Converting Base64 encoded tab delimited file in PHP - php

Question

I am writing a reporting app that needs to consume logs which have been stored in the DB as base 64 encoded strings. I am able to decode them no problem, however, I am having some trouble getting them to be fed into str_getcsv() properly.
Below is the data I am working with, the code and the outputs. It seems to me that once decoded the files are not recognizable as tab-delimited. However, if I decode it with this URL and and save as a text file, I can open it properly in excel.
https://www.base64decode.org/
In PHP however, it seems to be an issue with recognizing some of the tabs and the line breaks seem to completely go away. I think it has to do with the encoding, the DB table and column are both UTF-8. They are being recognized as ASCII - which is a subset of UTF-8, but I am not sure if they need to be explicitly UTF-8 for it to work (the site that works uses UTF-8).
The code: very simple (though at this point I may be going overboard with the encoding)
// get the stored result (laravel eloquent)
$media_result = MediaResult::where("video_id", "=", $media_benchmark->id)->firstOrFail();
# decode the access_log stored as b64 string
$tab_file = base64_decode(mb_convert_encoding($media_result->access_log, "UTF-8"));
$encoding = mb_detect_encoding($tab_file); // I was using iconv() so I grabbed this - it is always ASCII
$new_file = mb_convert_encoding($tab_file,'UTF-8');
$encoding_new = mb_detect_encoding($new_file);
#if I were to echo both encoding variables, it would be ASCII - no matter what I do.
# convert the supposed tab-delimited file into an array
$full_stats = str_getcsv($new_file, 0, "\t");
Here is a sample base64 encoded log:
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
Here is the same string decoded:
URI serverAddress numberOfServerAddressChanges mediaRequestsWWAN transferDuration numberOfBytesTransferred numberOfMediaRequests playbackStartDate playbackSessionID playbackStartOffset playbackType startupTime durationWatched numberOfDroppedVideoFrames numberOfStalls numberOfSegmentsDownloaded segmentsDownloadedDuration downloadOverdue observedBitrateStandardDeviation observedMaxBitrate observedMinBitrate switchBitrate indicatedBitrate observedBitrate http://vevoplaylist-live.hls.adaptive.level3.net/vevo/ch1/01/prog_index.m3u8 8.254.23.254 0 0 0.678280709 1099612 3 2016-05-10 19:21:18 +0000 7A1290DC-1630-49FC-AA64-CC76C181C72A 42 LIVE 0.2532979846000671 16.08326596021652 0 0 3 18 0 -1 25572901.38330787 18207987.3285259 10115548.78381825 492000 21025955.05388924 http://vevoplaylist-live.hls.adaptive.level3.net/vevo/ch1/06/prog_index.m3u8 8.253.32.126 8 0 35.740163622 123481972 43 2016-05-10 19:21:34 +0000 7A1290DC-1630-49FC-AA64-CC76C181C72A 58.028994358 LIVE 0 241.9269759654999 0 0 43 258 0 -1 46885903.03598993 10807457.38240667 -1 4000000 31782360.61452863
Finally, here is the resulting array:
Array ( [0] => URI serverAddress numberOfServerAddressChanges mediaRequestsWWAN transferDuration numberOfBytesTransferred numberOfMediaRequests playbackStartDate playbackSessionID playbackStartOffset playbackType startupTime durationWatched numberOfDroppedVideoFrames numberOfStalls numberOfSegmentsDownloaded segmentsDownloadedDuration downloadOverdue observedBitrateStandardDeviation observedMaxBitrate observedMinBitrate switchBitrate indicatedBitrate observedBitrate http://vevoplaylist-live.hls.adaptive.level3.net/vevo/ch1/ [1] => 1/prog_index.m3u8 8.254.23.254 [2] => 0 [3] => .67828 [4] => 7 [5] => 9 1 [6] => 99612 3 2 [7] => 16- [8] => 5-1 [9] => 19:21:18 + [10] => [11] => [12] => [13] => 7A1290DC-1630-49FC-AA64-CC76C181C72A42 LIVE [14] => .2532979846 [15] => [16] => [17] => 671 16. [18] => 8326596 [19] => 21652 [20] => 03 18 [21] => -1255729 [22] => 1.3833 [23] => 787 182 [24] => 7987.3285259 1 [25] => 115548.78381825 492 [26] => [27] => [28] => 21025955.05388924 http://vevoplaylist-live.hls.adaptive.level3.net/vevo/ch1/06/prog_index.m3u88.253.32.126 8 [29] => 35.740163622123481972 43 2 [30] => 16- [31] => 5-1 [32] => 19:21:34 + [33] => [34] => [35] => [36] => 7A1290DC-1630-49FC-AA64-CC76C181C72A58. [37] => 28994358 LIVE [38] => 241.9269759654999 [39] => 043 258 [40] => -1468859 [41] => 3. [42] => 3598993 1 [43] => 8 [44] => 7457.3824 [45] => 667 -1 4 [46] => [47] => [48] => [49] => [50] => [51] => 31782360.61452863 )

Answer 1

Keep in mind that str_getcsv()
parses only one line of a csv file
expects the delimiter "\t" to be the second parameter, not the third
You probably want something like:
$full_stats = [];
foreach(explode("\n", $decoded) as $line) {
$full_stats[] = str_getcsv($line, "\t");
}
var_dump($full_stats);
This will output an array containing 3 arrays (aka rows) containing 24 items (aka columns) each.
See http://sandbox.onlinephpfunctions.com/code/1ccf5115df6f8c342ff7c7e451f3ea26e081197e for working example and generated output.
Regarding the import of data that contains line breaks you should switch to fget_csv() which handles line breaks correctly:
$csv = <<< eot
"first","my data
with line breaks"
"second", "simple data"
eot;
// We need to "convert" the string to a file handle
$fp = fopen('data://text/plain,' . $csv,'r');
while ($data = fgetcsv($fp)) {
var_dump($data);
}