Forms-3rdparty Migrate Hack -- quick "plugin" to upgrade from CF7-3rdparty to http://wordpress.org/plugins/forms-3rdparty-integration/, or migrate settings across sites.

readme.md

To upgrade deprecated Wordpress Plugin CF7-3rdparty Integration to the new version Forms 3rdparty Integration, or migrate settings between sites.

From discussion at http://wordpress.org/support/topic/how-to-upgrade-from-old-version-to-this-one?replies=1 and more recent request zaus/forms-3rdparty-integration#17.

Your mileage may vary...

0. You should have both plugins enabled with at least one service configured and saved. This is so you have both complete sets of options available for comparison, because you may have to add some extra properties beyond just copy/paste.
1. Upload this to your plugins folder (i.e. install)
2. Go to the Tools admin page, underneath it will be "Forms 3rdparty Migrate"
3. Choose the "mode", which corresponds to the currently selected plugin you want to work with. When reviewing, will show that plugin's settings. When updating, will set that plugin's settings.
4. Choose 'Review' to see the currently selected plugin settings serialized to JSON, and copy them to export. If you are on > PHP 5.4, you'll get prettified output, otherwise...sorry.
5. Choose 'Raw Review' to see the currently selected plugin settings in a 'nicely formatted' array.
6. Choose 'Test' to see what your pasted JSON would like as a nicely formatted array (i.e. like 'Raw Review')
7. Choose 'Update' to set the currently selected plugin from the values in the textarea. Submitted values should be JSON.
8. Select the 'Convert' option if you are migrating between CF7-3rdparty and Forms-3rdparty plugins -- this will perform minor variable renaming for you.
9. Select the 'Merge' option to combine settings with existing. Unselect to overwrite.
10. If "upgrading" from CF7 to Forms, make sure to add any additional properties present in the 'new' format (such as labels) are added, otherwise you might get some PHP warnings when you go back to the Forms-3rdparty admin page. This part might not be necessary if you don't have PHP warnings turned on.
11. Check the integration plugin admin page to make sure your settings are all there.
12. Try the new services.

NOTE Because all of the services are serialized to a single field, there is a limit to how many services you can configure at once.

forms-3rdparty-migrate.php

<?php
/*
Plugin Name: Forms: 3rd-Party Migrate
Plugin URI: https://github.com/zaus/forms-3rdparty-migrate
Description: Export/Import settings for Forms-3rdparty, or migrate to/from CF7-3rdparty
Author: zaus
Version: 0.3.2
Author URI: http://drzaus.com
*/

if(!function_exists('array_replace_recursive')) {
	// ugh...testing on 5.2.17...
	function array_replace_recursive($a, $b) {
		foreach($b as $k => $v) {
			if(is_array($v)) $a[$k] = array_replace_recursive((array)$a[$k], $v);
			else $a[$k] = $v;
		}
		return $a;
	}
}


# upgrade path? http://wordpress.org/support/topic/how-to-upgrade-from-old-version-to-this-one?replies=1
class Forms3rdpartyMigrateHack {

	const pluginPageTitle = 'Forms: 3rd Party Integration Migrate';
	
	const pluginPageShortTitle = 'Forms-3rdparty Migrate';
	
	/**
	 * Admin - role capability to view the options page
	 * @var string
	 */
	const adminOptionsCapability = 'manage_options';


	/**
	 * Self-reference to plugin name
	 * @var string
	 */
	private $N;
	
	/**
	 * Namespace the given key
	 * @param string $key the key to namespace
	 * @return the namespaced key
	 */
	public function N($key = false) {
		// nothing provided, return namespace
		if( ! $key || empty($key) ) { return $this->N; }
		return sprintf('%s_%s', $this->N, $key);
	}



	public function __construct() {
		$this->N = basename(__FILE__, '.php');

		add_action( 'admin_menu', array( &$this, 'admin_init' ), 20 ); // late, so it'll attach menus farther down
	}


	/**
	 * HOOK - Add the "Settings" link to the plugin list entry
	 * @param $links
	 * @param $file
	 */
	function plugin_action_links( $links, $file ) {
		if ( $file != plugin_basename( __FILE__ ) )
			return $links;
	
		$url = $this->plugin_admin_url( array( 'page' => $this->N('config') ) );
	
		$settings_link = '<a title="Capability ' . self::adminOptionsCapability . ' required" href="' . esc_attr( $url ) . '">'
			. esc_html( __( 'Settings', $this->N ) ) . '</a>';
	
		array_unshift( $links, $settings_link );
	
		return $links;
	}


	function admin_init() {
		# perform your code here
		//add_action('admin_menu', array(&$this, 'config_page'));
		
		//add plugin entry settings link
		add_filter( 'plugin_action_links', array(&$this, 'plugin_action_links'), 10, 2 );
		
		//needs a registered page in order for the above link to work?
		#$pageName = add_options_page("Custom Shortcodes - ABT Options", "Shortcodes -ABT", self::adminOptionsCapability, 'abt-shortcodes-config', array(&$this, 'submenu_config'));
		if ( function_exists('add_submenu_page') ){
			
			$page = add_submenu_page('tools.php', __(self::pluginPageTitle), __(self::pluginPageShortTitle), self::adminOptionsCapability, $this->N('config'), array(&$this, 'migrate_form'));
						
			//register options
			add_option( $this->N('settings'), $this->get_default_options() );
		}
		
	} // function

	function get_default_options() {
		return array(
				'mode' => self::NS_Forms3rd,
				'convert' => self::NS_Forms3rd,
				'merge' => 0
			);
	}


	const NS_CF7 = 'Cf73rdPartyIntegration';
	const NS_Forms3rd = 'Forms3rdPartyIntegration';

	const ACTION_GET = 'Get';
	const ACTION_GET_RAW = 'Get Raw';
	const ACTION_TEST = 'Test';
	const ACTION_SET = 'Update';


	function get_input() {

		// check-admin will die; otherwise if 'get' then show default values
		$nopost = empty( $_POST ) || !check_admin_referer( __CLASS__, __CLASS__ );
		
		$options = get_option($this->N('settings'));

		// remember last chosen mode
		if(!$nopost) {
			foreach($this->get_default_options() as $opt => $def) {
				if(isset($_REQUEST[$opt])) $options[$opt] = $_REQUEST[$opt];
			}
			update_option($this->N('settings'), $options);
		}

		// not a get request, "quit"
		if($nopost || !isset($_REQUEST['action'])) $_REQUEST['action'] = false;
		
		switch($_REQUEST['action']) {
			case self::ACTION_TEST:
				// note that update mode "reverses" the from/to input
				$newsetting = stripslashes_deep($_REQUEST['input']);
				$newsetting = json_decode($newsetting, true);

				// are we merging or replacing?
				if(isset($options['merge']) && 1 == $options['merge']) {
					$original = get_option($options['mode'] . '_settings');
					$newsetting = array_replace_recursive($original, $newsetting);
				}

				$options['input'] = print_r($newsetting, true);
				break;
			// just show
			case self::ACTION_GET:
			case self::ACTION_GET_RAW:
			default:
				$asarray = $_REQUEST['action'] == self::ACTION_GET_RAW;

				$setting = get_option($options['mode'] . '_settings');

				$options['input'] = $asarray
						? print_r($setting, true)
						: (defined('JSON_PRETTY_PRINT')
								? json_encode($setting, JSON_PRETTY_PRINT)
								: json_encode($setting)
							);

				break;
			case self::ACTION_SET:
				// note that update mode "reverses" the from/to input
				$setting = stripslashes_deep($_REQUEST['input']);
				// "convert" between plugin variations if necessary
				if(isset($options['convert']) && $options['mode'] != $options['convert']) {
					switch($options['convert']) {
						case self::NS_Forms3rd:
							$from = '"src"';
							$to = '"cf7"';
							break;
						case self::NS_CF7:
							$from = '"cf7"';
							$to = '"src"';
							break;
					}
					if(isset($from)) $setting = str_replace($from, $to, $setting);
				}

				$newsetting = json_decode($setting, true);

				// are we merging or replacing?
				if(isset($options['merge']) && 1 == $options['merge']) {
					$original = get_option($options['mode'] . '_settings');
					$newsetting = array_replace_recursive($original, $newsetting);
				}

				// save the new setting
				update_option($options['mode'] . '_settings', $newsetting);
				
				$options['updated'] = true;
				$options['input'] = $setting;
				break;
		}//--	switch

		return $options;
	}


	function radio_input($key, $name, $field, $input, $type = 'radio') {
		?>
		<div class="field">
			<label for="<?php echo esc_attr($field), '-', esc_attr($key) ?>"><?php _e($name) ?></label>
			<input <?php checked($input[$field], $key) ?> type="<?php echo esc_attr($type) ?>" id="<?php echo esc_attr($field), '-', esc_attr($key) ?>" name="<?php echo esc_attr($field) ?>" value="<?php echo esc_attr($key) ?>" />
		</div>
		<?php
	}

	function radio_input_modes($modes, $field, $input, $type = 'radio') {
		foreach($modes as $key => $name) {
			$this->radio_input($key, $name, $field, $input, $type);
		}
	}

	function show_form($input) {
		?>
		<h2>Migrate Forms-3rdparty</h2>
		<form action="" method="post">
			<?php if(isset($input['updated']) && true == $input['updated']) {
				?>
				<div class="updated">
					<p><?php _e( 'Updated!', $this->N() ); ?></p>
				</div>
				<?php
			}
			?>
			<table class="form-table">
			<tbody>
				<tr>
					<th scope="row"></th>
					<td>
						
					</td>
				</tr>

				<tr>
					<th scope="row">Mode</th>
					<td>
						<?php
						$modes = array(self::NS_CF7 => 'Contact Form 7', self::NS_Forms3rd => 'Forms 3rdparty');
						
						$this->radio_input_modes($modes, 'mode', $input);
						?>
						<p class="description">Which plugin to export/import.  If migrating between plugin versions, make sure to review in one mode, then change modes before updating.</p>
					</td>
				</tr>

				<tr>
					<th scope="row">Convert?</th>
					<td>
						<?php
						$this->radio_input_modes($modes, 'convert', $input);
						?>
						<p class="description">Which plugin we're importing from.  If migrating between plugin versions, this will cause the setting to be reformatted properly.</p>
					</td>
				</tr>

				<tr>
					<th scope="row">Merge?</th>
					<td>
						<?php
						$this->radio_input(1, 'Yes', 'merge', $input, 'checkbox');
						?>
						<p class="description">Should we merge the settings or completely replace?</p>
					</td>
				</tr>

				<tr>
					<th scope="row"><label for="input">Settings</label></th>
					<td>
						<textarea id="input" name="input"><?php echo esc_textarea($input['input']) ?></textarea>
						<p class="description">The current plugin settings, depending on <code>mode</code> chosen.  Serialized as JSON for portability.</p>
					</td>
				</tr>

			</tbody>
			</table>

			<p class="submit">
				<?php
				submit_button(self::ACTION_GET, 'primary', 'action', false, array('id' => 'review', 'title' => 'Get the current settings; copy to export'));
				echo '<span class="spacer"> </span>';
				submit_button(self::ACTION_GET_RAW, 'secondary', 'action', false, array('id' => 'raw', 'title' => 'Get the current settings in raw array format; cannot export'));
				echo '<span class="spacer"> </span>';
				submit_button(self::ACTION_TEST, 'secondary update', 'action', false, array('id' => 'test', 'title' => 'View the entered settings as raw array format; cannot import'));
				echo '<span class="spacer"> </span>';
				submit_button(self::ACTION_SET, 'primary update', 'action', false, array('id' => 'update'));

				wp_nonce_field(__CLASS__, __CLASS__);
				?>
			</p>

		</form>
		<?php
	}

	public function migrate_form() {

		$input = $this->get_input();

		$this->show_form($input);
	}
}//---	class	Forms3rdpartyMigrateHack


new Forms3rdpartyMigrateHack(); // engage