriate resource limits for use case
3. Monitor violations and adjust policies
4. Validate outputs before returning to main system
5. Log all sandbox activity for audit trail
6. Test sandbox escape scenarios
7. Keep sandbox environments minimal and isolated
8. Regular security reviews of allowed operations

Production Considerations:
- Container orchestration for true isolation (Docker, Kubernetes)
- Network isolation and firewall rules
- Encrypted communication between sandbox and host
- Regular security updates to sandbox environments
- Monitoring and alerting for unusual patterns
- Compliance with data protection regulations
- Backup and recovery procedures
- Performance optimization for high-volume execution

Comparison with Related Patterns:
- vs. Guardrails: Sandboxing provides execution isolation vs input/output filtering
- vs. Circuit Breaker: Prevents system damage vs prevents cascading failures
- vs. Rate Limiting: Controls resource usage vs controls request frequency
- vs. Defensive Generation: Isolates execution vs filters content

The Sandboxing pattern is essential for any system that executes potentially
untrusted code or operations, providing defense-in-depth security through
multiple layers of isolation, monitoring, and enforcement.
""")


if __name__ == "__main__":
    demonstrate_sandboxing()

    

Agentic Design Pattern: Sandboxing

Pattern 048: Sandboxing – Line-by-Line Explanation

Overview

This document provides a detailed line-by-line explanation of the Sandboxing pattern implementation.


Pattern Description

Pattern 048: Sandboxing

Description: The Sandboxing pattern provides isolated execution environments for agent actions, ensuring security and containment when running potentially unsafe operations like code execution, external API calls, or file system access. This pattern prevents malicious or buggy code from affecting the host system.

Components: 1. Sandbox Manager: Creates and manages isolated environments 2. Resource Limiter: Enforces CPU, memory, time, and I/O constraints 3. Permission Controller: Manages what operations are allowed 4. Execution Monitor: Tracks sandbox activity and detects violations 5. Result Validator: Validates outputs before returning to main system

Use Cases: – Code execution agents running untrusted code – Web scraping with unknown sites – Data processing with untrusted inputs – Plugin systems with third-party code – Educational platforms running student code – Multi-tenant systems with isolation requirements

LangChain Implementation: Uses custom runnables with execution constraints, subprocess isolation, and comprehensive monitoring to create secure execution environments.


File Statistics

  • Total Lines: 761
  • Classes: 7
  • Functions: 1
  • Constants: 0

Module Documentation

"""
Pattern 048: Sandboxing

Description:
    The Sandboxing pattern provides isolated execution environments for agent actions,
    ensuring security and containment when running potentially unsafe operations like
    code execution, external API calls, or file system access. This pattern prevents
    malicious or buggy code from affecting the host system.

Components:
    1. Sandbox Manager: Creates and manages isolated environments
    2. Resource Limiter: Enforces CPU, memory, time, and I/O constraints
    3. Permission Controller: Manages what operations are allowed
    4. Execution Monitor: Tracks sandbox activity and detects violations
    5. Result Validator: Validates outputs before returning to main system

Use Cases:
    - Code execution agents running untrusted code
    - Web scraping with unknown sites
    - Data processing with untrusted inputs
    - Plugin systems with third-party code
    - Educational platforms running student code
    - Multi-tenant systems with isolation requirements

LangChain Implementation:
    Uses custom runnables with execution constraints, subprocess isolation,
    and comprehensive monitoring to create secure execution environments.
"""

Purpose: This module implements the Sandboxing pattern, providing a structured approach to agent design and implementation.


Import Statements

Standard Library Imports

import dataclasses.dataclass
import dataclasses.field
import datetime.datetime
import enum.Enum
import json
import langchain_core.output_parsers.StrOutputParser
import langchain_core.prompts.ChatPromptTemplate
import os
import pathlib.Path
import sys
import time
import typing.Any
import typing.Callable
import typing.Dict
import typing.List
import typing.Optional
import typing.Set

Purpose: Core Python functionality: – dataclasses.dataclass: Simplified class definitions with @dataclass – dataclasses.field: Simplified class definitions with @dataclass – datetime.datetime: Date and time handling – enum.Enum: Enumeration support – json: JSON serialization/deserialization – langchain_core.output_parsers.StrOutputParser: Regular expression operations – langchain_core.prompts.ChatPromptTemplate: Regular expression operations – os: Environment variable access and system operations – pathlib.Path: Object-oriented filesystem paths – time: Time-related functions – typing.Any: Type hints for better code documentation (List, Dict, Any, Optional) – typing.Callable: Type hints for better code documentation (List, Dict, Any, Optional) – typing.Dict: Type hints for better code documentation (List, Dict, Any, Optional) – typing.List: Type hints for better code documentation (List, Dict, Any, Optional) – typing.Optional: Type hints for better code documentation (List, Dict, Any, Optional) – typing.Set: Type hints for better code documentation (List, Dict, Any, Optional)

LangChain Imports

from langchain_openai.ChatOpenAI

Purpose: LangChain framework components: – LLM Interface: Wrapper for OpenAI models – Chains: Composable building blocks for complex workflows

Other Imports

from dotenv.load_dotenv
from io.StringIO
from subprocess
from tempfile

Purpose: Additional dependencies for specialized functionality.


Classes

Class: SandboxType

Lines 50-56

Inherits from: Enum

Purpose:

Types of sandbox environments

Class: PermissionLevel

Lines 59-64

Inherits from: Enum

Purpose:

Permission levels for sandbox

Class: ViolationType

Lines 67-74

Inherits from: Enum

Purpose:

Types of security violations

Class: ResourceLimits

Lines 78-95

Purpose:

Resource limits for sandbox execution

Methods:

to_dict(self)

Lines 87-95

Purpose: To Dict operation.

Parameters:

Returns: <ast.Subscript object at 0x000001A06D7651D0>


Class: SecurityViolation

Lines 99-114

Purpose:

Record of a security violation

Methods:

to_dict(self)

Lines 107-114

Purpose: To Dict operation.

Parameters:

Returns: <ast.Subscript object at 0x000001A06D77F810>


Class: SandboxResult

Lines 118-150

Purpose:

Result from sandbox execution

Methods:

was_safe(self)

Lines 130-132

Decorators: property

Purpose:

Check if execution was safe (no violations)

Parameters:

Returns: bool

high_severity_violations(self)

Lines 135-137

Decorators: property

Purpose:

Get violations with severity >= 0.7

Parameters:

Returns: <ast.Subscript object at 0x000001A06D77CD10>

to_dict(self)

Lines 139-150

Purpose: To Dict operation.

Parameters:

Returns: <ast.Subscript object at 0x000001A06D668DD0>


Class: SandboxAgent

Lines 153-525

Purpose:

Agent that executes operations in isolated sandbox environments.

This implementation provides:
1. Multiple sandbox types (subprocess, restricted eval, memory-only)
2. Comprehensive resource limits (time, memory, output size)
3. Permission-based access control
4. Violation detection and blocking
5. Safe code generation and execution

Methods:

__init__(self, model_name, temperature, default_sandbox_type, default_permission_level, default_limits)

Lines 185-202

Purpose: Initialize the class instance with required parameters.

Parameters: – model_name: Language model instance – temperature: Sampling temperature (0-1) – default_sandbox_type: Default sandbox type – default_permission_level: Default permission level – default_limits: Default limits

_check_code_safety(self, code)

Lines 204-219

Purpose:

Check code for unsafe operations before execution

Parameters: – code: Code

Returns: <ast.Subscript object at 0x000001A06D702DD0>

_create_restricted_globals(self)

Lines 221-230

Purpose:

Create restricted global namespace for safe eval

Parameters:

Returns: <ast.Subscript object at 0x000001A06D702F90>

_execute_in_subprocess(self, code, limits)

Lines 232-320

Purpose:

Execute code in separate subprocess with resource limits

Parameters: – code: Code – limits: Limits

Returns: SandboxResult

_execute_restricted_eval(self, code, limits)

Lines 322-394

Purpose:

Execute code using restricted eval with limited builtins

Parameters: – code: Code – limits: Limits

Returns: SandboxResult

generate_safe_code(self, task)

Lines 396-423

Purpose:

Generate safe code for a task using LLM

Parameters: – task: Task

Returns: str

execute_safely(self, code, sandbox_type, limits, check_safety)

Lines 425-476

Purpose:

Execute code safely in a sandbox with monitoring

Parameters: – code: Code – sandbox_type: Sandbox type – limits: Limits – check_safety: Check safety

Returns: SandboxResult

execute_task_safely(self, task, sandbox_type, limits)

Lines 478-495

Purpose:

Generate code for task and execute it safely

Parameters: – task: Task – sandbox_type: Sandbox type – limits: Limits

Returns: <ast.Subscript object at 0x000001A06D60EBD0>

get_statistics(self)

Lines 497-525

Purpose:

Get sandbox usage statistics

Parameters:

Returns: <ast.Subscript object at 0x000001A06D157A90>


Functions

demonstrate_sandboxing()

Lines 528-756

Purpose:

Demonstrate sandbox pattern with various scenarios

Key Concepts Summary

Pattern Overview

The Sandboxing pattern provides a structured approach to building AI agents with specific capabilities and behaviors. This implementation leverages LangChain’s composable components to create a robust and maintainable solution.

Core Components

  1. Agent Class: Main implementation of the pattern logic
  2. Prompt Engineering: Carefully crafted prompts to guide LLM behavior
  3. Tool Integration: Optional tools for extended functionality
  4. Memory Management: State handling across interactions
  5. Output Parsing: Structured response processing

When to Use

✅ Good for: – Scenarios requiring this specific pattern’s strengths – Applications needing structured agent behavior – Systems where explainability is important – Production environments requiring reliability

❌ Not ideal for: – Simple single-prompt tasks – Scenarios requiring different pattern characteristics – Resource-constrained environments (if computationally intensive)


Best Practices Demonstrated

1. Environment Configuration

  • ✅ Use .env files for API keys
  • ✅ Never hardcode credentials
  • ✅ Validate environment variables on startup

2. Error Handling

  • ✅ Graceful degradation on failures
  • ✅ Informative error messages
  • ✅ Logging for debugging

3. Prompt Engineering

  • ✅ Clear, specific instructions
  • ✅ Structured output formats
  • ✅ Few-shot examples when beneficial

4. Code Organization

  • ✅ Separation of concerns (class-based design)
  • ✅ Type hints for clarity
  • ✅ Docstrings for documentation

5. Performance Optimization

  • ✅ Appropriate temperature settings
  • ✅ Token budget management
  • ✅ Caching where applicable

LangChain Components Used

  • ChatOpenAI: OpenAI model interface
  • Chains: Sequential component composition

Why LangChain? – Composable abstractions for LLM applications – Rich ecosystem of integrations – Production-ready patterns – Active community and development


Execution Flow

1. Initialize agent with configuration
   ↓
2. Load environment and dependencies
   ↓
3. Prepare prompt with input data
   ↓
4. Invoke LLM through LangChain
   ↓
5. Parse and validate response
   ↓
6. Return formatted result

Key Decision Points: – Model selection (temperature, model type) – Prompt structure (few-shot vs zero-shot) – Error handling strategy – Output format validation


Performance Considerations

Computational Cost

  • LLM Calls: Primary cost factor (based on tokens)
  • Latency: Depends on model and input size
  • Memory: Minimal for most patterns

Optimization Strategies

  1. Prompt Optimization: Minimize tokens while maintaining clarity
  2. Caching: Cache repeated queries/responses
  3. Model Selection: Use smaller models when appropriate
  4. Batch Processing: Group similar requests
  5. Streaming: For long responses, stream tokens

Cost Estimates (Approximate)

  • GPT-3.5-turbo: ~$0.002 per request
  • GPT-4: ~$0.03 per request
  • GPT-4-turbo: ~$0.01 per request

Actual costs vary based on input/output token counts


Common Pitfalls to Avoid

1. Prompt Design Issues

❌ Vague or ambiguous instructions
✅ Clear, specific, testable prompts

2. Error Handling

❌ Ignoring API errors or rate limits
✅ Implement retry logic and graceful degradation

3. Token Management

❌ Exceeding model token limits
✅ Truncate inputs, chunk processing

4. Security

❌ Exposing API keys in code
✅ Use environment variables

5. Testing

❌ Only testing happy paths
✅ Test edge cases, failures, malformed inputs

6. Cost Management

❌ Unmonitored API usage
✅ Implement budgets, alerts, and monitoring


Further Improvements

Production Enhancements

  1. Monitoring: Add logging, metrics, tracing
  2. Validation: Input/output schema validation
  3. Rate Limiting: Implement request throttling
  4. Caching: Redis or in-memory cache for responses
  5. Async Support: Non-blocking operations for scalability

Feature Extensions

  1. Multi-Model Support: Switch between providers
  2. Fallback Models: Graceful degradation strategy
  3. Custom Tools: Domain-specific function calling
  4. Advanced Memory: Vector stores for long-term memory
  5. Evaluation: Automated testing and benchmarking

Code Quality

  1. Testing: Unit tests, integration tests
  2. Documentation: API docs, usage examples
  3. Type Safety: Stricter type hints
  4. Configuration: Externalized config files

Related Patterns

  • Pattern 047
  • Pattern 049

Pattern Families: – Reasoning Patterns (001-011) – Multi-Agent Patterns (012-019) – Tool Use Patterns (020-025) – Memory Patterns (026-031) – And many more…


Summary

The Sandboxing pattern provides a powerful approach to building AI agents with specific capabilities. This implementation demonstrates:

✅ Key Strengths: – Clean, maintainable code structure – LangChain integration for composability – Type hints and documentation – Production-ready patterns

🎯 Best Use Cases: – Applications requiring this pattern’s characteristics – Systems needing structured agent behavior – Production environments requiring reliability

📚 Learning Resources: – LangChain Documentation: https://python.langchain.com/ – Pattern Documentation: See related patterns – OpenAI API Reference: https://platform.openai.com/docs/


File: 048_sandboxing.py
Total Lines: 761
Pattern Category: AI Agent Design Pattern #048


Generated from actual implementation code
For educational and reference purposes

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