setBindings is no longer available on the typing of FastifyBaseLogger

[silenceisgolden]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the regression has not already been reported

Last working version

4.3.0

Stopped working in version

4.8.1

Node.js version

18.x

Operating system

Linux

Operating system version (i.e. 20.04, 11.3, 10)

20.04

💥 Regression Report

FastifyLoggerInstance had a method called setBindings that I am using currently to preserve context across multiple log method calls. It looks like FastifyLoggerInstance was replaced with FastifyBaseLogger in #4224, but the typings (at least) show the method as missing when my typecheck runs in my CI checks:

// tsc --noEmit

> tsc --noEmit

src/_framework/context-from-params.ts:41:14 - error TS2339: Property 'setBindings' does not exist on type 'FastifyBaseLogger'.

41    state.log.setBindings(metadata);
                ~~~~~~~~~~~

src/_framework/context-from-request.ts:31:[16](<redacted>/actions/runs/3227392130/jobs/5282140045#step:5:17) - error TS2339: Property 'setBindings' does not exist on type 'FastifyBaseLogger'.

31    request.log.setBindings(metadata);
                  ~~~~~~~~~~~


Found 2 errors in 2 files.

Steps to Reproduce

Sorry that I cannot link to the project, but I think if you have a default simple fastify project that calls request.log.setBindings() in 4.3 and upgrade it to 4.8, the type checking should fail with a similar error as above.

Expected Behavior

I would expect that this method would be preserved in source code and types unless there was a major version change.

[silenceisgolden]

👏🏻 to @BlackHole1, @climba03003 and @mcollina. Thanks for addressing this so quickly.

[BlackHole1]

@silenceisgolden Sorry, we had to revert because this change triggered #4354. until we can think of a better way, you can use the following solution.

In fastify.d.ts file

declare module "fastify" {
    interface FastifyBaseLogger {
        setBindings(bindings: import("pino").Bindings): void;
    }
}

In tsconfig.json file

{
  "....": "...",
  "include": ["fastify.d.ts"]
}

[tzafrirben]

@mcollina Will this approach even work? FastifyBaseLogger is a type alias and not an interface

declare module "fastify" {
    interface FastifyBaseLogger {
        setBindings(bindings: import("pino").Bindings): void;
    }
}

I guess that my real question is why is FastifyBaseLogger not an interface so users can take advantage of declaration merging and extract them

[mcollina]

I don't know, would you like to try a fix in a PR?

[tzafrir-benami-sage]

Agreed - I will try to create a commit according to contribution guide lines.