LoggerBackends - SQL Logger backends functionality for Elixir v1.15+

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1

Hi, I’ve created an SQL logger backend using LoggerBackends: GitHub - vkryukov/logger_backends_sql.

It safely stores all metadata and can be configured to use an existing Repo and/or Schema.

The simplest setup uses an SQLite3 database for logs:

# config/config.exs
config :logger, LoggerBackends.SQL,
  level: :debug,
  path: "./logs.sqlite"

Logs will be written to the logs table. You can also use an existing repo and customize the table name:

# config/config.exs
config :logger, LoggerBackends.SQL,
   repo: MyApp.Repo,
   table_name: "log_messages"

You can use your own Schema for log messages - just ensure the schema module defines a changeset/1 function that accepts time, message, and meta arguments.

Feedback welcome!

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2

While we are here, I would like people’s thoughts on the best way to configure the backend during the runtime.

LoggerBackends offers configure/2, which can be called like this:

LoggerBackends.configure(LoggerBackends.SQL,
   option1: value1,
   option2: value2,
   ...
)

and will send a :configure event to the backend that it can capture. The reference implementation for LoggerBackend.Console is here. This call will only succeed after a backend has already been added with LoggerBackend.add(LoggerBackends.SQL) (as someone needs to listen to these events).

However, you definitely want to set the path to a SQLite log database before adding the backend to perform all the initialization in the backend’s init function.

Something like this would be nice

LoggerBackends.add(LoggerBackends.SQL,
   path: "./my.sqlite", 
   repo: nil
)

However, LoggerBackends.add/2 only processes the :flush option and ignores everything else.

So my current solution is to expose my own configure/1 to do the runtime config:

LoggerBackends.SQL.configure(
  path: "./test1.sqlite",
  repo: nil
)
LoggerBackends.add(LoggerBackends.SQL)

The previous option with LoggerBackend.add/2 is IMHO cleaner, but requires changing the existing contract.

Thoughts?