gRPC-Logger

This is a simple Express Middleware for remote request logging using gRPC

Server

The repository contains the code for the logging server writting in Golang. Run the server.go file to start the logging server. All new logs will be written to a requests_log.ndjson file on the server. Currently the gRPC server only has a LogRequest method that takes a message of type Log as input and returns a type Response which will always be an empty {} The Log type requires an object with key body and value of any string which will be logged. To change the input or response structure, modify logger.proto in the server and in the Express Middleware as needed.

After modifying the logger.proto, run

protoc --go_out=plugins=grpc:logger ./logger.proto

This will regenerate the gRPC code for the server connections.

To modify the LogRequest functionality, edit the LogRequestfunction in logger/logger.go Currently it just accepts the input in, calls a function to write in.Body to logfile, and sends the response.

Express Middleware

The gRPC server can be called from any client to log any data. However, this repository contains the code to make requests from a NodeJS client.

The express-middleware folder contains the middleware and proto file for logging. Check the example folder on how to use it. Make sure to include the sacme proto file as that on the server.

By default, the middleware connects to localhost:9000 as gRPC server location. Change as necessary.

For each incoming request, the middleware makes a remote call to the logger with the following details from the request -

• Time of request
• Remote Address from connection header, or proxy header if the server is behind a reverse proxy
• HTTP method
• URL
• HTTP Version
• Headers

These are completely customizable and you can add or remove any data you want to change The selected ones are the fields in the Morgan logger "common" predefined format