feat: add rest transport client

src/Transport/RestTransportClient.php

@@ -0,0 +1,91 @@
+<?php
+/**
+ * REST package transport client.
+ *
+ * @package WPContentSync
+ */
+
+namespace WPContentSync\Transport;
+
+use WPContentSync\Package\ContentPackage;
+
+final class RestTransportClient {
+	public function testConnection( string $base_url, string $username, string $application_password ): bool {
+		$response = wp_remote_get(
+			$this->endpoint( $base_url, 'status' ),
+			$this->requestArgs( $username, $application_password )
+		);
+
+		$this->assertSuccessfulResponse( $response, 200 );
+
+		return true;
+	}
+
+	public function sendPackage( string $base_url, string $username, string $application_password, ContentPackage $package ): bool {
+		$body = wp_json_encode( array( 'package' => $package->toArray() ) );
+
+		if ( false === $body ) {
+			throw RestTransportException::remoteRejected( 'Unable to encode REST package payload.' );
+		}
+
+		$args                            = $this->requestArgs( $username, $application_password );
+		$args['body']                    = $body;
+		$args['headers']['Content-Type'] = 'application/json';
+
+		$response = wp_remote_post( $this->endpoint( $base_url, 'package' ), $args );
+
+		$this->assertSuccessfulResponse( $response, 200 );
+
+		return true;
+	}
+
+	private function endpoint( string $base_url, string $route ): string {
+		return rtrim( $base_url, '/' ) . '/wp-json/wp-content-sync/v1/' . ltrim( $route, '/' );
+	}
+
+	/**
+	 * @return array<string, mixed>
+	 */
+	private function requestArgs( string $username, string $application_password ): array {
+		return array(
+			'timeout' => 15,
+			'headers' => array(
+				// phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_encode -- Basic auth requires base64-encoded username:application-password credentials.
+				'Authorization' => 'Basic ' . base64_encode( $username . ':' . $application_password ),
+			),
+		);
+	}
+
+	/**
+	 * @param mixed $response HTTP response.
+	 */
+	private function assertSuccessfulResponse( $response, int $expected_code ): void {
+		if ( is_wp_error( $response ) ) {
+			throw RestTransportException::connectionFailed( $response->get_error_message() );
+		}
+
+		$status_code = wp_remote_retrieve_response_code( $response );
+
+		if ( 401 === $status_code || 403 === $status_code ) {
+			throw RestTransportException::authenticationFailed( 'REST authentication failed.' );
+		}
+
+		if ( $expected_code !== $status_code ) {
+			throw RestTransportException::remoteRejected( $this->responseMessage( $response ) );
+		}
+	}
+
+	/**
+	 * @param array<string, mixed> $response HTTP response.
+	 */
+	private function responseMessage( array $response ): string {
+		$body    = wp_remote_retrieve_body( $response );
+		$decoded = json_decode( $body, true );
+
+		if ( is_array( $decoded ) && isset( $decoded['message'] ) && is_string( $decoded['message'] ) ) {
+			return $decoded['message'];
+		}
+
+		return 'REST transport request failed.';
+	}
+}