convert stream to PDF - php

Question

I have a stream document I think and I need to convert it into a PDF.
The idea is to save that stream it in server as a PDF
My code :
$responce = $this->getDocumentContent();//this function returns me the $responce content bellow.
$documentFolder = $this->getDirectory().'/document/'; //var/www/project/document/
$documentFullPath = $this->getDirectory().'/document/file1.pdf';
$this->_io->mkdir($documentFolder, 0775);//create folder var/www/project/document
$document = fopen($documentFullPath, "w+");//create pdf file var/www/project/document/file1.pdf
fwrite($document, $responce);
fclose($document);
Now with this code, I create well the file1.pdf in var/www/project/document/file1.pdf but it is empty !, there is no content, the file1.pdf weight is not 0 but 163.2 Ko but I see anything. I don't know where is the issue.
$responce =
string(163146) "%PDF-1.4
%????
1 0 obj
<<
/Type /Catalog
/Pages 2 0 R
/Metadata 63 0 R
>>
endobj
2 0 obj
<<
/Type /Pages
/Kids [ 01 0 R 8 0 R ]
/Count 2
/MediaBox [ 0 0 618 003 ]
>>
endobj
3 0 obj
<<
/ModDate (D:20190907120701+02'00')
/CreationDate (D:20130904150701+02'00')
/Title (F:/Data/Composer/0510.IN.PDF)
/Subject (NONE)
/Author (User: Windows XP/ User)
/Creator (PDF/PReS Version: 6.1.1 )
/Producer ([ClibPDF Library 2.02-r1-2] Windows XP)
>>
endobj
5 0 obj
<<
/Type /Page
/Parent 2 0 R
/Resources << /Font << /Fcpdf0 30 0 R >> /XObject << /6p 8 0 R >> /ProcSet 7 0 R >>
/MediaBox [ 0 0 595 842 ]
/CropBox [ 0 0 595 842 ]
/Rotate 0
/Contents 6 0 R
>>
endobj
6 0 obj
<< /Length 246 /Filter [ /FlateDecode ] >>
stream
x??QMk?#?'1?bia=?!?L6I7?V??AB??AQ(???_:?T?"$;<vf??7?I??c?(?(?????F??4?E?<L?ku????xs???w*??
??FGD?AlY?{,???E??-A????u?o?/^^O%|??>???\?T?Y
??iS??5q?t?C2I??q???c>?V?z?8:??C??#???p/?\???0F)k#?1???U?`Sa?????.???PyoY
endstream
endobj
7 0 obj
[
/PDF /Text /ImageC
]
endobj
8 0 obj
<< /Type /XObject /BBox [ 0 0 595 842 ] /Filter /FlateDecode /FormType 1
/Length 17871 /Matrix [ 1 0 0 1 0 0 ] /Resources << /ColorSpace << /CS0 27 0 R /CS1 26 0 R /CS10 27 0 R /CS11 26 0 R /CS12 27 0 R /CS13 26 0 R
/CS14 29 0 R /CS15 28 0 R /CS16 29 0 R /CS17 28 0 R /CS18 29 0 R
/CS19 28 0 R /CS2 27 0 R /CS20 29 0 R /CS21 28 0 R /CS22 29 0 R
/CS23 28 0 R /CS24 29 0 R /CS25 28 0 R /CS26 29 0 R /CS27 28 0 R
/CS28 29 0 R /CS29 28 0 R /CS3 26 0 R /CS30 29 0 R /CS31 28 0 R
/CS32 29 0 R /CS33 28 0 R /CS34 29 0 R /CS35 28 0 R /CS36 29 0 R
/CS37 28 0 R /CS4 27 0 R /CS5 26 0 R /CS6 27 0 R /CS7 26 0 R /CS8 27 0 R
/CS9 26 0 R >>
/ExtGState << /GS6 25 0 R >> /Font << /TT24 21 0 R /TT25 17 0 R /TT26 13 0 R /TT27 9 0 R >>
/ProcSet [ /PDF /Text ] >>
/Subtype /Form >>
stream
x??}i?$????K?l2?#?:gu?F??????r$?im?1k???????E???????;?O???=????????????7?????o????oO??????}???O??uz?????z?O????p=M???4n~??w/??;|????OGw>???>???9???cSn'????b????5????????w??\????????_~????t?w8N??9??~?f}??qxy??????o???????M??????'?Or4|?O????|??y??o???=?=
?y?p??1vx?)??7???on????.??w?????-??K??|y:?w}d??????:???>uv??:?.???y???6?nm{????E0\??????n?????B??ra*??x?t?K^???'??7?i?8???]?p?D}??T??-?lcN???_????Q7h??n??s???n==?
??!?
?#~s??F8??G?0?K??e??ul?3n???g??????6?0?a???$??L?j?W??9~U??{?G?U??9fO?????rL?K[Z??E?!????}T|?yr/?}?+?O???6??um????a??E^?K??P??U:??+?pL??N?Q????^\?{a???[??k?N?t/????K{?Ek_???
???t??U#??\O;??????????5??~???????
K??O??9?????</?(?*7????u?n?xa?4??rbd??^N?^z??]?7?T????r?f????|Y?ij?
...