Create biergarten brewery pipeline project (#199)

pipeline/src/web_client/curl_web_client_get.cc

@@ -0,0 +1,86 @@
+/**
+ * @file web_client/curl_web_client_get.cc
+ * @brief CURLWebClient::Get() implementation.
+ */
+
+#include "web_client/curl_web_client.h"
+
+#include <cstdint>
+#include <limits>
+#include <memory>
+#include <stdexcept>
+#include <string>
+
+#include <curl/curl.h>
+
+using CurlHandle = std::unique_ptr<CURL, decltype(&curl_easy_cleanup)>;
+
+static constexpr long kConnectionTimeout = 10;
+static constexpr long kRequestTimeout = 30;
+static constexpr int32_t kOkHttpStatus = 200;
+
+static CurlHandle CreateHandle() {
+  CURL* handle = curl_easy_init();
+  if (handle == nullptr) {
+    throw std::runtime_error(
+        "[CURLWebClient] Failed to initialize libcurl handle");
+  }
+  return {handle, &curl_easy_cleanup};
+}
+
+static void SetCommonGetOptions(CURL* curl, const std::string& url) {
+  curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
+  curl_easy_setopt(curl, CURLOPT_USERAGENT, "biergarten-pipeline/0.1.0");
+  curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
+  curl_easy_setopt(curl, CURLOPT_MAXREDIRS, 5L);
+  curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, kConnectionTimeout);
+  curl_easy_setopt(curl, CURLOPT_TIMEOUT, kRequestTimeout);
+  curl_easy_setopt(curl, CURLOPT_ACCEPT_ENCODING, "gzip");
+}
+
+// curl write callback that appends response data into a std::string
+static size_t WriteCallbackString(void* contents, const size_t size,
+                                  const size_t nmemb, void* userp) {
+  const size_t real_size = size * nmemb;
+  auto* str = static_cast<std::string*>(userp);
+  str->append(static_cast<char*>(contents), real_size);
+  return real_size;
+}
+
+std::string CURLWebClient::Get(const std::string& url) {
+  const CurlHandle curl = CreateHandle();
+
+  std::string response_string;
+
+  SetCommonGetOptions(curl.get(), url);
+
+  curl_easy_setopt(curl.get(), CURLOPT_WRITEFUNCTION, WriteCallbackString);
+  curl_easy_setopt(curl.get(), CURLOPT_WRITEDATA, &response_string);
+
+  CURLcode curl_result = curl_easy_perform(curl.get());
+
+  if (curl_result != CURLE_OK) {
+    const auto error = std::string("[CURLWebClient] GET failed: ") +
+                       curl_easy_strerror(curl_result);
+    throw std::runtime_error(error);
+  }
+
+  long curl_http_code = 0;
+  curl_easy_getinfo(curl.get(), CURLINFO_RESPONSE_CODE, &curl_http_code);
+
+  if (curl_http_code < std::numeric_limits<int32_t>::min() ||
+      curl_http_code > std::numeric_limits<int32_t>::max()) {
+    throw std::runtime_error("[CURLWebClient] Invalid HTTP status code: " +
+                             std::to_string(curl_http_code));
+  }
+
+  const int32_t http_code = static_cast<int32_t>(curl_http_code);
+
+  if (http_code != kOkHttpStatus) {
+    const std::string error = "[CURLWebClient] HTTP error " +
+                              std::to_string(http_code) + " for URL " + url;
+    throw std::runtime_error(error);
+  }
+
+  return response_string;
+}