Use const errors instead of numbers

Author: informalict

agency/agency_health.go

@@ -25,6 +25,7 @@ package agency
 import (
 	"context"
 	"fmt"
+	"net/http"
 	"net/url"
 	"strings"
 	"sync"
@@ -84,7 +85,7 @@ func AreAgentsHealthy(ctx context.Context, clients []driver.Connection) error {
 					statuses[i].LeaderEndpoint = strings.Join(c.Endpoints(), ",")
 					statuses[i].IsResponding = true
 				} else {
-					if driver.IsArangoErrorWithCode(err, 307) && resp != nil {
+					if driver.IsArangoErrorWithCode(err, http.StatusTemporaryRedirect) && resp != nil {
 						location := resp.Header("Location")
 						// Valid response from a follower
 						statuses[i].IsLeader = false

client_impl.go

@@ -85,7 +85,8 @@ func (c *client) SynchronizeEndpoints2(ctx context.Context, dbname string) error
 	cep, err := c.clusterEndpoints(ctx, dbname)
 	if err != nil {
 		// ignore Forbidden: automatic failover is not enabled errors
-		if !IsArangoErrorWithErrorNum(err, 403, 501, 0, 9, 11) { // 3.2 returns no error code, thus check for 0
+		if !IsArangoErrorWithErrorNum(err, ErrHttpForbidden, ErrHttpInternal, 0, ErrNotImplemented, ErrForbidden) {
+			// 3.2 returns no error code, thus check for 0
 			// 501 with ErrorNum 9 is in there since 3.7, earlier versions returned 403 and ErrorNum 11.
 			return WithStack(err)
 		}

error.go

@@ -31,6 +31,33 @@ import (
 	"os"
 )
 
+const (
+	// general errors
+	ErrNotImplemented = 9
+	ErrForbidden      = 11
+	ErrDisabled       = 36
+
+	// HTTP error status codes
+	ErrHttpForbidden            = 403
+	ErrHttpInternal  = 501
+
+	// Internal ArangoDB storage errors
+	ErrArangoReadOnly = 1004
+
+	// General ArangoDB storage errors
+	ErrArangoConflict                 = 1200
+	ErrArangoDocumentNotFound         = 1202
+	ErrArangoDataSourceNotFound       = 1203
+	ErrArangoUniqueConstraintViolated = 1210
+
+	// ArangoDB cluster errors
+	ErrClusterLeadershipChallengeOngoing = 1495
+	ErrClusterNotLeader                  = 1496
+
+	// User management errors
+	ErrUserDuplicate = 1702
+)
+
 // ArangoError is a Go error with arangodb specific error information.
 type ArangoError struct {
 	HasError     bool   `json:"error"`
@@ -95,42 +122,46 @@ func IsArangoErrorWithErrorNum(err error, errorNum ...int) bool {
 
 // IsInvalidRequest returns true if the given error is an ArangoError with code 400, indicating an invalid request.
 func IsInvalidRequest(err error) bool {
-	return IsArangoErrorWithCode(err, 400)
+	return IsArangoErrorWithCode(err, http.StatusBadRequest)
+
 }
 
 // IsUnauthorized returns true if the given error is an ArangoError with code 401, indicating an unauthorized request.
 func IsUnauthorized(err error) bool {
-	return IsArangoErrorWithCode(err, 401)
+	return IsArangoErrorWithCode(err, http.StatusUnauthorized)
 }
 
 // IsForbidden returns true if the given error is an ArangoError with code 403, indicating a forbidden request.
 func IsForbidden(err error) bool {
-	return IsArangoErrorWithCode(err, 403)
+	return IsArangoErrorWithCode(err, http.StatusForbidden)
 }
 
 // IsNotFound returns true if the given error is an ArangoError with code 404, indicating a object not found.
 func IsNotFound(err error) bool {
-	return IsArangoErrorWithCode(err, 404) || IsArangoErrorWithErrorNum(err, 1202, 1203)
+	return IsArangoErrorWithCode(err, http.StatusNotFound) ||
+		IsArangoErrorWithErrorNum(err, ErrArangoDocumentNotFound, ErrArangoDataSourceNotFound)
 }
 
 // IsConflict returns true if the given error is an ArangoError with code 409, indicating a conflict.
 func IsConflict(err error) bool {
-	return IsArangoErrorWithCode(err, 409) || IsArangoErrorWithErrorNum(err, 1702)
+	return IsArangoErrorWithCode(err, http.StatusConflict) || IsArangoErrorWithErrorNum(err, ErrUserDuplicate)
 }
 
 // IsPreconditionFailed returns true if the given error is an ArangoError with code 412, indicating a failed precondition.
 func IsPreconditionFailed(err error) bool {
-	return IsArangoErrorWithCode(err, 412) || IsArangoErrorWithErrorNum(err, 1200, 1210)
+	return IsArangoErrorWithCode(err, http.StatusPreconditionFailed) ||
+		IsArangoErrorWithErrorNum(err, ErrArangoConflict, ErrArangoUniqueConstraintViolated)
 }
 
 // IsNoLeader returns true if the given error is an ArangoError with code 503 error number 1496.
 func IsNoLeader(err error) bool {
-	return IsArangoErrorWithCode(err, 503) && IsArangoErrorWithErrorNum(err, 1496)
+	return IsArangoErrorWithCode(err, http.StatusServiceUnavailable) && IsArangoErrorWithErrorNum(err, ErrClusterNotLeader)
 }
 
 // IsNoLeaderOrOngoing return true if the given error is an ArangoError with code 503 and error number 1496 or 1495
 func IsNoLeaderOrOngoing(err error) bool {
-	return IsArangoErrorWithCode(err, 503) && (IsArangoErrorWithErrorNum(err, 1495) || IsArangoErrorWithErrorNum(err, 1496))
+	return IsArangoErrorWithCode(err, http.StatusServiceUnavailable) &&
+		IsArangoErrorWithErrorNum(err, ErrClusterLeadershipChallengeOngoing, ErrClusterNotLeader)
 }
 
 // InvalidArgumentError is returned when a go function argument is invalid.

test/server_statistics_test.go

@@ -35,7 +35,7 @@ import (
 func checkEnabled(t *testing.T, c driver.Client, ctx context.Context) {
 	_, err := c.Statistics(ctx)
 	if err != nil {
-		if driver.IsArangoErrorWithErrorNum(err, 36) {
+		if driver.IsArangoErrorWithErrorNum(err, driver.ErrDisabled) {
 			t.Skip("Statistics disabled.")
 		}
 		t.Fatalf("Statistics failed: %s", describe(err))

test/view_test.go

@@ -25,6 +25,7 @@ package test
 import (
 	"context"
 	"fmt"
+	"net/http"
 	"testing"
 
 	driver "github.com/arangodb/go-driver"
@@ -577,7 +578,7 @@ func TestArangoSearchPrimarySort(t *testing.T) {
 	}{
 		{
 			Name:      "NoneSet",
-			ErrorCode: 400, // Bad Parameter
+			ErrorCode: http.StatusBadRequest, // Bad Parameter
 		},
 		{
 			Name:              "AscTrue",
@@ -603,25 +604,25 @@ func TestArangoSearchPrimarySort(t *testing.T) {
 			Name:        "SetBothAsc",
 			InDirection: &directionAsc,
 			InAscending: &boolTrue,
-			ErrorCode:   400,
+			ErrorCode:   http.StatusBadRequest,
 		},
 		{
 			Name:        "SetBothDesc",
 			InDirection: &directionDesc,
 			InAscending: &boolFalse,
-			ErrorCode:   400,
+			ErrorCode:   http.StatusBadRequest,
 		},
 		{
 			Name:        "DirAscAscFalse",
 			InDirection: &directionAsc,
 			InAscending: &boolTrue,
-			ErrorCode:   400,
+			ErrorCode:   http.StatusBadRequest,
 		},
 		{
 			Name:        "DirDescAscTrue",
 			InDirection: &directionAsc,
 			InAscending: &boolTrue,
-			ErrorCode:   400,
+			ErrorCode:   http.StatusBadRequest,
 		},
 	}