Added a basic config file, config class, and some stubs

for object storage functionality.

CMakeLists.txt

@@ -1,15 +1,6 @@
 cmake_minimum_required(VERSION 2.8.12)
 project(storagemanager)
 
-option(ENABLE_UNITY_BUILD "" ON)
-option(BUILD_SHARED_LIBS "" OFF)
-option(ENABLE_TESTING "" OFF)
-set(CMAKE_INSTALL_PREFIX_ORIG ${CMAKE_INSTALL_PREFIX})
-set(CMAKE_INSTALL_PREFIX ${CMAKE_CURRENT_BINARY_DIR}/aws-sdk-deps)
-set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${CMAKE_CURRENT_SOURCE_DIR}/aws-sdk-cpp)
-add_subdirectory(aws-sdk-cpp)
-set(CMAKE_INSTALL_PREFIX ${CMAKE_INSTALL_PREFIX_ORIG})
-
 include_directories(include)
 
 set(storagemanager_SRCS 
@@ -29,6 +20,9 @@ set(storagemanager_SRCS
     src/CopyTask.cpp
     src/IOCoordinator.cpp
     src/SessionManager.cpp
+    src/Config.cpp
+    src/CloudStorage.cpp
+    src/S3Storage.cpp
 )
 
 option(TRACE "Enable some tracing output" OFF)
@@ -42,6 +36,16 @@ target_link_libraries(StorageManager boost_system boost_thread boost_filesystem
 add_executable(unit_tests src/unit_tests.cpp ${storagemanager_SRCS})
 target_link_libraries(unit_tests boost_system boost_thread boost_filesystem)
 
+# config & import the AWS SDK
+option(ENABLE_UNITY_BUILD "" ON)
+option(BUILD_SHARED_LIBS "" OFF)
+option(ENABLE_TESTING "" OFF)
+set(CMAKE_INSTALL_PREFIX_ORIG ${CMAKE_INSTALL_PREFIX})
+set(CMAKE_INSTALL_PREFIX ${CMAKE_CURRENT_BINARY_DIR}/aws-sdk-deps)
+set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${CMAKE_CURRENT_SOURCE_DIR}/aws-sdk-cpp)
+add_subdirectory(aws-sdk-cpp)
+set(CMAKE_INSTALL_PREFIX ${CMAKE_INSTALL_PREFIX_ORIG})
+
 #install(TARGETS StorageManager DESTINATION ${ENGINE_BINDIR} COMPONENT platform)
 
 

src/CloudStorage.cpp

@@ -0,0 +1,39 @@
+
+#include "CloudStorage.h"
+#include "Config.h"
+#include "S3Storage.h"
+#include <boost/thread/mutex.hpp>
+#include <syslog.h>
+#include <string>
+
+using namespace std;
+
+namespace
+{
+    boost::mutex m;
+    storagemanager::CloudStorage *inst;
+}
+
+namespace storagemanager
+{
+CloudStorage * CloudStorage::get()
+{
+    if (inst)
+        return inst;
+        
+    Config *conf = Config::get();
+    string type = conf->getValue("ObjectStorage", "service");
+    boost::mutex::scoped_lock s(m);
+    if (inst)
+        return inst;
+    if (type == "s3" || type == "S3")
+        inst = new S3Storage();
+    else {
+        syslog(LOG_CRIT, "CloudStorage: got unknown service provider: %s", type.c_str());
+        return NULL;
+    }
+ 
+    return inst;
+}
+
+}

src/CloudStorage.h

@@ -0,0 +1,24 @@
+
+#ifndef CLOUDSTORAGE_H_
+#define CLOUDSTORAGE_H_
+
+#include <string>
+
+namespace storagemanager
+{
+
+class CloudStorage
+{
+    public:
+        virtual int getObject(const std::string &sourceKey, const std::string &destFile) = 0;
+        virtual int putObject(const std::string &sourceFile, const std::string &destKey) = 0;
+        virtual void deleteObject(const std::string &key) = 0;
+        
+        // this will return a CloudStorage instance of the type specified in StorageManager.cnf
+        static CloudStorage *get();
+    private:
+};
+
+}
+
+#endif

src/Config.cpp

@@ -0,0 +1,70 @@
+
+#include "Config.h"
+#include <boost/thread/mutex.hpp>
+#include <boost/property_tree/ini_parser.hpp>
+#include <boost/filesystem.hpp>
+
+#include <stdlib.h>
+#include <vector>
+
+using namespace std;
+
+namespace
+{
+    boost::mutex m;
+    storagemanager::Config *inst = NULL;
+}
+    
+namespace storagemanager
+{
+
+Config * Config::get()
+{
+    if (inst)
+        return inst;
+    boost::mutex::scoped_lock s(m);
+    if (inst)
+        return inst;
+    inst = new Config();
+    return inst;
+}
+
+Config::Config()
+{
+    /* This will search the current directory,
+       then the $COLUMNSTORE_INSTALL_DIR/etc,
+       then /etc
+       looking for storagemanager.cnf
+       
+       We can change this however we need later.
+    */
+    char *cs_install_dir = getenv("COLUMNSTORE_INSTALL_DIR");
+    
+    vector<string> paths;
+    
+    // the paths to search in order
+    paths.push_back("./");
+    if (cs_install_dir)
+        paths.push_back(cs_install_dir);
+    paths.push_back("/etc");
+    
+    for (int i = 0; i < paths.size(); i++)
+    {
+        if (boost::filesystem::exists(paths[i] + "/storagemanager.cnf"))
+        {
+            filename = paths[i] + "/storagemanager.cnf";
+            break;
+        }
+    }
+    if (filename.empty())
+        throw runtime_error("Config: Could not find the config file for StorageManager");
+        
+    boost::property_tree::ini_parser::read_ini(filename, contents);
+}
+
+string Config::getValue(const string &section, const string &key) const
+{
+    return contents.get<string>(section + "." + key);
+}
+
+}

src/Config.h

@@ -0,0 +1,27 @@
+
+#ifndef CONFIG_H_
+#define CONFIG_H_
+
+#include <boost/property_tree/ptree.hpp>
+#include <string>
+
+
+namespace storagemanager
+{
+class Config : public boost::noncopyable
+{
+    public:
+        static Config *get();
+        
+        std::string getValue(const std::string &section, const std::string &key) const;
+        
+    private:
+        Config();
+        
+        std::string filename;
+        boost::property_tree::ptree contents;
+};
+
+}
+
+#endif

src/S3Storage.cpp

@@ -0,0 +1,31 @@
+
+#include "S3Storage.h"
+
+using namespace std;
+
+namespace storagemanager
+{
+
+S3Storage::S3Storage()
+{
+}
+
+S3Storage::~S3Storage()
+{
+}
+
+int S3Storage::getObject(const string &courceKey, const string &destFile)
+{
+    return 0;
+}
+
+int S3Storage::putObject(const string &sourceFile, const string &destKey)
+{
+    return 0;
+}
+
+void S3Storage::deleteObject(const string &key)
+{
+}
+
+}

src/S3Storage.h

@@ -0,0 +1,30 @@
+
+#ifndef S3STORAGE_H_
+#define S3STORAGE_H_
+
+#include <string>
+#include "CloudStorage.h"
+
+namespace storagemanager
+{
+
+class S3Storage : public CloudStorage
+{
+    public:
+        S3Storage();
+        virtual ~S3Storage();
+
+        int getObject(const std::string &sourceKey, const std::string &destFile);
+        int putObject(const std::string &sourceFile, const std::string &destKey);
+        void deleteObject(const std::string &key);
+
+    private:
+        
+};
+
+
+
+
+}
+
+#endif

storagemanager.cnf

@@ -0,0 +1,10 @@
+[ObjectStorage]
+service=S3
+
+[S3]
+region = us-west-1
+
+# S3 credentials will come through standard AWS methods
+# ex, by setting AWS_ACCESS_KEY_ID & AWS_SECRET_ACCESS_KEY envvars.
+# see https://docs.aws.amazon.com/cli/latest/userguide/cli-chap-configure.html
+