Revert "Remove installation via snap package (#4826)" (#4937)

This reverts commit e9d703c.

src/docs/src/install/index.rst

@@ -24,6 +24,7 @@ Installation
     mac
     freebsd
     docker
+    snap
     kubernetes
     search
     nouveau

src/docs/src/install/snap.rst

@@ -0,0 +1,47 @@
+.. Licensed under the Apache License, Version 2.0 (the "License"); you may not
+.. use this file except in compliance with the License. You may obtain a copy of
+.. the License at
+..
+..   http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+.. WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+.. License for the specific language governing permissions and limitations under
+.. the License.
+
+.. _install/snap:
+
+=====================
+Installation via Snap
+=====================
+
+.. highlight:: sh
+
+Apache CouchDB provides 'convenience binary' Snap builds through the
+Ubuntu snapcraft repository under the name ``couchdb``. Only snaps built
+from official stable CouchDB releases (``2.0``, ``2.1``, etc.) are available
+through this channel. There are separate snap channels for each major
+release stream, e.g. ``2.x``, ``3.x``, as well as a ``latest`` stream.
+
+After `installing snapd`_, the CouchDB snap can be installed via::
+
+    $ sudo snap install couchdb
+
+CouchDB will be installed at ``/snap/couchdb``. Data will be stored at
+``/var/snap/couchdb/``.
+
+Please note that all other file system paths are **relative to the snap
+`chroot`** instead of the system root. In addition, the exact path
+depends on your system. For example, when you normally want to
+reference `/opt/couchdb/etc/local.ini`, under snap, this could live at
+`/snap/couchdb/5/opt/couchdb/etc/local.ini`.
+
+**Your installation is not complete. Be sure to complete the**
+:ref:`Setup <setup>` **steps for a single node or clustered installation.**
+
+Further details on the snap build process are available in our
+`couchdb-pkg git repository`_.
+
+.. _installing snapd: https://snapcraft.io/docs/core/install
+.. _couchdb-pkg git repository: https://github.com/apache/couchdb-pkg