serverless-spy
Version:
CDK-based library for writing elegant integration tests on AWS serverless architecture and an additional web console to monitor events in real time.
25 lines (24 loc) • 892 B
JavaScript
import { createReadStream } from "fs";
import { HashCalculator } from "./HashCalculator";
export const fileStreamHasher = (hashCtor, fileStream) => new Promise((resolve, reject) => {
if (!isReadStream(fileStream)) {
reject(new Error("Unable to calculate hash for non-file streams."));
return;
}
const fileStreamTee = createReadStream(fileStream.path, {
start: fileStream.start,
end: fileStream.end,
});
const hash = new hashCtor();
const hashCalculator = new HashCalculator(hash);
fileStreamTee.pipe(hashCalculator);
fileStreamTee.on("error", (err) => {
hashCalculator.end();
reject(err);
});
hashCalculator.on("error", reject);
hashCalculator.on("finish", function () {
hash.digest().then(resolve).catch(reject);
});
});
const isReadStream = (stream) => typeof stream.path === "string";