Re^3: json return value

It's really not that difficult...

Server

use v5.14;
use CGI ();
use JSON::PP ();

my $q     = 'CGI'->new;
my $json  = 'JSON::PP'->new;
my $input = $json->decode( $q->param('POSTDATA') );

my $a = $input->{a};
my $b = $input->{b};
my $c = $a + $b;

print $q->header("application/json");
print $json->encode({ c => $c });
[download]

Client

use v5.14;
use HTTP::Tiny ();
use JSON::PP ();

my $json = 'JSON::PP'->new;
my $http = 'HTTP::Tiny'->new;
my $url  = 'http://buzzword.org.uk/2013/json-addition.cgi';

my $input    = { a => 40, b => 2 };
my @request  = ($url => { content => $json->encode($input) });
my $response = $http->post(@request);
my $output   = $json->decode($response->{content});
say $output->{c};
[download]

(All modules used above are part of Perl core as of 5.14+, but CGI is scheduled to leave core in a future version of Perl.)

package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name

Comment on Re^3: json return value Select or Download Code

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Re^4: json return value by stenasc (Novice) on Jul 14, 2013 at 22:27 UTC
Thank you very much. I greatly appreciate it. I get the correct value returned when I use the URL http://buzzword.org.uk/2013/json-addition.cgi but I get malformed JSON string, neither array, object, number, string or atom, at er offset 0 (before "<!DOCTYPE HTML PUBLI...") at json_client.pl line 12 when I use my own URL http://myurl.com/cgi-bin/json_mode.cgi. I have installed the server in the cgi-bin directory with permission 755 and the perl has valid syntax etc. It looks as if I cannot access the cgi file in the cgi-bin directory. Do you know a way around this? I also see it described as text/cgi whereas some, but not all of the other cgi files are described as application/cgi. Any ideas why this is the case?	[reply]
Re^5: json return value by tobyink (Canon) on Jul 15, 2013 at 05:45 UTC
Have you visited http://myurl.com/cgi-bin/json_mode.cgi in your browser? `package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name`	[reply]
Re^6: json return value by stenasc (Novice) on Jul 15, 2013 at 07:42 UTC
Yes...I get the following. It looks as if I don't have permission to contact the website. Internal Server Error The server encountered an internal error or misconfiguration and was unable to complete your request. Please contact the server administrator, webmaster@myurl.com and inform them of the time the error occurred, and anything you might have done that may have caused the error. More information about this error may be available in the server error log. Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.	[reply]
Re^7: json return value by Corion (Patriarch) on Jul 15, 2013 at 07:44 UTC
Re^6: json return value by stenasc (Novice) on Jul 15, 2013 at 20:44 UTC
Yes...it gives me this.. Internal Server Error The server encountered an internal error or misconfiguration and was unable to complete your request. Please contact the server administrator, webmaster@myurl.com and inform them of the time the error occurred, and anything you might have done that may have caused the error. More information about this error may be available in the server error log. Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request. However if I have a small cgi like the following, it works fine when accessed through the browser `#!/usr/bin/perl print "Content-type:text/html\r\n\r\n"; print '<html>'; print '<head>'; print '<title>Hello Word</title>'; print '</head>'; print '<body>'; print '<h2>Hello World</h2>'; print '</body>'; print '</html>';` [download] I've been in contact with the server administrator and he sent me the log file results. Mon Jul 15 14:49:20 2013 error client 87.194.165.154 Premature end of script headers: json_mode.cgi He also suggested that I add the following to the code, but that is already in the code He also told me that it was because the script wasn't outputting valid html headers. print("Content-type: text/json"); or print("Content-type:application/json"); The client is working fine because I can get the correct response from http://buzzword.org.uk/2013/json-addition.cgi'	[reply] [d/l]
Re^7: json return value by poj (Abbot) on Jul 16, 2013 at 07:27 UTC
Re^8: json return value by stenasc (Novice) on Jul 16, 2013 at 07:50 UTC
Some notes below your chosen depth have not been shown here
Re^7: json return value by Anonymous Monk on Jul 16, 2013 at 08:23 UTC
Re^5: json return value by Anonymous Monk on Jul 14, 2013 at 23:44 UTC
Do you know a way around this? Yes, work through these checklists, when you find a problem on the list, use a solution from the list, when you find a problem not on the list (rare), post the error message and problem description here brian's Guide to Solving Any Perl Problem, CGI Help Guide , Troubleshooting Perl CGI scripts I also see it described as text/cgi whereas some, but not all of the other cgi files are described as application/cgi. Any ideas why this is the case? If your program is running as cgi (say under mod_cgi) then its responsible for that header, otherwise the webserver sent that header. However, chances are your cgi-bin isn't setup properly, cause `text/cgi and application/cgi` are rare (plain text files are text/plain). So examine your server configuration and compare to https://httpd.apache.org/docs/2.2/howto/public_html.html#cgi / Apache Tutorial: Dynamic Content with CGI	[reply] [d/l]