fix: Hide other sensitive cfg values

[epociask]

Fixes Issue

Fixes #176

Changes proposed

Screenshots (Optional)

Note to reviewers

[samlaf]

Thanks for this! Just one thing to fix

[samlaf]

Why did you move this after the marshaling? Like this it doesn’t do anything

[epociask]

it does actually - the SignerPrivateKey is stored as part of the EigenDAClientConfig which is defined within layr-labs/eigenda

[samlaf]

The log line below is

log.Info(fmt.Sprintf("Initializing EigenDA proxy server with config: %v", string(configJSON)))

which prints the already marshalled config. So changing the fields of cfg here above doesn't do anything.

[epociask]

🤦‍♂️

[samlaf]

Thought about this approach some more and not sure I like it, for a few reasons:

1. if some future developer ever wants to marshal AND unmarshal the config for whatever reason he will run into a bug (can fix this by defining a custom marshalJSONHideSecrets function instead)
2. this will print empty string, so reader won’t know if password field was hidden or just never set (we can fix this by using omitempty json tag)

Could look something like this (Claude generated so beware):

package main

import (
	"encoding/json"
	"fmt"
	"time"
)

type Config struct {
	Endpoint string        `json:"endpoint"`
	Password string        `json:"password,omitempty"`
	DB       int           `json:"database"`
	Eviction time.Duration `json:"eviction"`
}

// Custom MarshalJSON function to control what gets included in the JSON output
func (c Config) MarshalJSON() ([]byte, error) {
	type Alias Config // Use an alias to avoid recursion with MarshalJSON
	aux := struct {
		Alias
		Password string `json:"password,omitempty"`
	}{
		Alias:    (Alias)(c),
		Password: "",
	}

	// Conditionally include a masked password if it is set
	if c.Password != "" {
		aux.Password = "****" // Mask the password instead of excluding it
	}
	return json.Marshal(aux)
}

func main() {
	cfg := Config{
		Endpoint: "localhost:6379",
		Password: "supersecret",
		DB:       0,
		Eviction: time.Hour,
	}

	jsonData, _ := json.MarshalIndent(cfg, "", "  ")
	fmt.Println(string(jsonData))
}

Maybe also use a separate Marshal function to not change the default marshaling behavior?