Cendry¶

from cendry import Model, Map, Field, field

class Mayor(Map):
    name: Field[str]
    since: Field[int]

class City(Model, collection="cities"):
    name: Field[str]
    state: Field[str]
    population: Field[int]
    mayor: Field[Mayor | None] = field(default=None)

from cendry import Cendry

with Cendry() as ctx:
    # Python operators become Firestore filters
    cities = (
        ctx.select(City)
        .filter(City.state == "CA")
        .order_by(City.population.desc())
        .limit(10)
        .to_list()
    )

    for city in cities:
        print(city.name, city.population)

from cendry import Cendry, Increment

with Cendry() as ctx:
    # Save (upsert)
    city = City(name="SF", state="CA", population=870_000)
    ctx.save(city)  # auto-generates ID

    # Partial update
    ctx.update(city, {"population": Increment(1000)})

    # Atomic batch
    with ctx.batch() as batch:
        batch.save(city1)
        batch.delete(city2)

    # Transaction with auto-retry
    def transfer(txn):
        src = txn.get(City, "SF")
        txn.update(src, {"population": src.population - 100})

    ctx.transaction(transfer)

from cendry import AsyncCendry

async with AsyncCendry() as ctx:
    city = await ctx.get(City, "SF")
    print(city.name)

    await ctx.save(city)
    await ctx.update(city, {"population": 900_000})

    async for city in ctx.select(City, City.state == "CA"):
        print(city.population)