Refactoring of Build framework (#2)

* Updating `conanfile` to use Conan v2

* Updated the build configuration to make the project compile/build again.

* Build now succeeds

* Updated the `$COMMON_UTILS/build` script too (massenz/common_utils`).

* Fixed unit tests build

* Fixed failing tests

* Added `Bucket::operator==` and `Bucket::operator<` to fix a potential bug in the View class.

.gitignore

@@ -31,3 +31,4 @@ bin/test
 .la
 
 cmake-build-debug
+logs/

CMakeLists.txt

@@ -1,18 +1,16 @@
-# This file (c) 2016-2020 AlertAvert.com.  All rights reserved.
+# This file (c) 2016-2024 AlertAvert.com.  All rights reserved.
 
+cmake_minimum_required(VERSION 3.23)
 project(distlib)
-cmake_minimum_required(VERSION 3.16)
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++17 -fPIC")
-
-# Conan Packaging support
-include(${CMAKE_BINARY_DIR}/conanbuildinfo.cmake)
-conan_basic_setup()
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC")
 
 ##
 # Include common cmake utilities.
-# See: https://bitbucket.org/marco/common-utils
+# See: https://github.com/massenz/common-utils
 #
 include(${COMMON_UTILS_DIR}/commons.cmake OPTIONAL RESULT_VARIABLE COMMONS_FILE)
+message(STATUS "Using Common Utilities: ${COMMONS_FILE}")
 
 ##
 # Installation directory; this is both used to access
@@ -23,6 +21,7 @@ include(${COMMON_UTILS_DIR}/commons.cmake OPTIONAL RESULT_VARIABLE COMMONS_FILE)
 if(NOT DEFINED INSTALL_DIR)
     if(DEFINED ENV{INSTALL_DIR})
         set(INSTALL_DIR $ENV{INSTALL_DIR})
+        message(STATUS "INSTALL_DIR set to: ${INSTALL_DIR}")
     else()
         message(FATAL_ERROR
                 "INSTALL_DIR should be defined as an environment variable, or via -D notation")
@@ -33,7 +32,7 @@ endif()
 # Release version management
 #
 set(RELEASE_MAJOR 0)
-set(RELEASE_MINOR 18)
+set(RELEASE_MINOR 20)
 set(RELEASE_PATCH 0)
 
 set(RELEASE "${RELEASE_MAJOR}.${RELEASE_MINOR}.${RELEASE_PATCH}")
@@ -51,11 +50,12 @@ message(STATUS "Building Release: ${RELEASE_STRING} (${CMAKE_BUILD_TYPE})")
 # Both the value of CMAKE_BUILD_TYPE and the `build_type` setting
 # in `~/.conan/profiles/default` need to match.
 #
-if(${CMAKE_BUILD_TYPE} STREQUAL "Debug")
-    set(GLOG glogd)
-else()
-    set(GLOG glog)
-endif()
+# TODO: review to confirm whether this is still necessary with Conan V2
+#if(${CMAKE_BUILD_TYPE} STREQUAL "Debug")
+#    set(GLOG glogd)
+#else()
+#    set(GLOG glog)
+#endif()
 
 set(SOURCE_DIR ${PROJECT_SOURCE_DIR}/src)
 set(INCLUDE_DIR ${PROJECT_SOURCE_DIR}/include)
@@ -75,10 +75,10 @@ include_directories(
         ${INSTALL_DIR}/include
 )
 
-link_directories(
-        ${INSTALL_DIR}/lib
-        ${PROJECT_BINARY_DIR}/lib
-)
+#link_directories(
+#        ${INSTALL_DIR}/lib
+#        ${PROJECT_BINARY_DIR}/lib
+#)
 
 set(UTILS_SOURCES
         ${SOURCE_DIR}/utils/misc.cpp
@@ -91,9 +91,16 @@ set(SOURCES
         ${SOURCE_DIR}/View.cpp
 )
 
-set(UTILS_LIBS
-        crypto
-        ${GLOG}
+# Add Conan build folder to CMAKE_PREFIX_PATH for dependency resolution
+list(APPEND CMAKE_PREFIX_PATH "${CMAKE_BINARY_DIR}")
+
+find_package(cryptopp REQUIRED)
+find_package(glog)
+find_package(OpenSSL REQUIRED)
+set(LIBS
+        cryptopp::cryptopp
+        glog::glog
+        openssl::openssl
         pthread
 )
 
@@ -106,7 +113,7 @@ add_library(distutils SHARED
         ${SOURCES}
         ${UTILS_SOURCES}
 )
-target_link_libraries(distutils ${UTILS_LIBS})
+target_link_libraries(distutils ${LIBS})
 
 
 ##
@@ -126,20 +133,21 @@ add_subdirectory(${TESTS_DIR})
 
 set(EXAMPLES_DIR ${SOURCE_DIR}/examples)
 
-# Examples will use the latest build for the shared libraries
+message(STATUS "Libraries will be linked from
+    ${CMAKE_BINARY_DIR} and ${INSTALL_DIR}/lib")
 link_directories(
-        ${CMAKE_BINARY_DIR}/lib
+        ${CMAKE_BINARY_DIR}
         ${INSTALL_DIR}/lib
 )
 
 ##
 # Merkle Tree Demo
 #
 add_executable(merkle_demo ${EXAMPLES_DIR}/merkle_demo.cpp)
-target_link_libraries(merkle_demo distutils ${UTILS_LIBS})
+target_link_libraries(merkle_demo distutils ${LIBS})
 
 ##
 # KeyValue Store Demo
 #
 add_executable(keystore_demo ${EXAMPLES_DIR}/keystore_example.cpp)
-target_link_libraries(keystore_demo distutils ${UTILS_LIBS})
+target_link_libraries(keystore_demo distutils ${LIBS})

CMakeLists.txt.example

@@ -0,0 +1,9 @@
+cmake_minimum_required(VERSION 3.15)
+project(MyProject)
+
+# Find the glog package installed by Conan
+find_package(glog REQUIRED)
+
+# Set up the target and link glog
+add_executable(use-glog src/examples/use_glog.cpp)
+target_link_libraries(use-glog PRIVATE glog::glog)

CMakeUserPresets.json

@@ -4,6 +4,7 @@
         "conan": {}
     },
     "include": [
-        "build/CMakePresets.json"
+        "build/Release/generators/CMakePresets.json",
+        "build/Debug/generators/CMakePresets.json"
     ]
 }

README.md

@@ -29,21 +29,42 @@ A detailed description of the library's features follows the [Install & build](#
 
 ## Build & testing
 
+The sequence of commands to build the project:
+
+```shell
+conan install . -s build_type=Debug --build=missing
+cmake --preset conan-debug -DCOMMON_UTILS=$COMMON_UTILS
+cmake --build --preset conan-debug -DCOMMON_UTILS_DIR=$COMMON_UTILS
+```
+The build targets are currently just `distutils` lib and the `merkle_demo` and
+`keystore_demo` examples, in the `build/Debug` directory:
+
+```shell
+./build/Debug/merkle_demo "this is the string to hash"
+```
+
+For the `Release` build, use the `conan-release` preset and `Release` build type.
+See [#Common utilities](#common-utilities) for a simpler way.
+
 ### Common utilities
 
-The build/test scripts in this repository take advantage of shared common utility functions in [this common utils repository](https://bitbucket.org/marco/common-utils): clone it
-somewhere, and make `$COMMON_UTILS_DIR` point to it:
+The build/test scripts in this repository take advantage of shared common utility functions in
+[the Common Utils repository](https://bitbucket.org/marco/common-utils): follow the instructions there to install the utilities and  
+set the `COMMON_UTILS` environment variable to point to the directory where you installed them.
+
+That is done as part of the installation process anyway:
 
 ```shell
-git clone [email protected]:marco/common-utils.git
-export COMMON_UTILS_DIR="$(pwd)/common-utils"
+export COMMON_UTILS=/path/to/common-utils
+export VERSION=...
+curl -s -L https://cdn.githubraw.com/massenz/common-utils/$VERSION/install.sh | zsh -s
 ```
 
 To build/test the project, link to the scripts there:
 
 ```shell
-ln -s ${COMMON_UTILS_DIR}/build.sh build && \
-    ln -s ${COMMON_UTILS_DIR}/test.sh test
+ln -s ${COMMON_UTILS_DIR}/build.sh bin/build && \
+    ln -s ${COMMON_UTILS_DIR}/test.sh bin/test
 ```
 
 ### Build & Install libdistutils.so

conanfile.txt

@@ -9,12 +9,12 @@ glog/0.4.0
 gtest/1.15.0
 openssl/3.3.2
 #protobuf/5.27.0
-zeromq/4.3.5
+#cppzmq/4.10.0
 
 [options]
 glog/*:with_gflags=False
 gtest/*:shared=False
-protobuf/*:shared=True
+#protobuf/*:shared=True
 
 [imports]
 #
@@ -24,10 +24,13 @@ protobuf/*:shared=True
 # This is useful for the `install` step to move them to $INSTALL_DIR
 # if defined.
 #
-lib, *.dylib* -> ./lib
-lib, *.so* -> ./lib
-include, * -> ./include
+#lib, *.dylib* -> ./lib
+#lib, *.so* -> ./lib
+#include, * -> ./include
 
 [generators]
 CMakeDeps
 CMakeToolchain
+
+[layout]
+cmake_layout

include/Bucket.hpp

@@ -3,7 +3,6 @@
 
 #pragma once
 
-
 #include <memory>
 #include <string>
 #include <utility>
@@ -14,6 +13,14 @@
 #include "json.hpp"
 
 using json = nlohmann::json;
+class Bucket;
+
+/**
+ * Utility function to stream a string representation of a bucket.
+ *
+ * @return the passed in stream, to which the bucket has been streamed to.
+ */
+std::ostream& operator<<(std::ostream& out, const Bucket &bucket);
 
 /**
  * A "bucket" abstracts the concept of a hashed partition, using consistent hashing.
@@ -79,15 +86,15 @@ class Bucket {
    *
    * @return the set of {@link partitions()} points that define this bucket
    */
-  std::vector<float> partition_points() const {
+  [[nodiscard]] std::vector<float> partition_points() const {
     return hash_points_;
   }
 
-  float partition_point(int i) const {
+  [[nodiscard]] float partition_point(int i) const {
     if (i < 0 || i >= partitions()) {
       std::ostringstream msg;
-      msg << "Out of bound: requesting partition point #" << i << ", when only "
-           << partitions() << " are available ('" << name_ << "')";
+      msg << "Requesting partition point #" << i << ", when only "
+           << partitions() << " are available in " << *this;
       throw std::out_of_range(msg.str());
     }
     return hash_points_[i];
@@ -103,17 +110,29 @@ class Bucket {
    *
    * @param x a point in the [0, 1] interval.
    * @return a pair of {index, point} values that determine which partition point is
-   *    the immediately greater than `x`.
+   *    the one immediately greater than `x`.
    */
-  std::pair<int, float> partition_point(float x) const;
+  [[nodiscard]] std::pair<int, float> partition_point(float x) const;
 
-  int partitions() const { return hash_points_.size(); }
+  [[nodiscard]] int partitions() const { return hash_points_.size(); }
 };
 
 
+
 /**
- * Utility function to stream a string representation of a bucket.
+ * Equality operator for `Bucket` objects.
+ * Uses the name and partition points to determine equality.
  *
- * @return the passed in stream, to which the bucket has been streamed to.
+ * This method actully uses the ordering operator to compare the two buckets, using
+ * the usual approach that (a == b) iff !(a < b) && !(b < a).
  */
-std::ostream& operator<<(std::ostream& out, const Bucket &bucket);
+bool operator==(const Bucket &lhs, const Bucket &rhs);
+
+/**
+ * Ordering operator for `Bucket` objects.
+ * Uses the name and partition points to define a total order on the Buckets.
+ *
+ * To compare partition points (which are floats), we use a tolerance of 1e-6.
+ * TODO: this should actually be a configurable (static) attribute of the class.
+ */
+bool operator<(const Bucket &lhs, const Bucket &rhs);

include/ConsistentHash.hpp

@@ -42,17 +42,15 @@ float consistent_hash(const std::string &msg);
  *
  * See Item 40 of Effective STL.
  */
-template <int Tolerance = 5>
-class FloatLessWithTolerance :
-    public std::binary_function<float, float, bool> {
-
-  double epsilon_;
- public:
-  FloatLessWithTolerance() {
-    epsilon_ = pow(10, -Tolerance);
-  }
-
-  bool operator()( const float &left, const float &right  ) const {
-    return (std::abs(left - right) > epsilon_) && (left < right);
-  }
+template<int Tolerance = 5>
+class FloatLessWithTolerance {
+public:
+    explicit FloatLessWithTolerance(double eps = pow(10, -Tolerance)) : epsilon_(eps) { }
+
+    bool operator()(const float &left, const float &right) const {
+        return (std::abs(left - right) > epsilon_) && (left < right);
+    }
+
+private:
+    double epsilon_;
 };