Skip to content

feat: add snapshot #201

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
CorentinDoue wants to merge 1 commit into
base: main
Choose a base branch
from
Draft

feat: add snapshot #201

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
79 changes: 76 additions & 3 deletions packages/core/src/eventStore/eventStore.fixtures.test.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,6 +5,11 @@ import { EventType, EventTypeDetail } from '~/event/eventType';
import { GroupedEvent } from '~/event/groupedEvent';
import { EventStorageAdapter } from '~/eventStorageAdapter';
import { EventStore } from '~/eventStore';
import {
cleanUpLastSnapshot,
createShouldSaveForRecurentSnapshots,
SnapshotStorageAdapter,
} from '~/snapshot';

export const pushEventMock = vi.fn();
export const pushEventGroupMock = vi.fn();
Expand Down Expand Up @@ -65,12 +70,16 @@ export const pikachuCaughtEvent: PokemonEventDetails = {
type: 'POKEMON_CAUGHT',
timestamp: '2023',
};
export const pikachuLeveledUpEvent: PokemonEventDetails = {
export const getPikachuLeveledUpEvent = (
version: number,
): PokemonEventDetails => ({
aggregateId: pikachuId,
version: 3,
version,
type: 'POKEMON_LEVELED_UP',
timestamp: '2024',
};
});
export const pikachuLeveledUpEvent = getPikachuLeveledUpEvent(3);

export const pikachuEventsMocks = [
pikachuAppearedEvent,
pikachuCaughtEvent,
Expand Down Expand Up @@ -116,3 +125,67 @@ export const pokemonsEventStore = new EventStore({
reducer: pokemonsReducer,
eventStorageAdapter: eventStorageAdapterMock,
});

export const getSnapshotMock = vi.fn();
export const saveSnapshotMock = vi.fn();
export const deleteSnapshotMock = vi.fn();

export const snapshotStorageAdapter: SnapshotStorageAdapter = {
getSnapshot: getSnapshotMock,
saveSnapshot: saveSnapshotMock,
deleteSnapshot: deleteSnapshotMock,
};

export const pikachuMultipleLevelUpEvents1Mocks = [
getPikachuLeveledUpEvent(4),
getPikachuLeveledUpEvent(5),
];
export const pikachuMultipleLevelUpEvents2Mocks = [
getPikachuLeveledUpEvent(6),
getPikachuLeveledUpEvent(7),
getPikachuLeveledUpEvent(8),
getPikachuLeveledUpEvent(9),
getPikachuLeveledUpEvent(10),
];
export const pikachuCompleteEventsMocks = [
...pikachuEventsMocks,
...pikachuMultipleLevelUpEvents1Mocks,
...pikachuMultipleLevelUpEvents2Mocks,
];

export const snapshotV5 = {
aggregate: {
aggregateId: pikachuId,
version: 5,
name: 'Pikachu',
level: 45,
status: 'caught',
},
reducerVersion: 'v1.0.0',
eventStoreId: 'POKEMONS',
};

export const snapshotV10 = {
aggregate: {
aggregateId: pikachuId,
version: 10,
name: 'Pikachu',
level: 50,
status: 'caught',
},
reducerVersion: 'v1.0.0',
eventStoreId: 'POKEMONS',
};

export const pokemonsEventStoreWithSnapshot = new EventStore({
eventStoreId: 'POKEMONS',
eventTypes: [pokemonAppearedEvent, pokemonCaughtEvent, pokemonLeveledUpEvent],
reducer: pokemonsReducer,
eventStorageAdapter: eventStorageAdapterMock,
snapshotConfig: {
currentReducerVersion: 'v1.0.0',
shouldSaveSnapshot: createShouldSaveForRecurentSnapshots(5),
cleanUpAfterSnapshotSave: cleanUpLastSnapshot,
},
snapshotStorageAdapter,
});
125 changes: 120 additions & 5 deletions packages/core/src/eventStore/eventStore.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4,11 +4,12 @@ import type { EventDetail } from '~/event/eventDetail';
import type { EventType, EventTypeDetails } from '~/event/eventType';
import { GroupedEvent } from '~/event/groupedEvent';
import type { EventStorageAdapter } from '~/eventStorageAdapter';
import { SnapshotConfig, Snapshot, SnapshotStorageAdapter } from '~/snapshot';
import type { $Contravariant } from '~/utils';

import { AggregateNotFoundError } from './errors/aggregateNotFound';
import { UndefinedEventStorageAdapterError } from './errors/undefinedEventStorageAdapter';
import type {
import {
AggregateIdsLister,
EventPusher,
OnEventPushed,
Expand All @@ -20,6 +21,8 @@ import type {
AggregateGetter,
AggregateSimulator,
Reducer,
AggregateAsSnapshotSaver,
SnapshotGetter,
} from './types';

export class EventStore<
Expand Down Expand Up @@ -139,6 +142,11 @@ export class EventStore<
eventStorageAdapter?: EventStorageAdapter;
getEventStorageAdapter: () => EventStorageAdapter;

snapshotConfig?: SnapshotConfig<AGGREGATE, $AGGREGATE>;
snapshotStorageAdapter?: SnapshotStorageAdapter<AGGREGATE, $AGGREGATE>;
getSnapshot: SnapshotGetter<AGGREGATE>;
saveAggregateAsSnapshot: AggregateAsSnapshotSaver<$AGGREGATE>;

constructor({
eventStoreId,
eventTypes,
Expand All @@ -149,20 +157,26 @@ export class EventStore<
}),
onEventPushed,
eventStorageAdapter,
snapshotConfig,
snapshotStorageAdapter,
}: {
eventStoreId: EVENT_STORE_ID;
eventTypes: EVENT_TYPES;
reducer: REDUCER;
simulateSideEffect?: SideEffectsSimulator<EVENT_DETAILS, $EVENT_DETAILS>;
onEventPushed?: OnEventPushed<$EVENT_DETAILS, $AGGREGATE>;
eventStorageAdapter?: EventStorageAdapter;
snapshotConfig?: SnapshotConfig<AGGREGATE, $AGGREGATE>;
snapshotStorageAdapter?: SnapshotStorageAdapter<AGGREGATE, $AGGREGATE>;
}) {
this.eventStoreId = eventStoreId;
this.eventTypes = eventTypes;
this.reducer = reducer;
this.simulateSideEffect = simulateSideEffect;
this.onEventPushed = onEventPushed;
this.eventStorageAdapter = eventStorageAdapter;
this.snapshotConfig = snapshotConfig;
this.snapshotStorageAdapter = snapshotStorageAdapter;

this.getEventStorageAdapter = () => {
if (this.eventStorageAdapter === undefined) {
Expand Down Expand Up @@ -239,15 +253,116 @@ export class EventStore<
this.buildAggregate = (eventDetails, aggregate) =>
eventDetails.reduce(this.reducer, aggregate) as AGGREGATE | undefined;

this.getAggregate = async (aggregateId, { maxVersion } = {}) => {
const { events } = await this.getEvents(aggregateId, { maxVersion });
this.getSnapshot = async (aggregateId, { maxVersion } = {}) => {
if (this.snapshotConfig === undefined) {
throw new Error(
`snapshotConfig is required in eventStore "${this.eventStoreId}" to use getAggregateFromSnapshot`,
);
}
if (this.snapshotStorageAdapter === undefined) {
throw new Error(
`EventStore "${this.eventStoreId}" has a snapshotConfig but no snapshotStorageAdapter.`,
);
}
const latestSnapshot = await this.snapshotStorageAdapter.getSnapshot({
aggregateId,
aggregateMaxVersion: maxVersion,
eventStoreId: this.eventStoreId,
reducerVersion:
this.snapshotConfig.migrateSnapshotReducerVersion === undefined
? this.snapshotConfig.currentReducerVersion
: undefined,
});

if (latestSnapshot === undefined) {
return undefined;
}

if (
latestSnapshot.reducerVersion ===
this.snapshotConfig.currentReducerVersion
) {
return latestSnapshot;
}

if (this.snapshotConfig.migrateSnapshotReducerVersion === undefined) {
throw new Error(
`snapshotStorageAdapter of eventStore "${this.eventStoreId}" returned a snapshot with a reducerVersion ("${latestSnapshot.reducerVersion}") different from the currentReducerVersion ("${this.snapshotConfig.currentReducerVersion}"). This is not supposed to happen`,
);
}

return this.snapshotConfig.migrateSnapshotReducerVersion(
latestSnapshot as unknown as Snapshot<$AGGREGATE>,
);
};

this.saveAggregateAsSnapshot = async (aggregate, previousSnapshot) => {
if (this.snapshotConfig === undefined) {
throw new Error(
`snapshotConfig is required in eventStore "${this.eventStoreId}" to use saveAggregateAsSnapshot`,
);
}
if (this.snapshotStorageAdapter === undefined) {
throw new Error(
`EventStore "${this.eventStoreId}" has a snapshotConfig but no snapshotStorageAdapter.`,
);
}

const snapshot = {
aggregate,
eventStoreId: this.eventStoreId,
reducerVersion: this.snapshotConfig.currentReducerVersion,
};

await this.snapshotStorageAdapter.saveSnapshot(snapshot);

await this.snapshotConfig.cleanUpAfterSnapshotSave?.({
latestSnapshot: snapshot,
previousSnapshot,
snapshotStorageAdapter: this
.snapshotStorageAdapter as unknown as SnapshotStorageAdapter<
$AGGREGATE,
$AGGREGATE
>,
});
};

this.getAggregate = async (
aggregateId,
{ maxVersion, useSnapshot } = {},
) => {
const snapshot =
useSnapshot === true
? await this.getSnapshot(aggregateId, { maxVersion })
: undefined;
const minVersion =
snapshot !== undefined ? snapshot.aggregate.version + 1 : undefined;

const { events } = await this.getEvents(aggregateId, {
maxVersion,
minVersion,
});

const aggregate = this.buildAggregate(
events as unknown as $EVENT_DETAILS[],
undefined,
snapshot?.aggregate as unknown as $AGGREGATE | undefined,
);

const lastEvent = events[events.length - 1];
if (
aggregate !== undefined &&
this.snapshotConfig?.shouldSaveSnapshot({
aggregate: aggregate as unknown as $AGGREGATE | undefined,
previousSnapshot: snapshot as Snapshot<$AGGREGATE> | undefined,
}) === true
) {
await this.saveAggregateAsSnapshot(
aggregate as unknown as $AGGREGATE,
snapshot as Snapshot<$AGGREGATE> | undefined,
);
}

const lastEvent =
events.length > 0 ? events[events.length - 1] : undefined;

return { aggregate, events, lastEvent };
};
Expand Down
98 changes: 98 additions & 0 deletions packages/core/src/eventStore/eventStore.unit.test.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -22,6 +22,15 @@ import {
groupEventMock,
eventStorageAdapterMock,
PokemonEventDetails,
pokemonsEventStoreWithSnapshot,
getSnapshotMock,
snapshotV5,
saveSnapshotMock,
deleteSnapshotMock,
snapshotV10,
pikachuMultipleLevelUpEventsMocks,
pikachuCompleteEventsMocks,
pikachuMultipleLevelUpEvents2Mocks,
} from './eventStore.fixtures.test';

describe('event store', () => {
Expand Down Expand Up @@ -51,6 +60,10 @@ describe('event store', () => {
'getAggregate',
'getExistingAggregate',
'simulateAggregate',
'snapshotConfig',
'snapshotStorageAdapter',
'getSnapshot',
'saveAggregateAsSnapshot',
]),
);

Expand Down Expand Up @@ -392,4 +405,89 @@ describe('event store', () => {
expect(response).toStrictEqual({ aggregateIds: [pikachuId] });
});
});

describe('snapshots', () => {
beforeEach(() => {
getEventsMock.mockResolvedValue({
events: pikachuMultipleLevelUpEvents2Mocks,
});
getSnapshotMock.mockClear();
getSnapshotMock.mockResolvedValue(snapshotV5);
saveSnapshotMock.mockClear();
deleteSnapshotMock.mockClear();
});
describe('getAggregate', () => {
it('gets the latest snapshot', async () => {
await pokemonsEventStoreWithSnapshot.getAggregate(pikachuId, {
useSnapshot: true,
});

expect(getSnapshotMock).toHaveBeenCalledOnce();
expect(getSnapshotMock).toHaveBeenCalledWith({
aggregateId: pikachuId,
eventStoreId: 'POKEMONS',
reducerVersion: 'v1.0.0',
});
});

it('gets events from the latest snapshot', async () => {
await pokemonsEventStoreWithSnapshot.getAggregate(pikachuId, {
useSnapshot: true,
});

expect(getEventsMock).toHaveBeenCalledTimes(1);
expect(getEventsMock).toHaveBeenCalledWith(
pikachuId,
{ eventStoreId: pokemonsEventStore.eventStoreId },
{
minVersion: 6,
},
);
});

it('saves a new snapshot', async () => {
await pokemonsEventStoreWithSnapshot.getAggregate(pikachuId, {
useSnapshot: true,
});

expect(saveSnapshotMock).toHaveBeenCalledTimes(1);
expect(saveSnapshotMock).toHaveBeenCalledWith(snapshotV10);
});

it('deletes the old snapshot', async () => {
await pokemonsEventStoreWithSnapshot.getAggregate(pikachuId, {
useSnapshot: true,
});

expect(deleteSnapshotMock).toHaveBeenCalledTimes(1);
expect(deleteSnapshotMock).toHaveBeenCalledWith({
aggregateId: 'pikachuId',
aggregateVersion: 5,
eventStoreId: 'POKEMONS',
reducerVersion: 'v1.0.0',
});
});

it('returns the aggregate from the snapshot and the rest of the events', async () => {
const response = await pokemonsEventStoreWithSnapshot.getAggregate(
pikachuId,
{
useSnapshot: true,
},
);

expect(response).toStrictEqual({
aggregate: pikachuCompleteEventsMocks.reduce(
pokemonsReducer,
undefined as unknown as PokemonAggregate,
),
events: pikachuMultipleLevelUpEvents2Mocks, // events are incomplete
lastEvent:
pikachuMultipleLevelUpEvents2Mocks[
pikachuMultipleLevelUpEvents2Mocks.length - 1
],
});
});
});
});
});
Loading
Loading