[Metricbeat] add more metric collection into pubsub metricset (elasti…

…c#17600) (elastic#17652)

* add more metric collection into pubsub metricset
* fix docs.asciidoc for pubsub

(cherry picked from commit 63e38d1)

CHANGELOG.next.asciidoc

@@ -194,6 +194,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - Fix vsphere VM dashboard host aggregation visualizations. {pull}17555[17555]
 - Fix azure storage dashboards. {pull}17590[17590]
 - Metricbeat no longer needs to be started strictly after Logstash for `logstash-xpack` module to report correct data. {issue}17261[17261] {pull}17497[17497]
+- Fix pubsub metricset to collect all GA stage metrics from gcp stackdriver. {issue}17154[17154] {pull}17600[17600]
 - Add privileged option so as mb to access data dir in Openshift. {pull}17606[17606]
 - Fix "ID" event generator of Google Cloud module {issue}17160[17160] {pull}17608[17608]
 - Fix storage metricset to allow config without region/zone. {issue}17623[17623] {pull}17624[17624]

x-pack/metricbeat/module/googlecloud/pubsub/_meta/data.json

@@ -14,14 +14,34 @@
     "googlecloud": {
         "labels": {
             "resource": {
-                "topic_id": "test-ks"
+                "subscription_id": "test-ks"
             }
         },
         "pubsub": {
+            "snapshot": {
+                "backlog_bytes": 19,
+                "backlog_bytes_by_region": 19,
+                "num_messages": 4,
+                "num_messages_by_region": 4,
+                "oldest_message_age": 69319,
+                "oldest_message_age_by_region": 69319
+            },
             "subscription": {
-                "backlog_bytes": 20,
-                "num_undelivered_messages": 4,
-                "oldest_unacked_message_age": 435752
+                "backlog_bytes": 0,
+                "num_undelivered_messages": 0,
+                "oldest_retained_acked_message_age": 0,
+                "oldest_retained_acked_message_age_by_region": 0,
+                "oldest_unacked_message_age": 0,
+                "oldest_unacked_message_age_by_region": 69277,
+                "retained_acked_bytes": 0,
+                "retained_acked_bytes_by_region": 0,
+                "unacked_bytes_by_region": 19
+            },
+            "topic": {
+                "oldest_retained_acked_message_age_by_region": 0,
+                "oldest_unacked_message_age_by_region": 69319,
+                "retained_acked_bytes_by_region": 0,
+                "unacked_bytes_by_region": 76
             }
         }
     },