Update mongodb plugins

* Update mongodb plugins
* fix category
* chmod +x
* flake8-CI
* flake8 adjustments for mongo_collection_ and env python3

plugins/mongodb/mongodb_docs

@@ -0,0 +1,85 @@
+#!/usr/bin/env python3
+"""
+=head1 NAME
+    MongoDB docs Plugin
+
+=head1 APPLICABLE SYSTEMS
+
+    MongoDB 3.X and 4.X with pymongo installed.
+
+=head1 CONFIGURATION
+
+    munin-node.conf
+    defauts for host is 127.0.0.1 and port 27017
+    and will work without being defined :
+
+    [mongodb_docs]
+    env.host 127.0.0.1
+    env.port 27017
+    env.username user
+    env.password P@55w0rd
+    env.db dbname
+
+    or
+
+    [mongodb_docs]
+    env.MONGO_DB_URI mongodb://user:password@host:port/dbname
+
+=head1 AUTHOR
+
+    Original script there : https://github.com/comerford/mongo-munin
+    Updated by Alban Espie-Guillon <alban.espie@alterway.fr>
+"""
+import sys
+import os
+import pymongo
+
+
+def getServerStatus():
+    if 'MONGO_DB_URI' in os.environ:
+        c = pymongo.MongoClient(os.environ['MONGO_DB_URI'])
+
+    elif 'username' and 'password' in os.environ:
+        host = os.environ.get('host', '127.0.0.1')
+        port = os.environ.get('port', 27017)
+        username = os.environ.get('username', '')
+        password = os.environ.get('password', '')
+        c = pymongo.MongoClient(host, int(port))
+        if username:
+            cAuth = c['admin']
+            cAuth.authenticate(username, password)
+
+    else:
+        c = pymongo.MongoClient()
+
+    return c.admin.command('serverStatus', workingSet=True)
+
+
+def doData():
+    ss = getServerStatus()
+    for k, v in ss["metrics"]["document"].items():
+        print(str(k) + ".value " + str(v))
+
+
+def doConfig():
+    print("""
+graph_title MongoDB documents
+graph_args --base 1000 -l 0
+graph_vlabel documents
+graph_category db
+""")
+
+    for k in getServerStatus()["metrics"]["document"]:
+        print(k + ".label " + k)
+        print(k + ".min 0")
+        print(k + ".type COUNTER")
+        print(k + ".max 500000")
+        print(k + ".draw LINE1")
+
+
+if __name__ == "__main__":
+
+    if len(sys.argv) > 1 and sys.argv[1] == "config":
+        doConfig()
+    else:
+        doData()