A cache-based python ORM -- supports Redis/Memcached/InMemory/FileSystem backends, and JSON/Msgpack/Pickle/Protobuf serializers.

CacheBackend

• BaseBackend
• SimpleBackend
• RedisBackend
• MemcachedBackend
• TODO: FileSystemBackend

Methods

• set(key, value)
• replace(key, value)
• get(key)
• delete(key)
• set_many(mapping)
• replace_many(mapping)
• get_many(*keys)
• delete_many(*keys)
• has(key)
• incr/decr(key, delta)
• TODO: add(key value): Store this data, only if it does not already exist.

Serializer

• JSON
• Msgpack
• Pickle
• Protobuf

Registry

All serializers are registered to a registry singleton. Provide json, msgpack, pickle three preset serializers.

You can register your own serializer, such as a Protobuf serializer with a User message.

import cacheorm as co

co.registry.register("protobuf.user", co.ProtobufSerializer(user_pb2.User))

Model

Declare

import datetime

import cacheorm as co

class User(co.Model):
    id = co.IntegerField(primary_key=True)
    name = co.StringField()
    height = co.FloatField()
    married = co.BooleanField(default=False)
    gender = co.EnumField(Gender, default=Gender.UNKNOWN)
    phones = co.ListField(co.StructField(PhoneNumber.se, PhoneNumber.de), default=[])
    created_at = co.DateTimeTZField(
        default=partial(datetime.datetime.now, tz=datetime.timezone.utc)
    )

    class Meta:
        backend = co.RedisBackend()
        serializer = "json"


class Article(co.Model):
    id = co.IntegerField(primary_key=True)
    author = co.ForeignKeyField(User)
    title = co.StringField()
    content = co.StringField(default="")
    created_at = co.DateTimeField(default=datetime.datetime.now)
    updated_at = co.DateTimeField(default=datetime.datetime.now)

    class Meta:
        backend = co.SimpleBackend()
        serializer = "protobuf.article"
        ttl = 100 * 24 * 3600


class Collection(co.Model):
    collector = co.ForeignKeyField(User)
    article = co.ForeignKeyField(Article)
    mark = co.StringField(default="")

    class Meta:
        primary_key = co.CompositeKey("collector", "article", index_formatter="collection.%s.%d")
        backend = co.MemcachedBackend()
        serializer = "msgpack"

Meta

• primary_key
• backend
• serializer
• ttl

Insert

sam = User.create(id=1, name="Sam", height=178.8, gender=Gender.MALE)
bob = User.insert(id=2, name="Bob", height=182.4, gender=Gender.MALE).execute()
article = Article(author=sam, title="CacheORM", content="Create a article using cacheorm.")
article.save(force_insert=True)
collections = Collection.insert_many(
    {"collector": bob, "article_id": article},
    Collection(collector=sam, article=article)
).execute()

Query

sam = User.get(id=1)
bob = User.get_by_id(2)
article = Article.query(id=1).execute()
collections = Collection.query_many(
    {"collector_id": 1, "article_id": article.id},
    {"collector": bob, "article_id": article.id},
).execute()

Update

Like insert, but only update field values when key exists. Support for updating partial field values.

Note that the Cache Backend is not atomic for update operations, so if you want to guarantee atomicity, you need manager lock by yourself, such as with redlock.

sam = User.set_by_id(1, {"height": 178.0})
bob = User.get_by_id(2)
bob.married = True
bob.save()
article = Article.update(
    id=1, title="What's new in CacheORM?"
).execute()
collections = Collection.update_many(
    {"collector_id": 1, "article_id": article.id, "mark": "mark"},
    {"collector": bob, "article_id": article.id, "mark": "Good"},
).execute()

Delete

User.delete_by_id(2)
User.delete(id=1).execute()
article = Article.query(id=1).execute()
Collection.delete_many(
    {"collector_id": 1, "article_id": article.id},
    {"collector_id": 2, "article_id": article.id},
).execute()
article.delete_instance()

ModelHelper

Insert

Query

Update

Delete

Fields

• UUIDField/ShortUUIDField
• IntegerField
• EnumField
• BooleanField
• FloatField
• DecimalField
• StringField
• BinaryField
• DateTimeField
• DateField
• TimeField
• TimestampField
• StructField(serializer, deserializer)
• JSONField
• ForeignKeyField
• CompositeKey

TODO LIST

Signals

• pre_save
• post_save
• pre_delete
• post_delete

Compatible payload

• support changeable serializer

ModelHelper

• preload foreign model instance
• insert many different model instances

Bench

• MEM bench
• QPS bench

Docs

• methods docstring
• Quick start