enhance(backend): improve chart engine

packages/backend/src/services/chart/charts/test-unique.ts

@@ -0,0 +1,40 @@
+import autobind from 'autobind-decorator';
+import Chart, { DeepPartial } from '../core';
+import { SchemaType } from '@/misc/schema';
+import { name, schema } from './entities/test-unique';
+
+type TestUniqueLog = SchemaType<typeof schema>;
+
+/**
+ * For testing
+ */
+// eslint-disable-next-line import/no-default-export
+export default class TestUniqueChart extends Chart<TestUniqueLog> {
+	constructor() {
+		super(name, schema);
+	}
+
+	@autobind
+	protected genNewLog(latest: TestUniqueLog): DeepPartial<TestUniqueLog> {
+		return {};
+	}
+
+	@autobind
+	protected aggregate(logs: TestUniqueLog[]): TestUniqueLog {
+		return {
+			foo: logs.reduce((a, b) => a.concat(b.foo), [] as TestUniqueLog['foo']),
+		};
+	}
+
+	@autobind
+	protected async fetchActual(): Promise<DeepPartial<TestUniqueLog>> {
+		return {};
+	}
+
+	@autobind
+	public async uniqueIncrement(key: string): Promise<void> {
+		await this.inc({
+			foo: [key],
+		});
+	}
+}