add new http module

tooling/pipeline/includes/web_client/http_web_client.h

@@ -0,0 +1,49 @@
+/**
+* @file web_client/http_web_client.h
+* @brief cpp-httplib implementation of the WebClient interface.
+*/
+
+#ifndef BIERGARTEN_PIPELINE_INCLUDES_HTTP_WEB_CLIENT_CURL_WEB_CLIENT_H_
+#define BIERGARTEN_PIPELINE_INCLUDES_HTTP_WEB_CLIENT_CURL_WEB_CLIENT_H_
+
+
+#include "web_client/web_client.h"
+
+#include <string>
+
+/**
+ * @brief WebClient implementation backed by cpp-httplib.
+ *
+ * Supports HTTP and HTTPS (requires
+ * OpenSSL; see HTTPLIB_USE_OPENSSL_IF_AVAILABLE in CMakeLists.txt).
+ *
+ * URL parsing splits a full URL into scheme + host and path + query so that
+ * httplib::Client can be constructed correctly. A new client instance is
+ * created per request; th  is is intentional given the low call volume in the
+ * pipeline (Wikipedia enrichment, near-100 % cache hits).
+ */
+class HttpWebClient final : public WebClient {
+public:
+  HttpWebClient() = default;
+  ~HttpWebClient() override = default;
+
+  /**
+   * @brief Executes a blocking HTTP/HTTPS GET request against a full URL.
+   *
+   * @param url Fully-qualified URL, e.g. "https://en.wikipedia.org/api/rest_v1/page/summary/Berlin"
+   * @return Response body on HTTP 2xx; throws std::runtime_error otherwise.
+   */
+  std::string Get(const std::string& url) override;
+
+  /**
+   * @brief Percent-encodes a single URI component (query parameter value or
+   *        path segment). Delegates to httplib::encode_uri_component().
+   *
+   * @param value Raw string to encode.
+   * @return Percent-encoded string safe for use in a URL.
+   */
+  std::string UrlEncode(const std::string& value) override;
+};
+
+
+#endif