Merge pull request #571 from branupama/json_in_vpd_tool

parse json file for vpd-tool

vpd-tool/include/tool_utils.hpp

@@ -355,5 +355,60 @@ inline types::BinaryVector convertToBinary(const std::string& i_value)
     }
     return l_binaryValue;
 }
+
+/**
+ * @brief API to parse respective JSON.
+ *
+ * @param[in] i_pathToJson - Path to JSON.
+ *
+ * @return Parsed JSON, throws exception in case of error.
+ *
+ * @throw std::runtime_error
+ */
+inline nlohmann::json getParsedJson(const std::string& i_pathToJson)
+{
+    if (i_pathToJson.empty())
+    {
+        throw std::runtime_error("Path to JSON is missing");
+    }
+
+    std::error_code l_ec;
+    if (!std::filesystem::exists(i_pathToJson, l_ec))
+    {
+        std::string l_message{"file system call failed for file: " +
+                              i_pathToJson};
+
+        if (l_ec)
+        {
+            l_message += ", error: " + l_ec.message();
+        }
+        throw std::runtime_error(l_message);
+    }
+
+    if (std::filesystem::is_empty(i_pathToJson, l_ec))
+    {
+        throw std::runtime_error("Empty file: " + i_pathToJson);
+    }
+    else if (l_ec)
+    {
+        throw std::runtime_error("is_empty file system call failed for file: " +
+                                 i_pathToJson + ", error: " + l_ec.message());
+    }
+
+    std::ifstream l_jsonFile(i_pathToJson);
+    if (!l_jsonFile)
+    {
+        throw std::runtime_error("Failed to access Json path: " + i_pathToJson);
+    }
+
+    try
+    {
+        return nlohmann::json::parse(l_jsonFile);
+    }
+    catch (const nlohmann::json::parse_error& l_ex)
+    {
+        throw std::runtime_error("Failed to parse JSON file: " + i_pathToJson);
+    }
+}
 } // namespace utils
 } // namespace vpd

vpd-tool/include/vpd_tool.hpp

@@ -39,6 +39,20 @@ class VpdTool
      */
     nlohmann::json getFruProperties(const std::string& i_fruPath) const;
 
+    /**
+     * @brief An API to get backup-restore config JSON of the system.
+     *
+     * API gets this file by prasing system config JSON file and reading
+     * backupRestoreConfigPath tag.
+     *
+     * @return On success returns valid JSON object, otherwise returns empty
+     * JSON object.
+     *
+     * Note: The caller of this API should verify, is received JSON object is
+     * empty or not.
+     */
+    nlohmann::json getBackupRestoreCfgJsonObj() const noexcept;
+
   public:
     /**
      * @brief Read keyword value.

vpd-tool/meson.build

@@ -13,7 +13,7 @@ sources = ['src/vpd_tool_main.cpp',
 
 vpd_tool_exe = executable('vpd-tool',
                           sources,
-                          include_directories : ['include/'],
+                          include_directories : ['../', 'include/'],
                           dependencies: dependency_list,
                           install: true
                         )

vpd-tool/src/vpd_tool.cpp

@@ -1,3 +1,5 @@
+#include "config.h"
+
 #include "vpd_tool.hpp"
 
 #include "tool_constants.hpp"
@@ -161,4 +163,32 @@ int VpdTool::writeKeyword(std::string i_vpdPath,
     }
     return l_rc;
 }
+
+nlohmann::json VpdTool::getBackupRestoreCfgJsonObj() const noexcept
+{
+    nlohmann::json l_parsedBackupRestoreJson{};
+    try
+    {
+        nlohmann::json l_parsedSystemJson =
+            utils::getParsedJson(INVENTORY_JSON_SYM_LINK);
+
+        // check for mandatory fields at this point itself.
+        if (!l_parsedSystemJson.contains("backupRestoreConfigPath"))
+        {
+            throw std::runtime_error(
+                "backupRestoreConfigPath tag is missing from system config JSON : " +
+                std::string(INVENTORY_JSON_SYM_LINK));
+        }
+
+        l_parsedBackupRestoreJson =
+            utils::getParsedJson(l_parsedSystemJson["backupRestoreConfigPath"]);
+    }
+    catch (const std::exception& l_ex)
+    {
+        // TODO: Enable logging when verbose is enabled.
+        std::cerr << l_ex.what() << std::endl;
+    }
+
+    return l_parsedBackupRestoreJson;
+}
 } // namespace vpd