Add storage stats to collection metrics

[masaruhoshi]

Includes additional information about collection stats about "storage".

# HELP mongodb_mydb_mycol_storageStats_avgObjSize mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_avgObjSize untyped
mongodb_mydb_mycol_storageStats_avgObjSize{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 238
# HELP mongodb_mydb_mycol_storageStats_capped mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_capped untyped
mongodb_mydb_mycol_storageStats_capped{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 0
# HELP mongodb_mydb_mycol_storageStats_count mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_count untyped
mongodb_mydb_mycol_storageStats_count{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 57
# HELP mongodb_mydb_mycol_storageStats_freeStorageSize mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_freeStorageSize untyped
mongodb_mydb_mycol_storageStats_freeStorageSize{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 0
# HELP mongodb_mydb_mycol_storageStats_indexSizes_id mydb.mycol.storageStats.indexSizes.
# TYPE mongodb_mydb_mycol_storageStats_indexSizes_id untyped
mongodb_mydb_mycol_storageStats_indexSizes_id{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 20480
# HELP mongodb_mydb_mycol_storageStats_nindexes mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_nindexes untyped
mongodb_mydb_mycol_storageStats_nindexes{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 1
# HELP mongodb_mydb_mycol_storageStats_scaleFactor mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_scaleFactor untyped
mongodb_mydb_mycol_storageStats_scaleFactor{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 1
# HELP mongodb_mydb_mycol_storageStats_size mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_size untyped
mongodb_mydb_mycol_storageStats_size{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 13591
# HELP mongodb_mydb_mycol_storageStats_storageSize mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_storageSize untyped
mongodb_mydb_mycol_storageStats_storageSize{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 20480
# HELP mongodb_mydb_mycol_storageStats_totalIndexSize mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_totalIndexSize untyped
mongodb_mydb_mycol_storageStats_totalIndexSize{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 20480
# HELP mongodb_mydb_mycol_storageStats_totalSize mydb.mycol.storageStats.
# TYPE mongodb_mydb_mycol_storageStats_totalSize untyped
mongodb_mydb_mycol_storageStats_totalSize{cl_id="5f107dfb3a6fc97a81753480",cl_role="shardsvr",collection="mycol",database="mydb",rs_nm="shard-0",rs_state="1"} 40960

This is intentionally filtering out any information from storageStats.wiredTiger and storageStats.indexDetails since it can lead to a high-cardinality issues

db.mycol.aggregate( [ { $collStats: { storageStats: { scale: 1 } } }, { "$project": { "storageStats.wiredTiger": 0, "storageStats.indexDetails": 0 } } ] ).pretty()
{
        "ns" : "mydb.mycol",
        "host" : "localhost:27017",
        "localTime" : ISODate("2021-06-02T02:02:59.173Z"),
        "storageStats" : {
                "size" : 7391055,
                "count" : 48265,
                "avgObjSize" : 153,
                "storageSize" : 4222976,
                "freeStorageSize" : 548864,
                "capped" : false,
                "nindexes" : 3,
                "indexBuilds" : [ ],
                "totalIndexSize" : 5398528,
                "totalSize" : 9621504,
                "indexSizes" : {
                        "_id_" : 2646016,
                        "key_1" : 2183168,
                        "licenseKey_1" : 569344
                },
                "scaleFactor" : 1
        }
}

---

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• Fix conflicts with target branch.
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[askomorokhov]

Thanks for contributions.
Looks good to me. 👍

[percona-csalguero]

Ran the tests manually and all are passing.
Also I see the metrics:

# HELP mongodb_test_c1_localTime test.c1.
# TYPE mongodb_test_c1_localTime untyped
mongodb_test_c1_localTime{cl_id="60b8cc6dc871fe9be7729427",cl_role="shardsvr",collection="c1",database="test",rs_nm="rs1",rs_state="1"} 1.622725322282e+12
# HELP mongodb_test_c1_storageStats_avgObjSize test.c1.storageStats.
# TYPE mongodb_test_c1_storageStats_avgObjSize untyped
mongodb_test_c1_storageStats_avgObjSize{cl_id="60b8cc6dc871fe9be7729427",cl_role="shardsvr",collection="c1",database="test",rs_nm="rs1",rs_state="1"} 34
# HELP mongodb_test_c1_storageStats_capped test.c1.storageStats.
# TYPE mongodb_test_c1_storageStats_capped untyped
mongodb_test_c1_storageStats_capped{cl_id="60b8cc6dc871fe9be7729427",cl_role="shardsvr",collection="c1",database="test",rs_nm="rs1",rs_state="1"} 0

Thanks for the contribution

[percona-csalguero]

Hi @masaruhoshi,
I've created #287
Thanks for the help.

[Aleksa-del]

@masaruhoshi Hello! We would love to send you a gift from Percona for your contributions. Please, contact us at [email protected]