Add DataStorm demos

Author: pepone

.gitignore

@@ -4,6 +4,8 @@ server
 locator
 publisher
 subscriber
+reader
+writer
 talk
 chatserver
 chatgl2client
@@ -17,6 +19,8 @@ chatpollclient
 !**/msbuild/locator
 !**/msbuild/publisher
 !**/msbuild/subscriber
+!**/msbuild/reader
+!**/msbuild/writer
 
 !**/Sources/client
 !**/Sources/server

cpp/DataStorm/README.md

@@ -0,0 +1,93 @@
+# C++ Demos
+
+- [Overview](#overview)
+- [Building and Running the Demos on Linux and macOS](#building-and-running-the-demos-on-linux-and-macos)
+- [Building and Running the Demos on Windows](#building-and-running-the-demos-on-windows)
+
+## Overview
+
+This directory contains C++ sample programs for DataStorm. These examples are
+provided to get you started on using a particular DataStorm feature or coding
+technique.
+
+## Building and Running the Demos on Linux and macOS
+
+### Prerequisites
+
+The makefiles require GNU make 3.80 or later.
+
+On macOS, the command-line demos require the Xcode Command Line Tools to be
+installed (use `xcode-select --install` to install them).
+
+If you've installed DataStorm in a non-standard location or want to use the
+source tree build, you'll need to set the `DATASTORM_HOME` environment variable
+with the path name of the installation directory or source tree:
+```
+export DATASTORM_HOME=~/testing/datastorm
+```
+
+### Building the Demos
+
+Review the settings in `make/Make.rules`. For example, set `OPTIMIZE=yes`
+to build with optimization.
+
+When you're ready to start the build, run `make`, for example:
+```
+make V=1
+```
+
+`V=1` in the example above turns on verbose output.
+
+The `clean` and `distclean` targets allow you clean all the demos. `clean`
+removes the binary files created by the build; `distclean` removes all these
+files plus the C++ files generated by slice2cpp.
+
+Note that `make clean` only removes the binary files for the configuration and
+platform specified with the `CONFIGS` and `PLATFORMS` variables in `Make.rules`.
+
+You can also build or clean a single demo with `make <demo-path>[_clean|_distclean]`,
+for example:
+```
+make V=1 stock
+make stock_distclean
+```
+
+### Running the Demos
+
+Refer to the README.md file in each demo directory for usage instructions.
+
+## Building and Running the Demos on Windows
+
+### Building the Demos
+
+Open the solution file `DataStorm C++ demos.sln` to build the sample programs.
+
+The demos are configured to use the DataStorm NuGet package provided by ZeroC.
+The build downloads automatically this DataStorm NuGet package.
+
+If you have disabled the automatic download of NuGet packages by Visual Studio,
+you need to restore the packages before you build using `Tools > NuGet Package
+Manager > Manage NuGet Packages for Solution...` in Visual Studio.
+
+Then select your target configuration (Debug or Release) and platform (Win32
+or x64). Right click on the desired demo in the Solution Explorer window and
+select `Build`.
+
+### Running the Demos
+
+You need to add the DataStorm and Ice `bin` directories to your PATH before running
+the demos.
+
+If you are building Debug, add the Debug `bin` directories with a command similar
+to:
+```
+set PATH=%USERPROFILE%\datastorm\demos\cpp\packages\zeroc.datastorm.v143.1.1.1\build\native\bin\x64\Debug;%USERPROFILE%\datastorm\demos\cpp\packages\zeroc.ice.v143.3.7.9\build\native\bin\x64\Debug;%PATH%
+```
+
+If you are building Release, add the Release `bin` directories with a command
+similar to:
+```
+set PATH=%USERPROFILE%\datastorm\demos\cpp\packages\zeroc.datastorm.v143.1.1.1\build\native\bin\x64\Release;%USERPROFILE%\datastorm\demos\cpp\packages\zeroc.ice.v143.3.7.9\build\native\bin\x64\Release;%PATH%
+```
+
+Then refer to the README.md file in each demo directory for usage instructions.

cpp/DataStorm/clock/Makefile.mk

@@ -0,0 +1,5 @@
+# Copyright (c) ZeroC, Inc. All rights reserved.
+
+$(demo)_dependencies    = DataStorm Ice
+
+demos += $(demo)

cpp/DataStorm/clock/README.md

@@ -0,0 +1,15 @@
+This demo illustrates how to implement a custom encoder and decoder for the
+topic value type `chrono::system_clock::time_point`.
+
+To run the demo, start the writer and specify the name of a city:
+```
+writer
+```
+
+In a separate window, start the reader:
+```
+reader
+```
+
+The reader will print the time sent by the writer. You can start multiple
+writers and readers.

cpp/DataStorm/clock/Reader.cpp

@@ -0,0 +1,86 @@
+//
+// Copyright (c) ZeroC, Inc. All rights reserved.
+//
+
+#include <DataStorm/DataStorm.h>
+#include <Ice/Ice.h>
+
+#include <chrono>
+#include <iostream>
+
+using namespace std;
+
+namespace DataStorm
+{
+    template<> struct Encoder<chrono::system_clock::time_point>
+    {
+        static Ice::ByteSeq encode(const chrono::system_clock::time_point&)
+        {
+            assert(false); // Not used by the reader but it still needs to be declared.
+            return Ice::ByteSeq{};
+        }
+    };
+
+    template<> struct Decoder<chrono::system_clock::time_point>
+    {
+        static chrono::system_clock::time_point decode(const Ice::ByteSeq& data)
+        {
+            // Decode the number of seconds since epoch. The value is encoded in a way which doesn't depend on the
+            // platform endianess (little endian with variable number of bytes).
+            long long int value = 0;
+            for (auto p = data.rbegin(); p != data.rend(); ++p)
+            {
+                value = value * 256 + static_cast<long long int>(*p);
+            }
+            return chrono::time_point<chrono::system_clock>(chrono::seconds(value));
+        }
+    };
+};
+
+int
+main(int argc, char* argv[])
+{
+    try
+    {
+        // CtrlCHandler must be called before the node is created or any other threads are started.
+        Ice::CtrlCHandler ctrlCHandler;
+
+        // Instantiates node.
+        DataStorm::Node node(argc, argv, "config.reader");
+
+        // Shutdown the node on Ctrl-C.
+        ctrlCHandler.setCallback([&node](int) { node.shutdown(); });
+
+        // Instantiates the "time" topic.
+        DataStorm::Topic<string, chrono::system_clock::time_point> topic(node, "time");
+
+        // Instantiate a reader to read the time from all the topic cities.
+        auto reader = DataStorm::makeAnyKeyReader(topic);
+
+        // Wait for at least on writer to connect.
+        reader.waitForWriters();
+
+        // Prints out the received samples.
+        reader.onSamples(
+            nullptr,
+            [](const DataStorm::Sample<string, chrono::system_clock::time_point>& sample)
+            {
+                auto time = chrono::system_clock::to_time_t(sample.getValue());
+                char timeString[100];
+                if (strftime(timeString, sizeof(timeString), "%x %X", localtime(&time)) == 0)
+                {
+                    timeString[0] = '\0';
+                }
+                cout << "received time for `" << sample.getKey() << "': " << timeString << endl;
+            });
+
+        // Exit once the user hits Ctrl-C to shutdown the node.
+        node.waitForShutdown();
+    }
+    catch (const std::exception& ex)
+    {
+        cerr << ex.what() << endl;
+        return 1;
+    }
+    return 0;
+}

cpp/DataStorm/clock/Writer.cpp

@@ -0,0 +1,78 @@
+// Copyright (c) ZeroC, Inc. All rights reserved.
+
+#include <DataStorm/DataStorm.h>
+#include <Ice/Ice.h>
+
+#include <iostream>
+#include <string>
+#include <thread>
+
+using namespace std;
+
+namespace DataStorm
+{
+    template<> struct Encoder<chrono::system_clock::time_point>
+    {
+        static Ice::ByteSeq encode(const chrono::system_clock::time_point& time)
+        {
+            // Encode the number of seconds since epoch. The value is encoded in a way which doesn't depend on the
+            // platform endianess (little endian with variable number of bytes).
+            Ice::ByteSeq data;
+            auto value = chrono::time_point_cast<chrono::seconds>(time).time_since_epoch().count();
+            while (value)
+            {
+                data.push_back(static_cast<std::byte>(value % 256));
+                value = value / 256;
+            }
+            return data;
+        }
+    };
+
+    template<> struct Decoder<chrono::system_clock::time_point>
+    {
+        static chrono::system_clock::time_point decode(const Ice::ByteSeq&)
+        {
+            assert(false); // Not used by the reader but it still needs to be declared.
+            return chrono::system_clock::time_point();
+        }
+    };
+};
+
+int
+main(int argc, char* argv[])
+{
+    try
+    {
+        // CtrlCHandler must be called before the node is created or any other threads are started.
+        Ice::CtrlCHandler ctrlCHandler;
+
+        // Instantiates node.
+        DataStorm::Node node(argc, argv, "config.writer");
+
+        // Shutdown the node on Ctrl-C.
+        ctrlCHandler.setCallback([&node](int) { node.shutdown(); });
+
+        // Asks for city name to publish updates
+        string city;
+        cout << "Please enter city name: ";
+        getline(cin, city);
+
+        // Instantiates the "time" topic.
+        DataStorm::Topic<string, chrono::system_clock::time_point> topic(node, "time");
+
+        // Instantiate a writer to write the time from the given city.
+        auto writer = DataStorm::makeSingleKeyWriter(topic, city);
+
+        while (!node.isShutdown())
+        {
+            writer.update(chrono::system_clock::now());
+            this_thread::sleep_for(chrono::seconds(1));
+        }
+    }
+    catch (const std::exception& ex)
+    {
+        cerr << ex.what() << endl;
+        return 1;
+    }
+    return 0;
+}

cpp/DataStorm/clock/config.reader

@@ -0,0 +1,26 @@
+#
+# Use the localhost interface by default for DataStorm endpoints
+#
+Ice.Default.Host=localhost
+
+#
+# DataStorm server endpoint
+#
+#DataStorm.Node.Server.Endpoints=tcp
+
+#
+# DataStorm multicast endpoint
+#
+#DataStorm.Node.Multicast.Endpoints=udp -h 239.255.0.1 -p 10000
+
+#
+# DataStorm Tracing
+#
+#DataStorm.Trace.Topic=1
+#DataStorm.Trace.Data=1
+#DataStorm.Trace.Session=1
+
+#
+# Ice tracing
+#
+#Ice.Trace.Network=1

cpp/DataStorm/clock/config.writer

@@ -0,0 +1,26 @@
+#
+# Use the localhost interface by default for DataStorm endpoints
+#
+Ice.Default.Host=localhost
+
+#
+# DataStorm server endpoint
+#
+#DataStorm.Node.Server.Endpoints=tcp
+
+#
+# DataStorm multicast endpoint
+#
+#DataStorm.Node.Multicast.Endpoints=udp -h 239.255.0.1 -p 10000
+
+#
+# DataStorm Tracing
+#
+#DataStorm.Trace.Topic=1
+#DataStorm.Trace.Data=1
+#DataStorm.Trace.Session=1
+
+#
+# Ice tracing
+#
+#Ice.Trace.Network=1

cpp/DataStorm/clock/msbuild/reader/packages.config

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="zeroc.datastorm.v143" version="1.1.0" targetFramework="native" />
+  <package id="zeroc.ice.v143" version="3.7.8" targetFramework="native" />
+  <package id="zeroc.icebuilder.msbuild" version="5.0.9" targetFramework="native" />
+</packages>