Remote Packages and Repositories ################################ .. highlight:: bash ``dds`` stores a local database of available packages, along with their dependency statements and information about how a source distribution thereof may be obtained. Inside the database are *package repositories*, which are remote servers that contain their own database of packages, and may also contain the packages themselves. An arbitrary number of package repositories may be added to the local database. When ``dds`` updates its package information, it will download the package database from each registered remote and import the listings into its own local database, making them available for download. Viewing Available Packages ************************** The default catalog database is stored in a user-local location, and the available packages can be listed with ``dds pkg search``:: $ dds pkg search Name: abseil Versions: 2018.6.0, 2019.8.8, 2020.2.25 From: repo-1.dds.pizza Name: asio Versions: 1.12.0, 1.12.1, 1.12.2, 1.13.0, 1.14.0, 1.14.1, 1.16.0, 1.16.1 From: repo-1.dds.pizza Name: boost.leaf Versions: 0.1.0, 0.2.0, 0.2.1, 0.2.2, 0.2.3, 0.2.4, 0.2.5, 0.3.0 From: repo-1.dds.pizza Name: boost.mp11 Versions: 1.70.0, 1.71.0, 1.72.0, 1.73.0 From: repo-1.dds.pizza Optionally, one can search with a glob/fnmatch-style pattern:: $ dds pkg search 'neo-*' Name: neo-buffer Versions: 0.2.1, 0.3.0, 0.4.0, 0.4.1, 0.4.2 From: repo-1.dds.pizza Name: neo-compress Versions: 0.1.0, 0.1.1, 0.2.0 From: repo-1.dds.pizza Name: neo-concepts Versions: 0.2.2, 0.3.0, 0.3.1, 0.3.2, 0.4.0 From: repo-1.dds.pizza Remote Repositories ******************* A remote package repository consists of an HTTP(S) server serving the following: 1. An accessible directory containing source distributions of various packages, and 2. An accessible database file that contains a listing of packages and some repository metadata. The exact details of the directory layout and database are not covered here, and are not necessary to make use of a repository. When ``dds`` uses a repository, it pulls down the database file and imports its contents into its own local database, associating the imported package listings with the remote repository which provides them. Pulling the entire database at once allows ``dds`` to perform much faster dependency resolution and reduces the round-trips associated with using a dynamic package repository. Adding a Repository =================== Adding a remote repository to the local database is a simple single command:: $ dds pkg repo add "https://repo-1.dds.pizza" [info ] Pulling repository contents for repo-1.dds.pizza [https://repo-1.dds.pizza/] This will tell ``dds`` to add ``https://repo-1.dds.pizza`` as a remote repository and immediately pull its package listings for later lookup. This initial update can be suppressed with the ``--no-update`` flag. .. note:: After the initial ``pkg repo add``, the repository is *not* identified by its URL, but by its *name*, which is provided by the repository itself. The name is printed the first time it is added, and can be seen using ``pkg repo ls``. Listing Repositories ==================== A list of package repositories can be seen with the ``pkg repo ls`` subcommand:: $ dds pkg repo ls Removing Repositories ===================== A repository can be removed by the ``pkg repo remove`` subcommand:: $ dds pkg repo remove Where ```` is given as the *name* (not URL!) of the repository. **Note** that removing a repository will make all of its corresponding remote packages unavailable, while packages that have been pulled into the local cache will remain available even after removing a repository. Updating Repository Data ======================== Repository data and package listings can be updated with the ``pkg repo update`` subcommand:: $ dds pkg repo update This will pull down the databases of all registered remote repositories. If ``dds`` can detect that a repository's database is unchanged since a prior update, that update will be skipped. The Default Repository ********************** When ``dds`` first initializes its local package database, it will add a single remote repository: ``https://repo-1.dds.pizza/``, which has the name ``repo-1.dds.pizza``. At the time of writing, this is the only official ``dds`` repository, and is populated sparsely with hand-curated and prepared packages. In the future, the catalog of packages will grow and be partially automated. There is nothing intrinsically special about this repository other than it being the default when ``dds`` first creates its package database. It can be removed as any other, should one want tighter control over package availability. Managing a Repository ********************* A ``dds`` repository is simply a directory of static files, so any HTTP server that can serve from a filesystem can be used as a repository. ``dds`` also ships with a subcommand, ``repoman``, that can be used to manage a repository directory. Initializing a Repository ========================= Before anything can be done, a directory should be converted to a repository by using ``repoman init``:: $ dds repoman init ./my-repo-dir --name=my-experimental-repo This will add the basic metadata into ``./my-repo-dir`` such that ``dds`` will be able to pull package data from it. The ``--name`` argument should be used to give the repository a unique name. The name should be globally unique to avoid collisions: When ``dds`` pulls a repository that declares a given name, it will *replace* the package listings associated with any repository of that name. As such, generic names like ``main`` or ``packages`` shouldn't be used in production. Listing Contents ================ The packages in a repository can be listed using ``dds repoman ls ``. This will simply print each package identifier that is present in the repository. Importing Source Distributions ============================== If you have a source distribution archive, it can be imported with the appropriately named ``dds repoman import`` command:: $ dds repoman import ./my-repo some-pkg@1.2.3.tar.gz Multiple archive paths may be provided to import them all at once. Adding a Package by URL ======================= A repository can also list packages that it does not host itself. Such a package listing can be added "by URL," where the URL tells ``dds`` how to pull the source distribution of the package. Beyond basic HTTP(S) URLs, ``dds`` can also clone packages via ``git``:: $ dds repoman add ./my-repo git+https://github.com/vector-of-bool/neo-fun.git#0.5.2 The above URL tells ``dds`` that it can use ``git clone`` against ``https://github.com/vector-of-bool/neo-fun.git`` and ask for tag ``0.5.2`` to get a source distribution directory that can be imported. Note the fragment on ``git`` URLs! The fragment is required to specify the branch or tag to clone. If the package is available on GitHub, ``dds`` has a shorthand URL for that:: $ dds repoman add ./my-repo github:vector-of-bool/neo-fun/0.6.0 The ``github:`` URL scheme tells ``dds`` to clone from GitHub. A ``github:`` URL must have exactly three path elements to determine *what* to download: ``github:{owner}/{repository}/{branch-or-tag}``. .. note:: The ``github:`` URL lacks an *authority* element, and as such *does not* use the double-slash. .. note:: ``repoman add`` will immediately attempt to pull a source distribution from the given URL so that it may import the package's metadata into its listing database. You cannot add a URL that is not already accessible. Removing Packages ================= A package can be removed from a repository with ``dds repoman remove ``, where ```` is the ``@`` of the package to remove.