I am very much confused between these two terms Build tools and Package Manager. According to my current knowledge, Package managers are the ones use to install dependencies required for the code to execute while Build tools are used to Package the code plus dependencies into single file i.e. building the code. Building our application will enable to make it production ready.
Am I right???
Short answer
Build systems/tools manage your compilation requirements.
Package managers/tools manager your library requirements.
A build tool may have integrated package management.
For example, in both C++ and Java you can directly call the compiler and provide all the include, source and library paths manually or you can use a build system (make/cmake... for c++, maven/gradle/ant... for java).
When you link external libraries with your build system it will do its best to find them in its search path, and will link with the first version that meets its requirements or tell you that it couldn't find it. Adding libraries manually is fairly easy, but sometimes each library you add will require another library with it.
A package manager would make sure that your libraries are downloaded, are the right version, and all the libraries they depend on are downloaded. some examples are maven and gradle which have integrated package managment for java, and conan is a fairly popular option to combine with cmake.
So ideally you would use both, but it can be more work setting them up than you save not doing things manually. It depends on your programming language, if you need multiple versions of something, and your OS.
Related
I'm trying to create a Flutter plugin which wraps some C++ code. That code has multiple dependencies, so steps need to be taken to provide those dependencies to the C++ build system (currently based on cmake, building for windows desktop), particularly where to find headers and libraries. There are a number of ways to do this with CMake, and we happen to be using Conan to fetch and provided dependencies, but in any case, I need a way to do a pre-build step and/or provide arguments to Flutter's execution of cmake to help it locate these dependencies.
I have ascertained that Flutter doesn't support a lot of (or any) customizability of the build. There are the build and build_runner packages, but I don't believe they will have knowledge of the build output directory for my platform nor provide a way to inject arguments to the cmake invocation.
How can I feed dependencies to the native build of the Flutter plugin? These dependencies may be static or dynamic libraries.
The only possible official way to interop with C/C++ code is ffi library. There is not much info about it online, but there is the official documentation.
Keep in mind that C-interop is parent platform dependent.
To properly generate binding with the needed native code, you have ffigen library. I think it will also help you with your dependencies issue.
Hope it helps
I'm a DevOps engineer creating CI processes for projects. I was wondering what is the best way to deal with the following scenario: Let's say I have a C++ project (using CLion + CMake) with several developers working on it. Now in order to be built, the project has some libraries it depends on. That automatically reflects on the CMakeLists.txt file that should know where to look for those libraries.
Basically the problem is that we need to take care that every developer has these libraries in the correct paths on his machine, which is a big hassle.
One approach to handle this would be to keep those dependencies in the repository. That's great since all the developer has to do is to clone the repo and he got everything he needs in order to run compilation. But as we know, keeping binaries in SCM is not a good practice.
The question is, is there a good method to handle project dependencies in a C++ project?
I know that with C# for example, we could use NuGet packages to handle these kind of scenarios. So we'd have a NuGet repository in Artifactory that would host the dependency packages, and then in our project we'd keep a reference to the required packages, and in build time we would just download the dependecies and build the project.
Is there something alike in C++ (Running on Linux I mean)?
Hope the question is clear enough lol, had a hard time wording it..
It depends on how those dependencies are delivered and packaged. If whoever maintains your dependencies took CMake into account you can probably use find_package. If they didn't account for this, but they support pkg-config you can use FindPkgConfig. Now all you need to do is let the developers know what dependencies they need to install. This should work regardless of the OS used for development.
Other solutions may involve pulling and building the dependency code when you build your project (for example, by using git submodules if possible, or FetchContent, but this can become a nightmare if you have a lot of dependencies).
Additionally, you can try using a package manager like vcpkg, or conan (if all your dependencies are available there), or CPM.
I am learning C++, is there something like python-pip in C++? I am uing json/YAML packages in my 1st project, I want to know which is the correct way to manage dependencies in my project, and after I finished developing, which is the correct way to migrate dependencies to production environment?
C++ doesn't have a standard package manager or build system: this is one of the major pain points of the language. You have a few options:
Manually install dependencies when required.
Use your OS's package manager.
Adopt a third-party package manager such as conan.io.
None of the above solutions is perfect and dependency management will likely always require some more effort on your part compared to languages such as Python or Rust.
As far as I know, there is no central library management system in C++ similar to pip. You need to download and install the packages you need manually or through some package manager if your OS supports it.
As for managing multiple libraries in a C++ project, you could use CMAKE or something similar. If you link your libraries dynamically (i.e., though .dll or .so files), then you need to supply these dynamic library binaries along with your application. To find out which dll files may be needed, you could something like the Dependency Walker or ELF Library Viewer.
Personally, I use a development environment - specifically Qt (with the QtCreator), containing many of these components like qmake etc. - which simplifies the process of development and distribution.
There are already some questions about dependency managers here, but it seems to me that they are mostly about build systems, while I am looking for something targeted purely at making dependency tracking and resolution simpler (and I'm not necessarily interested in learning a new build system).
So, typically we have a project and some common code with another project. This common code is organized as a library, so when I want to get the latest code version for a project, I should also go get all the libraries from the source control. To do this, I need a list of dependencies. Then, to build the project I can reuse this list too.
I've looked at Maven and Ivy, but I'm not sure if they would be appropriate for C++, as they look quite heavily java-targeted (even though there might be plugins for C++, I haven't found people recommending them).
I see it as a GUI tool producing some standardized dependency list which can then be parsed by different scripts etc. It would be nice if it could integrate with source control (tag, get a tagged version with dependencies etc), but that's optional.
Would you have any suggestions? Maybe I'm just missing something, and usually it's done some other way with no need for such a tool? Thanks.
You can use Maven in relationship with C++ in two ways. First you can use it for dependency management of components between each other. Second you can use Maven-nar-plugin for creating shared libraries and unit tests in relationship with boost library (my experience). In the end you can create RPM's (maven-rpm-plugin) out of it to have adequate installation medium. Furthermore i have created the installation for CI environment via Maven (RPM's for Hudson, Nexus installation in RPM's).
I'm not sure if you would see an version control system (VCS) as build tool but Mercurial and Git support sub-repositories. In your case a sub-repository would be your dependencies:
Join multiple subrepos into one and preserve history in Mercurial
Multiple git repo in one project
Use your VCS to archive the build results -- needed anyway for maintenance -- and refer to the libs and header files in your build environment.
If you are looking for a reference take a look at https://android.googlesource.com/platform/manifest.
I'm in the middle of setting up an build environment for a c++ game project. Our main requirement is the ability to build not just our game code, but also its dependencies (Ogre3D, Cegui, boost, etc.). Furthermore we would like to be able build on Linux as well as on Windows as our development team consists of members using different operating systems.
Ogre3D uses CMake as its build tool. This is why we based our project on CMake too so far. We can compile perfectly fine once all dependencies are set up manually on each team members system as CMake is able to find the libraries.
The Question is if there is an feasible way to get the dependencies set up automatically. As a Java developer I know of Maven, but what tools do exist in the world of c++?
Update: Thanks for the nice answers and links. Over the next few days I will be trying out some of the tools to see what meets our requirements, starting with CMake. I've indeed had my share with autotools so far and as much as I like the documentation (the autobook is a very good read), I fear autotools are not meant to be used on Windows natively.
Some of you suggested to let some IDE handle the dependency management. We consist of individuals using all possible technologies to code from pure Vim to fully blown Eclipse CDT or Visual Studio. This is where CMake allows use some flexibility with its ability to generate native project files.
In the latest CMake 2.8 version there is the new ExternalProject module.
This allows to download/checkout code, configure and build it as part of your main build tree.
It should also allow to set dependencies.
At my work (medical image processing group) we use CMake to build all our own libraries and applications. We have an in-house tool to track all the dependencies between projects (defined in a XML database). Most of the third party libraries (like Boost, Qt, VTK, ITK etc..) are build once for each system we support (MSWin32, MSWin64, Linux32 etc..) and are commited as zip-files in the version control system. CMake will then extract and configure the correct zip file depending on which system the developer is working on.
I have been using GNU Autotools (Autoconf, Automake, Libtool) for the past couple of months in several projects that I have been involved in and I think it works beautifully. Truth be told it does take a little bit to get used to the syntax, but I have used it successfully on a project that requires the distribution of python scripts, C libraries, and a C++ application. I'll give you some links that helped me out when I first asked a similar question on here.
The GNU Autotools Page provides the best documentation on the system as a whole but it is quite verbose.
Wikipedia has a page which explains how everything works. Autoconf configures the project based upon the platform that you are about to compile on, Automake builds the Makefiles for your project, and Libtool handles libraries.
A Makefile.am example and a configure.ac example should help you get started.
Some more links:
http://www.lrde.epita.fr/~adl/autotools.html
http://www.developingprogrammers.com/index.php/2006/01/05/autotools-tutorial/
http://sources.redhat.com/autobook/
One thing that I am not certain on is any type of Windows wrapper for GNU Autotools. I know you are able to use it inside of Cygwin, but as for actually distributing files and dependencies on Windows platforms you are probably better off using a Windows MSI installer (or something that can package your project inside of Visual Studio).
If you want to distribute dependencies you can set them up under a different subdirectory, for example, libzip, with a specific Makefile.am entry which will build that library. When you perform a make install the library will be installed to the lib folder that the configure script determined it should use.
Good luck!
There are several interesting make replacements that automatically track implicit dependencies (from header files), are cross-platform and can cope with generated files (e.g. shader definitions). Two examples I used to work with are SCons and Jam/BJam.
I don't know of a cross-platform way of getting *make to automatically track dependencies.
The best you can do is use some script that scans source files (or has C++ compiler do that) and finds #includes (conditional compilation makes this tricky) and generates part of makefile.
But you'd need to call this script whenever something might have changed.
The Question is if there is an feasible way to get the dependencies set up automatically.
What do you mean set up?
As you said, CMake will compile everything once the dependencies are on the machines. Are you just looking for a way to package up the dependency source? Once all the source is there, CMake and a build tool (gcc, nmake, MSVS, etc.) is all you need.
Edit: Side note, CMake has the file command which can be used to download files if they are needed: file(DOWNLOAD url file [TIMEOUT timeout] [STATUS status] [LOG log])
Edit 2: CPack is another tool by the CMake guys that can be used to package up files and such for distribution on various platforms. It can create NSIS for Windows and .deb or .tgz files for *nix.
At my place of work (we build embedded systems for power protection) we used CMake to solve the problem. Our setup allows cmake to be run from various locations.
/
CMakeLists.txt "install precompiled dependencies and build project"
project/
CMakeLists.txt "build the project managing dependencies of subsystems"
subsystem1/
CMakeLists.txt "build subsystem 1 assume dependecies are already met"
subsystem2/
CMakeLists.txt "build subsystem 2 assume dependecies are already met"
The trick is to make sure that each CMakeLists.txt file can be called in isolation but that the top level file can still build everything correctly. Technically we don't need the sub CMakeLists.txt files but it makes the developers happy. It would be an absolute pain if we all had to edit one monolithic build file at the root of the project.
I did not set up the system (I helped but it is not my baby). The author said that the boost cmake build system had some really good stuff in it, that help him get the whole thing building smoothly.
On many *nix systems, some kind of package manager or build system is used for this. The most common one for source stuff is GNU Autotools, which I've heard is a source of extreme grief. However, with a few scripts and an online depository for your deps you can set up something similar like so:
In your project Makefile, create a target (optionally with subtargets) that covers your dependencies.
Within the target for each dependency, first check to see if the dep source is in the project (on *nix you can use touch for this, but you could be more thorough)
If the dep is not there, you can use curl, etc to download the dep
In all cases, have the dep targets make a recursive make call (make; make install; make clean; etc) to the Makefile (or other configure script/build file) of the dependency. If the dep is already built and installed, make will return fairly promptly.
There are going to be lots of corner cases that will cause this to break though, depending on the installers for each dep (perhaps the installer is interactive?), but this approach should cover the general idea.
Right now I'm working on a tool able to automatically install all dependencies of a C/C++ app with exact version requirement :
compiler
libs
tools (cmake, autotools)
Right now it works, for my app. (Installing UnitTest++, Boost, Wt, sqlite, cmake all in correct order)
The tool, named «C++ Version Manager» (inspired by the excellent ruby version manager), is coded in bash and hosted on github : https://github.com/Offirmo/cvm
Any advices and suggestions are welcomed.