Feature #20864
Updated by ioquatix (Samuel Williams) 11 days ago
## Background Structured logging is a practice that organizes log data in a consistent, easily parseable format. Unlike traditional unstructured logs, which often consist of plain text entries, structured logs format information in key-value pairs or structured data formats such as JSON. This allows for better automation, searchability, and analysis of log data. In Ruby, `Kernel#warn` is extremely useful, especially because there is a mechanism for loggers to redirect warnings using the `Warning` module. However, Currently, it is difficult possible to generate structured logs with `Kernel#warn` as all include some details about the positional arguments are converted to a single string, and arbitrary keyword options are rejected. As a consequence, code like this current caller using `uplevel` for the current call stack. But it is not possible: possible to include details about exceptions. ```ruby begin ... rescue => error warn "Something went wrong!", exception: error end ``` It is very desirable Because of this, trying to have a standard interface in Ruby for emitting emit detailed structured warnings. logs from `warn` is tricky. ## Proposal I'd like to extend the current implementation propose another extension to log errors. We would allow `warn(..., **options)` to accept all options options, and forward them all to be forwarded to `Warning.warn`. This would allow us to add more details to warnings and emit structured logs using `Warning.warn`. A simple example of the proposed interface: ```ruby module Kernel def warn(*arguments, uplevel: ..., **options) # Existing processing of arguments -> message ::Warning.warn(message, **options) end end ``` Current behaviour rejects any unknown options: ``` warn("Oops", exception: error) # => <internal:warning>:50:in `warn': unknown keyword: :exception (ArgumentError) ``` I don't have an opinion about the implementation, but I wanted to get feedback on the interface.