feat: introduce Cloudian GET User

internal/controller/group/group.go

@@ -154,10 +154,10 @@ func (c *external) Observe(ctx context.Context, mg resource.Managed) (managed.Ex
 	}
 
 	observedGroup, err := c.cloudianService.GetGroup(ctx, externalName)
+	if errors.Is(err, cloudian.ErrNotFound) {
+		return managed.ExternalObservation{ResourceExists: false}, nil
+	}
 	if err != nil {
-		if errors.Is(err, cloudian.ErrNotFound) {
-			return managed.ExternalObservation{ResourceExists: false}, nil
-		}
 		return managed.ExternalObservation{}, errors.Wrap(err, errGetGroup)
 	}
 

internal/controller/user/user.go

@@ -25,6 +25,7 @@ import (
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 
+	xpv1 "github.com/crossplane/crossplane-runtime/apis/common/v1"
 	"github.com/crossplane/crossplane-runtime/pkg/connection"
 	"github.com/crossplane/crossplane-runtime/pkg/controller"
 	"github.com/crossplane/crossplane-runtime/pkg/event"
@@ -48,7 +49,6 @@ const (
 	errNewClient  = "cannot create new Service"
 	errCreateUser = "cannot create User"
 	errDeleteUser = "cannot delete User"
-	errListUsers  = "cannot list Users"
 	errGetUser    = "cannot get User"
 )
 
@@ -157,40 +157,35 @@ func (c *external) Observe(ctx context.Context, mg resource.Managed) (managed.Ex
 		return managed.ExternalObservation{}, nil
 	}
 
-	// TODO: GET User instead of listing users for group
-	users, err := c.cloudianService.ListUsers(ctx, group, nil)
+	_, err := c.cloudianService.GetUser(ctx, cloudian.User{
+		GroupID: group,
+		UserID:  externalName})
+	if errors.Is(err, cloudian.ErrNotFound) {
+		return managed.ExternalObservation{ResourceExists: false}, nil
+	}
 	if err != nil {
-		return managed.ExternalObservation{}, errors.Wrap(err, errListUsers)
+		return managed.ExternalObservation{}, errors.Wrap(err, errGetUser)
 	}
 
-	upToDate := isUpToDate(meta.GetExternalName(mg), users)
+	cr.SetConditions(xpv1.Available())
 
 	return managed.ExternalObservation{
 		// Return false when the external resource does not exist. This lets
 		// the managed resource reconciler know that it needs to call Create to
 		// (re)create the resource, or that it has successfully been deleted.
-		ResourceExists: upToDate,
+		ResourceExists: true,
 
 		// Return false when the external resource exists, but it not up to date
 		// with the desired managed resource state. This lets the managed
 		// resource reconciler know that it needs to call Update.
-		ResourceUpToDate: upToDate,
+		ResourceUpToDate: true,
 
 		// Return any details that may be required to connect to the external
 		// resource. These will be stored as the connection secret.
 		ConnectionDetails: managed.ConnectionDetails{},
 	}, nil
 }
 
-func isUpToDate(userId string, users []cloudian.User) bool {
-	for _, user := range users {
-		if user.UserID == userId {
-			return true
-		}
-	}
-	return false
-}
-
 func (c *external) Create(ctx context.Context, mg resource.Managed) (managed.ExternalCreation, error) {
 	cr, ok := mg.(*v1alpha1.User)
 	if !ok {

internal/sdk/cloudian/sdk.go

@@ -206,6 +206,31 @@ func (client Client) CreateUser(ctx context.Context, user User) error {
 	}
 }
 
+// GetUser gets a user. Returns an error even in the case of a user not found.
+// This error can then be checked against ErrNotFound: errors.Is(err, ErrNotFound)
+func (client Client) GetUser(ctx context.Context, user User) (*User, error) {
+	// FIXME: Introduce UserId struct and enrich User
+	resp, err := client.newRequest(ctx).
+		SetQueryParams(map[string]string{
+			"groupId": user.GroupID,
+			"userId":  user.UserID,
+		}).
+		Get("/user")
+	if err != nil {
+		return nil, err
+	}
+
+	switch resp.StatusCode() {
+	case 200:
+		return &user, nil
+	case 204:
+		// Cloudian-API returns 204 if the user does not exist
+		return nil, ErrNotFound
+	default:
+		return nil, fmt.Errorf("error: GET user unexpected status code: %d", resp.StatusCode())
+	}
+}
+
 // CreateUserCredentials creates a new set of credentials for a user.
 func (client Client) CreateUserCredentials(ctx context.Context, user User) (*SecurityInfo, error) {
 	var securityInfo SecurityInfo
@@ -376,7 +401,7 @@ func (client Client) GetGroup(ctx context.Context, groupID string) (*Group, erro
 		// Cloudian-API returns 204 if the group does not exist
 		return nil, ErrNotFound
 	default:
-		return nil, fmt.Errorf("GET unexpected status. Failure: %w", err)
+		return nil, fmt.Errorf("error: GET group unexpected status code: %d", resp.StatusCode())
 	}
 }
 

internal/sdk/cloudian/sdk_test.go

@@ -154,3 +154,31 @@ func mockBy(handler http.HandlerFunc) (*Client, *httptest.Server) {
 	mockServer := httptest.NewServer(handler)
 	return NewClient(mockServer.URL, ""), mockServer
 }
+
+func TestClient_GetUser(t *testing.T) {
+	tests := []struct {
+		name    string
+		user    User
+		status  int
+		wantErr error
+	}{
+		{name: "Exists", user: User{UserID: strconv.Itoa(http.StatusOK)}},
+		{name: "Not found", user: User{UserID: strconv.Itoa(http.StatusNoContent)}, wantErr: ErrNotFound},
+	}
+
+	client, testServer := mockBy(func(w http.ResponseWriter, r *http.Request) {
+		userId := r.URL.Query().Get("userId")
+		statusCode, _ := strconv.Atoi(userId)
+		w.WriteHeader(statusCode)
+	})
+	defer testServer.Close()
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := client.GetUser(context.Background(), tt.user)
+			if !errors.Is(err, tt.wantErr) {
+				t.Errorf("GetUser() error = %v, wantErr %v", err, tt.wantErr)
+			}
+		})
+	}
+}