Add prometheus metrics collection to client and server

lbry/conf.py

@@ -502,6 +502,7 @@ class Config(CLIConfig):
     )
     udp_port = Integer("UDP port for communicating on the LBRY DHT", 4444, previous_names=['dht_node_port'])
     tcp_port = Integer("TCP port to listen for incoming blob requests", 3333, previous_names=['peer_port'])
+    prometheus_port = Integer("Port to expose prometheus metrics (off by default)", 0)
     network_interface = String("Interface to use for the DHT and blob exchange", '0.0.0.0')
 
     # routing table

lbry/extras/daemon/daemon.py

@@ -17,6 +17,7 @@ from functools import wraps, partial
 import ecdsa
 import base58
 from aiohttp import web
+from prometheus_client import generate_latest as prom_generate_latest, CONTENT_TYPE_LATEST as PROM_CONTENT_TYPE_LATEST
 from google.protobuf.message import DecodeError
 from lbry.wallet import (
     Wallet, ENCRYPT_ON_DISK, SingleKey, HierarchicalDeterministic,
@@ -319,6 +320,10 @@ class Daemon(metaclass=JSONRPCServerType):
         streaming_app.router.add_get('/stream/{sd_hash}', self.handle_stream_range_request)
         self.streaming_runner = web.AppRunner(streaming_app)
 
+        prom_app = web.Application()
+        prom_app.router.add_get('/metrics', self.handle_metrics_get_request)
+        self.metrics_runner = web.AppRunner(prom_app)
+
     @property
     def dht_node(self) -> typing.Optional['Node']:
         return self.component_manager.get_component(DHT_COMPONENT)
@@ -446,6 +451,7 @@ class Daemon(metaclass=JSONRPCServerType):
         await self.analytics_manager.send_server_startup()
         await self.rpc_runner.setup()
         await self.streaming_runner.setup()
+        await self.metrics_runner.setup()
 
         try:
             rpc_site = web.TCPSite(self.rpc_runner, self.conf.api_host, self.conf.api_port, shutdown_timeout=.5)
@@ -467,6 +473,16 @@ class Daemon(metaclass=JSONRPCServerType):
             await self.analytics_manager.send_server_startup_error(str(e))
             raise SystemExit()
 
+        if self.conf.prometheus_port:
+            try:
+                metrics_site = web.TCPSite(self.metrics_runner, "0.0.0.0", self.conf.prometheus_port, shutdown_timeout=.5)
+                await metrics_site.start()
+                log.info('metrics server listening on TCP %s:%i', *metrics_site._server.sockets[0].getsockname()[:2])
+            except OSError as e:
+                log.error('metrics server failed to bind TCP :%i', self.conf.prometheus_port)
+                await self.analytics_manager.send_server_startup_error(str(e))
+                raise SystemExit()
+
         try:
             await self.initialize()
         except asyncio.CancelledError:
@@ -498,6 +514,7 @@ class Daemon(metaclass=JSONRPCServerType):
         log.info("stopped api components")
         await self.rpc_runner.cleanup()
         await self.streaming_runner.cleanup()
+        await self.metrics_runner.cleanup()
         log.info("stopped api server")
         if self.analytics_manager.is_started:
             self.analytics_manager.stop()
@@ -527,6 +544,16 @@ class Daemon(metaclass=JSONRPCServerType):
             content_type='application/json'
         )
 
+    async def handle_metrics_get_request(self, request: web.Request):
+        try:
+            return web.Response(
+                text=prom_generate_latest().decode(),
+                content_type='text/plain; version=0.0.4'
+            )
+        except Exception:
+            log.exception('could not generate prometheus data')
+            raise
+
     async def handle_stream_get_request(self, request: web.Request):
         if not self.conf.streaming_get:
             log.warning("streaming_get is disabled, rejecting request")

lbry/wallet/server/block_processor.py

@@ -749,7 +749,7 @@ class LBRYBlockProcessor(BlockProcessor):
         timer = self.timer.sub_timers['advance_blocks']
         undo = timer.run(super().advance_txs, height, txs, header, timer_name='super().advance_txs')
         timer.run(self.sql.advance_txs, height, txs, header, self.daemon.cached_height(), forward_timer=True)
-        if (height % 10000 == 0 or not self.db.first_sync) and self.logger.isEnabledFor(20):
+        if (height % 10000 == 0 or not self.db.first_sync) and self.logger.isEnabledFor(10):
             self.timer.show(height=height)
         return undo
 

lbry/wallet/server/env.py

@@ -59,6 +59,7 @@ class Env:
             self.ssl_certfile = self.required('SSL_CERTFILE')
             self.ssl_keyfile = self.required('SSL_KEYFILE')
         self.rpc_port = self.integer('RPC_PORT', 8000)
+        self.prometheus_port = self.integer('PROMETHEUS_PORT', 0)
         self.max_subscriptions = self.integer('MAX_SUBSCRIPTIONS', 10000)
         self.banner_file = self.default('BANNER_FILE', None)
         self.tor_banner_file = self.default('TOR_BANNER_FILE', self.banner_file)

lbry/wallet/server/prometheus.py

@@ -0,0 +1,36 @@
+from aiohttp import web
+from prometheus_client import Counter, generate_latest as prom_generate_latest
+from lbry.wallet.server import util
+
+NAMESPACE = "wallet_server"
+
+REQUESTS_COUNT = Counter("requests_count", "Number of requests received", namespace=NAMESPACE)
+
+
+class PrometheusServer:
+    def __init__(self):
+        self.logger = util.class_logger(__name__, self.__class__.__name__)
+        self.runner = None
+
+    async def start(self, port: int):
+        prom_app = web.Application()
+        prom_app.router.add_get('/metrics', self.handle_metrics_get_request)
+        self.runner = web.AppRunner(prom_app)
+        await self.runner.setup()
+
+        metrics_site = web.TCPSite(self.runner, "0.0.0.0", port, shutdown_timeout=.5)
+        await metrics_site.start()
+        self.logger.info('metrics server listening on %s:%i', *metrics_site._server.sockets[0].getsockname()[:2])
+
+    async def handle_metrics_get_request(self, request: web.Request):
+        try:
+            return web.Response(
+                text=prom_generate_latest().decode(),
+                content_type='text/plain; version=0.0.4'
+            )
+        except Exception:
+            self.logger.exception('could not generate prometheus data')
+            raise
+
+    async def stop(self):
+        await self.runner.cleanup()

lbry/wallet/server/server.py

@@ -2,9 +2,11 @@ import signal
 import logging
 import asyncio
 from concurrent.futures.thread import ThreadPoolExecutor
+import typing
 
 import lbry
 from lbry.wallet.server.mempool import MemPool, MemPoolAPI
+from lbry.wallet.server.prometheus import PrometheusServer
 
 
 class Notifications:
@@ -74,6 +76,7 @@ class Server:
         self.daemon = daemon = env.coin.DAEMON(env.coin, env.daemon_url)
         self.db = db = env.coin.DB(env)
         self.bp = bp = env.coin.BLOCK_PROCESSOR(env, db, daemon, notifications)
+        self.prometheus_server: typing.Optional[PrometheusServer] = None
 
         # Set notifications up to implement the MemPoolAPI
         notifications.height = daemon.height
@@ -107,11 +110,15 @@ class Server:
         await self.db.populate_header_merkle_cache()
         await _start_cancellable(self.mempool.keep_synchronized)
         await _start_cancellable(self.session_mgr.serve, self.notifications)
+        await _start_cancellable(self.start_prometheus)
 
     async def stop(self):
         for task in reversed(self.cancellable_tasks):
             task.cancel()
         await asyncio.wait(self.cancellable_tasks)
+        if self.prometheus_server:
+            await self.prometheus_server.stop()
+            self.prometheus_server = None
         self.shutdown_event.set()
         await self.daemon.close()
 
@@ -132,3 +139,8 @@ class Server:
         finally:
             loop.run_until_complete(self.stop())
             executor.shutdown(True)
+
+    async def start_prometheus(self, event):
+        if not self.prometheus_server and self.env.prometheus_port:
+            self.prometheus_server = PrometheusServer()
+            await self.prometheus_server.start(self.env.prometheus_port)

lbry/wallet/server/session.py

@@ -27,6 +27,7 @@ from lbry.wallet.server.db.writer import LBRYDB
 from lbry.wallet.server.db import reader
 from lbry.wallet.server.websocket import AdminWebSocket
 from lbry.wallet.server.metrics import ServerLoadData, APICallMetrics
+from lbry.wallet.server.prometheus import REQUESTS_COUNT
 
 from lbry.wallet.rpc import (
     RPCSession, JSONRPCAutoDetect, JSONRPCConnection,
@@ -709,6 +710,7 @@ class SessionBase(RPCSession):
         """Handle an incoming request.  ElectrumX doesn't receive
         notifications from client sessions.
         """
+        REQUESTS_COUNT.inc()
         if isinstance(request, Request):
             handler = self.request_handlers.get(request.method)
         else:

setup.py

@@ -44,6 +44,7 @@ setup(
         'cryptography==2.5',
         'protobuf==3.6.1',
         'msgpack==0.6.1',
+        'prometheus_client==0.7.1',
         'ecdsa==0.13.3',
         'pyyaml==4.2b1',
         'docopt==0.6.2',