RuddWire » json

Perl script make MySQL query, binds variables, outputs JSON

Colin — Sat, 17 Jul 2010 00:40:11 +0000

An example of a Perl script that is called by an ajax request. The script takes in just one parameter, opens a MySQL DB connection, binds the parameter to the query, and sends the query. The result is then formatted into JSON and returned to the browser.

This can be seen in action on this page: http://www.ruddwire.com/friendly-data/naics-explorer/, in the NAICS search box.

 
#!/usr/bin/perl
 
use strict;
use DBI();
use CGI qw(:standard);
 
 
my $dbh;
my $sth;
my $mySQL;
my $result = '({"failure":1})';
 
#QUERY PARAMS
my $q;
 
 
 
my $ref;
my $table = "";
my $tableRow;
 
my $query = new CGI;
 
 
 
 
 
if($query->param()){
 
 
    $q = $query->param('q');
    $q =~ s/\s+/%/;  # REPLACE SPACES WITH WILD CARD CHARACTER, CAUSES TO SEARCH FOR ALL WORDS, NOT JUST PHRASE
 
    ### Connect to the database.
	my $dbh = DBI->connect("DBI:mysql:database=***DBNAME***;host=localhost",
                         "***USERNAME***", "***PASSWORD***",
                         {'RaiseError' => 1});
 
    	### GET INDUSTRY NAME AND CODE
    	$mySQL = "SELECT code,industry FROM naics2007IndustryIndex WHERE industry LIKE ? ORDER BY industry";
 
 
     $sth = $dbh->prepare($mySQL);
     $sth->execute("%".${q}."%");
 
      while ($ref = $sth->fetchrow_hashref()) {
 
		  while ((my $key, my $value) = each(%$ref)){
		  	  $value =~ s/"/\\"/g;
			  $tableRow .= "\"${value}\",";
		  }
 
		  $tableRow =~ s/,$//;
		  $tableRow = "[${tableRow}],";
 
		  $table .= $tableRow;
		  $tableRow = "";
      }
 
		$table =~ s/,$//;
 
	  	$result = '{"failure":0,"result":['.$table.']}';         
 
}### END IF QUERY
 
 
 
print "Content-type: text/javascript; charset=iso-8859-1\n\n";
 
print $result;
 
exit(0);

Perl script makes MySQL query; outputs to JSON

Colin — Mon, 21 Jun 2010 01:37:34 +0000

An example of a Perl script that is called by an ajax request. The script takes in a few parameters, opens a MySQL DB connection, and then makes a rather tortuous query. The result is then formatted into JSON and returned to the browser.

This can be seen in action on this page: http://www.ruddwire.com/friendly-data/naics-explorer/.

#!/usr/bin/perl
 
use strict;
use DBI();
use CGI qw(:standard);
 
 
my $dbh;
my $sth;
my $mySQL;
my $result = '({"failure":1})';
 
#QUERY PARAMS
my $strLn;
my $classification;
my $getDef;
my $getIndus;
 
my $naicsMatch = "";
my $countMatch = "";
my @subClasses;
my $ref;
my $table = "";
my $tableRow;
 
 
sub scrubInputText {
 
   my($it) = @_;
   my $shellChars = q-[&;`'\\\"\|\*\?\~<>\^\(\)\[\]\{\}\$\\n\\r]-;    #`
 
    $it =~ s/$shellChars//g;
    $it =~ s/^\s+|\s+$//g;
 
   return $it;
 
}
 
 
my $query = new CGI;
 
if($query->param()){
 
    $strLn = &scrubInputText($query->param('strLn'));
    $classification = &scrubInputText($query->param('cls'));
    $getDef = &scrubInputText($query->param('getDef'));
    $getIndus = &scrubInputText($query->param('getIndus'));
 
    ###HANDLE GROUPED SECTOR CODES, IE: 31-33
    if($classification =~ /-/){
    	@subClasses = split("-",$classification);
		$naicsMatch = "AND (";
 
		for(my $subClass = $subClasses[0]; $subClass <= $subClasses[1]; $subClass++){
    		$naicsMatch .= "code LIKE '${subClass}%' OR ";
    		$countMatch .= "code LIKE '${subClass}%' OR ";
    	}
    	$countMatch =~ s/ OR $//;
    	$naicsMatch =~ s/ OR $//;
    	$naicsMatch .= ")";
    }else{
       $naicsMatch = "AND code LIKE '${classification}%'";
    }
 
	if($strLn != 2){$countMatch = "code LIKE Concat(naics2007.code,'%')";}
 
    ### Connect to the database.
	my $dbh = DBI->connect("DBI:mysql:database=***DBNAME***;host=localhost",
                         "***USERNAME***", "***PASSWORD***",
                         {'RaiseError' => 1});
 
    if($getDef){
    	$mySQL = "SELECT definition FROM naics2007definitions WHERE code='${classification}'";
    }elsif($getIndus){
    	### GET FINAL INDUSTRY NAME
    	$mySQL = "SELECT code,industry FROM naics2007IndustryIndex WHERE code LIKE '${classification}' ORDER BY industry";
    }else{
    	### GET INDUSTRY CLASSIFICATIONS
 
 
 		$mySQL = "SELECT code,title, ".
     	"(SELECT COUNT(code) FROM naics2007IndustryIndex WHERE ".
     	"CASE naics2007.code ".
     	"WHEN '31-33' THEN (code LIKE '31%' OR code LIKE '32%' OR code LIKE '33%') ".
     	"WHEN '44-45' THEN (code LIKE '44%' OR code LIKE '45%') ".
     	"WHEN '48-49' THEN (code LIKE '48%' OR code LIKE '49%') ".
     	"ELSE code LIKE Concat(naics2007.code,'%') END) AS c".
     	" FROM naics2007 WHERE (CHAR_LENGTH(code) = $strLn OR code LIKE '__-__')".$naicsMatch;
 
    }
 
 
     $sth = $dbh->prepare($mySQL);
     $sth->execute();
 
      while ($ref = $sth->fetchrow_hashref()) {
 
		  while ((my $key, my $value) = each(%$ref)){
		  	  $value =~ s/"/\\"/g;
			  $tableRow .= "\"${value}\",";
		  }
 
		  $tableRow =~ s/,$//;
		  $tableRow = "[${tableRow}],";
 
		  $table .= $tableRow;
		  $tableRow = "";
      }
 
		$table =~ s/,$//;
 
	  	$result = '{"failure":0,"result":['.$table.']}';
 
}### END IF QUERY
 
 
 
print "Content-type: application/json; charset=iso-8859-1\n\n";
 
print $result;
 
exit(0);

jQuery parsererror: clean up your JSON objects

Colin — Mon, 08 Mar 2010 03:49:23 +0000

Has your JSON using jQuery web app suddenly stopped working? Getting a parsererror on your JSON objects, where you got none before? This is what happened to me when my site upgraded to jQuery 1.4.

I use the Google API’s jQuery, and it automatically upgraded my whole site to jQuery 1.4. In jQuery 1.4, they decided to tighten up the JSON parsing engine, so that it is now unforgiving of any lax standards. You have to follow the JSON standard spelled out here — to the letter. In my case, that meant changing any single quoted values or names to double quotes, and getting rid of opening and closing parentheses. Like most fixes, it was an easy fix, once I figured it out. Hope this helps.

-Colin