Improve returning individual message errors from Beacon API (#15835)

* Improve returning individual message errors from Beacon API

* changelog <3

* fix test

* add debug logs

* batch broadcast errors

* use logrus fields

* capitalize log messages

api/client/beacon/client.go

@@ -284,7 +284,7 @@ func (c *Client) SubmitChangeBLStoExecution(ctx context.Context, request []*stru
 	if resp.StatusCode != http.StatusOK {
 		decoder := json.NewDecoder(resp.Body)
 		decoder.DisallowUnknownFields()
-		errorJson := &server.IndexedVerificationFailureError{}
+		errorJson := &server.IndexedErrorContainer{}
 		if err := decoder.Decode(errorJson); err != nil {
 			return errors.Wrapf(err, "failed to decode error JSON for %s", resp.Request.URL)
 		}

api/server/error.go

@@ -6,6 +6,11 @@ import (
 	"strings"
 )
 
+var (
+	ErrIndexedValidationFail = "One or more messages failed validation"
+	ErrIndexedBroadcastFail  = "One or more messages failed broadcast"
+)
+
 // DecodeError represents an error resulting from trying to decode an HTTP request.
 // It tracks the full field name for which decoding failed.
 type DecodeError struct {
@@ -29,19 +34,38 @@ func (e *DecodeError) Error() string {
 	return fmt.Sprintf("could not decode %s: %s", strings.Join(e.path, "."), e.err.Error())
 }
 
-// IndexedVerificationFailureError wraps a collection of verification failures.
-type IndexedVerificationFailureError struct {
-	Message  string                        `json:"message"`
-	Code     int                           `json:"code"`
-	Failures []*IndexedVerificationFailure `json:"failures"`
+// IndexedErrorContainer wraps a collection of indexed errors.
+type IndexedErrorContainer struct {
+	Message  string          `json:"message"`
+	Code     int             `json:"code"`
+	Failures []*IndexedError `json:"failures"`
 }
 
-func (e *IndexedVerificationFailureError) StatusCode() int {
+func (e *IndexedErrorContainer) StatusCode() int {
 	return e.Code
 }
 
-// IndexedVerificationFailure represents an issue when verifying a single indexed object e.g. an item in an array.
-type IndexedVerificationFailure struct {
+// IndexedError represents an issue when processing a single indexed object e.g. an item in an array.
+type IndexedError struct {
 	Index   int    `json:"index"`
 	Message string `json:"message"`
 }
+
+// BroadcastFailedError represents an error scenario where broadcasting a published message failed.
+type BroadcastFailedError struct {
+	msg string
+	err error
+}
+
+// NewBroadcastFailedError creates a new instance of BroadcastFailedError.
+func NewBroadcastFailedError(msg string, err error) *BroadcastFailedError {
+	return &BroadcastFailedError{
+		msg: msg,
+		err: err,
+	}
+}
+
+// Error returns the underlying error message.
+func (e *BroadcastFailedError) Error() string {
+	return fmt.Sprintf("could not broadcast %s: %s", e.msg, e.err.Error())
+}