Use std::optional if available.

Currently, SDK requires C++11 minimum.
So, boost::optional type is used for optional values.
For C++17 and above more convenient is to use std::optional instead.
This PR makes the optional type used configurable.

Relates-To: NLAM-23
Signed-off-by: sopov <ext-alexander.sopov@here.com>

Author: asopov-here

CONTRIBUTING.md

@@ -257,12 +257,13 @@ inline PublishDataRequest& WithLayerId(std::string&& layer_id) {
 
 #### API optional parameters
 
-The SDK uses `boost::optional` for optional members, parameters, or return types. Also, function comments should indicate whether the parameter is optional or required.
+The SDK uses `olp::porting::optional` mapped to either `boost::optional` or `std::optional` for optional members,
+parameters, or return types. Also, function comments should indicate whether the parameter is optional or required.
 
 Example:
 
 ```cpp
-inline const boost::optional<std::string>& GetBillingTag() const {
+inline const olp::porting::optional<std::string>& GetBillingTag() const {
   return billing_tag_;
 }
 

docs/dataservice-cache-example.md

@@ -89,7 +89,7 @@ You can get data from a [versioned layer](https://www.here.com/docs/bundle/data-
    olp::dataservice::read::VersionedLayerClient layer_client (
                        client::HRN catalog,
                        std::string layer_id,
-                       boost::optional<int64_t> catalog_version,
+                       olp::porting::optional<int64_t> catalog_version,
                        client::OlpClientSettings settings);
    ```
 
@@ -102,7 +102,7 @@ You can get data from a [versioned layer](https://www.here.com/docs/bundle/data-
    ```cpp
    auto request = olp::dataservice::read::DataRequest()
                     .WithPartitionId(first_partition_id)
-                    .WithBillingTag(boost::none)
+                    .WithBillingTag(olp::porting::none)
                     .WithFetchOption(olp::dataservice::read::FetchOptions::OnlineIfNotFound);
    ```
 

docs/dataservice-read-catalog-example.md

@@ -359,7 +359,7 @@ You can request any data version from a [versioned layer](https://www.here.com/d
    olp::dataservice::read::VersionedLayerClient layer_client (
                        client::HRN catalog,
                        std::string layer_id,
-                       boost::optional<int64_t> catalog_version,
+                       olp::porting::optional<int64_t> catalog_version,
                        client::OlpClientSettings settings);
    ```
 

examples/ProtectedCacheExample.cpp

@@ -108,13 +108,13 @@ int RunExampleReadWithCache(const AccessKey& access_key,
 
   // Create appropriate layer client with HRN, layer name and settings.
   olp::dataservice::read::VersionedLayerClient layer_client(
-      olp::client::HRN(catalog), first_layer_id, boost::none, client_settings);
+      olp::client::HRN(catalog), first_layer_id, olp::porting::none, client_settings);
 
   // Retrieve the partition data
   // Create a DataRequest with appropriate LayerId and PartitionId
   auto request = olp::dataservice::read::DataRequest()
                    .WithPartitionId(first_partition_id)
-                   .WithBillingTag(boost::none);
+                   .WithBillingTag(olp::porting::none);
   if (cache_settings.disk_path_protected.is_initialized()) {
     request.WithFetchOption(olp::dataservice::read::FetchOptions::CacheOnly);
   }
@@ -145,6 +145,6 @@ int RunExampleProtectedCache(const AccessKey& access_key, const std::string& cat
   }
   // Read data with protected cache. Set mutable cache to none.
   cache_settings.disk_path_protected = cache_settings.disk_path_mutable;
-  cache_settings.disk_path_mutable = boost::none;
+  cache_settings.disk_path_mutable = olp::porting::none;
   return RunExampleReadWithCache(access_key, cache_settings, catalog);
 }

examples/ReadExample.cpp

@@ -119,7 +119,7 @@ bool HandleDataResponse(
 }  // namespace
 
 int RunExampleRead(const AccessKey& access_key, const std::string& catalog,
-                   const boost::optional<int64_t>& catalog_version) {
+                   const olp::porting::optional<int64_t>& catalog_version) {
   // Create a task scheduler instance
   std::shared_ptr<olp::thread::TaskScheduler> task_scheduler =
       olp::client::OlpClientSettingsFactory::CreateDefaultTaskScheduler(1u);
@@ -162,7 +162,7 @@ int RunExampleRead(const AccessKey& access_key, const std::string& catalog,
 
     // Create CatalogRequest
     auto request =
-        olp::dataservice::read::CatalogRequest().WithBillingTag(boost::none);
+        olp::dataservice::read::CatalogRequest().WithBillingTag(olp::porting::none);
 
     // Run the CatalogRequest
     auto future = catalog_client.GetCatalog(request);
@@ -185,7 +185,7 @@ int RunExampleRead(const AccessKey& access_key, const std::string& catalog,
     // Retrieve the partitions metadata
     // Create a PartitionsRequest with appropriate LayerId
     auto request =
-        olp::dataservice::read::PartitionsRequest().WithBillingTag(boost::none);
+        olp::dataservice::read::PartitionsRequest().WithBillingTag(olp::porting::none);
 
     // Run the PartitionsRequest
     auto future = layer_client.GetPartitions(request);
@@ -206,7 +206,7 @@ int RunExampleRead(const AccessKey& access_key, const std::string& catalog,
     // Create a DataRequest with appropriate LayerId and PartitionId
     auto request = olp::dataservice::read::DataRequest()
                        .WithPartitionId(first_partition_id)
-                       .WithBillingTag(boost::none);
+                       .WithBillingTag(olp::porting::none);
 
     // Run the DataRequest
     auto future = layer_client.GetData(request);

examples/ReadExample.h

@@ -21,7 +21,7 @@
 
 #include "Examples.h"
 
-#include <boost/optional.hpp>
+#include <olp/core/porting/optional.hpp>
 
 /**
  * @brief Dataservice read example. Authenticate client using access key id and
@@ -35,4 +35,4 @@
  */
 int RunExampleRead(
     const AccessKey& access_key, const std::string& catalog,
-    const boost::optional<int64_t>& catalog_version = boost::none);
+    const olp::porting::optional<int64_t>& catalog_version = olp::porting::none);

examples/main.cpp

@@ -68,7 +68,7 @@ int RequiredArgumentError(const tools::Option& arg) {
 }
 int ParseArguments(const int argc, char** argv, AccessKey& access_key,
                    std::string& catalog,
-                   boost::optional<int64_t>& catalog_version,
+                   olp::porting::optional<int64_t>& catalog_version,
                    std::string& layer_id,
                    olp::dataservice::read::SubscribeRequest::SubscriptionMode&
                        subscription_mode) {
@@ -128,7 +128,7 @@ int ParseArguments(const int argc, char** argv, AccessKey& access_key,
       if (ss.fail() || !ss.eof()) {
         std::cout << "invalid catalog version value -- '" << *it
                   << "', but int64 is expected." << std::endl;
-        catalog_version = boost::none;
+        catalog_version = olp::porting::none;
       }
     } else if (IsMatch(*it, tools::kLayerIdOption)) {
       if (++it == arguments.end()) {
@@ -168,7 +168,7 @@ int ParseArguments(const int argc, char** argv, AccessKey& access_key,
 
 int RunExamples(const AccessKey& access_key, int examples_to_run,
                 const std::string& catalog,
-                const boost::optional<int64_t>& catalog_version,
+                const olp::porting::optional<int64_t>& catalog_version,
                 const std::string& layer_id,
                 olp::dataservice::read::SubscribeRequest::SubscriptionMode
                     subscription_mode) {
@@ -213,7 +213,7 @@ int main(int argc, char** argv) {
   std::string catalog;     // the HRN of the catalog to which you to publish data
   std::string layer_id;    // the of the layer inside the catalog to which you
                            // want to publish data
-  boost::optional<int64_t> catalog_version;  // version of the catalog.
+  olp::porting::optional<int64_t> catalog_version;  // version of the catalog.
   auto subscription_mode =
       olp::dataservice::read::SubscribeRequest::SubscriptionMode::
           kSerial;  // subscription mode for read stream layer example

external/CMakeLists.txt

@@ -97,7 +97,7 @@ if(OLP_SDK_ENABLE_DEFAULT_CACHE_LMDB)
     endif()
 endif()
 
-find_package(Boost QUIET)
+find_package(Boost 1.82.0 QUIET)
 if(NOT TARGET Boost AND NOT Boost_FOUND)
     add_subdirectory(boost)
     set(BOOST_ROOT ${EXTERNAL_BOOST_ROOT} PARENT_SCOPE)

olp-cpp-sdk-authentication/include/olp/authentication/AuthenticationClient.h

@@ -36,7 +36,7 @@
 #include <olp/authentication/Types.h>
 #include <olp/core/client/ApiResponse.h>
 #include <olp/core/client/CancellationToken.h>
-#include <boost/optional.hpp>
+#include <olp/core/porting/optional.hpp>
 
 /**
  * @brief Rules all the other namespaces.
@@ -65,15 +65,15 @@ class AUTHENTICATION_API AuthenticationClient {
     /**
      * @brief (Optional) The scope assigned to the access token.
      */
-    boost::optional<std::string> scope{boost::none};
+    olp::porting::optional<std::string> scope{olp::porting::none};
 
     /**
      * @brief (Optional) The device ID assigned to the access token.
      *
      * @note This field is only necessary if you want to apply a oauth rate
      * limit on a particular device.
      */
-    boost::optional<std::string> device_id{boost::none};
+    olp::porting::optional<std::string> device_id{olp::porting::none};
 
     /**
      * @brief (Optional) The number of seconds left before the access
@@ -89,7 +89,7 @@ class AUTHENTICATION_API AuthenticationClient {
      * requires it. Fully overrides default body and resets the request content
      * type.
      */
-    boost::optional<std::string> custom_body{boost::none};
+    olp::porting::optional<std::string> custom_body{olp::porting::none};
   };
 
   /**

olp-cpp-sdk-authentication/include/olp/authentication/AuthenticationCredentials.h

@@ -21,7 +21,7 @@
 
 #include <string>
 
-#include <boost/optional/optional.hpp>
+#include <olp/core/porting/optional.hpp>
 #include "AuthenticationApi.h"
 
 namespace olp {
@@ -58,7 +58,7 @@ class AUTHENTICATION_API AuthenticationCredentials {
    * @return An optional value with your credentials if the credentials were
    * read successfully, or no value in case of failure.
    */
-  static boost::optional<AuthenticationCredentials> ReadFromStream(
+  static olp::porting::optional<AuthenticationCredentials> ReadFromStream(
       std::istream& stream);
 
   /**
@@ -81,7 +81,7 @@ class AUTHENTICATION_API AuthenticationCredentials {
    * @return The optional value with your credentials if the credentials were
    * read successfully, or no value in case of failure.
    */
-  static boost::optional<AuthenticationCredentials> ReadFromFile(
+  static olp::porting::optional<AuthenticationCredentials> ReadFromFile(
       std::string filename = {});
   AuthenticationCredentials() = delete;