GenerateEmail Class — drizzle-orm Architecture

Source Code

drizzle-seed/src/services/Generators.ts lines 1823–1885

export class GenerateEmail extends AbstractGenerator<{
	arraySize?: number;
}> {
	static override readonly entityKind: string = 'GenerateEmail';

	private state: {
		genIndicesObj: GenerateUniqueInt;
		arraysToGenerateFrom: string[][];
	} | undefined;
	public override timeSpent: number = 0;
	public override isUnique = true;

	override init({ count, seed }: { count: number; seed: number }) {
		super.init({ count, seed });

		const domainsArray = emailDomains;
		const adjectivesArray = adjectives;
		const namesArray = firstNames;

		const maxUniqueEmailsNumber = adjectivesArray.length * namesArray.length * domainsArray.length;
		if (count > maxUniqueEmailsNumber) {
			throw new RangeError(
				`count exceeds max number of unique emails(${maxUniqueEmailsNumber}).`,
			);
		}

		const maxEmailLength = maxAdjectiveLength + maxFirstNameLength + maxEmailDomainLength + 2;
		if (this.stringLength !== undefined && this.stringLength < maxEmailLength) {
			throw new Error(
				`You can't use email generator with a db column length restriction of ${this.stringLength}. Set the maximum string length to at least ${maxEmailLength}.`,
			);
		}

		const arraysToGenerateFrom = [adjectivesArray, namesArray, domainsArray];
		const genIndicesObj = new GenerateUniqueInt({
			minValue: 0,
			maxValue: maxUniqueEmailsNumber - 1,
		});
		genIndicesObj.init({ count, seed });

		this.state = { genIndicesObj, arraysToGenerateFrom };
	}

	generate() {
		if (this.state === undefined) {
			throw new Error('state is not defined.');
		}

		const t0 = new Date();
		const emailIndex = this.state.genIndicesObj.generate() as number;
		this.timeSpent += (Date.now() - t0.getTime()) / 1000;
		const tokens = fastCartesianProduct(
			this.state.arraysToGenerateFrom,
			emailIndex,
		) as string[];

		const [adjective, name, domain] = [tokens[0] as string, tokens[1] as string, tokens[2] as string];

		const email = `${adjective}_${name.toLowerCase()}@${domain}`;

		return email;
	}
}