Example of extending the REST API in Sugar 7. This example overrides the OOTB Reports export functionality to enable CSV exports. To use this, drop the file in the custom/Reports/clients/base/api/ directory.

ReportsExportCsvApi.php

<?php
if(!defined('sugarEntry') || !sugarEntry) die('Not A Valid Entry Point');
/*
 * Copyright (c) 2013, John Mertic
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 * * Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 * 
 * * Redistributions in binary form must reproduce the above copyright notice, this
 *   list of conditions and the following disclaimer in the documentation and/or
 *   other materials provided with the distribution.
 * 
 * * Neither the name of the SugarCRM nor the names of its
 *   contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

require_once('data/BeanFactory.php');
require_once('include/download_file.php');
require_once('modules/Reports/ReportCache.php');
require_once('modules/Reports/Report.php');
require_once('modules/Reports/templates/templates_export.php');

class ReportsExportCsvApi extends SugarApi
{
	// how long the cache is ok, in minutes
    private $cacheLength = 10;

    public function registerApiRest() {
        return array(
            'exportRecord' => array(
                'reqType' => 'GET',
                'path' => array('Reports', '?', 'csv'),
                'pathVars' => array('module', 'record', 'export_type'),
                'method' => 'exportCsv',
                'rawReply'=> true,
                'shortHelp' => 'This method exports a record as a CSV file',
                'longHelp' => '',
            ),
        );
    }

	/**
     * Export a Report As CSV
     * @param ServiceBase $api
     * @param array $args Arguments array built by the service base
     * @return null
     */
    public function exportCsv(ServiceBase $api, array $args)
    {
    	$this->requireArgs($args,array('record'));
        $args['module'] = 'Reports';

        $GLOBALS['disable_date_format'] = FALSE;

        $saved_report = $this->loadBean($api, $args, 'view');

        if(!$saved_report->ACLAccess('view')) {
            throw new SugarApiExceptionNotAuthorized('No access to view records for module: Reports');
        }

        global $beanList, $beanFiles;
        global $sugar_config,$current_language;
        
        $report_filename = false;
        if($saved_report->id != null)
        {
            //Translate pdf to correct language
            $reporter = new Report(html_entity_decode($saved_report->content), '', '');
            if ( $reporter->report_def['report_type'] != 'tabular' ) {
                throw new SugarApiException('CSV export only valid for Rows and Columns reports');
                return;
            }

            $reporter->layout_manager->setAttribute("no_sort",1);
            $reporter->fromApi = true;
            //Translate csv to correct language
            $_REQUEST['module'] = $reporter->report_def['module'];
            $mod_strings = return_module_language($current_language);

            //Generate actual csv file, return back as raw content
            return template_handle_export($reporter, false);
        }
    }
}

I used this, and the response was the following:

stdClass Object
(
[team_count] =>
[team_name] => Array
(
[0] => stdClass Object
(
[id] => 1
[name] => Global
[name_2] =>
[primary] => 1
)

    )

[id] => b802e797-0fc3-c37a-75c1-523cc73cc9a8
[name] => Call List By Last Date Contacted
[module] => Contacts
[report_type] => tabular
[content] => {"display_columns":[{"name":"date_modified","label":"Last Modified","table_key":"self"},{"name":"full_name","label":"Contact Name","table_key":"self"},{"name":"phone_work","label":"Office Phone","table_key":"self"},{"name":"name","label":"Account Name","table_key":"Contacts:accounts"},{"name":"full_name","label":"Assigned to","table_key":"Contacts:assigned_user_link"}],"module":"Contacts","group_defs":[],"summary_columns":[],"report_name":"Call List By Last Date Contacted","chart_type":"none","numerical_chart_column":"","numerical_chart_column_type":"","assigned_user_id":"1","report_type":"tabular","full_table_list":{"self":{"value":"Contacts","module":"Contacts","label":"Contacts","children":{"accounts":"accounts","reports_to_link":"reports_to_link","team_link":"team_link","created_by_link":"created_by_link","modified_user_link":"modified_user_link","assigned_user_link":"assigned_user_link"},"dependents":[]},"Contacts:accounts":{"label":"Account","link_def":{"relationship_name":"accounts_contacts","name":"accounts","link_type":"many","label":"Account","table_key":"Contacts:accounts","bean_is_lhs":0},"parent":"self","optional":0,"module":"Accounts","name":"Contacts  \u003E  Account","dependents":["display_cols_row_4"]},"Contacts:assigned_user_link":{"label":"Assigned to User","link_def":{"relationship_name":"contacts_assigned_user","name":"assigned_user_link","link_type":"one","label":"Assigned to User","table_key":"Contacts:assigned_user_link","bean_is_lhs":0},"parent":"self","optional":true,"module":"Users","name":"Contacts  \u003E  Assigned to User","dependents":["display_cols_row_6"]}},"filters_def":{"Filter_1":{"operator":"AND","0":{"name":"do_not_call","table_key":"self","qualifier_name":"equals","input_name0":["no"]}}}}
[deleted] => 
[date_entered] => 2013-09-20T15:10:00-07:00
[date_modified] => 2013-09-25T17:22:00-07:00
[assigned_user_id] => 1
[modified_user_id] => 1
[assigned_user_name] => Jen Smith
[created_by] => 1
[is_published] => 
[last_run_date] => 
[chart_type] => none
[schedule_type] => pro
[favorite] => 
[my_favorite] => 
[_acl] => stdClass Object
    (
        [fields] => stdClass Object
            (
            )

    )

[following] => 
[_module] => Reports

)

Question:

• Is this the correct response, or did I implement this correctly?
• What part of this array has the actual CSV content?

Thanks,

Emilio