Transform stream that gunzips its input if it is gzipped and just echoes it if not.

npm install gunzip-maybe

Simply pipe a gzipped (or not gzipped) stream to gunzip([maxRecursion = 3]) and read the unzipped content. maxRecursion protects the unzip mechanism from an infinite recursion in case of a malicious archive.

// this will gunzip gzippedStream
gzippedStream.pipe(gunzip()).pipe(process.stdout);

// this will just echo plainTextStream
plainTextStream.pipe(gunzip()).pipe(process.stdout);

npm install -g gunzip-maybe
gunzip-maybe --help # will print out usage

MIT