app.py

from contextlib import asynccontextmanager
from functools import partial
from pathlib import Path

import httpx
from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from florapi import utc_now
from florapi.configuration import Options
from florapi.middleware import ProxyHeadersMiddleware, TimedLogMiddleware
from florapi.security import RateLimiter
from florapi.sqlite import open_sqlite_connection, register_adaptors

THIS_DIR = Path(__file__).parent
GRAPHQL_API = "https://api.github.com/graphql"
# This query was originally written by Jakub Kuczys (GitHub: @Jackenmen) who graciously
# gave me permission to use his work freely here.
GRAPHQL_QUERY = """
query getLastIssueNumber {
  repository(owner: "$owner", name: "$name") {
    discussions(orderBy: {field: CREATED_AT, direction: DESC}, first: 1) {
      nodes {
        number
      }
    }
    issues(orderBy: {field: CREATED_AT, direction: DESC}, first: 1) {
      nodes {
        number
      }
    }
    pullRequests(orderBy: {field: CREATED_AT, direction: DESC}, first: 1) {
      nodes {
        number
      }
    }
  }
}
"""
opt = Options()
GITHUB_TOKEN = opt("github-token", type=str)
DATABASE_PATH = opt("database", default=THIS_DIR / "db.sqlite3", type=Path)
opt.report_errors()

register_adaptors()
open_sqlite_connection = partial(open_sqlite_connection, DATABASE_PATH)


@asynccontextmanager
async def lifespan(app: FastAPI):
    yield
    await http.aclose()


app = FastAPI(lifespan=lifespan)
app.add_middleware(
    CORSMiddleware,
    allow_origins=["https://ichard26.github.io"],
    allow_methods=["GET"],
)
app.add_middleware(ProxyHeadersMiddleware)
app.add_middleware(TimedLogMiddleware, sqlite_factory=open_sqlite_connection)
http = httpx.AsyncClient()


@app.get("/")
async def get_next_number(owner: str, name: str) -> int:
    db = open_sqlite_connection()
    limiter = RateLimiter("api", {RateLimiter.HOUR: 25, RateLimiter.DAY: 100}, db)
    if limiter.update_and_check("query"):
        raise HTTPException(429, "API rate limit exceeded")

    query = GRAPHQL_QUERY.replace("$owner", owner).replace("$name", name)
    response = await http.post(
        GRAPHQL_API, json={"query": query}, headers={"Authorization": f"Bearer {GITHUB_TOKEN}"}
    )
    repository_data = response.json()["data"]["repository"]
    if repository_data is None:
        raise HTTPException(404, "repository not found")

    # These four lines were originally written by Jakub Kuczys (GitHub: @Jackenmen) who
    # graciously gave me permission to use his work freely here.
    current_number = max(
        next(iter(data["nodes"]), {"number": 0})["number"]
        for data in repository_data.values()
    )
    db.insert("queries", {
        "datetime": utc_now(),
        "owner": owner,
        "name": name,
        "result": current_number + 1
    })
    db.commit()
    return current_number + 1