blockchain: Add ldbErr to error description.

Add the reason for bad inserts, updates, and deletes to the error
description.

blockchain/upgrade.go

@@ -5061,7 +5061,7 @@ func migrateUtxoDbBuckets(ctx context.Context, utxoBackend UtxoBackend) error {
 			numMigrated++
 		}
 		if iterErr := iter.Error(); iterErr != nil {
-			return false, convertLdbErr(iterErr, iterErr.Error())
+			return false, convertLdbErr(iterErr, "failed to run batch")
 		}
 		isFullyDone := err == nil
 		if (isFullyDone || logProgress) && numMigrated > 0 {
@@ -5202,7 +5202,7 @@ func moveUtxoDatabase(ctx context.Context, oldPath string, newPath string) error
 	// Open the database at the old path.
 	oldDb, err := leveldb.OpenFile(oldPath, &opts)
 	if err != nil {
-		str := fmt.Sprintf("failed to open UTXO database at old path: %v", err)
+		str := "failed to open UTXO database at old path"
 		return convertLdbErr(err, str)
 	}
 
@@ -5212,7 +5212,7 @@ func moveUtxoDatabase(ctx context.Context, oldPath string, newPath string) error
 		if err := oldDb.Close(); err != nil {
 			return convertLdbErr(err, "failed to close UTXO database at old path")
 		}
-		str := fmt.Sprintf("failed to open UTXO database at new path: %v", err)
+		str := "failed to open UTXO database at new path"
 		return convertLdbErr(err, str)
 	}
 
@@ -5265,7 +5265,7 @@ func moveUtxoDatabase(ctx context.Context, oldPath string, newPath string) error
 			numMigrated++
 		}
 		if iterErr := iter.Error(); iterErr != nil {
-			return false, convertLdbErr(iterErr, iterErr.Error())
+			return false, convertLdbErr(iterErr, "failed to run batch")
 		}
 		isFullyDone := err == nil
 		if (isFullyDone || logProgress) && numMigrated > 0 {

blockchain/utxobackend.go

@@ -251,7 +251,7 @@ var _ UtxoBackend = (*levelDbUtxoBackend)(nil)
 
 // convertLdbErr converts the passed leveldb error into a context error with an
 // equivalent error kind and the passed description.  It also sets the passed
-// error as the underlying error.
+// error as the underlying error and adds its error string to the description.
 func convertLdbErr(ldbErr error, desc string) ContextError {
 	// Use the general UTXO backend error kind by default.  The code below will
 	// update this with the converted error if it's recognized.
@@ -273,6 +273,9 @@ func convertLdbErr(ldbErr error, desc string) ContextError {
 		kind = ErrUtxoBackendTxClosed
 	}
 
+	// Include the original error in description.
+	desc = fmt.Sprintf("%s: %v", desc, ldbErr)
+
 	err := contextError(kind, desc)
 	err.RawErr = ldbErr
 
@@ -364,8 +367,7 @@ func LoadUtxoDB(ctx context.Context, params *chaincfg.Params, dataDir string) (*
 	}
 	db, err := leveldb.OpenFile(dbPath, &opts)
 	if err != nil {
-		str := fmt.Sprintf("failed to open UTXO database: %v", err)
-		return nil, convertLdbErr(err, str)
+		return nil, convertLdbErr(err, "failed to open UTXO database")
 	}
 
 	log.Info("UTXO database loaded")
@@ -573,7 +575,7 @@ func (l *levelDbUtxoBackend) FetchStats() (*UtxoStats, error) {
 		stats.Total += entry.amount
 	}
 	if err := iter.Error(); err != nil {
-		return nil, convertLdbErr(err, err.Error())
+		return nil, convertLdbErr(err, "failed to fetch stats")
 	}
 
 	stats.SerializedHash = standalone.CalcMerkleRootInPlace(leaves)

blockchain/utxobackend_test.go

@@ -6,6 +6,7 @@ package blockchain
 
 import (
 	"errors"
+	"fmt"
 	"reflect"
 	"testing"
 	"time"
@@ -47,7 +48,7 @@ func TestConvertLdbErr(t *testing.T) {
 		want:   ErrUtxoBackend,
 	}, {
 		name:   "Corruption error",
-		ldbErr: &ldberrors.ErrCorrupted{},
+		ldbErr: &ldberrors.ErrCorrupted{Err: errors.New("corrupted")},
 		desc:   "Some corruption error occurred",
 		want:   ErrUtxoBackendCorruption,
 	}, {
@@ -78,10 +79,11 @@ func TestConvertLdbErr(t *testing.T) {
 			continue
 		}
 
+		wantDesc := fmt.Sprintf("%s: %v", test.desc, test.ldbErr)
 		// Validate the error description.
-		if gotErr.Description != test.desc {
+		if gotErr.Description != wantDesc {
 			t.Errorf("%q: mismatched error description:\nwant: %v\n got: %v\n",
-				test.name, test.desc, gotErr.Description)
+				test.name, wantDesc, gotErr.Description)
 			continue
 		}