export "list of propbag parameters" for streams-property-bag (#92)

CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.15)
 cmake_policy(SET CMP0091 NEW) # enable new "MSVC runtime library selection" (https://cmake.org/cmake/help/latest/variable/CMAKE_MSVC_RUNTIME_LIBRARY.html)
 
 project(libCZI 
-      VERSION 0.57.3
+      VERSION 0.58.0
       HOMEPAGE_URL "https://github.com/ZEISS/libczi"
       DESCRIPTION "libCZI is an Open Source Cross-Platform C++ library to read and write CZI")
 

Src/CZICmd/cmdlineoptions.cpp

@@ -1129,7 +1129,7 @@ bool CCmdLineOptions::IsLogLevelEnabled(int level) const
         level = 31;
     }
 
-    return (this->enabledOutputLevels & (1 << level)) ? true : false;;
+    return (this->enabledOutputLevels & (1 << level)) ? true : false;
 }
 
 void CCmdLineOptions::SetOutputFilename(const std::wstring& s)
@@ -2265,25 +2265,8 @@ void CCmdLineOptions::PrintHelpStreamsObjects()
     // Here we parse the JSON-formatted string that contains the property bag for the input stream and
     //  construct a map<int, libCZI::StreamsFactory::Property> from it.
 
-    static constexpr struct
-    {
-        const char* name;
-        int stream_property_id;
-        libCZI::StreamsFactory::Property::Type property_type;
-    }
-    kKeyStringToId[] =
-    {
-        {"CurlHttp_Proxy", libCZI::StreamsFactory::StreamProperties::kCurlHttp_Proxy, libCZI::StreamsFactory::Property::Type::String},
-        {"CurlHttp_UserAgent", libCZI::StreamsFactory::StreamProperties::kCurlHttp_UserAgent, libCZI::StreamsFactory::Property::Type::String},
-        {"CurlHttp_Timeout", libCZI::StreamsFactory::StreamProperties::kCurlHttp_Timeout, libCZI::StreamsFactory::Property::Type::Int32},
-        {"CurlHttp_ConnectTimeout", libCZI::StreamsFactory::StreamProperties::kCurlHttp_ConnectTimeout, libCZI::StreamsFactory::Property::Type::Int32},
-        {"CurlHttp_Xoauth2Bearer", libCZI::StreamsFactory::StreamProperties::kCurlHttp_Xoauth2Bearer, libCZI::StreamsFactory::Property::Type::String},
-        {"CurlHttp_Cookie", libCZI::StreamsFactory::StreamProperties::kCurlHttp_Cookie, libCZI::StreamsFactory::Property::Type::String},
-        {"CurlHttp_SslVerifyPeer", libCZI::StreamsFactory::StreamProperties::kCurlHttp_SslVerifyPeer, libCZI::StreamsFactory::Property::Type::Boolean},
-        {"CurlHttp_SslVerifyHost", libCZI::StreamsFactory::StreamProperties::kCurlHttp_SslVerifyHost, libCZI::StreamsFactory::Property::Type::Boolean},
-        {"CurlHttp_FollowLocation", libCZI::StreamsFactory::StreamProperties::kCurlHttp_FollowLocation, libCZI::StreamsFactory::Property::Type::Boolean},
-        {"CurlHttp_MaxRedirs", libCZI::StreamsFactory::StreamProperties::kCurlHttp_MaxRedirs, libCZI::StreamsFactory::Property::Type::Int32},
-    };
+    int property_info_count;
+    const libCZI::StreamsFactory::StreamPropertyBagPropertyInfo* property_infos = libCZI::StreamsFactory::GetStreamPropertyBagPropertyInfo(&property_info_count);
 
     rapidjson::Document document;
     document.Parse(s.c_str());
@@ -2301,9 +2284,9 @@ void CCmdLineOptions::PrintHelpStreamsObjects()
 
         string name = itr->name.GetString();
         size_t index_of_key = numeric_limits<size_t>::max();
-        for (size_t i = 0; i < sizeof(kKeyStringToId) / sizeof(kKeyStringToId[0]); ++i)
+        for (size_t i = 0; i < static_cast<size_t>(property_info_count); ++i)
         {
-            if (name == kKeyStringToId[i].name)
+            if (name == property_infos[i].property_name)
             {
                 index_of_key = i;
                 break;
@@ -2315,7 +2298,7 @@ void CCmdLineOptions::PrintHelpStreamsObjects()
             return false;
         }
 
-        switch (kKeyStringToId[index_of_key].property_type)
+        switch (property_infos[index_of_key].property_type)
         {
         case libCZI::StreamsFactory::Property::Type::String:
             if (!itr->value.IsString())
@@ -2325,7 +2308,7 @@ void CCmdLineOptions::PrintHelpStreamsObjects()
 
             if (property_bag != nullptr)
             {
-                property_bag->insert(std::make_pair(kKeyStringToId[index_of_key].stream_property_id, libCZI::StreamsFactory::Property(itr->value.GetString())));
+                property_bag->insert(std::make_pair(property_infos[index_of_key].property_id, libCZI::StreamsFactory::Property(itr->value.GetString())));
             }
 
             break;
@@ -2337,7 +2320,7 @@ void CCmdLineOptions::PrintHelpStreamsObjects()
 
             if (property_bag != nullptr)
             {
-                property_bag->insert(std::make_pair(kKeyStringToId[index_of_key].stream_property_id, libCZI::StreamsFactory::Property(itr->value.GetBool())));
+                property_bag->insert(std::make_pair(property_infos[index_of_key].property_id, libCZI::StreamsFactory::Property(itr->value.GetBool())));
             }
 
             break;
@@ -2349,12 +2332,12 @@ void CCmdLineOptions::PrintHelpStreamsObjects()
 
             if (property_bag != nullptr)
             {
-                property_bag->insert(std::make_pair(kKeyStringToId[index_of_key].stream_property_id, libCZI::StreamsFactory::Property(itr->value.GetInt())));
+                property_bag->insert(std::make_pair(property_infos[index_of_key].property_id, libCZI::StreamsFactory::Property(itr->value.GetInt())));
             }
 
             break;
         default:
-            // this actually indicates an internal error - the table kKeyStringToId contains a not yet implemented property type
+            // this actually indicates an internal error - the table property_infos contains a not yet implemented property type
             return false;
         }
     }

Src/libCZI/Doc/version-history.markdown

@@ -15,4 +15,5 @@ version history                 {#version_history}
  0.57.0             | [84](https://github.com/ZEISS/libczi/pull/84)        | add caching for accessors, update CLI11 to version 2.3.2
  0.57.1             | [86](https://github.com/ZEISS/libczi/pull/86)        | small improvement for CMake-build: allow to use an apt-provided CURL-package
  0.57.2             | [90](https://github.com/ZEISS/libczi/pull/90)        | improve thread-safety of CziReader
- 0.57.3             | [91](https://github.com/ZEISS/libczi/pull/91)        | improve error-message
+ 0.57.3             | [91](https://github.com/ZEISS/libczi/pull/91)        | improve error-message
+ 0.58.0             | [92](https://github.com/ZEISS/libczi/pull/92)        | export a list with properties for streams-property-bag

Src/libCZI/StreamsLib/streamsFactory.cpp

@@ -6,6 +6,7 @@
 #include <libCZI_Config.h>
 #include <memory>
 #include <mutex>
+#include <assert.h>
 #include "curlhttpinputstream.h"
 #include "windowsfileinputstream.h"
 #include "simplefileinputstream.h"
@@ -92,6 +93,36 @@ void libCZI::StreamsFactory::Initialize()
                 });
 }
 
+/*static*/const libCZI::StreamsFactory::StreamPropertyBagPropertyInfo* libCZI::StreamsFactory::GetStreamPropertyBagPropertyInfo(int* count)
+{
+    static const StreamsFactory::StreamPropertyBagPropertyInfo kStreamPropertyBagPropertyInfo[] =
+    {
+#if LIBCZI_CURL_BASED_STREAM_AVAILABLE
+        {"CurlHttp_Proxy", StreamsFactory::StreamProperties::kCurlHttp_Proxy, StreamsFactory::Property::Type::String},
+        {"CurlHttp_UserAgent", StreamsFactory::StreamProperties::kCurlHttp_UserAgent, StreamsFactory::Property::Type::String},
+        {"CurlHttp_Timeout", StreamsFactory::StreamProperties::kCurlHttp_Timeout, StreamsFactory::Property::Type::Int32},
+        {"CurlHttp_ConnectTimeout", StreamsFactory::StreamProperties::kCurlHttp_ConnectTimeout, StreamsFactory::Property::Type::Int32},
+        {"CurlHttp_Xoauth2Bearer", StreamsFactory::StreamProperties::kCurlHttp_Xoauth2Bearer, StreamsFactory::Property::Type::String},
+        {"CurlHttp_Cookie", StreamsFactory::StreamProperties::kCurlHttp_Cookie, StreamsFactory::Property::Type::String},
+        {"CurlHttp_SslVerifyPeer", StreamsFactory::StreamProperties::kCurlHttp_SslVerifyPeer, StreamsFactory::Property::Type::Boolean},
+        {"CurlHttp_SslVerifyHost", StreamsFactory::StreamProperties::kCurlHttp_SslVerifyHost, StreamsFactory::Property::Type::Boolean},
+        {"CurlHttp_FollowLocation", StreamsFactory::StreamProperties::kCurlHttp_FollowLocation, StreamsFactory::Property::Type::Boolean},
+        {"CurlHttp_MaxRedirs", StreamsFactory::StreamProperties::kCurlHttp_MaxRedirs, StreamsFactory::Property::Type::Int32},
+        {"CurlHttp_CaInfo", StreamsFactory::StreamProperties::kCurlHttp_CaInfo, StreamsFactory::Property::Type::String},
+        {"CurlHttp_CaInfoBlob", StreamsFactory::StreamProperties::kCurlHttp_CaInfoBlob, StreamsFactory::Property::Type::String},
+#endif
+        {nullptr, 0, StreamsFactory::Property::Type::Invalid},
+    };
+
+    if (count != nullptr)
+    {
+        static_assert(sizeof(kStreamPropertyBagPropertyInfo) / sizeof(kStreamPropertyBagPropertyInfo[0]) > 0, "kStreamPropertyBagPropertyInfo must contain at least one element.");
+        *count = sizeof(kStreamPropertyBagPropertyInfo) / sizeof(kStreamPropertyBagPropertyInfo[0]) - 1;
+    }
+
+    return kStreamPropertyBagPropertyInfo;
+}
+
 bool libCZI::StreamsFactory::GetStreamInfoForClass(int index, StreamClassInfo& stream_info)
 {
     if (index < 0 || index >= GetStreamClassesCount())

Src/libCZI/libCZI_StreamsLib.h

@@ -243,6 +243,24 @@ namespace libCZI
             std::map<int, Property> property_bag; ///< A property-bag with options for creating the stream-object.
         };
 
+        /// Information about a property for the property bag when creating a stream object.
+        struct StreamPropertyBagPropertyInfo
+        {
+            const char* property_name;              ///< (Proposed) name of the property. This is a null-terminated static string. It is enum name with the initial "k" removed.
+            int property_id;                        ///< The numerical identifier for the property.
+            Property::Type property_type;           ///< Type of the property.
+        };
+
+        /// Gets a (static) list of all properties which can be used for the property bag when creating a stream object.
+        /// This list is terminated by an entry with a null property_name. The list is static and will not change during 
+        /// the lifetime of the application, the returned pointer is valid until the application terminates. It is 
+        /// pointing to static memory and must not be freed.
+        ///
+        /// \param [out] count   If non-null, the number of valid elements (not including the terminal element) is put here.
+        ///
+        /// \returns    A pointer to an array containing property-bag information.
+        static const StreamPropertyBagPropertyInfo* GetStreamPropertyBagPropertyInfo(int* count);
+
         /// Perform one-time initialization of the streams objects.
         /// Some stream objects may require some one-time initialization for being operational (this is e.g. the case with
         /// the libcurl-based ones). It is considered good practice to call this function before using any of the other methods.

Src/libCZI_UnitTests/test_streamslib.cpp

@@ -91,3 +91,26 @@ TEST(StreamsLib, TestGetProperty)
         }
     }
 }
+
+TEST(StreamsLib, TestGetStreamPropertyBagPropertyInfo)
+{
+    int property_infos_count = -1;
+    const auto property_infos = StreamsFactory::GetStreamPropertyBagPropertyInfo(&property_infos_count);
+
+    ASSERT_TRUE(property_infos != nullptr);
+    ASSERT_GE(property_infos_count, 0);
+
+    // now, check that the fields 'property_name' and 'property_id' are unique
+    for (int i = 0; i < property_infos_count; ++i)
+    {
+        const auto& info = property_infos[i];
+        for (int j = i + 1; j < property_infos_count; ++j)
+        {
+            const auto& info2 = property_infos[j];
+            EXPECT_FALSE(info.property_name == info2.property_name || info.property_id == info2.property_id);
+        }
+    }
+
+    // check that the list of properties is terminated with an empty entry
+    ASSERT_TRUE(property_infos[property_infos_count].property_name == nullptr);
+}