How to use ellipsis for zap global logger

Question

Hello I am trying to change sugar logger to global longer I checked possible fields which I can use but I couldn't something solve my problem

for example in some situations I use

                    zap.L().Debug("recv_cmd",
                        zap.String("user", c.GetString("user")),
                        zap.String("path", c.Request.URL.Path),
                    )

This is what I use in most of the cases but I have one different case which like this

    params := make([]interface{}, 0, 20)
    params = append(params,
        "status", c.Writer.Status(),
        "method", c.Request.Method
        "path", c.Request.URL.Path,
        "ip", c.ClientIP(),
    )
    if len(body) > 0 {
        params = append(params, "body", string(body))
    }

so in this case, I don't have a body in every request, so params obj doesn't have the same struck for each request

what I want is (this is just a simple demonstration I know stringer won't work)

    zap.L().Info("Info",
        zap.Stringer("request", params...),
    )

score 0 · Accepted Answer · answered Dec 12 '21 at 03:40

The definition of Logger.Info is:

func (log *Logger) Info(msg string, fields ...Field)

and the definition of zap.Stringer is:

func Stringer(key string, val fmt.Stringer) Field

So there are a number of issues with what you are attempting:

You cannot pass []interface{} to a function that accepts fmt.Stringer (because it does not implement the interface).
zap.Stringer returns a single Field whereas you are really trying to log multiple fields.

What I think you are trying to accomplish is (playground) (but I'm not really clear whether params is being created specifically for logging or for another reason):

var params []zap.Field
params = append(params,
    zap.String("status", c.Status),
    zap.String("method", c.Method),
    zap.String("path", c.URL.Path),
    zap.String("ip", c.ClientIP),
)
if len(body) > 0 {
    params = append(params, zap.String("body", string(body)))
}
zap.L().Info("Info", params...)

If that does not do what you are doing take a look at the variety of encoders that zap provides (e.g. Any, Inline etc).

Note: I have simplified your structure somewhat (because you did not include details). It is easier to answer questions like this if you include a minimum reproducible example (i.e. you should define structures used but only to the degree needed to illustrate the issue).

How to use ellipsis for zap global logger

1 Answers1