add support for filtering by network ID

This adds support for filtering by network ID, to be
consistent with other filter options.

Note that only *full* matches are returned; this is
consistent with other filters (e.g. volume), that
also return full matches only.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

docs/reference/commandline/ps.md

@@ -62,7 +62,7 @@ The currently supported filters are:
 * since (container's id or name) - filters containers created since given id or name
 * isolation (default|process|hyperv)   (Windows daemon only)
 * volume (volume name or mount point) - filters containers that mount volumes.
-* network (network name) - filters containers connected to the provided network name
+* network (network id or name) - filters containers connected to the provided network
 
 #### Label
 
@@ -209,15 +209,33 @@ The `volume` filter shows only containers that mount a specific volume or have a
 
 #### Network
 
-The `network` filter shows only containers that has endpoints on the provided network name.
+The `network` filter shows only containers that are connected to a network with
+a given name or id.
 
+The following filter matches all containers that are connected to a network
+with a name containing `net1`.
+
+```bash
 $ docker run -d --net=net1 --name=test1 ubuntu top
 $ docker run -d --net=net2 --name=test2 ubuntu top
 
 $ docker ps --filter network=net1
 CONTAINER ID        IMAGE       COMMAND       CREATED             STATUS              PORTS               NAMES
 9d4893ed80fe        ubuntu      "top"         10 minutes ago      Up 10 minutes                           test1
+```
 
+The network filter matches on both the network's name and id. The following
+example shows all containers that are attached to the `net1` network, using
+the network id as a filter;
+
+```bash
+$ docker network inspect --format "{{.ID}}" net1
+8c0b4110ae930dbe26b258de9bc34a03f98056ed6f27f991d32919bfe401d7c5
+
+$ docker ps --filter network=8c0b4110ae930dbe26b258de9bc34a03f98056ed6f27f991d32919bfe401d7c5
+CONTAINER ID        IMAGE       COMMAND       CREATED             STATUS              PORTS               NAMES
+9d4893ed80fe        ubuntu      "top"         10 minutes ago      Up 10 minutes                           test1
+```
 
 ## Formatting
 

man/docker-ps.1.md

@@ -36,7 +36,7 @@ the running containers.
    - since=(<container-name>|<container-id>)
    - ancestor=(<image-name>[:tag]|<image-id>|<image@digest>) - containers created from an image or a descendant.
    - volume=(<volume-name>|<mount-point-destination>)
-   - network=(<network-name>) - containers connected to the provided network name
+   - network=(<network-name>|<network-id>) - containers connected to the provided network
 
 **--format**="*TEMPLATE*"
    Pretty-print containers using a Go template.