logger

type Caller struct {
	Package string `json:"package,omitempty"`
	File    string `json:"file,omitempty"`
	Line    string `json:"line,omitempty"`
}

type Entry struct {
	// Timestamp is the time of the entry creation.
	Timestamp time.Time `json:"timestamp,omitempty"`
	// Payload is the main message to be logged.
	Payload interface{} `json:"payload,omitempty"`
	// Labels are any key-value pairs to be logged.
	Labels map[string]string `json:"labels,omitempty"`
	// Request is any request specific info to log.
	Request *NetworkRequest `json:"request,omitempty"`
	// Caller is the location in code that concerns the log entry.
	Caller *Caller `json:"caller,omitempty"`
	// Trace can be used to group similar logs together.
	Trace string `json:"trace,omitempty"`
}

type Logger interface {
	// Debug logs at debug level.
	Debug(ctx context.Context, entry *Entry)
	// Info logs at info level.
	Info(ctx context.Context, entry *Entry)
	// Warn logs at warn level.
	Warn(ctx context.Context, entry *Entry)
	// Error logs at error level.
	Error(ctx context.Context, entry *Entry)
	// Fatal logs at fatal level.
	Fatal(ctx context.Context, entry *Entry)

	// Close flushes any buffered log entries.
	Close() error
}

type NetworkRequest struct {
	// Protocol is the request protocol.
	Protocol string `json:"type,omitempty"`
	// ID is the identifier of the request.
	ID string `json:"id,omitempty"`

	// Status is the response code of the request. Mostly used in HTTP requests.
	Status int `json:"status,omitempty"`
	// Method is the REST verb.
	Method string `json:"method,omitempty"`
	// URL is the request's URL.
	URL string `json:"url,omitempty"`

	// RequestSize is the size of the request in bytes.
	RequestSize int64 `json:"request_size,omitempty"`
	// ResponseSize is the size of the response in bytes.
	ResponseSize int64 `json:"response_size,omitempty"`
	// Latency is time taken by the server to execute the request.
	Latency time.Duration `json:"latency,omitempty"`

	// ServerIP is the IP of the server.
	ServerIP string `json:"server_ip,omitempty"`
	// ClientIP is the IP of the client.
	ClientIP string `json:"client_ip,omitempty"`
}