API design & gRPC
REST best practices, protobuf, API versioning, and backward-compatible service contracts.
How to Build a Mock REST GET Endpoint Handler in Python
Create a lightweight mock REST GET server in Python using the standard library, with a dict-based route registry that maps paths to handler functions and returns JSON responses with proper HTTP status codes.
from http.server import BaseHTTPRequestHandler, HTTPServer
import json
# Mock API handler registry
def handle_users():
return {"status": "ok", "data": [{"id": 1, "name": "Alice"}, {"id": 2, "name": "Bob"}]}
def handle_products():
return {"status": "ok", "data": [{"id": 101, "name": "Laptop", "price": 999.99}…How to Create an RFC 7807 Error JSON in Python
Construct a structured error response using the RFC 7807 Problem Details format with a reusable function.
import json
from typing import Dict
def create_rfc7807_error(
type_: str,
title: str,
status: int,
detail: str,
instance: str,
extra_fields: Dict[str, object] | None = None,
) -> str:
"""
Build a JSON string following RFC 7807 Problem Details format.
"""
problem = {
"t…How to Implement RBAC Permission Checks with a Route Decorator in Python
Build a reusable Python decorator that checks a user's role against allowed roles and raises a custom PermissionError when access is denied.
from functools import wraps
from enum import Enum
class Role(Enum):
ADMIN = "admin"
MODERATOR = "moderator"
USER = "user"
class PermissionError(Exception):
pass
def require_role(*allowed_roles):
def decorator(func):
@wraps(func)
def wrapper(user_role, *args, **kwargs):
…How to Implement Sparse Fieldsets in Python
A function that filters API responses by resource type, returning only requested fields plus IDs, as a sparse fieldset mock.
from dataclasses import dataclass, field
from typing import Dict, List, Optional
@dataclass
class MockResponse:
data: Dict[str, object] = field(default_factory=dict)
included: List[Dict[str, object]] = field(default_factory=list)
def select_fields(
data: Dict[str, object],
sparse_fields: Optional[D…How to Implement a PATCH Partial Update Merge Dict in Python
Implements a recursive merge function that applies HTTP PATCH-like partial updates to a nested dictionary while preserving untouched fields.
import json
def patch_merge(target: dict, patch: dict) -> dict:
"""Simulate HTTP PATCH semantic: shallow-merge patch into a copy of target."""
merged = target.copy()
for key, value in patch.items():
if isinstance(value, dict) and isinstance(merged.get(key), dict):
merged[key] = patch_m…Browse by section
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API design & gRPC — Python code examples
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