Fail to uncompress zip file created by 7zip

[Brynne Taylor]

Deno 1.15.0
exit using ctrl+d or close()
> import * as fflate from './fflate.js';
undefined
> const rawdata = await Deno.readFile('county_border.zip');
undefined
> fflate.decompressSync(rawdata)
Uncaught Error: invalid length/literal
    at inflt (file:///D:/git_work/loc2district/fflate.js:259:9)
    at inflateSync (file:///D:/git_work/loc2district/fflate.js:920:10)
    at Module.decompressSync (file:///D:/git_work/loc2district/fflate.js:1201:159)
    at <anonymous>:2:8
> rawdata
Uint8Array(31903372) [
   80,  75,   3,   4,  20,   0,   0,   0,   8,   0, 101,  91,  35,  83, 175,
  100, 188, 138, 226, 205, 230,   1,  52, 251,  18,   7,  18,   0,   0,   0,
   99, 111, 117, 110, 116, 121,  95,  98, 111, 114, 100, 101, 114,  46, 106,
  115, 111, 110, 180, 157, 187, 202, 104,  61,  17, 134, 123, 175,  66, 172,
   69, 114,  78, 150, 173,  96,  41, 246,  34, 226,  25, 193,  19,  30,  10,
   17,  11,  65, 176,  17, 177, 241,  22,  44,   5,  11,  27,   5, 189,  26,
    5, 239, 194, 247, 205, 154, 201, 188, 203, 195,
  ... 31903272 more items
]

[101arrowz]

Please attach or send this file so I can investigate the issue - this output alone doesn't really provide enough information to fix the issue.

[Brynne Taylor]

airports.zip

The original file is too large for upload. I uploaded a small file which also produces this issue.

[101arrowz]

Sorry I misread your initial post. You're doing decompressSync instead of unzipSync - decompress is only for GZIP, Zlib, or DEFLATE files, while unzip is for ZIP files. So you can do this:

const archive= fflate.unzipSync(rawdata);
// For the file you sent me
const airports = archive['airports.dat'];

Let me know if that works for you.

[James Hegedus]

I found some of the docs confusing in this regard. It states in the readme

fflate can autodetect a compressed file's format as well

const compressed = new Uint8Array(
  await fetch('/GZIPorZLIBorDEFLATE').then(res => res.arrayBuffer())
);
// Above example with Node.js Buffers:
// Buffer.from('H4sIAAAAAAAAE8tIzcnJBwCGphA2BQAAAA==', 'base64');
const decompressed = fflate.decompressSync(compressed);

With this example being so early in the docs, I assumed it was the preferred way to use the library and it performed internal logic (magic) to determine which internal function to use for all types of ZIP, GZIP, Zlib & DEFLATE. Caused me a lot of confusion until I tried some of the other functions. I followed this issue assuming it was a bug given my understanding of the API.

It would help inexperienced users like myself if there was a table in the docs matching the types of files to the API/function used for those types.

[Brynne Taylor]

It works! Thank you. I'm also confused by

fflate can autodetect a compressed file's format as well

[101arrowz]

It would help inexperienced users like myself if there was a table in the docs matching the types of files to the API/function used for those types.

Thanks for the feedback, I'll close this issue after clarifying in the docs.