Chose a syntaxe to store "wich packages should be sync"

[Rignchen]

If we want to synchronize packages between 2 computers, we need to know how what packages to install however

• Sometimes you want to use a specific package manager over another one
• Some packages aren't available on some os or have another name
• Sometimes you need 2 packages to substitute 1 none existing package

For these reasons I thing the syntax we chose should support

• Having a list of all packages to install
• Having alternatives for each package
• Being able to specify multiple packages to install per alternative
• Being able to specify which alternative should be chosen depending on the operating system
• Choosing the package manager to use for the installation of the package

[Rignchen]

I suggest to use a json like this one which does support all features above (comments are here to explain which part of the json is responsible of what but won't be there in the file)

[ // List of all packages to install
    [ // List of alternative
        {
            "os": ["Os1", "Os2", "Os3"], // List of operating system where this alternative should be chosen
            "packages": [ // List of packages contained in this alternative
                {
                    "name": "package1", // Name of the package
                    "package_manager": { // Package manager used to install the package on the operating system
                        "Os1": "package_manager1",
                        "Os2": "package_manager2",
                        "Os3": "package_manager3"
                    }
                }
            ]
        }
    ]
]

or to use a yml equivalent

- - os:
    - Os1
    - Os2
    - Os3
    packages:
    - name: package1
      package_manager:
        Os1: package_manager1
        Os2: package_manager2
        Os3: package_manager3

Now this may seems really verbose but in most case there won't be multiple alternative with a dedicated package_manager for each operating system so some parts of it are optional:

• The whole alternative list can be replaced by the name of the package if there is only one alternative and no need to specify the package manager
• The os list can be removed if the package is available on all operating system
• The package_manager can be removed if it is not necessary to specify the package manager for a specific operating system
• Each line of the package_manager can be removed if the package manager is the default one for the operating system

Of course the json here is in nice format but it will be stored as 1 line without insignificant white-space to reduce storage taken on the user's disk