Merge pull request #1065 from facetoe/postgres_plugin

Postgres plugin

1 files changed, 401 insertions, 0 deletions

diff --git a/python.d/postgres.chart.py b/python.d/postgres.chart.py
new file mode 100644
index 0000000000..bb1e268cad
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+++ b/python.d/postgres.chart.py
@@ -0,0 +1,401 @@
+# -*- coding: utf-8 -*-
+# Description: example netdata python.d module
+# Authors: facetoe, dangtranhoang
+
+import re
+from copy import deepcopy
+
+import psycopg2
+from psycopg2 import extensions
+from psycopg2.extras import DictCursor
+
+from base import SimpleService
+
+# default module values
+update_every = 1
+priority = 90000
+retries = 60
+
+ARCHIVE = """
+SELECT
+    CAST(COUNT(*) AS INT) AS file_count,
+    CAST(COALESCE(SUM(CAST(archive_file ~ $r$\.ready$$r$ as INT)), 0) AS INT) AS ready_count,
+    CAST(COALESCE(SUM(CAST(archive_file ~ $r$\.done$$r$ AS INT)), 0) AS INT) AS done_count
+FROM
+    pg_catalog.pg_ls_dir('pg_xlog/archive_status') AS archive_files (archive_file);
+"""
+
+BACKENDS = """
+SELECT
+    count(*) - (SELECT count(*) FROM pg_stat_activity WHERE state = 'idle') AS backends_active,
+    (SELECT count(*) FROM pg_stat_activity WHERE state = 'idle' ) AS backends_idle
+FROM
+    pg_stat_activity;
+"""
+
+TABLE_STATS = """
+SELECT
+  ((sum(relpages) * 8) * 1024) AS size_relations,
+  count(1)                     AS relations
+FROM pg_class
+WHERE relkind IN ('r', 't');
+"""
+
+INDEX_STATS = """
+SELECT
+  ((sum(relpages) * 8) * 1024) AS size_indexes,
+  count(1)                     AS indexes
+FROM pg_class
+WHERE relkind = 'i';"""
+
+DATABASE = """
+SELECT
+  datname AS database_name,
+  sum(numbackends) AS connections,
+  sum(xact_commit) AS xact_commit,
+  sum(xact_rollback) AS xact_rollback,
+  sum(blks_read) AS blks_read,
+  sum(blks_hit) AS blks_hit,
+  sum(tup_returned) AS tup_returned,
+  sum(tup_fetched) AS tup_fetched,
+  sum(tup_inserted) AS tup_inserted,
+  sum(tup_updated) AS tup_updated,
+  sum(tup_deleted) AS tup_deleted,
+  sum(conflicts) AS conflicts
+FROM pg_stat_database
+WHERE NOT datname ~* '^template\d+'
+GROUP BY database_name;
+"""
+
+BGWRITER = 'SELECT * FROM pg_stat_bgwriter;'
+DATABASE_LOCKS = """
+SELECT
+  pg_database.datname as database_name,
+  mode,
+  count(mode) AS count
+FROM pg_locks
+  INNER JOIN pg_database ON pg_database.oid = pg_locks.database
+GROUP BY datname, mode
+ORDER BY datname, mode;
+"""
+REPLICATION = """
+SELECT
+    client_hostname,
+    client_addr,
+    state,
+    sent_offset - (
+        replay_offset - (sent_xlog - replay_xlog) * 255 * 16 ^ 6 ) AS byte_lag
+FROM (
+    SELECT
+        client_addr, client_hostname, state,
+        ('x' || lpad(split_part(sent_location,   '/', 1), 8, '0'))::bit(32)::bigint AS sent_xlog,
+        ('x' || lpad(split_part(replay_location, '/', 1), 8, '0'))::bit(32)::bigint AS replay_xlog,
+        ('x' || lpad(split_part(sent_location,   '/', 2), 8, '0'))::bit(32)::bigint AS sent_offset,
+        ('x' || lpad(split_part(replay_location, '/', 2), 8, '0'))::bit(32)::bigint AS replay_offset
+    FROM pg_stat_replication
+) AS s;
+"""
+
+LOCK_TYPES = [
+    'ExclusiveLock',
+    'RowShareLock',
+    'SIReadLock',
+    'ShareUpdateExclusiveLock',
+    'AccessExclusiveLock',
+    'AccessShareLock',
+    'ShareRowExclusiveLock',
+    'ShareLock',
+    'RowExclusiveLock'
+]
+
+ORDER = ['db_stat_transactions', 'db_stat_tuple_read', 'db_stat_tuple_returned', 'db_stat_tuple_write',
+         'backend_process', 'index_count', 'index_size', 'table_count', 'table_size', 'wal', 'background_writer']
+
+CHARTS = {
+    'db_stat_transactions': {
+        'options': [None, ' Transactions', 'Count', ' database statistics', '.db_stat_transactions', 'line'],
+        'lines': [
+            ['db_stat_xact_commit', 'Committed', 'absolute'],
+            ['db_stat_xact_rollback', 'Rolled Back', 'absolute']
+        ]},
+    'db_stat_connections': {
+        'options': [None, ' Connections', 'Count', ' database statistics', '.db_stat_connections', 'line'],
+        'lines': [
+            ['db_stat_connections', 'Connections', 'absolute']
+        ]},
+    'db_stat_tuple_read': {
+        'options': [None, ' Tuple read', 'Count', ' database statistics', '.db_stat_tuple_read', 'line'],
+        'lines': [
+            ['db_stat_blks_read', 'Disk', 'absolute'],
+            ['db_stat_blks_hit', 'Cache', 'absolute']
+        ]},
+    'db_stat_tuple_returned': {
+        'options': [None, ' Tuple returned', 'Count', ' database statistics', '.db_stat_tuple_returned', 'line'],
+        'lines': [
+            ['db_stat_tup_returned', 'Sequential', 'absolute'],
+            ['db_stat_tup_fetched', 'Bitmap', 'absolute']
+        ]},
+    'db_stat_tuple_write': {
+        'options': [None, ' Tuple write', 'Count', ' database statistics', '.db_stat_tuple_write', 'line'],
+        'lines': [
+            ['db_stat_tup_inserted', 'Inserted', 'absolute'],
+            ['db_stat_tup_updated', 'Updated', 'absolute'],
+            ['db_stat_tup_deleted', 'Deleted', 'absolute'],
+            ['db_stat_conflicts', 'Conflicts', 'absolute']
+        ]},
+    'backend_process': {
+        'options': [None, 'Backend processes', 'Count', 'Backend processes', 'postgres.backend_process', 'line'],
+        'lines': [
+            ['backend_process_active', 'Active', 'absolute'],
+            ['backend_process_idle', 'Idle', 'absolute']
+        ]},
+    'index_count': {
+        'options': [None, 'Total index', 'Count', 'Index', 'postgres.index_count', 'line'],
+        'lines': [
+            ['index_count', 'Total index', 'absolute']
+        ]},
+    'index_size': {
+        'options': [None, 'Index size', 'MB', 'Index', 'postgres.index_size', 'line'],
+        'lines': [
+            ['index_size', 'Size', 'absolute', 1, 1024 * 1024]
+        ]},
+    'table_count': {
+        'options': [None, 'Total table', 'Count', 'Table', 'postgres.table_count', 'line'],
+        'lines': [
+            ['table_count', 'Total table', 'absolute']
+        ]},
+    'table_size': {
+        'options': [None, 'Table size', 'MB', 'Table', 'postgres.table_size', 'line'],
+        'lines': [
+            ['table_size', 'Size', 'absolute', 1, 1024 * 1024]
+        ]},
+    'wal': {
+        'options': [None, 'WAL stats', 'Files', 'WAL', 'postgres.wal', 'line'],
+        'lines': [
+            ['wal_total', 'Total', 'absolute'],
+            ['wal_ready', 'Ready', 'absolute'],
+            ['wal_done', 'Done', 'absolute']
+        ]},
+    'background_writer': {
+        'options': [None, 'Checkpoints', 'Count', 'Background Writer', 'postgres.background_writer', 'line'],
+        'lines': [
+            ['background_writer_scheduled', 'Scheduled', 'absolute'],
+            ['background_writer_requested', 'Requested', 'absolute']
+        ]}
+}
+
+
+class Service(SimpleService):
+    def __init__(self, configuration=None, name=None):
+        super(self.__class__, self).__init__(configuration=configuration, name=name)
+        self.order = ORDER
+        self.definitions = CHARTS
+        self.table_stats = configuration.pop('table_stats', True)
+        self.index_stats = configuration.pop('index_stats', True)
+        self.configuration = configuration
+        self.connection = None
+        self.is_superuser = False
+        self.data = {}
+        self.old_data = {}
+        self.databases = set()
+
+    def _connect(self):
+        params = dict(user='postgres',
+                      database=None,
+                      password=None,
+                      host='localhost',
+                      port=5432)
+        params.update(self.configuration)
+
+        if not self.connection:
+            self.connection = psycopg2.connect(**params)
+            self.connection.set_isolation_level(extensions.ISOLATION_LEVEL_AUTOCOMMIT)
+            self.connection.set_session(readonly=True)
+
+    def check(self):
+        try:
+            self._connect()
+            cursor = self.connection.cursor()
+            self._discover_databases(cursor)
+            self._check_if_superuser(cursor)
+            cursor.close()
+
+            self._create_definitions()
+            return True
+        except Exception as e:
+            self.error(e)
+            return False
+
+    def _discover_databases(self, cursor):
+        cursor.execute("""
+            SELECT datname
+            FROM pg_stat_database
+            WHERE NOT datname ~* '^template\d+'
+        """)
+        self.databases = set(r[0] for r in cursor)
+
+    def _check_if_superuser(self, cursor):
+        cursor.execute("""
+            SELECT current_setting('is_superuser') = 'on' AS is_superuser;
+        """)
+        self.is_superuser = cursor.fetchone()[0]
+
+    def _create_definitions(self):
+        for database_name in self.databases:
+            for chart_template_name in list(CHARTS):
+                if chart_template_name.startswith('db_stat'):
+                    self._add_database_stat_chart(chart_template_name, database_name)
+            self._add_database_lock_chart(database_name)
+
+    def _add_database_stat_chart(self, chart_template_name, database_name):
+        chart_template = CHARTS[chart_template_name]
+        chart_name = "{}_{}".format(database_name, chart_template_name)
+        if chart_name not in self.order:
+            self.order.insert(0, chart_name)
+            name, title, units, family, context, chart_type = chart_template['options']
+            self.definitions[chart_name] = {
+                'options': [
+                    name,
+                    database_name + title,
+                    units,
+                    database_name + family,
+                    database_name + context,
+                    chart_type
+                ]
+            }
+
+            self.definitions[chart_name]['lines'] = []
+            for line in deepcopy(chart_template['lines']):
+                line[0] = "{}_{}".format(database_name, line[0])
+                self.definitions[chart_name]['lines'].append(line)
+
+    def _add_database_lock_chart(self, database_name):
+        chart_name = "{}_locks".format(database_name)
+        if chart_name not in self.order:
+            self.order.insert(0, chart_name)
+            self.definitions[chart_name] = dict(
+                options=
+                [
+                    None,
+                    database_name + ' locks',
+                    'Count',
+                    database_name + ' database statistics',
+                    database_name + '.locks',
+                    'line'
+                ],
+                lines=[]
+            )
+
+            for lock_type in LOCK_TYPES:
+                lock_id = "{}_{}".format(database_name, lock_type.lower())
+                label = re.sub("([a-z])([A-Z])", "\g<1> \g<2>", lock_type)
+                self.definitions[chart_name]['lines'].append([lock_id, label, 'absolute'])
+
+    def _get_data(self):
+        self._connect()
+
+        cursor = self.connection.cursor(cursor_factory=DictCursor)
+        self.add_stats(cursor)
+
+        cursor.close()
+        return self.data
+
+    def add_stats(self, cursor):
+        self.add_database_stats(cursor)
+        self.add_backend_stats(cursor)
+        if self.index_stats:
+            self.add_index_stats(cursor)
+        if self.table_stats:
+            self.add_table_stats(cursor)
+        self.add_lock_stats(cursor)
+        self.add_bgwriter_stats(cursor)
+
+        # self.add_replication_stats(cursor)
+
+        if self.is_superuser:
+            self.add_wal_stats(cursor)
+
+    def add_database_stats(self, cursor):
+        cursor.execute(DATABASE)
+        for row in cursor:
+            database_name = row.get('database_name')
+            self.add_derive_value('db_stat_xact_commit', prefix=database_name, value=int(row.get('xact_commit', 0)))
+            self.add_derive_value('db_stat_xact_rollback', prefix=database_name, value=int(row.get('xact_rollback', 0)))
+            self.add_derive_value('db_stat_blks_read', prefix=database_name, value=int(row.get('blks_read', 0)))
+            self.add_derive_value('db_stat_blks_hit', prefix=database_name, value=int(row.get('blks_hit', 0)))
+            self.add_derive_value('db_stat_tup_returned', prefix=database_name, value=int(row.get('tup_returned', 0)))
+            self.add_derive_value('db_stat_tup_fetched', prefix=database_name, value=int(row.get('tup_fetched', 0)))
+            self.add_derive_value('db_stat_tup_inserted', prefix=database_name, value=int(row.get('tup_inserted', 0)))
+            self.add_derive_value('db_stat_tup_updated', prefix=database_name, value=int(row.get('tup_updated', 0)))
+            self.add_derive_value('db_stat_tup_deleted', prefix=database_name, value=int(row.get('tup_deleted', 0)))
+            self.add_derive_value('db_stat_conflicts', prefix=database_name, value=int(row.get('conflicts', 0)))
+            conn_key = "{}_{}".format(database_name, 'db_stat_connections')
+            self.data[conn_key] = int(row.get('connections', 0))
+
+    def add_backend_stats(self, cursor):
+        cursor.execute(BACKENDS)
+        temp = cursor.fetchone()
+
+        self.data['backend_process_active'] = int(temp.get('backends_active', 0))
+        self.data['backend_process_idle'] = int(temp.get('backends_idle', 0))
+
+    def add_index_stats(self, cursor):
+        cursor.execute(INDEX_STATS)
+        temp = cursor.fetchone()
+        self.data['index_count'] = int(temp.get('indexes', 0))
+        self.data['index_size'] = int(temp.get('size_indexes', 0))
+
+    def add_table_stats(self, cursor):
+        cursor.execute(TABLE_STATS)
+        temp = cursor.fetchone()
+        self.data['table_count'] = int(temp.get('relations', 0))
+        self.data['table_size'] = int(temp.get('size_relations', 0))
+
+    def add_lock_stats(self, cursor):
+        cursor.execute(DATABASE_LOCKS)
+        # First zero out all current lock values.
+        for database_name in self.databases:
+            for lock_type in LOCK_TYPES:
+                lock_id = "{}_{}".format(database_name, lock_type.lower())
+                self.data[lock_id] = 0
+
+        # Now populate those that have current locks
+        for row in cursor:
+            database_name, lock_type, lock_count = row
+            lock_id = "{}_{}".format(database_name, lock_type.lower())
+            self.data[lock_id] = lock_count
+
+    def add_wal_stats(self, cursor):
+        cursor.execute(ARCHIVE)
+        temp = cursor.fetchone()
+        self.add_derive_value('wal_total', int(temp.get('file_count', 0)))
+        self.add_derive_value('wal_ready', int(temp.get('ready_count', 0)))
+        self.add_derive_value('wal_done', int(temp.get('done_count', 0)))
+
+    def add_bgwriter_stats(self, cursor):
+        cursor.execute(BGWRITER)
+        temp = cursor.fetchone()
+
+        self.add_derive_value('background_writer_scheduled', temp.get('checkpoints_timed', 0))
+        self.add_derive_value('background_writer_requested', temp.get('checkpoints_requests', 0))
+
+    def add_derive_value(self, key, value, prefix=None):
+        if prefix:
+            key = "{}_{}".format(prefix, key)
+        if key not in self.old_data.keys():
+            self.data[key] = 0
+        else:
+            self.data[key] = value - self.old_data[key]
+
+        self.old_data[key] = value
+
+
+'''
+    def add_replication_stats(self, cursor):
+        cursor.execute(REPLICATION)
+        temp = cursor.fetchall()
+        for row in temp:
+            self.add_gauge_value('Replication/%s' % row.get('client_addr', 'Unknown'),
+                                 'byte_lag',
+                                 int(row.get('byte_lag', 0)))
+'''