Lisantra Technologies, Llc

php Code Sample

    
<?php
/**
 * I get all blog entries from the database for a single blog
 *
 * @author Michael Gatto <mgatto@lisantra.com>
 * @param resource $dbh is a PDO connection handler
 * @return mixed $blog['select_all'] is the base variable for this fuse
 * @return mixed $blog['select_all']['error'] holds data from a PDO exception
 */

try {

    /**
     * INPUTS
     */
    // base variable name abstracted the name for easy refactoring
    $params['circuit'] = "blog";
    // = $myFusebox->orginalCircuit

    //type of query abstracted for easy refactoring
    $params['type'] = "select_all";
    // = $myFusebox->thisFuseaction

    //build the array acting as a namespace: $blog['select_all']
    ${$params['circuit']}[$params['type']] = array();

    //we could also cast to string with "" around the variable,
    //but let's be explicit aboutour casting
    $params['blog_id'] = (string) $attributes['blogid']; //should be a UUID


    /**
     * PROCESSING
     */
    //we could use MySQL's date functions to format 'written_on',
    // but let's keep that in the view
    ${$params['circuit']}[$params['type']]['sql'] = "
        SELECT
            e.id,
            e.entry_id,
            e.blog_id,
            e.entry_title,
            e.written_on,
            e.created_by_id,
            a.author_name
        FROM entries e
        INNER JOIN authors a
            ON a.author_id = e.written_by
        WHERE e.blog_id = :blog_id";

    //prepared statements are more verbose, but secure and sometimes
    // more efficient on db resources: YMMV.
    ${$params['circuit']}[$params['type']]['stmt'] =
        $dbh->prepare( ${$params['name']."['sql']"} );

    //make sure a param type is specified, matching the cast in the input section
    ${$params['circuit']}[$params['type']]['stmt']->bindParam(
        ":blog_id", $params['blog_id'], PDO::PARAM_STR
        );

    //execute without assigning it to a variable to maintain explicitness
    ${$params['circuit']}[$params['type']]['stmt']->execute();

    //let's get the variable to use in the view as an associative array so we
    //can use count and foreach nicely. Objects would work, too.
    ${$params['circuit']}[$params['type']]['rs'] =
        ${$params['circuit']}[$params['type']]['stmt']->fetchAll( PDO::FETCH_ASSOC );

    //let's get a count and provide it as a convenience to the view or other
    //models, or an exception
    if ( ${$params['circuit']}[$params['type']]['rs'] ) {
        //PDO does not have a count function, so count the elements in
        //the rs array instead
        ${$params['circuit']}[$params['type']]['count'] =
            count( ${$params['circuit']}[$params['type']]['rs'] );
    }
    else {
        //maybe I shouldn't use an exception for an error case?
        throw new Exception(
            "No records were returned because: " .
            ${$params['circuit']}[$params['type']]['stmt']->errorInfo()
        );
        }


    /**
     * CLEAN UP
     * prevent variable pollution. Ah, Php 5.3 namespaces will be great here.
     * NOTE: unsetting $params does NOT destroy the dynamic variables!
     */
    unset( $params );

    //post-process $blog output array is needed
    //for example, we could run htmlspecialchars() for good security practice
    array_map( htmlspecialchars, ${$params['circuit']}[$params['type']]['rs'] );

    }
    //differentiate between the different exception types
    catch (PDOException $e)  {
        ${$params['circuit']}[$params['type']]['error'][]['type'] =
            "PDO::" . $e->getCode();
        ${$params['circuit']}[$params['type']]['error'][]['details'] =
            $e->getMessage() .
            " in file: " . $e->getFile() .
            " on line: " . $e->getLine();
            //do not print 'details' to the screen, since it can expose
            //database structure to users!
    }
    //catch any non-PDO exceptions
    catch (Exception $e) {
        ${$params['circuit']}[$params['type']]['error'][]['type'] =
            "Application::" . $e->getCode();
        ${$params['circuit']}[$params['type']]['error'][]['details'] =
            $e->getMessage() .
            " in file: " . $e->getFile() .
            " on line: " . $e->getLine();
    }
?>