simple streams
==============

.. A single sentence that says what the product is, succinctly and memorably

simplestreams is an on-disk format and associated tooling to securely convey
and mirror artifacts and/or their metadata that change over time in a
structured way.

.. A paragraph of one to three short sentences, that describe what the product
   does.

An artifact might be a software release, a disk image or any other data blob or
set of data blobs. Metadata can be any key/value pair. The JSON-based disk
format can be exported directly over HTTPS, mirrored and updated atomically
without race conditions, and allows for cryptographic verification of the data
back to the public signing keys of the originator.

.. A third paragraph of similar length, this time explaining what need the
   product meets.

simplestreams is used for the automatable, secure and reliable distribution of
such artifacts. For example, Ubuntu Cloud Images and their metadata are
provided using this mechanism. Where public cloud vendors integrate cloud image
distribution into their own products, Ubuntu nevertheless publishes Ubuntu
image identifiers using simplestreams, so that the same mechanism can be used
to locate Ubuntu images on any cloud.

.. Finally, a paragraph that describes whom the product is useful for.

simplestreams can be used directly by users to retrieve any subset of artifacts
and metadata, whether historical or the "latest" version. Cryptographic
verification back to the origin works through mirror layers whether full or
partial, so this also works well for internal mirrors and even air gapped
environments. Developers can use simplestreams to provide artifact and metadata
to their users that automatically carry all of these properties.

.. toctree::
   :hidden:
   :maxdepth: 2

   How-tos <how-to/index>
   Reference <reference/index>