py-grpc-prometheus 0.2.0

Python gRPC Prometheus Interceptors

py-grpc-prometheus

Instrument library to provide prometheus metrics similar to:

• https://github.com/grpc-ecosystem/java-grpc-prometheus
• https://github.com/grpc-ecosystem/go-grpc-prometheus

Status

Currently, the library has the parity metrics with the Java and Go library.

Server side:

• grpc_server_started_total
• grpc_server_handled_total
• grpc_server_handled_latency_seconds
• grpc_server_msg_received_total
• grpc_server_msg_sent_total

Client side:

• grpc_client_started_total
• grpc_client_completed
• grpc_client_completed_latency_seconds
• grpc_client_msg_sent_total
• grpc_client_msg_received_total

How to use

pip install py-grpc-prometheus

Client side:

Client metrics monitoring is done by intercepting the gPRC channel.

import grpc
from py_grpc_prometheus.prometheus_client_interceptor import PromClientInterceptor

channel = grpc.intercept_channel(grpc.insecure_channel('server:6565'),
                                         PromClientInterceptor())  
# Start an end point to expose metrics.
start_http_server(metrics_port)

Server side:

Server metrics are exposed by adding the interceptor when the gRPC server is started. Take a look at tests/integration/hello_world/hello_world_client.py for the complete example.

import grpc
from concurrent import futures
from py_grpc_prometheus.prometheus_server_interceptor import PromServerInterceptor
from prometheus_client import start_http_server

Start the gRPC server with the interceptor, take a look at tests/integration/hello_world/hello_world_server.py for the complete example.

server = grpc.server(futures.ThreadPoolExecutor(max_workers=10),
                         interceptors=(PromServerInterceptor(),))
# Start an end point to expose metrics.
start_http_server(metrics_port)

How to run and test

1. Run the testing server

python -m tests.integration.hello_world.hello_world_sever

2. Run the testing client

python -m tests.integration.hello_world.hello_world_client

3. Open http://localhost:50052 for the server side metrics
4. Open http://localhost:50053 for the client side metrics

TODO:

• Unit test with https://github.com/census-instrumentation/opencensus-python/blob/master/tests/unit/trace/ext/grpc/test_server_interceptor.py

Reference

• https://grpc.io/grpc/python/grpc.html
• https://github.com/census-instrumentation/opencensus-python/blob/master/opencensus/trace/ext/grpc/utils.py
• https://github.com/opentracing-contrib/python-grpc/blob/b4bdc7ce81fa75ede00f7c6bcf5dab8fae47332a/grpc_opentracing/grpcext/grpc_interceptor/server_interceptor.py