Fix logs tail issue when there are no logs (#744)

internal/cli/logs.go

@@ -9,6 +9,11 @@ import (
 	"github.com/spf13/cobra"
 )
 
+// Besides the limitation of 100 log events per request to retrieve logs,
+// we may only paginate through up to 1000 search results.
+// https://auth0.com/docs/logs/retrieve-log-events-using-mgmt-api#limitations
+const logsPerPageLimit = 100
+
 var (
 	logsFilter = Flag{
 		Name:      "Filter",
@@ -63,7 +68,7 @@ func listLogsCmd(cli *cli) *cobra.Command {
 		RunE: func(cmd *cobra.Command, args []string) error {
 			list, err := getLatestLogs(cli, inputs.Num, inputs.Filter)
 			if err != nil {
-				return fmt.Errorf("An unexpected error occurred while getting logs: %v", err)
+				return fmt.Errorf("failed to get logs: %w", err)
 			}
 
 			hasFilter := inputs.Filter != ""
@@ -100,45 +105,43 @@ func tailLogsCmd(cli *cli) *cobra.Command {
   auth0 logs tail --filter "type:f" # See the full list of type codes at https://auth0.com/docs/logs/log-event-type-codes
   auth0 logs tail -n 100`,
 		RunE: func(cmd *cobra.Command, args []string) error {
-			lastLogID := ""
 			list, err := getLatestLogs(cli, inputs.Num, inputs.Filter)
 			if err != nil {
-				return fmt.Errorf("An unexpected error occurred while getting logs: %v", err)
+				return fmt.Errorf("failed to get logs: %w", err)
 			}
 
-			// TODO(cyx): This is a hack for now to make the
-			// streaming work faster.
-			//
-			// Create a `set` to detect duplicates clientside.
-			set := make(map[string]struct{})
-			list = dedupeLogs(list, set)
+			logsCh := make(chan []*management.Log)
 
+			var lastLogID string
 			if len(list) > 0 {
 				lastLogID = list[len(list)-1].GetLogID()
 			}
 
-			logsCh := make(chan []*management.Log)
+			// Create a `set` to detect duplicates clientside.
+			set := make(map[string]struct{})
+			list = dedupeLogs(list, set)
 
-			go func() {
-				// This is pretty important and allows
-				// us to close / terminate the command.
+			go func(lastLogID string) {
 				defer close(logsCh)
 
 				for {
 					queryParams := []management.RequestOption{
-						management.Query(fmt.Sprintf("log_id:[%s TO *]", lastLogID)),
 						management.Parameter("page", "0"),
 						management.Parameter("per_page", "100"),
 						management.Parameter("sort", "date:-1"),
 					}
 
+					if lastLogID != "" {
+						queryParams = append(queryParams, management.Query(fmt.Sprintf("log_id:[%s TO *]", lastLogID)))
+					}
+
 					if inputs.Filter != "" {
 						queryParams = append(queryParams, management.Query(inputs.Filter))
 					}
 
-					list, err = cli.api.Log.List(queryParams...)
+					list, err := cli.api.Log.List(queryParams...)
 					if err != nil {
-						cli.renderer.Errorf("An unexpected error occurred while getting logs: %v", err)
+						cli.renderer.Errorf("Failed to get latest logs: %v", err)
 						return
 					}
 
@@ -147,12 +150,12 @@ func tailLogsCmd(cli *cli) *cobra.Command {
 						lastLogID = list[len(list)-1].GetLogID()
 					}
 
-					if len(list) < 90 {
-						// Not a lot is happening, sleep on it
-						time.Sleep(1 * time.Second)
+					if len(list) < logsPerPageLimit {
+						// Not a lot is happening, sleep on it.
+						time.Sleep(time.Second)
 					}
 				}
-			}()
+			}(lastLogID)
 
 			cli.renderer.LogTail(list, logsCh, !cli.debug)
 			return nil
@@ -168,11 +171,8 @@ func tailLogsCmd(cli *cli) *cobra.Command {
 func getLatestLogs(cli *cli, n int, filter string) ([]*management.Log, error) {
 	page := 0
 	perPage := n
-
-	if perPage > 1000 {
-		// Pagination max out at 1000 entries in total
-		// https://auth0.com/docs/logs/retrieve-log-events-using-mgmt-api#limitations
-		perPage = 1000
+	if perPage > logsPerPageLimit {
+		perPage = logsPerPageLimit
 	}
 
 	queryParams := []management.RequestOption{

internal/cli/logs_test.go

@@ -1,16 +1,109 @@
 package cli
 
 import (
+	"bytes"
+	"fmt"
 	"testing"
 	"time"
 
 	"github.com/auth0/go-auth0/management"
+	"github.com/golang/mock/gomock"
 
 	"github.com/stretchr/testify/assert"
 
 	"github.com/auth0/auth0-cli/internal/auth0"
+	"github.com/auth0/auth0-cli/internal/auth0/mock"
+	"github.com/auth0/auth0-cli/internal/display"
 )
 
+func TestTailLogsCommand(t *testing.T) {
+	t.Run("it returns an error when it fails to get the logs on the first request", func(t *testing.T) {
+		ctrl := gomock.NewController(t)
+		defer ctrl.Finish()
+
+		logsAPI := mock.NewMockLogAPI(ctrl)
+		logsAPI.EXPECT().
+			List(gomock.Any()).
+			Return(nil, fmt.Errorf("generic error"))
+
+		cli := &cli{
+			api: &auth0.API{Log: logsAPI},
+		}
+
+		cmd := tailLogsCmd(cli)
+		cmd.SetArgs([]string{"--number", "90", "--filter", "user_id:123"})
+		err := cmd.Execute()
+
+		assert.EqualError(t, err, "failed to get logs: generic error")
+	})
+
+	t.Run("it returns an error when it fails to get the logs on the 3rd request", func(t *testing.T) {
+		ctrl := gomock.NewController(t)
+		defer ctrl.Finish()
+
+		logsAPI := mock.NewMockLogAPI(ctrl)
+		logsAPI.EXPECT().
+			List(gomock.Any()).
+			Return(
+				[]*management.Log{
+					{
+						LogID:       auth0.String("354234"),
+						Type:        auth0.String("sapi"),
+						Description: auth0.String("Update branding settings"),
+					},
+				},
+				nil,
+			)
+
+		logsAPI.EXPECT().
+			List(gomock.Any()).
+			Return(
+				[]*management.Log{
+					{
+						LogID:       auth0.String("354234"),
+						Type:        auth0.String("sapi"),
+						Description: auth0.String("Update branding settings"),
+					},
+					{
+						LogID:       auth0.String("354236"),
+						Type:        auth0.String("sapi"),
+						Description: auth0.String("Update tenant settings"),
+					},
+				},
+				nil,
+			)
+
+		logsAPI.EXPECT().
+			List(gomock.Any()).
+			Return(nil, fmt.Errorf("generic error"))
+
+		expectedResult := `TYPE                       DESCRIPTION                                               DATE                    CONNECTION              CLIENT                  
+API Operation              Update branding settings                                  Jan 01 00:00:00.000     N/A                     N/A    
+`
+
+		message := &bytes.Buffer{}
+		result := &bytes.Buffer{}
+		cli := &cli{
+			renderer: &display.Renderer{
+				Tenant:        "auth0-cli-tests.eu.auth0.com",
+				MessageWriter: message,
+				ResultWriter:  result,
+			},
+			api: &auth0.API{Log: logsAPI},
+		}
+
+		cmd := tailLogsCmd(cli)
+		cmd.SetArgs([]string{"--number", "90", "--filter", "user_id:123"})
+		err := cmd.Execute()
+		assert.NoError(t, err)
+
+		assert.Contains(t, message.String(), "auth0-cli-tests.eu.auth0.com") // Ensure we display the tenant name.
+		assert.Contains(t, message.String(), "logs")                         // Ensure header is set in output.
+		assert.Contains(t, message.String(), "Failed to get latest logs: generic error")
+		assert.Equal(t, expectedResult, result.String())
+	})
+}
+
 func TestDedupeLogs(t *testing.T) {
 	t.Run("removes duplicate logs and sorts by date asc", func(t *testing.T) {
 		logs := []*management.Log{