Add --tail flag to support tailing live application logs (#1004)

Author: ZachEddy

args.go

@@ -44,6 +44,8 @@ const (
 	ArgAppDeployment = "deployment"
 	// ArgAppLogFollow follow logs.
 	ArgAppLogFollow = "follow"
+	// ArgAppLogTail tail logs.
+	ArgAppLogTail = "tail"
 	// ArgAppForceRebuild forces a deployment rebuild
 	ArgAppForceRebuild = "force-rebuild"
 	// ArgClusterName is a cluster name argument.

commands/apps.go

@@ -170,6 +170,7 @@ Three types of logs are supported and can be configured with --`+doctl.ArgAppLog
 	AddStringFlag(logs, doctl.ArgAppDeployment, "", "", "The deployment ID. Defaults to current deployment.")
 	AddStringFlag(logs, doctl.ArgAppLogType, "", strings.ToLower(string(godo.AppLogTypeRun)), "The type of logs.")
 	AddBoolFlag(logs, doctl.ArgAppLogFollow, "f", false, "Follow logs as they are emitted.")
+	AddIntFlag(logs, doctl.ArgAppLogTail, "", -1, "Number of lines to show from the end of the log.")
 
 	CmdBuilder(
 		cmd,
@@ -496,8 +497,12 @@ func RunAppsGetLogs(c *CmdConfig) error {
 	if err != nil {
 		return err
 	}
+	logTail, err := c.Doit.GetInt(c.NS, doctl.ArgAppLogTail)
+	if err != nil {
+		return err
+	}
 
-	logs, err := c.Apps().GetLogs(appID, deploymentID, component, logType, logFollow)
+	logs, err := c.Apps().GetLogs(appID, deploymentID, component, logType, logFollow, logTail)
 	if err != nil {
 		return err
 	}

commands/apps_test.go

@@ -379,7 +379,7 @@ func TestRunAppsGetLogs(t *testing.T) {
 
 	for typeStr, logType := range types {
 		withTestClient(t, func(config *CmdConfig, tm *tcMocks) {
-			tm.apps.EXPECT().GetLogs(appID, deploymentID, component, logType, true).Times(1).Return(&godo.AppLogs{LiveURL: "https://proxy-apps-prod-ams3-001.ondigitalocean.app/?token=aa-bb-11-cc-33"}, nil)
+			tm.apps.EXPECT().GetLogs(appID, deploymentID, component, logType, true, 1).Times(1).Return(&godo.AppLogs{LiveURL: "https://proxy-apps-prod-ams3-001.ondigitalocean.app/?token=aa-bb-11-cc-33"}, nil)
 			tm.listen.EXPECT().Start().Times(1).Return(nil)
 
 			tc := config.Doit.(*doctl.TestConfig)
@@ -393,6 +393,7 @@ func TestRunAppsGetLogs(t *testing.T) {
 			config.Doit.Set(config.NS, doctl.ArgAppDeployment, deploymentID)
 			config.Doit.Set(config.NS, doctl.ArgAppLogType, typeStr)
 			config.Doit.Set(config.NS, doctl.ArgAppLogFollow, true)
+			config.Doit.Set(config.NS, doctl.ArgAppLogTail, 1)
 
 			err := RunAppsGetLogs(config)
 			require.NoError(t, err)

do/apps.go

@@ -32,7 +32,7 @@ type AppsService interface {
 	GetDeployment(appID, deploymentID string) (*godo.Deployment, error)
 	ListDeployments(appID string) ([]*godo.Deployment, error)
 
-	GetLogs(appID, deploymentID, component string, logType godo.AppLogType, follow bool) (*godo.AppLogs, error)
+	GetLogs(appID, deploymentID, component string, logType godo.AppLogType, follow bool, tail int) (*godo.AppLogs, error)
 
 	ListRegions() ([]*godo.AppRegion, error)
 
@@ -171,8 +171,8 @@ func (s *appsService) ListDeployments(appID string) ([]*godo.Deployment, error)
 	return list, nil
 }
 
-func (s *appsService) GetLogs(appID, deploymentID, component string, logType godo.AppLogType, follow bool) (*godo.AppLogs, error) {
-	logs, _, err := s.client.Apps.GetLogs(s.ctx, appID, deploymentID, component, logType, follow)
+func (s *appsService) GetLogs(appID, deploymentID, component string, logType godo.AppLogType, follow bool, tail int) (*godo.AppLogs, error) {
+	logs, _, err := s.client.Apps.GetLogs(s.ctx, appID, deploymentID, component, logType, follow, tail)
 	if err != nil {
 		return nil, err
 	}

do/mocks/AppsService.go

@@ -8,7 +8,7 @@ require (
 	github.com/containerd/continuity v0.0.0-20200413184840-d3ef23f19fbb // indirect
 	github.com/cpuguy83/go-md2man v1.0.10 // indirect
 	github.com/creack/pty v1.1.11
-	github.com/digitalocean/godo v1.61.0
+	github.com/digitalocean/godo v1.63.0
 	github.com/docker/cli v0.0.0-20200622130859-87db43814b48
 	github.com/docker/docker v17.12.0-ce-rc1.0.20200531234253-77e06fda0c94+incompatible // indirect
 	github.com/docker/docker-credential-helpers v0.6.3 // indirect

go.mod

@@ -145,6 +145,8 @@ github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954 h1:RMLoZVzv4GliuW
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
 github.com/digitalocean/godo v1.61.0 h1:PChvUn5+Ajwvl7caOJoFbcM9r+y91ssQbM0W0k3pnZU=
 github.com/digitalocean/godo v1.61.0/go.mod h1:p7dOjjtSBqCTUksqtA5Fd3uaKs9kyTq2xcz76ulEJRU=
+github.com/digitalocean/godo v1.63.0 h1:WN/mv8M1DGKQ58VwnD9PjIyULpo1TZGYhoNhvEtBREk=
+github.com/digitalocean/godo v1.63.0/go.mod h1:p7dOjjtSBqCTUksqtA5Fd3uaKs9kyTq2xcz76ulEJRU=
 github.com/docker/cli v0.0.0-20200622130859-87db43814b48 h1:AC8qbhi/SjYf4iN2W3jSsofZGHWPjG8pjf5P143KUM8=
 github.com/docker/cli v0.0.0-20200622130859-87db43814b48/go.mod h1:JLrzqnKDaYBop7H2jaqPtU4hHvMKP+vjCwu2uszcLI8=
 github.com/docker/docker v17.12.0-ce-rc1.0.20200531234253-77e06fda0c94+incompatible h1:PmGHHCZ43l6h8aZIi+Xa+z1SWe4dFImd5EK3TNp1jlo=

go.sum

@@ -879,6 +879,7 @@ var _ = suite("apps/get-logs", func(t *testing.T, when spec.G, it spec.S) {
 			"service",
 			"--deployment="+testDeploymentUUID,
 			"--type=run",
+			"--tail=1",
 			"-f",
 		)