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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
import fs from "fs";
import path from "path";
import crypto from "crypto";
import flatmap from "flatmap";
// Compute the SHA-256 digest.
function sha256(data) {
let hash = crypto.createHash("sha256");
hash.update(data);
return hash.digest("hex");
}
// Recursively collect a list of all files of a given directory.
function collectFilesInDirectory(dir) {
if (fs.lstatSync(dir).isFile()) {
return [dir];
}
return flatmap(fs.readdirSync(dir), entry => {
let entry_path = path.join(dir, entry);
if (fs.lstatSync(entry_path).isDirectory()) {
return collectFilesInDirectory(entry_path);
}
return [entry_path];
});
}
// A list of hashes for each file in the given path.
function collectFileHashes(context_path) {
let root = path.join(__dirname, "../../../..");
let dir = path.join(root, context_path);
let files = collectFilesInDirectory(dir).sort();
return files.map(file => {
return sha256(file + "|" + fs.readFileSync(file, "utf-8"));
});
}
// Compute a context hash for the given context path.
export default function (context_path) {
// Regenerate when image_builder.js changes
let hashes = collectFileHashes("automation/taskcluster/graph/src/image_builder.js");
// Regenerate images when the image itself changes.
hashes = hashes.concat(collectFileHashes(context_path));
// Generate a new prefix every month to ensure the image stays buildable.
let now = new Date();
let prefix = `${now.getUTCFullYear()}-${now.getUTCMonth() + 1}:`;
return sha256(prefix + hashes.join(","));
}