improve bubble up errors and fix a few logging messages

pkg/acquisition/modules/loki/loki.go

@@ -82,11 +82,11 @@ func (l *LokiSource) GetAggregMetrics() []prometheus.Collector {
 func (l *LokiSource) UnmarshalConfig(yamlConfig []byte) error {
 	err := yaml.UnmarshalStrict(yamlConfig, &l.Config)
 	if err != nil {
-		return errors.Wrap(err, "Cannot parse LokiAcquisition configuration")
+		return fmt.Errorf("cannot parse loki acquisition configuration: %w", err)
 	}
 
 	if l.Config.Query == "" {
-		return errors.New("Loki query is mandatory")
+		return errors.New("loki query is mandatory")
 	}
 
 	if l.Config.WaitForReady == 0 {
@@ -141,8 +141,7 @@ func (l *LokiSource) Configure(config []byte, logger *log.Entry) error {
 	}
 
 	l.Client = lokiclient.NewLokiClient(clientConfig)
-	l.Client.Logger = logger.WithField("component", "lokiclient")
-	l.Client.Logger.WithField("source", l.Config.URL)
+	l.Client.Logger = logger.WithFields(log.Fields{"component": "lokiclient", "source": l.Config.URL})
 	return nil
 }
 
@@ -155,13 +154,13 @@ func (l *LokiSource) ConfigureByDSN(dsn string, labels map[string]string, logger
 
 	u, err := url.Parse(dsn)
 	if err != nil {
-		return errors.Wrap(err, "can't parse dsn configuration : "+dsn)
+		return fmt.Errorf("while parsing dsn '%s': %w", dsn, err)
 	}
 	if u.Scheme != "loki" {
 		return fmt.Errorf("invalid DSN %s for loki source, must start with loki://", dsn)
 	}
 	if u.Host == "" {
-		return errors.New("Empty loki host")
+		return errors.New("empty loki host")
 	}
 	scheme := "http"
 
@@ -184,7 +183,7 @@ func (l *LokiSource) ConfigureByDSN(dsn string, labels map[string]string, logger
 	if d := params.Get("delay_for"); d != "" {
 		l.Config.DelayFor, err = time.ParseDuration(d)
 		if err != nil {
-			return errors.Wrap(err, "can't parse since in DSN configuration")
+			return fmt.Errorf("invalid duration: %w", err)
 		}
 		if l.Config.DelayFor < 0*time.Second || l.Config.DelayFor > 5*time.Second {
 			return errors.New("delay_for should be a value between 1s and 5s")
@@ -196,14 +195,14 @@ func (l *LokiSource) ConfigureByDSN(dsn string, labels map[string]string, logger
 	if s := params.Get("since"); s != "" {
 		l.Config.Since, err = time.ParseDuration(s)
 		if err != nil {
-			return errors.Wrap(err, "can't parse since in DSN configuration")
+			return fmt.Errorf("invalid since in dsn: %w", err)
 		}
 	}
 
 	if limit := params.Get("limit"); limit != "" {
 		limit, err := strconv.Atoi(limit)
 		if err != nil {
-			return errors.Wrap(err, "can't parse limit in DSN configuration")
+			return fmt.Errorf("invalid limit in dsn: %w", err)
 		}
 		l.Config.Limit = limit
 	} else {
@@ -213,7 +212,7 @@ func (l *LokiSource) ConfigureByDSN(dsn string, labels map[string]string, logger
 	if logLevel := params.Get("log_level"); logLevel != "" {
 		level, err := log.ParseLevel(logLevel)
 		if err != nil {
-			return errors.Wrap(err, "can't parse log_level in DSN configuration")
+			return fmt.Errorf("invalid log_level in dsn: %w", err)
 		}
 		l.Config.LogLevel = &level
 		l.logger.Logger.SetLevel(level)
@@ -237,7 +236,7 @@ func (l *LokiSource) ConfigureByDSN(dsn string, labels map[string]string, logger
 	}
 
 	l.Client = lokiclient.NewLokiClient(clientConfig)
-	l.Client.Logger = logger.WithField("component", "lokiclient")
+	l.Client.Logger = logger.WithFields(log.Fields{"component": "lokiclient", "source": l.Config.URL})
 
 	return nil
 }
@@ -257,7 +256,7 @@ func (l *LokiSource) OneShotAcquisition(out chan types.Event, t *tomb.Tomb) erro
 	defer cancel()
 	err := l.Client.Ready(readyCtx)
 	if err != nil {
-		return errors.Wrap(err, "loki is not ready")
+		return fmt.Errorf("loki is not ready: %w", err)
 	}
 
 	ctx, cancel := context.WithCancel(context.Background())
@@ -307,16 +306,16 @@ func (l *LokiSource) StreamingAcquisition(out chan types.Event, t *tomb.Tomb) er
 	defer cancel()
 	err := l.Client.Ready(readyCtx)
 	if err != nil {
-		return errors.Wrap(err, "loki is not ready")
+		return fmt.Errorf("loki is not ready: %w", err)
 	}
-	ll := l.logger.WithField("websocket url", l.lokiWebsocket)
+	ll := l.logger.WithField("websocket_url", l.lokiWebsocket)
 	t.Go(func() error {
 		ctx, cancel := context.WithCancel(context.Background())
 		defer cancel()
 		respChan, err := l.Client.Tail(ctx)
 		if err != nil {
 			ll.Errorf("could not start loki tail: %s", err)
-			return errors.Wrap(err, "could not start loki tail")
+			return fmt.Errorf("while starting loki tail: %w", err)
 		}
 		for {
 			select {
@@ -327,8 +326,7 @@ func (l *LokiSource) StreamingAcquisition(out chan types.Event, t *tomb.Tomb) er
 				}
 				if len(resp.DroppedEntries) > 0 {
 					entriesDropped.With(prometheus.Labels{"source": l.Config.URL}).Add(float64(len(resp.DroppedEntries)))
-					ll.WithField("query", l.Config.Query)
-					ll.Warnf("%d entries dropped from loki response", len(resp.DroppedEntries))
+					ll.WithField("query", l.Config.Query).Warnf("%d entries dropped from loki response", len(resp.DroppedEntries))
 				}
 				for _, stream := range resp.Streams {
 					for _, entry := range stream.Entries {