How can I compress JSON and uncompress on PHP?

Question

BTW, this is not a duplicate, I'm not trying to compress in PHP, I'm trying to compress Client Side and uncompress in PHP.

I'm trying to compress a JSON array containing 5 base64 images and some text to my PHP api.

I have tried lz-string and pako and it appears to be sending the compressed payload as expected but I'm having issues decompressing on the PHP backend.

Typescript Gzip.

  var payload = pako.gzip(JSON.stringify(data), { to: 'string' });

  let headers = new Headers({ "Content-Encoding" : "gzip"});
  headers.append('Content-Type', 'application/json; charset=x-user-defined-binary');
  let requestOptions = new RequestOptions({ headers: headers });

  var url = this.baseUrl + "/app/notice/issue/compressed";
  return this.http.post(url, data, requestOptions).pipe(timeout(100000), map(res => { return res.json() }), catchError(err => { return throwError(err.message); }));

PHP

$input = file_get_contents("php://input");
$test = gzdecode($input);
echo $test;

Output

"

<div style="border:1px solid #990000;padding-left:20px;margin:0 0 10px 0;">

<h4>A PHP Error was encountered</h4>

<p>Severity: Warning</p>
<p>Message:  gzdecode(): data error</p>


</div>"

If anyone can help in reducing the size of my JSON, that would be really helpful.

Thanks.

refer to this, though it is java will point you in the right direction https://stackoverflow.com/a/1407637/5956589 also check out the other others referring to the php uncompressing part — Richard Muvirimi, Jun 09 '20 at 17:19

alex · Answer 1 · 2019-07-30T11:01:07.107

0

You PHP exapmle looks fine and should work.

I'm not sure about the Typescript part: binary string can be additionaly encoded (as UTF-8 maybe?) before being sent by browser or http.post() method.

Check sent Content-Length of the request and actual length of the binary string after compression. They obviously must be the same.

I suggest removing {to: 'string'} option in pako.gzip() method to get Uint8Array instead of string and use XMLHttpRequest instead of http.post()

How can I compress JSON and uncompress on PHP?

1 Answers1