How to log pretty printed json in PHP? -

i'm building api in php. api processes json messages third party api.

i want log invalid pretty printed json messages.

so did this:

error_log("test\n" . json_encode($json_string, json_pretty_print)); 

however, when @ logs, json string not pretty printed:

$ tailf error.log 2015-07-13 10:20:03: (mod_fastcgi.c.2701) fastcgi-stderr: test "{\"info\":{\"status\":200,\"msg\":\"ok\"},\"response\":{\"foo\":\"bar\"}" 

i want see like:

$ tailf error.log 2015-07-13 10:20:03: (mod_fastcgi.c.2701) fastcgi-stderr: test {   "info": {      "status": 200,      "msg ": "ok"   },   "response": {      "foo": "bar"   } } 

how can achive result?

error_log("test\n" . json_encode($json_string, json_pretty_print)); 

json_encode() not produce json: produce can read javascript. if give array or object, produce json; if give string, produce javascript string. , that’s you’re doing, that’s you’re getting.

to clear, $json_string string: (as far php concerned, it’s string; if passed same string javascript, interpreted object). pass through json_encode() , you’re going string (a string of doubly-encoded json).

json_pretty_print having no effect here, because you’re not producing json: you’re producing javascript see string.

savvy?

so need (a) turn $json_string php array, , (b) reencode json, time using json_pretty_print flag.

$log_array = json_decode($json_string, true); $json_pretty_string = json_encode($log_array, json_pretty_print); error_log('test' . php_eol . $json_pretty_string); 

rather converting php array , json, better add json_pretty_print flag wherever you’re getting $json_string in first place, if possible.

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alternatively, log $json_string directly (no need encode it: it’s string, can pass error_log() is), , worry prettifying when need read logs. make logs considerably smaller.