github.com/brandon-bethke-neudesic/moby@v1.13.1/ROADMAP.md (about)

     1  Docker Engine Roadmap
     2  =====================
     3  
     4  ### How should I use this document?
     5  
     6  This document provides description of items that the project decided to prioritize. This should
     7  serve as a reference point for Docker contributors to understand where the project is going, and
     8  help determine if a contribution could be conflicting with some longer terms plans.
     9  
    10  The fact that a feature isn't listed here doesn't mean that a patch for it will automatically be
    11  refused (except for those mentioned as "frozen features" below)! We are always happy to receive
    12  patches for new cool features we haven't thought about, or didn't judge priority. Please however
    13  understand that such patches might take longer for us to review.
    14  
    15  ### How can I help?
    16  
    17  Short term objectives are listed in the [wiki](https://github.com/docker/docker/wiki) and described
    18  in [Issues](https://github.com/docker/docker/issues?q=is%3Aopen+is%3Aissue+label%3Aroadmap). Our
    19  goal is to split down the workload in such way that anybody can jump in and help. Please comment on
    20  issues if you want to take it to avoid duplicating effort! Similarly, if a maintainer is already
    21  assigned on an issue you'd like to participate in, pinging him on IRC or GitHub to offer your help is
    22  the best way to go.
    23  
    24  ### How can I add something to the roadmap?
    25  
    26  The roadmap process is new to the Docker Engine: we are only beginning to structure and document the
    27  project objectives. Our immediate goal is to be more transparent, and work with our community to
    28  focus our efforts on fewer prioritized topics.
    29  
    30  We hope to offer in the near future a process allowing anyone to propose a topic to the roadmap, but
    31  we are not quite there yet. For the time being, the BDFL remains the keeper of the roadmap, and we
    32  won't be accepting pull requests adding or removing items from this file.
    33  
    34  # 1. Features and refactoring
    35  
    36  ## 1.1 Runtime improvements
    37  
    38  We recently introduced [`runC`](https://runc.io) as a standalone low-level tool for container
    39  execution. The initial goal was to integrate runC as a replacement in the Engine for the traditional
    40  default libcontainer `execdriver`, but the Engine internals were not ready for this.
    41  
    42  As runC continued evolving, and the OCI specification along with it, we created
    43  [`containerd`](https://containerd.tools/), a daemon to control and monitor multiple `runC`. This is
    44  the new target for Engine integration, as it can entirely replace the whole `execdriver`
    45  architecture, and container monitoring along with it.
    46  
    47  Docker Engine will rely on a long-running `containerd` companion daemon for all container execution
    48  related operations. This could open the door in the future for Engine restarts without interrupting
    49  running containers.
    50  
    51  ## 1.2 Plugins improvements
    52  
    53  Docker Engine 1.7.0 introduced plugin support, initially for the use cases of volumes and networks
    54  extensions. The plugin infrastructure was kept minimal as we were collecting use cases and real
    55  world feedback before optimizing for any particular workflow.
    56  
    57  In the future, we'd like plugins to become first class citizens, and encourage an ecosystem of
    58  plugins. This implies in particular making it trivially easy to distribute plugins as containers
    59  through any Registry instance, as well as solving the commonly heard pain points of plugins needing
    60  to be treated as somewhat special (being active at all time, started before any other user
    61  containers, and not as easily dismissed).
    62  
    63  ## 1.3 Internal decoupling
    64  
    65  A lot of work has been done in trying to decouple the Docker Engine's internals. In particular, the
    66  API implementation has been refactored, and the Builder side of the daemon is now
    67  [fully independent](https://github.com/docker/docker/tree/master/builder) while still residing in
    68  the same repository.
    69  
    70  We are exploring ways to go further with that decoupling, capitalizing on the work introduced by the
    71  runtime renovation and plugins improvement efforts. Indeed, the combination of `containerd` support
    72  with the concept of "special" containers opens the door for bootstrapping more Engine internals
    73  using the same facilities.
    74  
    75  ## 1.4 Cluster capable Engine
    76  
    77  The community has been pushing for a more cluster capable Docker Engine, and a huge effort was spent
    78  adding features such as multihost networking, and node discovery down at the Engine level. Yet, the
    79  Engine is currently incapable of taking scheduling decisions alone, and continues relying on Swarm
    80  for that.
    81  
    82  We plan to complete this effort and make Engine fully cluster capable. Multiple instances of the
    83  Docker Engine being already capable of discovering each other and establish overlay networking for
    84  their container to communicate, the next step is for a given Engine to gain ability to dispatch work
    85  to another node in the cluster. This will be introduced in a backward compatible way, such that a
    86  `docker run` invocation on a particular node remains fully deterministic.
    87  
    88  # 2 Frozen features
    89  
    90  ## 2.1 Docker exec
    91  
    92  We won't accept patches expanding the surface of `docker exec`, which we intend to keep as a
    93  *debugging* feature, as well as being strongly dependent on the Runtime ingredient effort.
    94  
    95  ## 2.2 Remote Registry Operations
    96  
    97  A large amount of work is ongoing in the area of image distribution and provenance. This includes
    98  moving to the V2 Registry API and heavily refactoring the code that powers these features. The
    99  desired result is more secure, reliable and easier to use image distribution.
   100  
   101  Part of the problem with this part of the code base is the lack of a stable and flexible interface.
   102  If new features are added that access the registry without solidifying these interfaces, achieving
   103  feature parity will continue to be elusive. While we get a handle on this situation, we are imposing
   104  a moratorium on new code that accesses the Registry API in commands that don't already make remote
   105  calls.
   106  
   107  Currently, only the following commands cause interaction with a remote registry:
   108  
   109    - push
   110    - pull
   111    - run
   112    - build
   113    - search
   114    - login
   115  
   116  In the interest of stabilizing the registry access model during this ongoing work, we are not
   117  accepting additions to other commands that will cause remote interaction with the Registry API. This
   118  moratorium will lift when the goals of the distribution project have been met.