orm-redis
v0.1.10
Published
ORM Like Redis mapper for Typescript
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Readme
Redis ORM for TypeScript
Features:
- Modern ORM based on decorators & datamapper pattern
- Type binding for numbers, booleans, strings, dates. Objects/arrays are being converted to json strings
- Native support for ES2015 Maps and Sets (Stored as separated hashes/sets in Redis)
- Single field relation support
- Multiple relations support for Maps and Sets
- Relations cascade inserting/updating (But not deleting)
- Entity subscriber support & built-in pubsub subscriber
- Operation optimized - writes to redis only changed values
- Lazy maps/sets support
- Optimistic locking (WIP)
Requirments
- TypeScript 2.3 or greater
- Node 7.*
- Symbol.asyncIterator polyfill to iterate over lazy maps/sets
Setup
Enable emitDecoratorMetadata
and experimentalDecorators
in your tsconfig.json
Install reflect-metadata
library and import it somewhere in your project:
npm install reflect-metadata --save
// in index.ts
import "reflect-metadata";
If you're going to use lazy maps/sets then you need Symbol.asyncIterator
polyfill. This can be easily achived by writing this somewhere in app:
(Symbol as any).asyncIterator = (Symbol as any).asyncIterator || Symbol.for("Symbol.asyncIterator");
Examples
Basic example
import { createConnection, Entity, Property, IdentifyProperty } from "orm-redis";
@Entity()
class MyEntity {
// You must have one identify property. Supported only string and numbers
@IdentifyProperty()
public id: number;
@Property()
public myString: string;
@Property()
public myNumber: number;
@Property()
public myDate: Date;
@Property()
public myObj: object; // will be stored in json
@Property(Set)
public mySet: Set<any> = new Set(); // uses redis sets
@Property(Map)
public myMap: Map<any, any> = new Map(); // uses redis maps
}
createConnection({
host: process.env.REDIS_HOST,
port: process.env.REDIS_PORT
}).then(async connection => {
const entity = new MyEntity();
entity.id = 1;
entity.myString = "abc";
entity.myNumber = 1;
entity.myDate = new Date();
// 1 and "1" keys are different for sets and maps
entity.mySet.add(1).add("1");
entity.myMap.set(1, true).set("1", false);
await connection.manager.save(entity);
// Load entity
const stored = await connection.manager.load(MyEntity, 1):
stored.id; // 1
stored.myDate; // Date object
stored.myMap; // Map { 1: true, "1": false }
stored.mySet; // Set [ 1, "1" ]
stored.myMap.delete(1);
stored.myMap.set(3, "test");
stored.myNumber = 10;
// Save changes. Will trigger persistence operation only for changed keys
await connection.manager.save(stored);
// Delete
await connection.manager.delete(stored);
}).catch(console.error);
Relations
ORM supports both single relations (linked to a single property) and multiple relations (linked to Set/Map)
@Entity()
class Relation {
@IdentifyProperty()
public id: number;
@Property()
public relProp: string;
}
@Entity()
class Owner {
@IdentifyProperty()
public id: string;
@RelationProperty(type => Relation, { cascadeInsert: true, cascadeUpdate: true })
public rel: Relation;
@RelationProperty(type => [Relation, Set], { cascadeInsert: true })
public relationSet: Set<Relation> = new Set();
@RelationProperty(type => [Relation, Map], { cascadeInsert: true })
public relationMap: Map<number, Relation> = new Map();
}
const rel1 = new Relation();
rel1.id = 1;
const rel2 = new Relation();
rel2.id = 2;
const owner = new Owner();
owner.id = "test";
owner.rel = rel1;
owner.relationSet.add(rel1);
owner.relationMap.set(10, rel1);
owner.relationMap.set(12, rel2);
// Cascading insert will save all relations too in object
await manager.save(owner);
// Get and eager load all relations, including all inner relations (if presented)
const loaded = await manager.load(Owner, "test");
loaded.rel.relProp = "test";
// If cascadeUpdate was set then will trigger update operation for Relation entity
await manager.save(loaded);
// Don't load relations for properties rel and relationMap
const another = await manager.load(Owner, "test", /* skip relations */ ["rel", "relationMap"]);
NOTE: ORM DOESN'T support cascade delete operation now, you must delete your relations manually
@Entity()
class Relation {
@IdentifyProperty()
public id: number;
}
@Entity()
class Owner {
@IdentifyProperty()
public id: number;
@RelationProperty(type => [Relation, Set])
public setRel: Set<Relation> = new Set();
}
// To clean owner object with all linked relations:
const owner = await manager.load(Owner, 1);
for (const rel of owner.setRel) {
await manager.delete(rel);
}
await manager.delete(owner);
Lazy collections
By default all sets/maps are being loaded eagerly. If your map/set in redis is very big, it can take some time to load, especially for relation sets/maps. You can use lazy sets/maps in this case:
import { LazySet, LazyMap } from "orm-redis";
@Entity()
class Ent {
@IdentifyProperty()
public id: number;
@Property()
public set: LazySet<any> = new LazySet();
@Property()
public map: LazyMap<any, any> = new LazyMap()
}
const ent = new Ent();
ent.id = 1;
// Won't be saved until calling manager.save() for new entities
await ent.set.add(1);
await ent.map.set(1, true);
await manager.save(ent);
// Immediately saved to set in redis now
await ent.set.add(2);
// Use asyncronyous iterator available in TS 2.3+
for await (const v of ent.set.values()) {
// do something with v
}
console.log(await ent.set.size()); // 2
const anotherEnt = await manager.load(Ent, 2);
for await (const [key, val] of anotherEnt.map.keysAndValues()) {
// [1, true]
}
@Entity()
class Rel {
@IdentifyProperty()
public id: number;
}
@Entity()
class AnotherEnt {
@IdentifyProperty()
public id: number;
@RelationProperty(type => [Rel, LazyMap], { cascadeInsert: true }) // same rules as for ordinary relation map/set for cascading ops
public map: LazyMap<number, Rel> = new LazyMap()
}
const rel = new Rel();
rel.id = 1;
const anotherEnt = new AnotherEnt();
anotherEnt.id = 1;
anotherEnt.map.set(1, rel);
await manager.save(anotherEnt);
const savedEnt = await manager.load(AnotherEnt, 1);
await savedEnt.map.get(1); // Rel { id: 1 }
Asyncronyous iterators are using SCAN
redis command so they suitable for iterating over big collections.
LazyMap/LazySet after saving entity/loading entity are being converted to specialized RedisLazyMap/RedisLazySet.
Also it's possible to use RedisLazyMap/RedisLazySet directly:
const map = new RedisLazyMap(/* redis map id */"someMapId", /* redis manager */ connection.manager);
await map.set(1, true);
await map.set(2, false);
for await (const [key, val] of map.keysAndValues()) {
// [1, true], [2, false]
}