*: implement ability to add tmpfs volumes to containers

* Add a generic container volume option that currently only support tmpfs. In
future it could be expanded to use of host volumes or other kind of volumes (if
supported by the underlying executor)

* Implement creation of tmpfs volumes in docker and k8s drivers.

internal/config/config.go

@@ -26,6 +26,7 @@ import (
 	"github.com/ghodss/yaml"
 	"github.com/google/go-jsonnet"
 	errors "golang.org/x/xerrors"
+	"k8s.io/apimachinery/pkg/api/resource"
 )
 
 const (
@@ -92,6 +93,17 @@ type Container struct {
 	User        string           `json:"user"`
 	Privileged  bool             `json:"privileged"`
 	Entrypoint  string           `json:"entrypoint"`
+	Volumes     []Volume         `json:"volumes"`
+}
+
+type Volume struct {
+	Path string `json:"path"`
+
+	TmpFS *VolumeTmpFS `json:"tmpfs"`
+}
+
+type VolumeTmpFS struct {
+	Size *resource.Quantity `json:"size"`
 }
 
 type Run struct {
@@ -711,6 +723,14 @@ func checkConfig(config *Config) error {
 					return errors.Errorf("task %q runtime: invalid arch %q", task.Name, r.Arch)
 				}
 			}
+
+			for _, container := range r.Containers {
+				for _, vol := range container.Volumes {
+					if vol.TmpFS == nil {
+						return errors.Errorf("no volume config specified")
+					}
+				}
+			}
 		}
 	}
 

internal/config/config_test.go

@@ -23,6 +23,7 @@ import (
 
 	"github.com/google/go-cmp/cmp"
 	errors "golang.org/x/xerrors"
+	"k8s.io/apimachinery/pkg/api/resource"
 )
 
 func TestParseConfig(t *testing.T) {
@@ -324,11 +325,18 @@ func TestParseOutput(t *testing.T) {
                           type: pod
                           containers:
                             - image: image01
+                              volumes:
+                                - path: /mnt/tmpfs
+                                  tmpfs:
+                                    size: 1Gi
                       - name: task04
                         runtime:
                           type: pod
                           containers:
                             - image: image01
+                              volumes:
+                                - path: /mnt/tmpfs
+                                  tmpfs: {}
           `,
 			out: &Config{
 				Runs: []*Run{
@@ -489,6 +497,7 @@ func TestParseOutput(t *testing.T) {
 									Containers: []*Container{
 										&Container{
 											Image:   "image01",
+											Volumes: []Volume{{Path: "/mnt/tmpfs", TmpFS: &VolumeTmpFS{Size: resource.NewQuantity(1024*1024*1024, resource.BinarySI)}}},
 										},
 									},
 								},
@@ -504,6 +513,7 @@ func TestParseOutput(t *testing.T) {
 									Containers: []*Container{
 										&Container{
 											Image:   "image01",
+											Volumes: []Volume{{Path: "/mnt/tmpfs", TmpFS: &VolumeTmpFS{}}},
 										},
 									},
 								},
@@ -524,7 +534,16 @@ func TestParseOutput(t *testing.T) {
 			if err != nil {
 				t.Fatalf("unexpected error: %v", err)
 			}
-			if diff := cmp.Diff(tt.out, out); diff != "" {
+			if diff := cmp.Diff(tt.out, out, cmp.Comparer(func(x, y *resource.Quantity) bool {
+				if x == nil && y == nil {
+					return true
+				}
+				if x != nil && y != nil {
+					return x.Cmp(*y) == 0
+				}
+
+				return false
+			})); diff != "" {
 				t.Error(diff)
 			}
 		})

internal/runconfig/runconfig.go

@@ -40,8 +40,24 @@ func genRuntime(c *config.Config, ce *config.Runtime, variables map[string]strin
 			User:        cc.User,
 			Privileged:  cc.Privileged,
 			Entrypoint:  cc.Entrypoint,
+			Volumes:     make([]rstypes.Volume, len(cc.Volumes)),
 		}
 
+		for i, ccVol := range cc.Volumes {
+			container.Volumes[i] = rstypes.Volume{
+				Path: ccVol.Path,
+			}
+
+			if ccVol.TmpFS != nil {
+				var size int64
+				if ccVol.TmpFS.Size != nil {
+					size = ccVol.TmpFS.Size.Value()
+				}
+				container.Volumes[i].TmpFS = &rstypes.VolumeTmpFS{
+					Size: size,
+				}
+			}
+		}
 		containers = append(containers, container)
 	}
 

internal/runconfig/runconfig_test.go

@@ -23,6 +23,7 @@ import (
 	"agola.io/agola/internal/util"
 	rstypes "agola.io/agola/services/runservice/types"
 	"agola.io/agola/services/types"
+	"k8s.io/apimachinery/pkg/api/resource"
 
 	"github.com/google/go-cmp/cmp"
 	errors "golang.org/x/xerrors"
@@ -721,6 +722,16 @@ func TestGenRunConfig(t *testing.T) {
 												"ENVFROMVARIABLE01": config.Value{Type: config.ValueTypeFromVariable, Value: "variable01"},
 											},
 											User: "",
+											Volumes: []config.Volume{
+												config.Volume{
+													Path:  "/mnt/vol01",
+													TmpFS: &config.VolumeTmpFS{},
+												},
+												config.Volume{
+													Path:  "/mnt/vol01",
+													TmpFS: &config.VolumeTmpFS{Size: resource.NewQuantity(1024*1024*1024, resource.BinarySI)},
+												},
+											},
 										},
 									},
 								},
@@ -798,6 +809,16 @@ func TestGenRunConfig(t *testing.T) {
 									"ENV01":             "ENV01",
 									"ENVFROMVARIABLE01": "VARVALUE01",
 								},
+								Volumes: []rstypes.Volume{
+									rstypes.Volume{
+										Path:  "/mnt/vol01",
+										TmpFS: &rstypes.VolumeTmpFS{},
+									},
+									rstypes.Volume{
+										Path:  "/mnt/vol01",
+										TmpFS: &rstypes.VolumeTmpFS{Size: 1024 * 1024 * 1024},
+									},
+								},
 							},
 						},
 					},
@@ -874,6 +895,7 @@ func TestGenRunConfig(t *testing.T) {
 							{
 								Image:       "image01",
 								Environment: map[string]string{},
+								Volumes:     []rstypes.Volume{},
 							},
 						},
 					},
@@ -972,6 +994,7 @@ func TestGenRunConfig(t *testing.T) {
 							{
 								Image:       "image01",
 								Environment: map[string]string{},
+								Volumes:     []rstypes.Volume{},
 							},
 						},
 					},
@@ -989,9 +1012,6 @@ func TestGenRunConfig(t *testing.T) {
 		t.Run(tt.name, func(t *testing.T) {
 			out := GenRunConfigTasks(uuid, tt.in, "run01", tt.variables, "", "", "")
 
-			//if err != nil {
-			//	t.Fatalf("unexpected error: %v", err)
-			//}
 			if diff := cmp.Diff(tt.out, out); diff != "" {
 				t.Error(diff)
 			}

internal/services/executor/driver/docker.go

@@ -36,6 +36,7 @@ import (
 	dockertypes "github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/api/types/filters"
+	"github.com/docker/docker/api/types/mount"
 	"github.com/docker/docker/client"
 	"github.com/docker/docker/pkg/archive"
 	"github.com/docker/docker/pkg/stdcopy"
@@ -285,6 +286,7 @@ func (d *DockerDriver) createContainer(ctx context.Context, index int, podConfig
 	}
 	if index == 0 {
 		// main container requires the initvolume containing the toolbox
+		// TODO(sgotti) migrate this to cliHostConfig.Mounts
 		cliHostConfig.Binds = []string{fmt.Sprintf("%s:%s", d.initVolumeHostDir, podConfig.InitVolumeDir)}
 		cliHostConfig.ReadonlyPaths = []string{fmt.Sprintf("%s:%s", d.initVolumeHostDir, podConfig.InitVolumeDir)}
 	} else {
@@ -292,6 +294,22 @@ func (d *DockerDriver) createContainer(ctx context.Context, index int, podConfig
 		cliHostConfig.NetworkMode = container.NetworkMode(fmt.Sprintf("container:%s", maincontainerID))
 	}
 
+	for _, vol := range containerConfig.Volumes {
+		if vol.TmpFS != nil {
+			cliHostConfig.Mounts = []mount.Mount{
+				mount.Mount{
+					Type:   mount.TypeTmpfs,
+					Target: vol.Path,
+					TmpfsOptions: &mount.TmpfsOptions{
+						SizeBytes: vol.TmpFS.Size,
+					},
+				},
+			}
+		} else {
+			return nil, errors.Errorf("missing volume config")
+		}
+	}
+
 	resp, err := d.client.ContainerCreate(ctx, cliContainerConfig, cliHostConfig, nil, "")
 	return &resp, err
 }

internal/services/executor/driver/docker_test.go

@@ -370,4 +370,84 @@ func TestDockerPod(t *testing.T) {
 			t.Fatalf("pod with id %q not found", pod.ID())
 		}
 	})
+
+	t.Run("test pod with a tmpfs volume with size limit", func(t *testing.T) {
+		pod, err := d.NewPod(ctx, &PodConfig{
+			ID:     uuid.NewV4().String(),
+			TaskID: uuid.NewV4().String(),
+			Containers: []*ContainerConfig{
+				&ContainerConfig{
+					Cmd:   []string{"cat"},
+					Image: "busybox",
+					Volumes: []Volume{
+						{
+							Path: "/mnt/tmpfs",
+							TmpFS: &VolumeTmpFS{
+								Size: 1024 * 1024,
+							},
+						},
+					},
+				},
+			},
+			InitVolumeDir: "/tmp/agola",
+		}, ioutil.Discard)
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+		defer func() { _ = pod.Remove(ctx) }()
+
+		ce, err := pod.Exec(ctx, &ExecConfig{
+			Cmd: []string{"sh", "-c", "if [ $(cat /proc/mounts | grep /mnt/tmpfs | grep size=1024k | wc -l ) -ne 1 ]; then exit 1; fi"},
+		})
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+
+		code, err := ce.Wait(ctx)
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+		if code != 0 {
+			t.Fatalf("unexpected exit code: %d", code)
+		}
+	})
+
+	t.Run("test pod with a tmpfs volume without size limit", func(t *testing.T) {
+		pod, err := d.NewPod(ctx, &PodConfig{
+			ID:     uuid.NewV4().String(),
+			TaskID: uuid.NewV4().String(),
+			Containers: []*ContainerConfig{
+				&ContainerConfig{
+					Cmd:   []string{"cat"},
+					Image: "busybox",
+					Volumes: []Volume{
+						{
+							Path:  "/mnt/tmpfs",
+							TmpFS: &VolumeTmpFS{},
+						},
+					},
+				},
+			},
+			InitVolumeDir: "/tmp/agola",
+		}, ioutil.Discard)
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+		defer func() { _ = pod.Remove(ctx) }()
+
+		ce, err := pod.Exec(ctx, &ExecConfig{
+			Cmd: []string{"sh", "-c", "if [ $(cat /proc/mounts | grep /mnt/tmpfs | wc -l ) -ne 1 ]; then exit 1; fi"},
+		})
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+
+		code, err := ce.Wait(ctx)
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+		if code != 0 {
+			t.Fatalf("unexpected exit code: %d", code)
+		}
+	})
 }

internal/services/executor/driver/driver.go

@@ -93,6 +93,17 @@ type ContainerConfig struct {
 	Image      string
 	User       string
 	Privileged bool
+	Volumes    []Volume
+}
+
+type Volume struct {
+	Path string
+
+	TmpFS *VolumeTmpFS
+}
+
+type VolumeTmpFS struct {
+	Size int64
 }
 
 type ExecConfig struct {

internal/services/executor/driver/k8s.go

@@ -35,6 +35,7 @@ import (
 	errors "golang.org/x/xerrors"
 	corev1 "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	apilabels "k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/watch"
@@ -416,6 +417,37 @@ func (d *K8sDriver) NewPod(ctx context.Context, podConfig *PodConfig, out io.Wri
 				},
 			}
 		}
+
+		for vIndex, cVol := range containerConfig.Volumes {
+			var vol corev1.Volume
+			var volMount corev1.VolumeMount
+			if cVol.TmpFS != nil {
+				name := fmt.Sprintf("volume-%d-%d", cIndex, vIndex)
+				var sizeLimit *resource.Quantity
+				if cVol.TmpFS.Size != 0 {
+					sizeLimit = resource.NewQuantity(cVol.TmpFS.Size, resource.BinarySI)
+				}
+				vol = corev1.Volume{
+					Name: name,
+					VolumeSource: corev1.VolumeSource{
+						EmptyDir: &corev1.EmptyDirVolumeSource{
+							Medium:    corev1.StorageMediumMemory,
+							SizeLimit: sizeLimit,
+						},
+					},
+				}
+				volMount = corev1.VolumeMount{
+					Name:      name,
+					MountPath: cVol.Path,
+				}
+			} else {
+				return nil, errors.Errorf("missing volume config")
+			}
+
+			pod.Spec.Volumes = append(pod.Spec.Volumes, vol)
+			c.VolumeMounts = append(c.VolumeMounts, volMount)
+		}
+
 		pod.Spec.Containers = append(pod.Spec.Containers, c)
 	}
 

internal/services/executor/driver/k8s_test.go

@@ -259,6 +259,49 @@ func TestK8sPod(t *testing.T) {
 		}
 	})
 
+	t.Run("test pod with a tmpfs volume", func(t *testing.T) {
+		pod, err := d.NewPod(ctx, &PodConfig{
+			ID:     uuid.NewV4().String(),
+			TaskID: uuid.NewV4().String(),
+			Containers: []*ContainerConfig{
+				&ContainerConfig{
+					Cmd:   []string{"cat"},
+					Image: "busybox",
+					Volumes: []Volume{
+						{
+							Path: "/mnt/tmpfs",
+							TmpFS: &VolumeTmpFS{
+								Size: 1024 * 1024,
+							},
+						},
+					},
+				},
+			},
+			InitVolumeDir: "/tmp/agola",
+		}, ioutil.Discard)
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+		defer func() { _ = pod.Remove(ctx) }()
+
+		var buf bytes.Buffer
+		ce, err := pod.Exec(ctx, &ExecConfig{
+			// k8s doesn't set size=1024k in the tmpf mount options but uses other modes to detect the size
+			Cmd:    []string{"sh", "-c", "if [ $(cat /proc/mounts | grep /mnt/tmpfs | wc -l ) -ne 1 ]; then exit 1; fi"},
+			Stdout: &buf,
+		})
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+
+		code, err := ce.Wait(ctx)
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+		if code != 0 {
+			t.Fatalf("unexpected exit code: %d", code)
+		}
+	})
 }
 
 func TestParseGitVersion(t *testing.T) {

internal/services/executor/executor.go

@@ -893,13 +893,27 @@ func (e *Executor) setupTask(ctx context.Context, rt *runningTask) error {
 			cmd = strings.Split(c.Entrypoint, " ")
 		}
 
-		podConfig.Containers[i] = &driver.ContainerConfig{
+		containerConfig := &driver.ContainerConfig{
 			Image:      c.Image,
 			Cmd:        cmd,
 			Env:        c.Environment,
 			User:       c.User,
 			Privileged: c.Privileged,
+			Volumes:    make([]driver.Volume, len(c.Volumes)),
 		}
+
+		for vIndex, cVol := range c.Volumes {
+			containerConfig.Volumes[vIndex] = driver.Volume{
+				Path: cVol.Path,
+			}
+			if cVol.TmpFS != nil {
+				containerConfig.Volumes[vIndex].TmpFS = &driver.VolumeTmpFS{
+					Size: cVol.TmpFS.Size,
+				}
+			}
+		}
+
+		podConfig.Containers[i] = containerConfig
 	}
 
 	_, _ = outf.WriteString("Starting pod.\n")

services/runservice/types/types.go

@@ -543,6 +543,17 @@ type Container struct {
 	User        string            `json:"user,omitempty"`
 	Privileged  bool              `json:"privileged"`
 	Entrypoint  string            `json:"entrypoint"`
+	Volumes     []Volume          `json:"volumes"`
+}
+
+type Volume struct {
+	Path string `json:"path"`
+
+	TmpFS *VolumeTmpFS `json:"tmpfs"`
+}
+
+type VolumeTmpFS struct {
+	Size int64 `json:"size"`
 }
 
 type WorkspaceOperation struct {