Repository: owncloud/ocis
Pull request #7351 (2023-09-25 15:59:54)

graph/education: Check school number for duplicates before adding a school
Fixes https://github.com/owncloud/enterprise/issues/6051

Also contains a few minor cleanups. E.g. to make returned errors more consistent.

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[![0.0%](https://sonarsource.github.io/sonarcloud-github-static-resources/v2/checks/Duplications/3-16px.png '0.0%')](https://sonarcloud.io/component_measures?id=owncloud_ocis&pullRequest=7351&metric=new_duplicated_lines_density&view=list) [0.0% Duplication](https://sonarcloud.io/component_measures?id=owncloud_ocis&pullRequest=7351&metric=new_duplicated_lines_density&view=list)


micbar: Please backport after merging to stable-4.0 including the changelog

Patch:
diff --git a/changelog/unreleased/fix-graph-education-createschool.md b/changelog/unreleased/fix-graph-education-createschool.md
new file mode 100644
index 00000000000..4d867a4556f
--- /dev/null
+++ b/changelog/unreleased/fix-graph-education-createschool.md
@@ -0,0 +1,6 @@
+Bugfix: Check school number for duplicates before adding a school
+
+We fixed an issue that allowed to create two schools with the same school number
+
+https://github.com/owncloud/ocis/pull/7351
+https://github.com/owncloud/enterprise/issues/6051
diff --git a/services/graph/pkg/identity/ldap_education_school.go b/services/graph/pkg/identity/ldap_education_school.go
index 6274c2e8f0b..fe02f4b262b 100644
--- a/services/graph/pkg/identity/ldap_education_school.go
+++ b/services/graph/pkg/identity/ldap_education_school.go
@@ -49,7 +49,11 @@ const (
 
 const ldapDateFormat = "20060102150405Z0700"
 
-var errNotSet = errors.New("Attribute not set")
+var (
+	errNotSet             = errors.New("Attribute not set")
+	errSchoolNameExists   = errorcode.New(errorcode.NameAlreadyExists, "A school with that name is already present")
+	errSchoolNumberExists = errorcode.New(errorcode.NameAlreadyExists, "A school with that number is already present")
+)
 
 func defaultEducationConfig() educationConfig {
 	return educationConfig{
@@ -116,7 +120,18 @@ func (i *LDAP) CreateEducationSchool(ctx context.Context, school libregraph.Educ
 		return nil, ErrReadOnly
 	}
 
-	// Here we should verify that the school number is not already used
+	// Check that the school number is not already used
+	_, err := i.getSchoolByNumber(school.GetSchoolNumber())
+	switch err {
+	case nil:
+		logger.Debug().Err(errSchoolNumberExists).Str("schoolNumber", school.GetSchoolNumber()).Msg("duplicate school number")
+		return nil, errSchoolNumberExists
+	case ErrNotFound:
+		break
+	default:
+		logger.Error().Err(err).Str("schoolNumber", school.GetSchoolNumber()).Msg("error looking up school by number")
+		return nil, errorcode.New(errorcode.GeneralException, "error looking up school by number")
+	}
 
 	attributeTypeAndValue := ldap.AttributeTypeAndValue{
 		Type:  i.educationConfig.schoolAttributeMap.displayName,
@@ -141,7 +156,7 @@ func (i *LDAP) CreateEducationSchool(ctx context.Context, school libregraph.Educ
 		logger.Debug().Err(err).Msg("error adding school")
 		if errors.As(err, &lerr) {
 			if lerr.ResultCode == ldap.LDAPResultEntryAlreadyExists {
-				err = errorcode.New(errorcode.NameAlreadyExists, lerr.Error())
+				err = errSchoolNameExists
 			}
 		}
 		return nil, err
@@ -156,7 +171,7 @@ func (i *LDAP) CreateEducationSchool(ctx context.Context, school libregraph.Educ
 }
 
 // UpdateEducationSchoolOperation contains the logic for which update operation to apply to a school
-func (i *LDAP) UpdateEducationSchoolOperation(
+func (i *LDAP) updateEducationSchoolOperation(
 	schoolUpdate libregraph.EducationSchool,
 	currentSchool libregraph.EducationSchool,
 ) schoolUpdateOperation {
@@ -216,7 +231,7 @@ func (i *LDAP) updateDisplayName(ctx context.Context, dn string, providedDisplay
 		logger.Debug().Err(err).Msg("error updating school name")
 		if errors.As(err, &lerr) {
 			if lerr.ResultCode == ldap.LDAPResultEntryAlreadyExists {
-				err = errorcode.New(errorcode.NameAlreadyExists, lerr.Error())
+				err = errSchoolNameExists
 			}
 		}
 		return err
@@ -233,11 +248,9 @@ func (i *LDAP) updateSchoolProperties(ctx context.Context, dn string, currentSch
 	mr := ldap.NewModifyRequest(dn, nil)
 	if updatedSchoolNumber, ok := updatedSchool.GetSchoolNumberOk(); ok {
 		if *updatedSchoolNumber != "" && currentSchool.GetSchoolNumber() != *updatedSchoolNumber {
-			_, err := i.getSchoolByNumberOrID(*updatedSchoolNumber)
+			_, err := i.getSchoolByNumber(*updatedSchoolNumber)
 			if err == nil {
-				errmsg := fmt.Sprintf("school number '%s' already exists", *updatedSchoolNumber)
-				err = fmt.Errorf(errmsg)
-				return err
+				return errSchoolNumberExists
 			}
 			mr.Replace(i.educationConfig.schoolAttributeMap.schoolNumber, []string{*updatedSchoolNumber})
 		}
@@ -255,13 +268,7 @@ func (i *LDAP) updateSchoolProperties(ctx context.Context, dn string, currentSch
 	}
 
 	if err := i.conn.Modify(mr); err != nil {
-		var lerr *ldap.Error
 		logger.Debug().Err(err).Msg("error updating school number")
-		if errors.As(err, &lerr) {
-			if lerr.ResultCode == ldap.LDAPResultEntryAlreadyExists {
-				err = errorcode.New(errorcode.NameAlreadyExists, lerr.Error())
-			}
-		}
 		return err
 	}
 
@@ -282,7 +289,7 @@ func (i *LDAP) UpdateEducationSchool(ctx context.Context, numberOrID string, sch
 	}
 
 	currentSchool := i.createSchoolModelFromLDAP(e)
-	switch i.UpdateEducationSchoolOperation(school, *currentSchool) {
+	switch i.updateEducationSchoolOperation(school, *currentSchool) {
 	case tooManyValues:
 		return nil, fmt.Errorf("school name and school number cannot be updated in the same request")
 	case schoolUnchanged:
@@ -635,17 +642,12 @@ func (i *LDAP) RemoveClassFromEducationSchool(ctx context.Context, schoolNumberO
 }
 
 func (i *LDAP) getSchoolByDN(dn string) (*ldap.Entry, error) {
-	attrs := []string{
-		i.educationConfig.schoolAttributeMap.displayName,
-		i.educationConfig.schoolAttributeMap.id,
-		i.educationConfig.schoolAttributeMap.schoolNumber,
-	}
 	filter := fmt.Sprintf("(objectClass=%s)", i.educationConfig.schoolObjectClass)
 
 	if i.educationConfig.schoolFilter != "" {
 		filter = fmt.Sprintf("(&%s(%s))", filter, i.educationConfig.schoolFilter)
 	}
-	return i.getEntryByDN(dn, attrs, filter)
+	return i.getEntryByDN(dn, i.getEducationSchoolAttrTypes(), filter)
 }
 
 func (i *LDAP) getSchoolByNumberOrID(numberOrID string) (*ldap.Entry, error) {
@@ -660,6 +662,16 @@ func (i *LDAP) getSchoolByNumberOrID(numberOrID string) (*ldap.Entry, error) {
 	return i.getSchoolByFilter(filter)
 }
 
+func (i *LDAP) getSchoolByNumber(schoolNumber string) (*ldap.Entry, error) {
+	schoolNumber = ldap.EscapeFilter(schoolNumber)
+	filter := fmt.Sprintf(
+		"(%s=%s)",
+		i.educationConfig.schoolAttributeMap.schoolNumber,
+		schoolNumber,
+	)
+	return i.getSchoolByFilter(filter)
+}
+
 func (i *LDAP) getSchoolByFilter(filter string) (*ldap.Entry, error) {
 	filter = fmt.Sprintf("(&%s(objectClass=%s)%s)",
 		i.educationConfig.schoolFilter,
diff --git a/services/graph/pkg/service/v0/educationschools.go b/services/graph/pkg/service/v0/educationschools.go
index eb7b10d7e7b..8a176ef2057 100644
--- a/services/graph/pkg/service/v0/educationschools.go
+++ b/services/graph/pkg/service/v0/educationschools.go
@@ -148,7 +148,7 @@ func (g Graph) PatchEducationSchool(w http.ResponseWriter, r *http.Request) {
 
 	if school, err = g.identityEducationBackend.UpdateEducationSchool(r.Context(), schoolID, *school); err != nil {
 		logger.Debug().Err(err).Interface("school", school).Msg("could not update school: backend error")
-		errorcode.GeneralException.Render(w, r, http.StatusInternalServerError, err.Error())
+		errorcode.RenderError(w, r, err)
 		return
 	}
 
diff --git a/services/graph/pkg/service/v0/errorcode/errorcode.go b/services/graph/pkg/service/v0/errorcode/errorcode.go
index 6ac3b0a44a3..65b6beb5a4c 100644
--- a/services/graph/pkg/service/v0/errorcode/errorcode.go
+++ b/services/graph/pkg/service/v0/errorcode/errorcode.go
@@ -1,3 +1,4 @@
+// Package errorcode allows to deal with graph error codes
 package errorcode
 
 import (
@@ -13,6 +14,7 @@ import (
 // ErrorCode defines code as used in MS Graph - see https://docs.microsoft.com/en-us/graph/errors?context=graph%2Fapi%2F1.0&view=graph-rest-1.0
 type ErrorCode int
 
+// Error defines a custom error struct, containing and MS Graph error code an a textual error message
 type Error struct {
 	errorCode ErrorCode
 	msg       string
@@ -79,6 +81,7 @@ var errorCodes = [...]string{
 	"preconditionFailed",
 }
 
+// New constructs a new errorcode.Error
 func New(e ErrorCode, msg string) Error {
 	return Error{
 		errorCode: e,
@@ -86,7 +89,7 @@ func New(e ErrorCode, msg string) Error {
 	}
 }
 
-// Render writes an Graph ErrorObject to the response writer
+// Render writes an Graph ErrorCode	object to the response writer
 func (e ErrorCode) Render(w http.ResponseWriter, r *http.Request, status int, msg string) {
 	innererror := map[string]interface{}{
 		"date": time.Now().UTC().Format(time.RFC3339),
@@ -104,12 +107,14 @@ func (e ErrorCode) Render(w http.ResponseWriter, r *http.Request, status int, ms
 	render.JSON(w, r, resp)
 }
 
+// Render writes an Graph Error object to the response writer
 func (e Error) Render(w http.ResponseWriter, r *http.Request) {
 	var status int
 	switch e.errorCode {
 	case AccessDenied:
 		status = http.StatusForbidden
-	case InvalidRange:
+	case
+		InvalidRange:
 		status = http.StatusRequestedRangeNotSatisfiable
 	case InvalidRequest:
 		status = http.StatusBadRequest
@@ -125,12 +130,18 @@ func (e Error) Render(w http.ResponseWriter, r *http.Request) {
 	e.errorCode.Render(w, r, status, e.msg)
 }
 
+// String returns the string corresponding to the ErrorCode
 func (e ErrorCode) String() string {
 	return errorCodes[e]
 }
 
+// Error return the concatenation of the error string and optinal message
 func (e Error) Error() string {
-	return errorCodes[e.errorCode]
+	errString := errorCodes[e.errorCode]
+	if e.msg != "" {
+		errString += ": " + e.msg
+	}
+	return errString
 }
 
 // RenderError render the Graph Error based on a code or default one


Test patch:
diff --git a/services/graph/pkg/identity/ldap_education_class_test.go b/services/graph/pkg/identity/ldap_education_class_test.go
index b8f481b142d..b6f34cc8a3a 100644
--- a/services/graph/pkg/identity/ldap_education_class_test.go
+++ b/services/graph/pkg/identity/ldap_education_class_test.go
@@ -72,9 +72,7 @@ func TestGetEducationClasses(t *testing.T) {
 	lm.On("Search", mock.Anything).Return(nil, ldap.NewError(ldap.LDAPResultOperationsError, errors.New("mock")))
 	b, _ := getMockedBackend(lm, lconfig, &logger)
 	_, err := b.GetEducationClasses(context.Background())
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 
 	lm = &mocks.Client{}
 	lm.On("Search", mock.Anything).Return(&ldap.SearchResult{}, nil)
@@ -156,7 +154,7 @@ func TestGetEducationClass(t *testing.T) {
 
 		if tt.expectedItemNotFound {
 			assert.NotNil(t, err)
-			assert.Equal(t, "itemNotFound", err.Error())
+			assert.Equal(t, "itemNotFound: not found", err.Error())
 		} else {
 			assert.Nil(t, err)
 			assert.Equal(t, "Math", class.GetDisplayName())
@@ -228,7 +226,7 @@ func TestDeleteEducationClass(t *testing.T) {
 		if tt.expectedItemNotFound {
 			lm.AssertNumberOfCalls(t, "Del", 0)
 			assert.NotNil(t, err)
-			assert.Equal(t, "itemNotFound", err.Error())
+			assert.Equal(t, "itemNotFound: not found", err.Error())
 		} else {
 			assert.Nil(t, err)
 		}
@@ -301,7 +299,7 @@ func TestGetEducationClassMembers(t *testing.T) {
 		if tt.expectedItemNotFound {
 			lm.AssertNumberOfCalls(t, "Search", 1)
 			assert.NotNil(t, err)
-			assert.Equal(t, "itemNotFound", err.Error())
+			assert.Equal(t, "itemNotFound: not found", err.Error())
 		} else {
 			lm.AssertNumberOfCalls(t, "Search", 2)
 			assert.Nil(t, err)
diff --git a/services/graph/pkg/identity/ldap_education_school_test.go b/services/graph/pkg/identity/ldap_education_school_test.go
index d0e06353b70..520cdc5c900 100644
--- a/services/graph/pkg/identity/ldap_education_school_test.go
+++ b/services/graph/pkg/identity/ldap_education_school_test.go
@@ -2,6 +2,7 @@ package identity
 
 import (
 	"context"
+	"errors"
 	"testing"
 	"time"
 
@@ -9,6 +10,7 @@ import (
 	libregraph "github.com/owncloud/libre-graph-api-go"
 	"github.com/owncloud/ocis/v2/services/graph/mocks"
 	"github.com/owncloud/ocis/v2/services/graph/pkg/config"
+	"github.com/owncloud/ocis/v2/services/graph/pkg/service/v0/errorcode"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/mock"
 )
@@ -67,45 +69,135 @@ var (
 )
 
 func TestCreateEducationSchool(t *testing.T) {
-	lm := &mocks.Client{}
-
-	ldapSchoolAddRequestMatcher := func(ar *ldap.AddRequest) bool {
-		if ar.DN != "ou=Test School," {
-			return false
-		}
-		for _, attr := range ar.Attributes {
-			if attr.Type == "ocEducationSchoolTerminationTimestamp" {
+	tests := []struct {
+		name          string
+		schoolNumber  string
+		schoolName    string
+		expectedError error
+	}{
+		{
+			name:          "Create a Education School succeeds",
+			schoolNumber:  "0123",
+			schoolName:    "Test School",
+			expectedError: nil,
+		}, {
+			name:          "Create a Education School with a duplicated Schoolnumber fails with an error",
+			schoolNumber:  "0666",
+			schoolName:    "Test School",
+			expectedError: errorcode.New(errorcode.NameAlreadyExists, "A school with that number is already present"),
+		}, {
+			name:          "Create a Education School with a duplicated Name fails with an error",
+			schoolNumber:  "0123",
+			schoolName:    "Existing Test School",
+			expectedError: errorcode.New(errorcode.NameAlreadyExists, "A school with that name is already present"),
+		}, {
+			name:          "Create a Education School fails, when there is a backend error",
+			schoolNumber:  "1111",
+			schoolName:    "Test School",
+			expectedError: errorcode.New(errorcode.GeneralException, "error looking up school by number"),
+		},
+	}
+	for _, tt := range tests {
+		lm := &mocks.Client{}
+		ldapSchoolGoodAddRequestMatcher := func(ar *ldap.AddRequest) bool {
+			if ar.DN != "ou=Test School," {
 				return false
 			}
+			for _, attr := range ar.Attributes {
+				if attr.Type == "ocEducationSchoolTerminationTimestamp" {
+					return false
+				}
+			}
+			return true
 		}
-		return true
-	}
-
-	lm.On("Add", mock.MatchedBy(ldapSchoolAddRequestMatcher)).Return(nil)
+		lm.On("Add", mock.MatchedBy(ldapSchoolGoodAddRequestMatcher)).Return(nil)
 
-	lm.On("Search", mock.Anything).
-		Return(
-			&ldap.SearchResult{
-				Entries: []*ldap.Entry{schoolEntry},
-			},
-			nil)
+		ldapExistingSchoolAddRequestMatcher := func(ar *ldap.AddRequest) bool {
+			if ar.DN == "ou=Existing Test School," {
+				return true
+			}
+			return false
+		}
+		lm.On("Add", mock.MatchedBy(ldapExistingSchoolAddRequestMatcher)).Return(ldap.NewError(ldap.LDAPResultEntryAlreadyExists, errors.New("")))
 
-	b, err := getMockedBackend(lm, eduConfig, &logger)
-	assert.Nil(t, err)
-	assert.NotEqual(t, "", b.educationConfig.schoolObjectClass)
-	school := libregraph.NewEducationSchool()
-	school.SetDisplayName("Test School")
-	school.SetSchoolNumber("0123")
-	school.SetId("abcd-defg")
-	res_school, err := b.CreateEducationSchool(context.Background(), *school)
-	lm.AssertNumberOfCalls(t, "Add", 1)
-	lm.AssertNumberOfCalls(t, "Search", 1)
-	assert.Nil(t, err)
-	assert.NotNil(t, res_school)
-	assert.Equal(t, res_school.GetDisplayName(), school.GetDisplayName())
-	assert.Equal(t, res_school.GetId(), school.GetId())
-	assert.Equal(t, res_school.GetSchoolNumber(), school.GetSchoolNumber())
-	assert.False(t, res_school.HasTerminationDate())
+		schoolNumberSearchRequest := &ldap.SearchRequest{
+			BaseDN:     "",
+			Scope:      2,
+			SizeLimit:  1,
+			Filter:     "(&(objectClass=ocEducationSchool)(ocEducationSchoolNumber=0123))",
+			Attributes: []string{"ou", "owncloudUUID", "ocEducationSchoolNumber", "ocEducationSchoolTerminationTimestamp"},
+			Controls:   []ldap.Control(nil),
+		}
+		lm.On("Search", schoolNumberSearchRequest).
+			Return(
+				&ldap.SearchResult{
+					Entries: []*ldap.Entry{},
+				},
+				nil)
+		existingSchoolNumberSearchRequest := &ldap.SearchRequest{
+			BaseDN:     "",
+			Scope:      2,
+			SizeLimit:  1,
+			Filter:     "(&(objectClass=ocEducationSchool)(ocEducationSchoolNumber=0666))",
+			Attributes: []string{"ou", "owncloudUUID", "ocEducationSchoolNumber", "ocEducationSchoolTerminationTimestamp"},
+			Controls:   []ldap.Control(nil),
+		}
+		lm.On("Search", existingSchoolNumberSearchRequest).
+			Return(
+				&ldap.SearchResult{
+					Entries: []*ldap.Entry{schoolEntry},
+				},
+				nil)
+		schoolNumberSearchRequestError := &ldap.SearchRequest{
+			BaseDN:     "",
+			Scope:      2,
+			SizeLimit:  1,
+			Filter:     "(&(objectClass=ocEducationSchool)(ocEducationSchoolNumber=1111))",
+			Attributes: []string{"ou", "owncloudUUID", "ocEducationSchoolNumber", "ocEducationSchoolTerminationTimestamp"},
+			Controls:   []ldap.Control(nil),
+		}
+		lm.On("Search", schoolNumberSearchRequestError).
+			Return(
+				&ldap.SearchResult{
+					Entries: []*ldap.Entry{},
+				},
+				ldap.NewError(ldap.LDAPResultOther, errors.New("some error")))
+		schoolLookupAfterCreate := &ldap.SearchRequest{
+			BaseDN:     "ou=Test School,",
+			Scope:      0,
+			SizeLimit:  1,
+			Filter:     "(objectClass=ocEducationSchool)",
+			Attributes: []string{"ou", "owncloudUUID", "ocEducationSchoolNumber", "ocEducationSchoolTerminationTimestamp"},
+			Controls:   []ldap.Control(nil),
+		}
+		lm.On("Search", schoolLookupAfterCreate).
+			Return(
+				&ldap.SearchResult{
+					Entries: []*ldap.Entry{schoolEntry},
+				},
+				nil)
+		b, err := getMockedBackend(lm, eduConfig, &logger)
+		assert.Nil(t, err)
+		assert.NotEqual(t, "", b.educationConfig.schoolObjectClass)
+
+		school := libregraph.NewEducationSchool()
+		school.SetDisplayName(tt.schoolName)
+		school.SetSchoolNumber(tt.schoolNumber)
+		school.SetId("abcd-defg")
+		res_school, err := b.CreateEducationSchool(context.Background(), *school)
+		if tt.expectedError == nil {
+			assert.Nil(t, err)
+			lm.AssertNumberOfCalls(t, "Add", 1)
+			assert.NotNil(t, res_school)
+			assert.Equal(t, res_school.GetDisplayName(), school.GetDisplayName())
+			assert.Equal(t, res_school.GetId(), school.GetId())
+			assert.Equal(t, res_school.GetSchoolNumber(), school.GetSchoolNumber())
+			assert.False(t, res_school.HasTerminationDate())
+		} else {
+			assert.Equal(t, err, tt.expectedError)
+			assert.Nil(t, res_school)
+		}
+	}
 }
 
 func TestUpdateEducationSchoolTerminationDate(t *testing.T) {
@@ -218,7 +310,7 @@ func TestUpdateEducationSchoolOperation(t *testing.T) {
 			SchoolNumber: &tt.schoolNumber,
 		}
 
-		operation := b.UpdateEducationSchoolOperation(schoolUpdate, currentSchool)
+		operation := b.updateEducationSchoolOperation(schoolUpdate, currentSchool)
 		assert.Equal(t, tt.expectedOperation, operation)
 	}
 }
@@ -285,7 +377,7 @@ func TestDeleteEducationSchool(t *testing.T) {
 		if tt.expectedItemNotFound {
 			lm.AssertNumberOfCalls(t, "Del", 0)
 			assert.NotNil(t, err)
-			assert.Equal(t, "itemNotFound", err.Error())
+			assert.Equal(t, "itemNotFound: not found", err.Error())
 		} else {
 			assert.Nil(t, err)
 		}
@@ -349,7 +441,7 @@ func TestGetEducationSchool(t *testing.T) {
 
 		if tt.expectedItemNotFound {
 			assert.NotNil(t, err)
-			assert.Equal(t, "itemNotFound", err.Error())
+			assert.Equal(t, "itemNotFound: not found", err.Error())
 		} else {
 			assert.Nil(t, err)
 			assert.Equal(t, "Test School", school.GetDisplayName())
@@ -502,7 +594,7 @@ func TestRemoveMemberFromEducationSchool(t *testing.T) {
 	err = b.RemoveUserFromEducationSchool(context.Background(), "abcd-defg", "does-not-exist")
 	lm.AssertNumberOfCalls(t, "Search", 2)
 	assert.NotNil(t, err)
-	assert.Equal(t, "itemNotFound", err.Error())
+	assert.Equal(t, "itemNotFound: not found", err.Error())
 	err = b.RemoveUserFromEducationSchool(context.Background(), "abcd-defg", "abcd-defg")
 	lm.AssertNumberOfCalls(t, "Search", 4)
 	lm.AssertNumberOfCalls(t, "Modify", 1)
@@ -613,7 +705,7 @@ func TestRemoveClassFromEducationSchool(t *testing.T) {
 	err = b.RemoveClassFromEducationSchool(context.Background(), "abcd-defg", "does-not-exist")
 	lm.AssertNumberOfCalls(t, "Search", 2)
 	assert.NotNil(t, err)
-	assert.Equal(t, "itemNotFound", err.Error())
+	assert.Equal(t, "itemNotFound: not found", err.Error())
 	err = b.RemoveClassFromEducationSchool(context.Background(), "abcd-defg", "abcd-defg")
 	lm.AssertNumberOfCalls(t, "Search", 4)
 	lm.AssertNumberOfCalls(t, "Modify", 1)
diff --git a/services/graph/pkg/identity/ldap_education_user_test.go b/services/graph/pkg/identity/ldap_education_user_test.go
index 8b0e9fff53f..763f27b4f37 100644
--- a/services/graph/pkg/identity/ldap_education_user_test.go
+++ b/services/graph/pkg/identity/ldap_education_user_test.go
@@ -139,7 +139,7 @@ func TestDeleteEducationUser(t *testing.T) {
 	lm.AssertNumberOfCalls(t, "Search", 2)
 	lm.AssertNumberOfCalls(t, "Del", 1)
 	assert.NotNil(t, err)
-	assert.Equal(t, "itemNotFound", err.Error())
+	assert.Equal(t, "itemNotFound: not found", err.Error())
 }
 
 func TestGetEducationUser(t *testing.T) {
@@ -157,7 +157,7 @@ func TestGetEducationUser(t *testing.T) {
 	_, err = b.GetEducationUser(context.Background(), "xxxx-xxxx")
 	lm.AssertNumberOfCalls(t, "Search", 2)
 	assert.NotNil(t, err)
-	assert.Equal(t, "itemNotFound", err.Error())
+	assert.Equal(t, "itemNotFound: not found", err.Error())
 }
 
 func TestGetEducationUsers(t *testing.T) {
diff --git a/services/graph/pkg/identity/ldap_group_test.go b/services/graph/pkg/identity/ldap_group_test.go
index e3613967b87..79431d4760f 100644
--- a/services/graph/pkg/identity/ldap_group_test.go
+++ b/services/graph/pkg/identity/ldap_group_test.go
@@ -59,34 +59,22 @@ func TestGetGroup(t *testing.T) {
 
 	b, _ := getMockedBackend(lm, lconfig, &logger)
 	_, err := b.GetGroup(context.Background(), "group", nil)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 	_, err = b.GetGroup(context.Background(), "group", queryParamExpand)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 	_, err = b.GetGroup(context.Background(), "group", queryParamSelect)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 
 	// Mock an empty Search Result
 	lm = &mocks.Client{}
 	lm.On("Search", mock.Anything).Return(&ldap.SearchResult{}, nil)
 	b, _ = getMockedBackend(lm, lconfig, &logger)
 	_, err = b.GetGroup(context.Background(), "group", nil)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 	_, err = b.GetGroup(context.Background(), "group", queryParamExpand)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 	_, err = b.GetGroup(context.Background(), "group", queryParamSelect)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 
 	// Mock an invalid Search Result
 	lm = &mocks.Client{}
@@ -95,17 +83,11 @@ func TestGetGroup(t *testing.T) {
 	}, nil)
 	b, _ = getMockedBackend(lm, lconfig, &logger)
 	g, err := b.GetGroup(context.Background(), "group", nil)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 	g, err = b.GetGroup(context.Background(), "group", queryParamExpand)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 	g, err = b.GetGroup(context.Background(), "group", queryParamSelect)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 
 	// Mock a valid	Search Result
 	lm = &mocks.Client{}
@@ -240,9 +222,7 @@ func TestGetGroups(t *testing.T) {
 	lm.On("Search", mock.Anything).Return(nil, ldap.NewError(ldap.LDAPResultOperationsError, errors.New("mock")))
 	b, _ := getMockedBackend(lm, lconfig, &logger)
 	_, err := b.GetGroups(context.Background(), url.Values{})
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 
 	lm = &mocks.Client{}
 	lm.On("Search", mock.Anything).Return(&ldap.SearchResult{}, nil)
diff --git a/services/graph/pkg/identity/ldap_test.go b/services/graph/pkg/identity/ldap_test.go
index fcd5a551ae9..908862f8197 100644
--- a/services/graph/pkg/identity/ldap_test.go
+++ b/services/graph/pkg/identity/ldap_test.go
@@ -205,14 +205,10 @@ func TestGetUser(t *testing.T) {
 	}
 
 	_, err = b.GetUser(context.Background(), "fred", odataReqDefault)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 
 	_, err = b.GetUser(context.Background(), "fred", odataReqExpand)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 
 	// Mock an empty Search Result
 	lm = &mocks.Client{}
@@ -221,14 +217,10 @@ func TestGetUser(t *testing.T) {
 			&ldap.SearchResult{}, nil)
 	b, _ = getMockedBackend(lm, lconfig, &logger)
 	_, err = b.GetUser(context.Background(), "fred", odataReqDefault)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 
 	_, err = b.GetUser(context.Background(), "fred", odataReqExpand)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 
 	// Mock a valid Search Result
 	lm = &mocks.Client{}
@@ -265,9 +257,7 @@ func TestGetUser(t *testing.T) {
 
 	b, _ = getMockedBackend(lm, lconfig, &logger)
 	_, err = b.GetUser(context.Background(), "invalid", nil)
-	if err == nil || err.Error() != "itemNotFound" {
-		t.Errorf("Expected 'itemNotFound' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "itemNotFound:")
 }
 
 func TestGetUsers(t *testing.T) {
@@ -283,9 +273,7 @@ func TestGetUsers(t *testing.T) {
 
 	b, _ := getMockedBackend(lm, lconfig, &logger)
 	_, err = b.GetUsers(context.Background(), odataReqDefault)
-	if err == nil || err.Error() != "generalException" {
-		t.Errorf("Expected 'generalException' got '%s'", err.Error())
-	}
+	assert.ErrorContains(t, err, "generalException:")
 
 	lm = &mocks.Client{}
 	lm.On("Search", mock.Anything).Return(&ldap.SearchResult{}, nil)