Question

I am currently trying to process a relatively large log file which stores game information in JSON. Any log file averagly ranges from 2000-5000 lines.

Example output (retaining formatting…) from the logfile, note: I have removed the players name, SteamID and Ip Address for his own privacy:

{"timestamp": "2012-09-16 14:10:36", "event": "log_start", "unixTime": 1347768636}
{"timestamp": "2012-09-16 14:10:36", "event": "player_status", "player": {"name": "PLAYER NICKNAME", "userId": 15, "uniqueId": "STEAM_X:X:XXXXXXX (STEAMID)", "team": 1}, "address": "xxx.xxx.xxx.xxx (IP)", "country": "AU"}
{"timestamp": "2012-09-16 14:10:36", "event": "live_on_3", "map": "de_mirage_csgo", "teams": [{"name": "Terrorists", "team": 2}, {"name": "Counter-Terrorists", "team": 3}], "status": 5, "version": "1.0.0 Beta"}

This is where the problem begins. Each line of the log file effectively defines a new JSON object? I am trying to decode all of these objects (storing them as associative arrays) line by line (json_decode($string,TRUE) and from there on I try to merge them into one PHP array through a loop. This does ‘work’ (in the sense there is no visual error), but array_merge doesn’t produce anything near the results I expected. This is my code:

/* parse the logfile into array */
for ($i = 0; $i < $lineCount; $i++) {
    if ($i === 0) { // first iteration
        $arrLog = json_decode($line[$i],true);     
    } else {
        $arrTempLog = json_decode($line[$i],true); // create temp array to store each line
        $arrLog = array_merge($arrLog, $arrTempLog); // merge temp array w/ main array    
    }
} 

Any suggestions or input which would lead me in the right direction to achieving what I need would be greatly appreciated!

Thanks

Answer 1

Please clarify your question if this isn’t what you are looking for.

If you want an array of arrays of that Json data, you can do

$decodedJsonData = array_map(
    function($jsonString) {
        return json_decode($jsonString, true);
    },
    file('/path/to/logfile')
);

This will read the entire file into an array line by line and apply json_decode to each line/element, resulting in an array of arrays of that Json data.

For your Json above, the result would be (demo)

Array
(
    [0] => Array
        (
            [timestamp] => 2012-09-16 14:10:36
            [event] => log_start
            [unixTime] => 1347768636
        )

    [1] => Array
        (
            [timestamp] => 2012-09-16 14:10:36
            [event] => player_status
            [player] => Array
                (
                    [name] => PLAYER NICKNAME
                    [userId] => 15
                    [uniqueId] => STEAM_X:X:XXXXXXX (STEAMID)
                    [team] => 1
                )

            [address] => xxx.xxx.xxx.xxx (IP)
            [country] => AU
        )
    [2] => Array
        (
            [timestamp] => 2012-09-16 14:10:36
            [event] => live_on_3
            [map] => de_mirage_csgo
            [teams] => Array
                (
                    [0] => Array
                        (
                            [name] => Terrorists
                            [team] => 2
                        )

                    [1] => Array
                        (
                            [name] => Counter-Terrorists
                            [team] => 3
                        )

                )
            [status] => 5
            [version] => 1.0.0 Beta
        )
)

Further information:

• file — Reads entire file into an array
• array_map — Applies the callback to the elements of the given arrays
• Chapter on callbacks