Re: Extra Data in POST response

On Mon, 2023-02-13 at 04:13 +0000, Ashley Sheridan wrote: > On 13/02/2023 03:35, John Iliffe wrote: > > On Sun, 2023-02-12 at 22:41 +0000, Ashley Sheridan wrote: > > > On 12/02/2023 22:29, John Iliffe wrote: > > > > On Sun, 2023-02-12 at 21:15 +0000, Ashley Sheridan wrote: > > > > > On 12/02/2023 19:49, John Iliffe wrote: > > > > > > I seem to be getting extraneous data in the response sent to the > > > > > > browser by PHP. > > > > > > > > > > > > The server query is an AJAX request in json format which is received > > > > > > and > > > > > > processed correctly and the result is sent using the "echo" > > > > > > function. I have > > > > > > checked and the area where the response is constructed is empty when > > > > > > processing > > > > > > starts. > > > > > > > > > > > > The data received by the browser has BOTH the request json data > > > > > > followed by the > > > > > > correct response in the received string (result not HTML, just a > > > > > > string that > > > > > > will eventually be converted to json but so far will only be caught in > > > > > > the > > > > > > browser for display). > > > > > > > > > > > > I'm using XMLHttpObject in the browser and I haven't been > > > > > > able to find a way to > > > > > > separate the request from the response. Before I construct an elegant > > > > > > workaround does POST normally return the request? If not, what am I > > > > > > doing > > > > > > wrong? So far I have always used GET so I know it doesn't return > > > > > > the request. > > > > > > > > > > > > For completeness, here is what the server says it is sending to the > > > > > > browser > > > > > > (using echo) (The json may be wrong; I'm still just trying to > > > > > > receive it). > > > > > > > > > > > > ------ > > > > > > sent to browser: > > > > > > > > > > > > "jres":[{"item_id":"5","i_type":"OL","i_name":"Student > > > > > > Success > > > > > > > > > > > > Pages","i_stock":"99924","i_price":"14.00","i_books_box":"0"},{"item_id":"13","i > > > > > > _type":"CD","i_name":"Basic Instructors > > > > > > Guide 9th > > > > > > > > > > > > Ed.","i_stock":"9983","i_price":"19.95","i_books_box":"0"},{"item_id":"20","i_ty > > > > > > pe":"SG","i_name":"Canadian Amateur > > > > > > Radio Basic Qualification Study > > > > > > > > > > > > Guide","i_stock":"274","i_price":"44.95","i_books_box":"20"},{"item_id":"21","i_ > > > > > > type":"SG","i_name":"Canadian Amateur > > > > > > Radio Advanced Qualification Study > > > > > > > > > > > > Guide","i_stock":"1586","i_price":"49.95","i_books_box":"16"}] > > > > > > ----- > > > > > > > > > > > > here is the original request from the browser, as decoded by server > > > > > > ------ > > > > > > request method: POST > > > > > > requests: array ( > > > > > > 'req' => > > > > > > '{"func":"act","item":"438"}', > > > > > > ) > > > > > > > > > > > > json last error message: No error > > > > > > decoded_args: > > > > > > func=act > > > > > > item=438 > > > > > > > > > > > > ------- > > > > > > > > > > > > and here is what the browser says it received back: > > > > > > > > > > > > ----- > > > > > > received:-->array(2) { > > > > > > ["func"]=> > > > > > > string(3) "act" > > > > > > ["item"]=> > > > > > > string(3) "438" > > > > > > } > > > > > > > > > > > > > > > > > > "jres":[{"item_id":"5","i_type":"OL","i_name":"Student > > > > > > Success > > > > > > > > > > > > Pages","i_stock":"99924","i_price":"14.00","i_books_box":"0"},{"item_id":"13","i > > > > > > _type":"CD","i_name":"Basic Instructors > > > > > > Guide 9th > > > > > > > > > > > > Ed.","i_stock":"9983","i_price":"19.95","i_books_box":"0"},{"item_id":"20","i_ty > > > > > > pe":"SG","i_name":"Canadian Amateur > > > > > > Radio Basic Qualification Study > > > > > > > > > > > > Guide","i_stock":"274","i_price":"44.95","i_books_box":"20"},{"item_id":"21","i_ > > > > > > type":"SG","i_name":"Canadian Amateur > > > > > > Radio Advanced Qualification Study > > > > > > > > > > > > Guide","i_stock":"1586","i_price":"49.95","i_books_box":"16"}]<-- > > > > > > ----- > > > > > > > > > > > > Thanks in advance for any suggestions you can give. > > > > > > > > > > > > John > > > > > > ====== > > > > > Hi John, > > > > > > > > > > What does your PHP code look like? Something in it must be outputting > > > > > the request, as that's not something that would just occur all by > > > > > itself. > > > > > > > > > > Regards, > > > > > Ash > > > > Thanks for the quick response Ash. That's what I have been asking myself > > > > and I > > > > wondered if returning the query is a requirement of the POST protocol. Without > > > > sending the entire script, I can say that there are only two "echo" > > > > statements > > > > in it (by doing a grep for echo) and they are mutually exclusive: > > > > > > > > ----- > > > > [John@prod04 test]$ grep -n echo ./XXXXXXb.php > > > > 140: echo $json_resp; > > > > 145: echo "<br />XXXXXb: Either func or item was not set<br > > > > />err is true, > > > > errno=" . $errno . "<br />"; > > > > ----- > > > > <?php > > > > ob_start(); > > > > /* XXXXXXb responds to AJAX inventory report requests > > > > * from updated XXXXXXXX. > > > > * > > > > * Written J Iliffe 2/2023 > > > > * copyright John Iliffe, 2023, all rights reserved. > > > > */ > > > > //header('Content-Type: application/json; charset=utf-8'); > > > > header('Content-Type: text/plain; charset=utf-8'); > > > > $func = ""; > > > > $item = 0; > > > > $err = false; > > > > $errno = 0; > > > > > > > > $fx = fopen("/tmp/XXXXXb.txt","w"); > > > > > > > > fwrite($fx,("\nrequest method: " . > > > > $_SERVER['REQUEST_METHOD'])); > > > > fwrite($fx,("\nrequests: " . var_export($_REQUEST,true))); > > > > > > > > /* get the json request block as associative array */ > > > > if (isset($_POST['req'])) > > > > { > > > > $decoded_args = > > > > json_decode($_POST['req'],true,5,JSON_INVALID_UTF8_IGNORE); > > > > > > > > if ((isset($decoded_args['func'])) && > > > > (isset($decoded_args['item']))) > > > > { > > > > $func = $decoded_args['func']; > > > > $item = $decoded_args['item']; > > > > fwrite($fx,("\nfunc and item isset as " . $func . > > > > " and " . $item . > > > > "\n")); > > > > } > > > > else > > > > { > > > > $err = true; > > > > $errno = 2; > > > > } > > > > > > > > fwrite($fx,("\njson last error message: " . > > > > json_last_error_msg() . > > > > "\n")); > > > > fwrite($fx,("decoded_args:" . var_dump($decoded_args) . > > > > "\n")); > > > > fwrite($fx,("func=" . $decoded_args['func'] . > > > > "\n")); > > > > fwrite($fx,("item=" . $decoded_args['item'] . > > > > "\n")); > > > > } > > > > else > > > > { > > > > $err = true; > > > > $errno = 1; > > > > } > > > > > > > > /* if we are good to go here, open database, create query */ > > > > $json_resp = '"jres":['; //json opening > > > > > > > > ----I deleted the database activity from here--- > > > > > > > > if (! $err) > > > > { > > > > if (! $res) > > > > { > > > > $err=true; > > > > $errno = 4; > > > > } > > > > else > > > > { > > > > for ($i=0;$i<$rows;$i++) > > > > { > > > > $r_arr = pg_fetch_array($res,null,PGSQL_ASSOC); > > > > > > > > $json_rec=json_encode($r_arr,0,16); > > > > > > > > if ($json_rec === false) > > > > { > > > > fwrite ($fx,("\nrecord at " . $i . " bad, > > > > " . > > > > json_last_error_msg() . "\n")); > > > > } > > > > > > > > > > > > if (($i < $rows) && ($i != 0)) // no opening or > > > > trailing ',' > > > > { > > > > $json_resp .= ','; > > > > } > > > > > > > > $json_resp .= $json_rec; > > > > } > > > > > > > > $json_resp .= ']'; > > > > > > > > fwrite($fx,("\njson sent to browser:\n -->" . $json_resp . > > > > "<---\n\n\n")); > > > > } > > > > } > > > > } > > > > > > > > if (! $err) > > > > { > > > > echo $json_resp; > > > > ob_flush(); > > > > } > > > > else > > > > { > > > > echo "<br />adm9005b: Either func or item was not set<br > > > > />err is true, > > > > errno=" . $errno . "<br />"; > > > > ob_flush(); > > > > } > > > > > > > > exit; > > > > ?> > > > > ------ > > > > > > > > This is pretty much what I have so far and why it has been driving me nuts for > > > > several days now...the query is never repeated anywhere in the echoed output. > > > > What actually comes back to the browser, as you can see above, is is the result > > > > generated by this; prepended with PHP's analysis of the original POST > > > > query. > > > > > > > > Thanks for taking the time to look. > > > > > > > > John > > > > ====== > > > It might be some error output, which is being supressed by the > > > ob_start(), and then output when you do the ob_flush(). Why are you > > > using those, as it's unusual for what you appear to be doing here. > > > > > > Thanks, > > > Ash > > > > > Thanks for the suggestion Ash. I commented out the ob_start and ob_flush > > statements but the problem persists. > > > > I was using buffering because I have to send headers as part of the response, at > > the very least the content-type header when I convert the response to json. The > > reason it is a simple string at the moment is that I didn't want my inexperience > > with json to get involved with getting the communications working properly. > > > > Regards, > > > > John > > ====== > > Have you tried attaching a debugger, to see at what point the extra > output is being shown? Is it being added to the response variable > somewhere, possibly from the code that you removed from your excerpt? > > Also, you don't need to use object buffers if you're sending headers. > Typically, you'd use output buffering if you wanted to prevent something > from making it to the final output, or if you needed to control the > output during a streamed response. > > Thanks, > Ash ======= Thank you Ash. As it turned out, the note from Janis has the answer, var_dump outputs rather than returning a value so it was doing a sort of a phantom "echo" in the background. Sorry to have wasted your time. Also, thanks very much for the comments of the output buffering. I read somewhere that if it was necessary to send headers then I have to buffer the output to avoid having any html sent before the headers and I, mistakenly, assumed that I would have to do that here, even though no html is being sent. Works properly without buffering so I will delete that. That, I suppose, is the result of learning while doing! (I'm the only one here that works on the server, and I'm also the sysadmin, operator, and network guy) Regards, and thanks, John ======