AyeCode / invoicing

		$prepared_item = new stdClass();

		// Post ID.

		if ( isset( $request['id'] ) ) {

			$existing_item = $this->get_post( $request['id'] );

			if ( is_wp_error( $existing_item ) ) {

				return $existing_item;

			}

			$prepared_item->ID 		  = $existing_item->ID;

		}

		$schema = $this->get_item_schema();

		$prepared_invoice = new stdClass();

		// Post ID.

		if ( isset( $request['id'] ) ) {

			$existing_invoice = $this->get_post( $request['id'] );

			if ( is_wp_error( $existing_invoice ) ) {

				return $existing_invoice;

			}

			$prepared_invoice->ID 		  = $existing_invoice->ID;

			$prepared_invoice->invoice_id = $existing_invoice->ID;

		}

		$schema = $this->get_item_schema();