fix(style): error strings should not be capitalized or end with punctuation or a newline

assets.go

@@ -36,7 +36,7 @@ func newBinaryFileSystem(root string) *binaryFileSystem {
 		Asset: Asset,
 		// Don't render directory index, return 404 for /static/ requests)
 		AssetDir: func(path string) ([]string, error) {
-			return nil, errors.New("Not found")
+			return nil, errors.New("not found")
 		},
 		Prefix: root,
 	}

internal/alertmanager/models.go

@@ -360,7 +360,7 @@ func (am *Alertmanager) SilenceByID(id string) (models.Silence, error) {
 
 	s, found := am.silences[id]
 	if !found {
-		return models.Silence{}, fmt.Errorf("Silence '%s' not found", id)
+		return models.Silence{}, fmt.Errorf("silence '%s' not found", id)
 	}
 	return s, nil
 }

internal/alertmanager/upstream.go

@@ -59,12 +59,12 @@ func NewAlertmanager(name, upstreamURI string, opts ...Option) (*Alertmanager, e
 // instances used when pulling alerts from upstreams
 func RegisterAlertmanager(am *Alertmanager) error {
 	if _, found := upstreams[am.Name]; found {
-		return fmt.Errorf("Alertmanager upstream '%s' already exist", am.Name)
+		return fmt.Errorf("alertmanager upstream '%s' already exist", am.Name)
 	}
 
 	for _, existingAM := range upstreams {
 		if existingAM.URI == am.URI {
-			return fmt.Errorf("Alertmanager upstream '%s' already collects from '%s'", existingAM.Name, existingAM.URI)
+			return fmt.Errorf("alertmanager upstream '%s' already collects from '%s'", existingAM.Name, existingAM.URI)
 		}
 	}
 	upstreams[am.Name] = am

internal/mapper/mapper.go

@@ -44,7 +44,7 @@ func GetAlertMapper(version string) (AlertMapper, error) {
 			return m, nil
 		}
 	}
-	return nil, fmt.Errorf("Can't find alert mapper for Alertmanager %s", version)
+	return nil, fmt.Errorf("can't find alert mapper for Alertmanager %s", version)
 }
 
 // RegisterSilenceMapper allows to register mapper implementing silence data
@@ -60,5 +60,5 @@ func GetSilenceMapper(version string) (SilenceMapper, error) {
 			return m, nil
 		}
 	}
-	return nil, fmt.Errorf("Can't find silence mapper for Alertmanager %s", version)
+	return nil, fmt.Errorf("can't find silence mapper for Alertmanager %s", version)
 }

internal/mock/mock.go

@@ -26,7 +26,7 @@ func RegisterURL(url string, version string, filename string) {
 		panic(err)
 	}
 	if len(mockJSON) == 0 {
-		panic(fmt.Errorf("Empty mock file '%s'", fullPath))
+		panic(fmt.Errorf("empty mock file '%s'", fullPath))
 	}
 	httpmock.RegisterResponder("GET", url, httpmock.NewBytesResponder(200, mockJSON))
 }

internal/uri/http.go

@@ -29,7 +29,7 @@ func (r *HTTPURIReader) Read(uri string) (io.ReadCloser, error) {
 	}
 
 	if resp.StatusCode != http.StatusOK {
-		return nil, fmt.Errorf("Request to %s failed with %s", SanitizeURI(uri), resp.Status)
+		return nil, fmt.Errorf("request to %s failed with %s", SanitizeURI(uri), resp.Status)
 	}
 
 	var reader io.ReadCloser
@@ -37,7 +37,7 @@ func (r *HTTPURIReader) Read(uri string) (io.ReadCloser, error) {
 	case "gzip":
 		reader, err = gzip.NewReader(resp.Body)
 		if err != nil {
-			return nil, fmt.Errorf("Failed to decode gzipped content: %s", err.Error())
+			return nil, fmt.Errorf("failed to decode gzipped content: %s", err.Error())
 		}
 	default:
 		reader = resp.Body

internal/uri/uri.go

@@ -31,6 +31,6 @@ func NewReader(uri string, timeout time.Duration, clientTransport http.RoundTrip
 	case "file":
 		return &FileURIReader{}, nil
 	default:
-		return nil, fmt.Errorf("Unsupported URI scheme '%s' in '%s'", u.Scheme, u)
+		return nil, fmt.Errorf("unsupported URI scheme '%s' in '%s'", u.Scheme, u)
 	}
 }