initial commit

7 files changed, 460 insertions, 0 deletions

diff --git a/client/CMakeLists.txt b/client/CMakeLists.txt
new file mode 100644
index 0000000..cd23de8
--- /dev/null
+++ b/client/CMakeLists.txt
@@ -0,0 +1,5 @@
+find_package(Boost REQUIRED COMPONENTS filesystem program_options)
+
+add_executable(client main.cpp)
+target_include_directories(client SYSTEM PRIVATE ${Boost_INCLUDE_DIRS})
+target_link_libraries(client PRIVATE ${Boost_LIBRARIES})
diff --git a/client/client.hpp b/client/client.hpp
new file mode 100644
index 0000000..139ebb2
--- /dev/null
+++ b/client/client.hpp
@@ -0,0 +1,52 @@
+#pragma once
+
+#include "input.hpp"
+#include "settings.hpp"
+#include "transport.hpp"
+
+#include <iostream>
+#include <string>
+#include <utility>
+
+namespace math::client {
+
+class Client {
+public:
+    explicit Client(const Settings& settings)
+        : Client{make_input_reader(settings), make_transport(settings)}
+    { }
+
+    Client(input::ReaderPtr&& input_reader, TransportPtr&& transport)
+        : m_input_reader{std::move(input_reader)}
+        , m_transport{std::move(transport)}
+    { }
+
+    void run() {
+        m_input_reader->for_each_input([this] (const std::string& input) {
+            m_transport->send_query(input, [] (const std::string& reply) {
+                std::cout << reply << '\n';
+            });
+            return true;
+        });
+    }
+
+private:
+    static input::ReaderPtr make_input_reader(const Settings& settings) {
+        if (settings.input_from_string()) {
+            return input::make_string_reader(settings.m_input);
+        }
+        if (settings.input_from_files()) {
+            return input::make_file_reader(settings.m_files);
+        }
+        return input::make_console_reader();
+    }
+
+    static TransportPtr make_transport(const Settings& settings) {
+        return make_blocking_network_transport(settings.m_host, settings.m_port);
+    }
+
+    const input::ReaderPtr m_input_reader;
+    TransportPtr m_transport;
+};
+
+}
diff --git a/client/error.hpp b/client/error.hpp
new file mode 100644
index 0000000..98e1305
--- /dev/null
+++ b/client/error.hpp
@@ -0,0 +1,15 @@
+#pragma once
+
+#include <stdexcept>
+#include <string>
+
+namespace math::client {
+
+class Error : public std::runtime_error {
+public:
+    explicit Error(const std::string& what)
+        : std::runtime_error{"client error: " + what}
+    { }
+};
+
+}
diff --git a/client/input.hpp b/client/input.hpp
new file mode 100644
index 0000000..077d5c7
--- /dev/null
+++ b/client/input.hpp
@@ -0,0 +1,139 @@
+#pragma once
+
+#include "error.hpp"
+
+#include <exception>
+#include <fstream>
+#include <functional>
+#include <iostream>
+#include <memory>
+#include <string>
+#include <vector>
+
+namespace math::client::input {
+
+class Error : public client::Error {
+public:
+    explicit Error(const std::string& what)
+        : client::Error{"input error: " + what} {
+    }
+};
+
+class Reader {
+public:
+    using InputHandler = std::function<bool (const std::string&)>;
+
+    virtual ~Reader() = default;
+
+    virtual bool for_each_input(const InputHandler& process) const = 0;
+};
+
+using ReaderPtr = std::unique_ptr<input::Reader>;
+
+class FileReader : public Reader {
+public:
+    explicit FileReader(const std::string& path)
+        : m_path{path}
+    { }
+
+    bool for_each_input(const InputHandler& process) const override {
+        return enum_lines(process);
+    }
+
+private:
+    bool enum_lines(const InputHandler& process) const {
+        std::ifstream ifs;
+        ifs.exceptions(std::ifstream::badbit);
+
+        try {
+            ifs.open(m_path);
+            if (!ifs.is_open()) {
+                throw Error{"couldn't open file: " + m_path};
+            }
+
+            for (std::string line; std::getline(ifs, line);) {
+                if (!process(line)) {
+                    return false;
+                }
+            }
+        } catch (const std::exception& e) {
+            throw Error{e.what()};
+        }
+
+        return true;
+    }
+
+    const std::string m_path;
+};
+
+class MultiFileReader : public Reader {
+public:
+    explicit MultiFileReader(const std::vector<std::string>& paths)
+        : m_paths{paths}
+    { }
+
+    bool for_each_input(const InputHandler& process) const override {
+        for (const auto& path : m_paths) {
+            const FileReader reader{path};
+            if (!reader.for_each_input(process)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+private:
+    const std::vector<std::string> m_paths;
+};
+
+inline input::ReaderPtr make_file_reader(const std::string& path) {
+    return std::make_unique<input::FileReader>(path);
+}
+
+inline input::ReaderPtr make_file_reader(const std::vector<std::string>& paths) {
+    return std::make_unique<input::MultiFileReader>(paths);
+}
+
+class StringReader : public Reader {
+public:
+    explicit StringReader(const std::string& input)
+        : m_input{input}
+    { }
+
+    bool for_each_input(const InputHandler& process) const override {
+        return process(m_input);
+    }
+
+private:
+    const std::string m_input;
+};
+
+inline input::ReaderPtr make_string_reader(const std::string& input) {
+    return std::make_unique<input::StringReader>(input);
+}
+
+class ConsoleReader : public Reader {
+public:
+    ConsoleReader() = default;
+
+    bool for_each_input(const InputHandler& process) const override {
+        std::string line;
+        while (read_line(line)) {
+            if (!process(line)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+private:
+    static bool read_line(std::string& dest) {
+        return static_cast<bool>(std::getline(std::cin, dest));
+    }
+};
+
+inline input::ReaderPtr make_console_reader() {
+    return std::make_unique<input::ConsoleReader>();
+}
+
+}
diff --git a/client/main.cpp b/client/main.cpp
new file mode 100644
index 0000000..cfe5026
--- /dev/null
+++ b/client/main.cpp
@@ -0,0 +1,34 @@
+#include "client.hpp"
+#include "settings.hpp"
+
+#include <boost/program_options.hpp>
+
+#include <exception>
+#include <iostream>
+
+int main(int argc, char* argv[]) {
+    try {
+        math::client::SettingsParser parser{argv[0]};
+
+        try {
+            const auto settings = parser.parse(argc, argv);
+            if (settings.exit_with_usage()) {
+                parser.usage();
+                return 0;
+            }
+
+            math::client::Client client{settings};
+            client.run();
+        } catch (const boost::program_options::error& e) {
+            parser.usage_error(e);
+            return 1;
+        }
+    } catch (const std::exception& e) {
+        std::cerr << "An error occured: " << e.what() << "\n";
+        return 1;
+    } catch (...) {
+        std::cerr << "An unknown error occured\n";
+        return 1;
+    }
+    return 0;
+}
diff --git a/client/settings.hpp b/client/settings.hpp
new file mode 100644
index 0000000..5c2522e
--- /dev/null
+++ b/client/settings.hpp
@@ -0,0 +1,111 @@
+#pragma once
+
+#include "transport.hpp"
+
+#include <boost/filesystem.hpp>
+#include <boost/program_options.hpp>
+
+#include <exception>
+#include <iostream>
+#include <string>
+#include <vector>
+
+namespace math::client {
+
+struct Settings {
+    std::string m_input;
+    std::string m_host;
+    std::string m_port;
+    std::vector<std::string> m_files;
+
+    bool exit_with_usage() const { return m_vm.count("help"); }
+
+    bool input_from_string() const {
+        return m_vm.count("command");
+    }
+
+    bool input_from_files() const {
+        return !input_from_string() && !m_files.empty();
+    }
+
+    bool input_from_console() const {
+        return !input_from_string() && !input_from_files();
+    }
+
+    boost::program_options::variables_map m_vm;
+};
+
+class SettingsParser {
+public:
+    explicit SettingsParser(const std::string& argv0)
+        : m_prog_name{extract_filename(argv0)}
+    {
+        m_visible.add_options()
+            ("help,h",
+                "show this message and exit")
+            ("command,c",
+                boost::program_options::value(&m_settings.m_input),
+                "evaluate the argument expression and exit")
+            ("host,H",
+                boost::program_options::value(&m_settings.m_host)->default_value("localhost"),
+                "server host address")
+            ("port,p",
+                boost::program_options::value(&m_settings.m_port)->default_value(NetworkTransport::DEFAULT_PORT),
+                "server port number");
+        m_hidden.add_options()
+            ("files",
+                boost::program_options::value<std::vector<std::string>>(&m_settings.m_files),
+                "shouldn't be visible");
+        m_positional.add("files", -1);
+    }
+
+    static const char* get_short_description() {
+        return "[-h|--help] [-c|--command arg] [-H|--host] [-p|--port] [file...]";
+    }
+
+    Settings parse(int argc, char* argv[]) {
+        boost::program_options::options_description all;
+        all.add(m_hidden).add(m_visible);
+        boost::program_options::store(
+            boost::program_options::command_line_parser{argc, argv}
+                .options(all)
+                .positional(m_positional)
+                .run(),
+            m_settings.m_vm);
+        if (m_settings.exit_with_usage()) {
+            return m_settings;
+        }
+        boost::program_options::notify(m_settings.m_vm);
+        return m_settings;
+    }
+
+    void usage() const {
+        std::cout << *this;
+    }
+
+    void usage_error(const std::exception& e) const {
+        std::cerr << "usage error: " << e.what() << '\n';
+        std::cerr << *this;
+    }
+
+private:
+    static std::string extract_filename(const std::string& path) {
+        return boost::filesystem::path{path}.filename().string();
+    }
+
+    const std::string m_prog_name;
+
+    boost::program_options::options_description m_hidden;
+    boost::program_options::options_description m_visible;
+    boost::program_options::positional_options_description m_positional;
+
+    Settings m_settings;
+
+    friend std::ostream& operator<<(std::ostream& os, const SettingsParser& parser) {
+        os << "usage: " << parser.m_prog_name << ' ' << get_short_description() << '\n';
+        os << parser.m_visible;
+        return os;
+    }
+};
+
+}
diff --git a/client/transport.hpp b/client/transport.hpp
new file mode 100644
index 0000000..ae56f73
--- /dev/null
+++ b/client/transport.hpp
@@ -0,0 +1,104 @@
+#pragma once
+
+#include "error.hpp"
+
+#include <boost/asio.hpp>
+#include <boost/system/system_error.hpp>
+
+#include <functional>
+#include <memory>
+#include <string>
+
+namespace math::client {
+namespace transport {
+
+class Error : public client::Error {
+public:
+    explicit Error(const std::string& msg)
+        : client::Error{"transport error: " + msg}
+    { }
+};
+
+}
+
+class Transport {
+public:
+    virtual ~Transport() = default;
+
+    using ProcessResult = std::function<void (const std::string&)>;
+
+    virtual void send_query(const std::string&, const ProcessResult&) = 0;
+};
+
+using TransportPtr = std::unique_ptr<Transport>;
+
+class NetworkTransport : public Transport {
+public:
+    static constexpr auto DEFAULT_PORT = "18000";
+
+    NetworkTransport(const std::string& host, const std::string& port)
+        : m_host{host}, m_port{port}
+    { }
+
+protected:
+    const std::string m_host;
+    const std::string m_port;
+};
+
+class BlockingNetworkTransport : public NetworkTransport {
+public:
+    BlockingNetworkTransport(const std::string &host, const std::string& port)
+        : NetworkTransport{host, port}, m_socket{m_io_context} {
+        try {
+            connect();
+        } catch (const boost::system::system_error& e) {
+            throw transport::Error{e.what()};
+        }
+    }
+
+    void send_query(const std::string& query, const ProcessResult& on_reply) override {
+        std::string reply;
+        try {
+            reply = send_query(query);
+        } catch (const boost::system::system_error& e) {
+            throw transport::Error{e.what()};
+        }
+        on_reply(reply);
+    }
+
+private:
+    void connect() {
+        boost::asio::ip::tcp::resolver resolver{m_io_context};
+        boost::asio::connect(m_socket, resolver.resolve(m_host, m_port));
+    }
+
+    std::string send_query(const std::string& query) {
+        write(query);
+        return read_line();
+    }
+
+    void write(std::string input) {
+        input += '\n';
+        boost::asio::write(m_socket, boost::asio::const_buffer{input.c_str(), input.size()});
+    }
+
+    std::string read_line() {
+        const auto bytes = boost::asio::read_until(m_socket, m_buffer, '\n');
+        const auto data = boost::asio::buffer_cast<const char*>(m_buffer.data());
+        const std::string result{data, bytes - 1};
+        m_buffer.consume(bytes);
+        return result;
+    }
+
+    boost::asio::io_context m_io_context;
+    boost::asio::ip::tcp::socket m_socket;
+    boost::asio::streambuf m_buffer;
+};
+
+inline TransportPtr make_blocking_network_transport(
+    const std::string& host, const std::string& port) {
+
+    return std::make_unique<BlockingNetworkTransport>(host, port);
+}
+
+}