The router taps function service one by one which is inefficient and
increases the burden of executor. This PR aggregates all requests into
one to solve the problem mentioned above.
If the context of request is closed before ReverseProxy finishing writing
a huge response body to the response writer, the client will only receive
a truncated response body.
To solve this, move the context cancel after ReverseProxy finished.
1. The records are stored in redis which is not migratable to another cluster for the testing purposes.
2. Some of the requests fields are not recorded.
3. People should consider using https://github.com/buger/goreplay which is an existing mature and well-tested solution for testing purposes.
The router prints error no matter what error type it is.
It's useful for troubleshooting, however, it also prints
the context canceled error, which means that users abort
request before reply and its really normal nowadays. Also,
the router returns 502 if error is not nil and may confused
client if it's a timeout error.
To solve these problems, this PR adds an error handler to
reverse proxy to examine the return error and change the
status code when needed.
This PR removes not so useful logs and changes most of Info level
log to Debug/Error level in hot path while preserving some of them
that is helpful for troubleshooting.
