25 lines
892 B
JavaScript
25 lines
892 B
JavaScript
import { createReadStream } from "fs";
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import { HashCalculator } from "./HashCalculator";
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export const fileStreamHasher = (hashCtor, fileStream) => new Promise((resolve, reject) => {
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if (!isReadStream(fileStream)) {
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reject(new Error("Unable to calculate hash for non-file streams."));
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return;
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}
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const fileStreamTee = createReadStream(fileStream.path, {
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start: fileStream.start,
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end: fileStream.end,
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});
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const hash = new hashCtor();
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const hashCalculator = new HashCalculator(hash);
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fileStreamTee.pipe(hashCalculator);
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fileStreamTee.on("error", (err) => {
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hashCalculator.end();
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reject(err);
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});
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hashCalculator.on("error", reject);
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hashCalculator.on("finish", function () {
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hash.digest().then(resolve).catch(reject);
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});
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});
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const isReadStream = (stream) => typeof stream.path === "string";
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