Request that Elasticsearch cat shards and cat indices show closed indices as CLOSED instead of STARTED

[mark54g]

This request is to have Elasticsearch, in response to v7.2's change in behavior per: #33888 - show closed indices as CLOSED rather than STARTED, plus, a way to get a quick count back of all shards/indices in all states.

Something along the lines of:

.watcher-history-10-2020.09.02  0     p      STARTED     11520  13.9mb 127.0.0.1 mv7-1
.watcher-history-10-2020.09.01  0     p      STARTED     11520  13.9mb 127.0.0.1 mv7-1
.watches                        0     p      STARTED         6 129.1mb 127.0.0.1 mv7-1
.monitoring-es-7-2020.09.07     0     p      STARTED    268263 285.3mb 127.0.0.1 mv7-1
.kibana_1                       0     p      STARTED        73 202.4kb 127.0.0.1 mv7-1
.watcher-history-10-2020.09.06  0     p      STARTED     11520  12.5mb 127.0.0.1 mv7-1
.monitoring-es-7-2020.09.04     0     p      STARTED    329063 171.1mb 127.0.0.1 mv7-1
.kibana_task_manager            0     p      STARTED         2  30.9kb 127.0.0.1 mv7-1
.monitoring-kibana-7-2020.09.02 0     p      STARTED      8636   2.9mb 127.0.0.1 mv7-1
test1                           0     p      CLOSED         4   3.5kb 127.0.0.1 mv7-1

with, perhaps a way to hit _cat/shards?c (which doesn't exist, yet) to show a list of:

STARTED          across $NODES: 21
UNASSIGNED       across $NODES: 1
CLOSED           across $NODES: 1

etc

A way to also differentiate when doing a _cat/allocation as well, would help to quickly get to the root of issues faster

[elasticmachine]

Pinging @elastic/es-core-features (:Core/Features/Indices APIs)

[sastorsl]

I agree that it would be handy to get a summary / count from the API.

Allthough it is quite easy to get that with a script.

/_cat/shards?h=state | sort | uniq -c

Or the more elaborate:

/_cat/shards?h=state | awk '{ arr[$1]++ } END { for (i in arr) printf("%-20s across $nodes: %6i\n", i, arr[i]) | "sort" }'
RELOCATING           across $nodes:      2
STARTED              across $nodes:   6924

However, I would also like to be able to see if an index is closed by looking directly at the shards, and I haven't been able to discover any safe method. One can look at if docs is null, but that isn't really safe.