API design & gRPC
REST best practices, protobuf, API versioning, and backward-compatible service contracts.
Create a Data Helper in Python for gRPC-style APIs
This code builds a simple DataHelper class that mimics gRPC request/response handling with in-memory storage, JSON serialization, and basic CRUD operations for beginners.
import json
from dataclasses import dataclass, asdict
from typing import Dict, Any
@dataclass
class User:
user_id: int
name: str
email: str
class DataHelper:
"""Simple helper to demonstrate gRPC-like data handling for beginners."""
def __init__(self) -> None:
self._users: Dict[int, Use…Generate an OpenAPI Spec from Mock Routes in Python
This Python script generates an OpenAPI 3.0 specification from a simple mock routes dictionary, mapping each HTTP method to response examples.
import json
from pathlib import Path
def generate_openapi_spec(routes: dict, title: str = "Mock API", version: str = "1.0.0") -> dict:
paths = {}
for route, methods in routes.items():
path_item = {}
for method, response_data in methods.items():
method = method.lower()
…How to Add HATEOAS Links to a Python API Response
Build a Python API resource class that adds self and next HATEOAS links to JSON responses, with a mock example for pagination.
import json
class Resource:
def __init__(self, name, data, next_page=None):
self.links = {"self": f"/api/resources/{name}"}
if next_page is not None:
self.links["next"] = f"/api/resources?page={next_page}"
self.data = data
def to_dict(self):
return {"links": self.…How to Build a Simple Filter Helper in Python for API Design
Create a reusable data filter service with dataclasses that mimics gRPC request/response patterns for filtering dataset records.
from dataclasses import dataclass, field
from typing import List, Optional, Dict, Any
@dataclass
class FilterRequest:
"""A simple filter request mirroring a gRPC message structure."""
field_name: str
operator: str # eq, ne, gt, lt, contains
value: Any
page_size: int = 10
page_token: Optional…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 Expand Related Resources with a Mock Embed in Python
Simulate API response embedding by attaching mock embedded data to each related resource in a list using a simple Python class.
import json
class EmbedMock:
def __init__(self, resources):
self.resources = resources
def expand(self):
for resource in self.resources:
resource["embedded"] = self._generate_embed()
def _generate_embed(self):
return {
"id": 1,
"type": "mock",
…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 Mock HTTP 304 Responses with If-None-Match in Python
Spin up a local HTTP server that returns a 304 Not Modified when a request carries a matching ETag, useful for testing cache behavior.
from http.server import BaseHTTPRequestHandler, HTTPServer
from threading import Thread
import urllib.request
ETAG = '"abc123"'
BODY = b'{"status": "ok"}'
class MockServer(BaseHTTPRequestHandler):
def do_GET(self):
if self.headers.get('If-None-Match') == ETAG:
self.send_response(304)
…How to Mock an API Key Header Authentication Server in Python
A minimal HTTP server that validates requests using an X-API-Key header and returns JSON responses for authenticated and unauthenticated calls.
import json
from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
API_KEYS = {"test-user": "secret-key-123"}
class AuthHandler(BaseHTTPRequestHandler):
def do_GET(self):
auth = self.headers.get("X-API-Key")
if not auth or auth not in API_KEYS.values():
self.send_response…How to Serialize a Dataclass to JSON in Python
Serialize a Python dataclass instance to JSON using asdict and json.dumps for API responses or mocks.
from dataclasses import dataclass, asdict
import json
@dataclass
class UserResponse:
id: int
name: str
email: str
active: bool = True
if __name__ == "__main__":
response = UserResponse(id=42, name="Ada Lovelace", email="ada@example.com")
print(json.dumps(asdict(response), indent=2))Browse by section
Each section groups closely related Python snippets.
API design & gRPC — Python code examples
What you will find here
This page collects api design & grpc snippets — short, copy-ready Python you can paste into our free online IDE and run without installing anything. Each sample includes a plain-English explanation and the full source code.
Samples vs tutorials and challenges
Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.