Add support for go-getter modes

Fixes #2678

api/tasks.go

@@ -2,6 +2,9 @@ package api
 
 import (
 	"fmt"
+	"path"
+
+	"path/filepath"
 	"strings"
 	"time"
 
@@ -323,12 +326,30 @@ func (t *Task) Canonicalize(tg *TaskGroup, job *Job) {
 type TaskArtifact struct {
 	GetterSource  *string           `mapstructure:"source"`
 	GetterOptions map[string]string `mapstructure:"options"`
+	GetterMode    *string           `mapstructure:"mode"`
 	RelativeDest  *string           `mapstructure:"destination"`
 }
 
 func (a *TaskArtifact) Canonicalize() {
+	if a.GetterMode == nil {
+		a.GetterMode = helper.StringToPtr("any")
+	}
+	if a.GetterSource == nil {
+		// Shouldn't be possible, but we don't want to panic
+		a.GetterSource = helper.StringToPtr("")
+	}
 	if a.RelativeDest == nil {
-		a.RelativeDest = helper.StringToPtr("local/")
+		switch *a.GetterMode {
+		case "file":
+			// File mode should default to local/filename
+			dest := *a.GetterSource
+			dest = path.Base(dest)
+			dest = filepath.Join("local", dest)
+			a.RelativeDest = &dest
+		default:
+			// Default to a directory
+			a.RelativeDest = helper.StringToPtr("local/")
+		}
 	}
 }
 

api/tasks_test.go

@@ -219,3 +219,17 @@ func TestTask_Constrain(t *testing.T) {
 		t.Fatalf("expect: %#v, got: %#v", expect, task.Constraints)
 	}
 }
+
+func TestTask_Artifact(t *testing.T) {
+	a := TaskArtifact{
+		GetterSource: helper.StringToPtr("http://localhost/foo.txt"),
+		GetterMode:   helper.StringToPtr("file"),
+	}
+	a.Canonicalize()
+	if *a.GetterMode != "file" {
+		t.Errorf("expected file but found %q", *a.GetterMode)
+	}
+	if *a.RelativeDest != "local/foo.txt" {
+		t.Errorf("expected local/foo.txt but found %q", *a.RelativeDest)
+	}
+}

client/getter/getter.go

@@ -33,7 +33,7 @@ type EnvReplacer interface {
 }
 
 // getClient returns a client that is suitable for Nomad downloading artifacts.
-func getClient(src, dst string) *gg.Client {
+func getClient(src string, mode gg.ClientMode, dst string) *gg.Client {
 	lock.Lock()
 	defer lock.Unlock()
 
@@ -50,7 +50,7 @@ func getClient(src, dst string) *gg.Client {
 	return &gg.Client{
 		Src:     src,
 		Dst:     dst,
-		Mode:    gg.ClientModeAny,
+		Mode:    mode,
 		Getters: getters,
 	}
 }
@@ -97,7 +97,17 @@ func GetArtifact(taskEnv EnvReplacer, artifact *structs.TaskArtifact, taskDir st
 
 	// Download the artifact
 	dest := filepath.Join(taskDir, artifact.RelativeDest)
-	if err := getClient(url, dest).Get(); err != nil {
+
+	// Convert from string getter mode to go-getter const
+	mode := gg.ClientModeAny
+	switch artifact.GetterMode {
+	case structs.GetterModeFile:
+		mode = gg.ClientModeFile
+	case structs.GetterModeDir:
+		mode = gg.ClientModeDir
+	}
+
+	if err := getClient(url, mode, dest).Get(); err != nil {
 		return newGetError(url, err, true)
 	}
 

command/agent/job_endpoint.go

@@ -654,6 +654,7 @@ func ApiTaskToStructsTask(apiTask *api.Task, structsTask *structs.Task) {
 			structsTask.Artifacts[k] = &structs.TaskArtifact{
 				GetterSource:  *ta.GetterSource,
 				GetterOptions: ta.GetterOptions,
+				GetterMode:    *ta.GetterMode,
 				RelativeDest:  *ta.RelativeDest,
 			}
 		}

jobspec/parse.go

@@ -788,6 +788,7 @@ func parseArtifacts(result *[]*api.TaskArtifact, list *ast.ObjectList) error {
 		valid := []string{
 			"source",
 			"options",
+			"mode",
 			"destination",
 		}
 		if err := checkHCLKeys(o.Val, valid); err != nil {

jobspec/parse_test.go

@@ -166,6 +166,7 @@ func TestParse(t *testing.T) {
 										GetterOptions: map[string]string{
 											"checksum": "md5:ff1cc0d3432dad54d607c1505fb7245c",
 										},
+										GetterMode: helper.StringToPtr("file"),
 									},
 								},
 								Vault: &api.Vault{

jobspec/test-fixtures/basic.hcl

@@ -140,6 +140,7 @@ job "binstore-storagelocker" {
       artifact {
         source = "http://bar.com/artifact"
         destination = "test/foo/"
+        mode = "file"
 
         options {
           checksum = "md5:ff1cc0d3432dad54d607c1505fb7245c"

nomad/structs/diff_test.go

@@ -2469,6 +2469,7 @@ func TestTaskDiff(t *testing.T) {
 						GetterOptions: map[string]string{
 							"bar": "baz",
 						},
+						GetterMode:   "dir",
 						RelativeDest: "bar",
 					},
 				},
@@ -2487,6 +2488,7 @@ func TestTaskDiff(t *testing.T) {
 						GetterOptions: map[string]string{
 							"bam": "baz",
 						},
+						GetterMode:   "file",
 						RelativeDest: "bam",
 					},
 				},
@@ -2498,6 +2500,12 @@ func TestTaskDiff(t *testing.T) {
 						Type: DiffTypeAdded,
 						Name: "Artifact",
 						Fields: []*FieldDiff{
+							{
+								Type: DiffTypeAdded,
+								Name: "GetterMode",
+								Old:  "",
+								New:  "file",
+							},
 							{
 								Type: DiffTypeAdded,
 								Name: "GetterOptions[bam]",
@@ -2522,6 +2530,12 @@ func TestTaskDiff(t *testing.T) {
 						Type: DiffTypeDeleted,
 						Name: "Artifact",
 						Fields: []*FieldDiff{
+							{
+								Type: DiffTypeDeleted,
+								Name: "GetterMode",
+								Old:  "dir",
+								New:  "",
+							},
 							{
 								Type: DiffTypeDeleted,
 								Name: "GetterOptions[bar]",

nomad/structs/structs.go

@@ -78,6 +78,10 @@ const (
 	ProtocolVersion = "protocol"
 	APIMajorVersion = "api.major"
 	APIMinorVersion = "api.minor"
+
+	GetterModeAny  = "any"
+	GetterModeFile = "file"
+	GetterModeDir  = "dir"
 )
 
 // RPCInfo is used to describe common information about query
@@ -3405,6 +3409,10 @@ type TaskArtifact struct {
 	// go-getter.
 	GetterOptions map[string]string
 
+	// GetterMode is the go-getter.ClientMode for fetching resources.
+	// Defaults to "any" but can be set to "file" or "dir".
+	GetterMode string
+
 	// RelativeDest is the download destination given relative to the task's
 	// directory.
 	RelativeDest string
@@ -3453,6 +3461,17 @@ func (ta *TaskArtifact) Validate() error {
 		mErr.Errors = append(mErr.Errors, fmt.Errorf("source must be specified"))
 	}
 
+	switch ta.GetterMode {
+	case "":
+		// Default to any
+		ta.GetterMode = GetterModeAny
+	case GetterModeAny, GetterModeFile, GetterModeDir:
+		// Ok
+	default:
+		mErr.Errors = append(mErr.Errors, fmt.Errorf("invalid artifact mode %q; must be one of: %s, %s, %s",
+			ta.GetterMode, GetterModeAny, GetterModeFile, GetterModeDir))
+	}
+
 	escaped, err := PathEscapesAllocDir("task", ta.RelativeDest)
 	if err != nil {
 		mErr.Errors = append(mErr.Errors, fmt.Errorf("invalid destination path: %v", err))

vendor/github.com/hashicorp/go-getter/appveyor.yml

@@ -1,5 +1,5 @@
 version: "build-{branch}-{build}"
-image: Visual Studio 2015
+image: Visual Studio 2017
 clone_folder: c:\gopath\github.com\hashicorp\go-getter
 environment:
   GOPATH: c:\gopath