cmd, dashboard, log: log collection and exploration (#17097)

* cmd, dashboard, internal, log, node: logging feature

* cmd, dashboard, internal, log: requested changes

* dashboard, vendor: gofmt, govendor, use vendored file watcher

* dashboard, log: gofmt -s -w, goimports

* dashboard, log: gosimple

log/format.go

@@ -77,11 +77,11 @@ type TerminalStringer interface {
 // a terminal with color-coded level output and terser human friendly timestamp.
 // This format should only be used for interactive programs or while developing.
 //
-//     [TIME] [LEVEL] MESAGE key=value key=value ...
+//     [LEVEL] [TIME] MESAGE key=value key=value ...
 //
 // Example:
 //
-//     [May 16 20:58:45] [DBUG] remove route ns=haproxy addr=127.0.0.1:50002
+//     [DBUG] [May 16 20:58:45] remove route ns=haproxy addr=127.0.0.1:50002
 //
 func TerminalFormat(usecolor bool) Format {
 	return FormatFunc(func(r *Record) []byte {
@@ -202,6 +202,48 @@ func JSONFormat() Format {
 	return JSONFormatEx(false, true)
 }
 
+// JSONFormatOrderedEx formats log records as JSON arrays. If pretty is true,
+// records will be pretty-printed. If lineSeparated is true, records
+// will be logged with a new line between each record.
+func JSONFormatOrderedEx(pretty, lineSeparated bool) Format {
+	jsonMarshal := json.Marshal
+	if pretty {
+		jsonMarshal = func(v interface{}) ([]byte, error) {
+			return json.MarshalIndent(v, "", "    ")
+		}
+	}
+	return FormatFunc(func(r *Record) []byte {
+		props := make(map[string]interface{})
+
+		props[r.KeyNames.Time] = r.Time
+		props[r.KeyNames.Lvl] = r.Lvl.String()
+		props[r.KeyNames.Msg] = r.Msg
+
+		ctx := make([]string, len(r.Ctx))
+		for i := 0; i < len(r.Ctx); i += 2 {
+			k, ok := r.Ctx[i].(string)
+			if !ok {
+				props[errorKey] = fmt.Sprintf("%+v is not a string key,", r.Ctx[i])
+			}
+			ctx[i] = k
+			ctx[i+1] = formatLogfmtValue(r.Ctx[i+1], true)
+		}
+		props[r.KeyNames.Ctx] = ctx
+
+		b, err := jsonMarshal(props)
+		if err != nil {
+			b, _ = jsonMarshal(map[string]string{
+				errorKey: err.Error(),
+			})
+			return b
+		}
+		if lineSeparated {
+			b = append(b, '\n')
+		}
+		return b
+	})
+}
+
 // JSONFormatEx formats log records as JSON objects. If pretty is true,
 // records will be pretty-printed. If lineSeparated is true, records
 // will be logged with a new line between each record.