John Spray 4892a5c5b7 pageserver: avoid logging the "ERROR" part of DbErrors that are successes (#4902) ...

## Problem

The pageserver<->safekeeper protocol uses error messages to indicate end
of stream. pageserver already logs these at INFO level, but the inner
error message includes the word "ERROR", which interferes with log
searching.
   
Example:
```
  walreceiver connection handling ended: db error: ERROR: ending streaming to Some("pageserver") at 0/4031CA8
```
    
The inner DbError has a severity of ERROR so DbError's Display
implementation includes that ERROR, even though we are actually
logging the error at INFO level.

## Summary of changes

Introduce an explicit WalReceiverError type, and in its From<>
for postgres errors, apply the logic from ExpectedError, for
expected errors, and a new condition for successes.
    
The new output looks like:
```
    walreceiver connection handling ended: Successful completion: ending streaming to Some("pageserver") at 0/154E9C0, receiver is caughtup and there is no computes
 ```

2023-08-08 12:35:24 +03:00

..

spec

Fix typos

2022-05-28 14:02:05 +03:00

src

pageserver: avoid logging the "ERROR" part of DbErrors that are successes (#4902)

2023-08-08 12:35:24 +03:00

Cargo.toml

Add more safekeeper and walreceiver metrics (#4142)

2023-05-03 17:07:41 +03:00