blog/lib/hash.ts

52 lines
1.5 KiB
TypeScript

import { createHash } from "node:crypto";
import { PRODUCTION } from "./environment.ts";
import { Observable } from "rxjs";
import { Buffer } from "node:buffer";
import { VFile } from "vfile";
function fileHash(buffer: Buffer) {
const hash = createHash("sha256");
hash.update(buffer.toString());
return hash.digest("hex");
}
const hashPath = (mappings: Map<string, string>) => (file: VFile): VFile => {
const hash = PRODUCTION ? fileHash(file.value) : "00000000";
const newName = [
file.stem!,
hash.substring(0, 8),
file.extname!.substring(1),
].join(".");
mappings.set(file.basename!, newName);
file.basename = newName;
return file;
};
export default function (manifestName: string) {
return (observable: Observable<VFile>): Observable<VFile> =>
new Observable((subscriber) => {
const mappings = new Map<string, string>();
const hash = hashPath(mappings);
observable.subscribe({
next(file) {
subscriber.next(hash(file));
},
error(e) {
subscriber.error(e);
},
complete() {
const mappingFile = new VFile({
path: manifestName,
value: JSON.stringify(Object.fromEntries(mappings)),
});
subscriber.next(mappingFile);
subscriber.complete();
},
});
});
}