Separate printing logs and getting logs concerns (closes nanovms#657)

* Add safeguards to azure getIstances

* Add safeguard to openstack getInstances

cmd/instance.go

@@ -274,7 +274,7 @@ func instanceLogsCommandHandler(cmd *cobra.Command, args []string) {
 	c.CloudConfig.ProjectID = projectID
 	c.CloudConfig.Zone = zone
 	ctx := api.NewContext(&c, &p)
-	err = p.GetInstanceLogs(ctx, args[0], watch)
+	err = p.PrintInstanceLogs(ctx, args[0], watch)
 	if err != nil {
 		exitWithError(err.Error())
 	}

lepton/aws.go

@@ -672,8 +672,18 @@ func (p *AWS) DeleteInstance(ctx *Context, instancename string) error {
 	return nil
 }
 
+// PrintInstanceLogs writes instance logs to console
+func (p *AWS) PrintInstanceLogs(ctx *Context, instancename string, watch bool) error {
+	l, err := p.GetInstanceLogs(ctx, instancename)
+	if err != nil {
+		return err
+	}
+	fmt.Printf(l)
+	return nil
+}
+
 // GetInstanceLogs gets instance related logs
-func (p *AWS) GetInstanceLogs(ctx *Context, instancename string, watch bool) error {
+func (p *AWS) GetInstanceLogs(ctx *Context, instancename string) (string, error) {
 	svc, err := session.NewSession(&aws.Config{
 		Region: aws.String(ctx.config.CloudConfig.Zone)},
 	)
@@ -695,18 +705,17 @@ func (p *AWS) GetInstanceLogs(ctx *Context, instancename string, watch bool) err
 		} else {
 			fmt.Println(err.Error())
 		}
-		return err
+		return "", err
 	}
 
 	data, err := base64.StdEncoding.DecodeString(aws.StringValue(result.Output))
 	if err != nil {
-		return err
+		return "", err
 	}
 
 	l := string(data)
-	fmt.Printf(l)
 
-	return nil
+	return l, nil
 }
 
 func (p *AWS) customizeImage(ctx *Context) (string, error) {

lepton/azure.go

@@ -538,28 +538,32 @@ func (a *Azure) GetInstances(ctx *Context) ([]CloudInstance, error) {
 		privateIP := ""
 		publicIP := ""
 
-		nifs := *((*(*instance.VirtualMachineProperties).NetworkProfile).NetworkInterfaces)
+		if instance.VirtualMachineProperties != nil {
+			nifs := *((*(*instance.VirtualMachineProperties).NetworkProfile).NetworkInterfaces)
 
-		for i := 0; i < len(nifs); i++ {
-			nicClient := a.getNicClient()
-			nic, err := nicClient.Get(context.TODO(), a.groupName, cinstance.Name, "")
-			if err != nil {
-				fmt.Println(err)
-			}
-
-			ipconfig := *(*nic.InterfacePropertiesFormat).IPConfigurations
-			for x := 0; x < len(ipconfig); x++ {
-				format := *ipconfig[x].InterfaceIPConfigurationPropertiesFormat
-				privateIP = *format.PrivateIPAddress
-
-				ipClient := a.getIPClient()
-				pubip, err := ipClient.Get(context.TODO(), a.groupName, cinstance.Name, "")
+			for i := 0; i < len(nifs); i++ {
+				nicClient := a.getNicClient()
+				nic, err := nicClient.Get(context.TODO(), a.groupName, cinstance.Name, "")
 				if err != nil {
 					fmt.Println(err)
 				}
-				publicIP = *(*pubip.PublicIPAddressPropertiesFormat).IPAddress
-			}
 
+				if nic.InterfacePropertiesFormat != nil {
+					ipconfig := *(*nic.InterfacePropertiesFormat).IPConfigurations
+					for x := 0; x < len(ipconfig); x++ {
+						format := *ipconfig[x].InterfaceIPConfigurationPropertiesFormat
+						privateIP = *format.PrivateIPAddress
+
+						ipClient := a.getIPClient()
+						pubip, err := ipClient.Get(context.TODO(), a.groupName, cinstance.Name, "")
+						if err != nil {
+							fmt.Println(err)
+						}
+						publicIP = *(*pubip.PublicIPAddressPropertiesFormat).IPAddress
+					}
+				}
+
+			}
 		}
 		cinstance.PrivateIps = []string{privateIP}
 		cinstance.PublicIps = []string{publicIP}
@@ -651,8 +655,18 @@ func (a *Azure) StopInstance(ctx *Context, instancename string) error {
 	return nil
 }
 
+// PrintInstanceLogs writes instance logs to console
+func (a *Azure) PrintInstanceLogs(ctx *Context, instancename string, watch bool) error {
+	l, err := a.GetInstanceLogs(ctx, instancename)
+	if err != nil {
+		return err
+	}
+	fmt.Printf(l)
+	return nil
+}
+
 // GetInstanceLogs gets instance related logs
-func (a *Azure) GetInstanceLogs(ctx *Context, instancename string, watch bool) error {
+func (a *Azure) GetInstanceLogs(ctx *Context, instancename string) (string, error) {
 	// this is basically 2 calls
 	// 1) grab the log location
 	// 2) grab it from storage
@@ -700,17 +714,15 @@ func (a *Azure) GetInstanceLogs(ctx *Context, instancename string, watch bool) e
 
 	get, err := blobURL.Download(context.TODO(), 0, 0, azblob.BlobAccessConditions{}, false)
 	if err != nil {
-		fmt.Println(err)
+		return "", err
 	}
 
 	downloadedData := &bytes.Buffer{}
 	reader := get.Body(azblob.RetryReaderOptions{})
 	downloadedData.ReadFrom(reader)
 	reader.Close()
 
-	fmt.Println(downloadedData.String())
-
-	return nil
+	return downloadedData.String(), nil
 }
 
 // ResizeImage is not supported on azure.

lepton/digital_ocean.go

@@ -173,11 +173,21 @@ func (do *DigitalOcean) StopInstance(ctx *Context, instancename string) error {
 	return nil
 }
 
-// GetInstanceLogs gets instance related logs
-func (do *DigitalOcean) GetInstanceLogs(ctx *Context, instancename string, watch bool) error {
+// PrintInstanceLogs writes instance logs to console
+func (do *DigitalOcean) PrintInstanceLogs(ctx *Context, instancename string, watch bool) error {
+	l, err := do.GetInstanceLogs(ctx, instancename)
+	if err != nil {
+		return err
+	}
+	fmt.Printf(l)
 	return nil
 }
 
+// GetInstanceLogs gets instance related logs
+func (do *DigitalOcean) GetInstanceLogs(ctx *Context, instancename string) (string, error) {
+	return "", nil
+}
+
 func (do *DigitalOcean) customizeImage(ctx *Context) (string, error) {
 	imagePath := ctx.config.RunConfig.Imagename
 	return imagePath, nil

lepton/gcp.go

@@ -556,27 +556,35 @@ func (p *GCloud) StopInstance(ctx *Context, instancename string) error {
 	return nil
 }
 
+// PrintInstanceLogs writes instance logs to console
+func (p *GCloud) PrintInstanceLogs(ctx *Context, instancename string, watch bool) error {
+	l, err := p.GetInstanceLogs(ctx, instancename)
+	if err != nil {
+		return err
+	}
+	fmt.Printf(l)
+	return nil
+}
+
 // GetInstanceLogs gets instance related logs
-func (p *GCloud) GetInstanceLogs(ctx *Context, instancename string, watch bool) error {
+func (p *GCloud) GetInstanceLogs(ctx *Context, instancename string) (string, error) {
 	context := context.TODO()
 
 	cloudConfig := ctx.config.CloudConfig
 	lastPos := int64(0)
-	for {
-		resp, err := p.Service.Instances.GetSerialPortOutput(cloudConfig.ProjectID, cloudConfig.Zone, instancename).Start(lastPos).Context(context).Do()
-		if err != nil {
-			return err
-		}
-		if resp.Contents != "" {
-			fmt.Printf("%s", resp.Contents)
-		}
-		if lastPos == resp.Next && !watch {
-			break
-		}
-		lastPos = resp.Next
-		time.Sleep(time.Second)
+
+	resp, err := p.Service.Instances.GetSerialPortOutput(cloudConfig.ProjectID, cloudConfig.Zone, instancename).Start(lastPos).Context(context).Do()
+	if err != nil {
+		return "", err
 	}
-	return nil
+	if resp.Contents != "" {
+		return resp.Contents, nil
+	}
+
+	lastPos = resp.Next
+	time.Sleep(time.Second)
+
+	return "", nil
 }
 
 func createArchive(archive string, files []string) error {

lepton/onprem.go

@@ -261,18 +261,26 @@ func (p *OnPrem) DeleteInstance(ctx *Context, instancename string) error {
 	return nil
 }
 
+// PrintInstanceLogs writes instance logs to console
+func (p *OnPrem) PrintInstanceLogs(ctx *Context, instancename string, watch bool) error {
+	l, err := p.GetInstanceLogs(ctx, instancename)
+	if err != nil {
+		return err
+	}
+	fmt.Printf(l)
+	return nil
+}
+
 // GetInstanceLogs for onprem instance logs
-func (p *OnPrem) GetInstanceLogs(ctx *Context, instancename string, watch bool) error {
+func (p *OnPrem) GetInstanceLogs(ctx *Context, instancename string) (string, error) {
 
 	body, err := ioutil.ReadFile("/tmp/" + instancename + ".log")
 	if err != nil {
 		fmt.Println(err)
 		os.Exit(1)
 	}
 
-	fmt.Println(string(body))
-
-	return nil
+	return string(body), nil
 }
 
 // Initialize on prem provider

lepton/openstack.go

@@ -3,13 +3,15 @@ package lepton
 import (
 	"errors"
 	"fmt"
-	"github.com/gophercloud/gophercloud/openstack/compute/v2/extensions/bootfromvolume"
-	"github.com/olekukonko/tablewriter"
 	"os"
 	"strconv"
 	"strings"
 	"time"
 
+	"github.com/olekukonko/tablewriter"
+
+	"github.com/gophercloud/gophercloud/openstack/compute/v2/extensions/bootfromvolume"
+
 	"github.com/gophercloud/gophercloud/openstack/compute/v2/flavors"
 
 	"github.com/gophercloud/gophercloud"
@@ -545,32 +547,40 @@ func (o *OpenStack) findInstance(name string) (id string, err error) {
 	return sid, errors.New("could not find server")
 }
 
+// PrintInstanceLogs writes instance logs to console
+func (o *OpenStack) PrintInstanceLogs(ctx *Context, instancename string, watch bool) error {
+	l, err := o.GetInstanceLogs(ctx, instancename)
+	if err != nil {
+		return err
+	}
+	fmt.Printf(l)
+	return nil
+}
+
 // GetInstanceLogs gets instance related logs.
-func (o *OpenStack) GetInstanceLogs(ctx *Context, instancename string, watch bool) error {
+func (o *OpenStack) GetInstanceLogs(ctx *Context, instancename string) (string, error) {
 
 	client, err := openstack.NewComputeV2(o.provider, gophercloud.EndpointOpts{
 		Region: os.Getenv("OS_REGION_NAME"),
 	})
 	if err != nil {
-		fmt.Println(err)
+		return "", err
 	}
 
 	sid, err := o.findInstance(instancename)
 	if err != nil {
-		fmt.Println(err)
+		return "", err
 	}
 
 	outputOpts := &servers.ShowConsoleOutputOpts{
 		Length: 100,
 	}
 	output, err := servers.ShowConsoleOutput(client, sid, outputOpts).Extract()
 	if err != nil {
-		fmt.Println(err)
+		return "", err
 	}
 
-	fmt.Println(output)
-
-	return nil
+	return output, nil
 }
 
 func (o *OpenStack) customizeImage(ctx *Context) (string, error) {

lepton/provider.go

@@ -20,7 +20,8 @@ type Provider interface {
 	DeleteInstance(ctx *Context, instancename string) error
 	StopInstance(ctx *Context, instancename string) error
 	StartInstance(ctx *Context, instancename string) error
-	GetInstanceLogs(ctx *Context, instancename string, watch bool) error
+	GetInstanceLogs(ctx *Context, instancename string) (string, error)
+	PrintInstanceLogs(ctx *Context, instancename string, watch bool) error
 
 	VolumeService
 

lepton/vsphere.go

@@ -1,6 +1,7 @@
 package lepton
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"io"
@@ -746,42 +747,44 @@ func (v *Vsphere) StopInstance(ctx *Context, instancename string) error {
 	return err
 }
 
+// PrintInstanceLogs writes instance logs to console
+func (v *Vsphere) PrintInstanceLogs(ctx *Context, instancename string, watch bool) error {
+	l, err := v.GetInstanceLogs(ctx, instancename)
+	if err != nil {
+		return err
+	}
+	fmt.Printf(l)
+	return nil
+}
+
 // GetInstanceLogs gets instance related logs.
 // govc datastore.tail -n 100 gtest/serial.out
 // logs don't appear until you spin up the instance.
-func (v *Vsphere) GetInstanceLogs(ctx *Context, instancename string, watch bool) error {
-
+func (v *Vsphere) GetInstanceLogs(ctx *Context, instancename string) (string, error) {
 	f := find.NewFinder(v.client, true)
 	ds, err := f.DatastoreOrDefault(context.TODO(), v.datastore)
 	if err != nil {
-		fmt.Println(err)
-		return err
-	}
-
-	_, err = f.DefaultHostSystem(context.TODO())
-	if err != nil {
-		fmt.Println(err)
+		return "", err
 	}
 
 	serialFile := instancename + "/console.log"
-
 	file, err := ds.Open(context.TODO(), serialFile)
 	if err != nil {
-		return err
+		return "", err
 	}
-
 	var reader io.ReadCloser = file
 
 	err = file.Tail(100)
 	if err != nil {
-		return err
+		return "", err
 	}
 
-	_, err = io.Copy(os.Stdout, reader)
+	buf := new(bytes.Buffer)
+	_, err = io.Copy(buf, reader)
 
 	_ = reader.Close()
 
-	return nil
+	return buf.String(), nil
 }
 
 func (v *Vsphere) customizeImage(ctx *Context) (string, error) {