Add downward API for environment vars

kubernetes · Apr 27, 2015 · 7d30f09 · 7d30f09
1 parent e0e83fa
commit 7d30f09
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Showing 21 changed files with 674 additions and 17 deletions.
diff --git a/pkg/api/testing/fuzzer.go b/pkg/api/testing/fuzzer.go
@@ -188,6 +188,20 @@ func FuzzerFor(t *testing.T, version string, src rand.Source) *fuzz.Fuzzer {
 			c.FuzzNoCustom(ct)                                          // fuzz self without calling this function again
 			ct.TerminationMessagePath = "/" + ct.TerminationMessagePath // Must be non-empty
 		},
+		func(ev *api.EnvVar, c fuzz.Continue) {
+			ev.Name = c.RandString()
+			if c.RandBool() {
+				ev.Value = c.RandString()
+			} else {
+				ev.ValueFrom = &api.EnvVarSource{}
+				ev.ValueFrom.FieldPath = &api.ObjectFieldSelector{}
+
+				versions := []string{"v1beta1", "v1beta2", "v1beta3"}
+
+				ev.ValueFrom.FieldPath.APIVersion = versions[c.Rand.Intn(len(versions))]
+				ev.ValueFrom.FieldPath.FieldPath = c.RandString()
+			}
+		},
 		func(e *api.Event, c fuzz.Continue) {
 			c.FuzzNoCustom(e) // fuzz self without calling this function again
 			// Fix event count to 1, otherwise, if a v1beta1 or v1beta2 event has a count set arbitrarily, it's count is ignored

diff --git a/pkg/api/types.go b/pkg/api/types.go
@@ -508,6 +508,25 @@ type EnvVar struct {
 	Name string `json:"name"`
 	// Optional: defaults to "".
 	Value string `json:"value,omitempty"`
+	// Optional: specify a source the value of this var should come from.
+	ValueFrom *EnvVarSource `json:"valueFrom,omitempty"`
+}
+
+// EnvVarSource represents a source for the value of an EnvVar.
+// Only one of its members may be specified.
+type EnvVarSource struct {
+	// Selects a field of the pod; only name and namespace are supported.
+	FieldPath *ObjectFieldSelector `json:"fieldPath,omitempty"`
+}
+
+// ObjectFieldSelector selects an APIVersioned field of an object.
+type ObjectFieldSelector struct {
+	// The API version the FieldPath is written in terms of.
+	// If no value is specified, it will be defaulted from the APIVersion
+	// the enclosing object is created with.
+	APIVersion string `json:"apiVersion,omitempty"`
+	// The path of the field to select in the specified API version
+	FieldPath string `json:"fieldPath,omitempty"`
 }
 
 // HTTPGetAction describes an action based on HTTP Get requests.

diff --git a/pkg/api/v1beta1/conversion.go b/pkg/api/v1beta1/conversion.go
@@ -116,6 +116,11 @@ func init() {
 			out.Value = in.Value
 			out.Key = in.Name
 			out.Name = in.Name
+
+			if err := s.Convert(&in.ValueFrom, &out.ValueFrom, 0); err != nil {
+				return err
+			}
+
 			return nil
 		},
 		func(in *EnvVar, out *newer.EnvVar, s conversion.Scope) error {
@@ -125,9 +130,13 @@ func init() {
 			} else {
 				out.Name = in.Key
 			}
+
+			if err := s.Convert(&in.ValueFrom, &out.ValueFrom, 0); err != nil {
+				return err
+			}
+
 			return nil
 		},
-
 		// Path & MountType are deprecated.
 		func(in *newer.VolumeMount, out *VolumeMount, s conversion.Scope) error {
 			out.Name = in.Name

diff --git a/pkg/api/v1beta1/defaults.go b/pkg/api/v1beta1/defaults.go
@@ -166,6 +166,11 @@ func init() {
 				obj.ExternalID = obj.ID
 			}
 		},
+		func(obj *ObjectFieldSelector) {
+			if obj.APIVersion == "" {
+				obj.APIVersion = "v1beta1"
+			}
+		},
 	)
 }
 

diff --git a/pkg/api/v1beta1/defaults_test.go b/pkg/api/v1beta1/defaults_test.go
@@ -294,3 +294,29 @@ func TestSetDefaultMinionExternalID(t *testing.T) {
 		t.Errorf("Expected default External ID: %s, got: %s", name, m2.ExternalID)
 	}
 }
+
+func TestSetDefaultObjectFieldSelectorAPIVersion(t *testing.T) {
+	s := current.ContainerManifest{
+		Containers: []current.Container{
+			{
+				Env: []current.EnvVar{
+					{
+						ValueFrom: &current.EnvVarSource{
+							FieldPath: &current.ObjectFieldSelector{},
+						},
+					},
+				},
+			},
+		},
+	}
+	obj2 := roundTrip(t, runtime.Object(&current.ContainerManifestList{
+		Items: []current.ContainerManifest{s},
+	}))
+	sList2 := obj2.(*current.ContainerManifestList)
+	s2 := sList2.Items[0]
+
+	apiVersion := s2.Containers[0].Env[0].ValueFrom.FieldPath.APIVersion
+	if apiVersion != "v1beta1" {
+		t.Errorf("Expected default APIVersion v1beta1, got: %v", apiVersion)
+	}
+}
diff --git a/pkg/api/v1beta1/types.go b/pkg/api/v1beta1/types.go
@@ -397,6 +397,23 @@ type EnvVar struct {
 	Key  string `json:"key,omitempty" description:"name of the environment variable; must be a C_IDENTIFIER; deprecated - use name instead"`
 	// Optional: defaults to "".
 	Value string `json:"value,omitempty" description:"value of the environment variable; defaults to empty string"`
+	// Optional: specify a source the value of this var should come from.
+	ValueFrom *EnvVarSource `json:"valueFrom,omitempty" description:"source for the environment variable's value; cannot be used if value is not empty"`
+}
+
+// EnvVarSource represents a source for the value of an EnvVar.
+// Only one of its members may be specified.
+type EnvVarSource struct {
+	// Selects a field of the pod; only name and namespace are supported.
+	FieldPath *ObjectFieldSelector `json:"fieldPath,omitempty" description:"selects a field of the pod; only name and namespace are supported"`
+}
+
+// ObjectFieldSelector selects an APIVersioned field of an object.
+type ObjectFieldSelector struct {
+	// The API version the FieldPath is written in terms of.
+	APIVersion string `json:"apiVersion,omitempty" description="The API version that FieldPath is written in terms of"`
+	// The path of the field to select in the specified API version
+	FieldPath string `json:"fieldPath,omitempty" description="The path of the field to select in the specified API version"`
 }
 
 // HTTPGetAction describes an action based on HTTP Get requests.

diff --git a/pkg/api/v1beta2/defaults.go b/pkg/api/v1beta2/defaults.go
@@ -167,6 +167,11 @@ func init() {
 				obj.ExternalID = obj.ID
 			}
 		},
+		func(obj *ObjectFieldSelector) {
+			if obj.APIVersion == "" {
+				obj.APIVersion = "v1beta2"
+			}
+		},
 	)
 }
 

diff --git a/pkg/api/v1beta2/defaults_test.go b/pkg/api/v1beta2/defaults_test.go
@@ -293,3 +293,29 @@ func TestSetDefaultMinionExternalID(t *testing.T) {
 		t.Errorf("Expected default External ID: %s, got: %s", name, m2.ExternalID)
 	}
 }
+
+func TestSetDefaultObjectFieldSelectorAPIVersion(t *testing.T) {
+	s := current.ContainerManifest{
+		Containers: []current.Container{
+			{
+				Env: []current.EnvVar{
+					{
+						ValueFrom: &current.EnvVarSource{
+							FieldPath: &current.ObjectFieldSelector{},
+						},
+					},
+				},
+			},
+		},
+	}
+	obj2 := roundTrip(t, runtime.Object(&current.ContainerManifestList{
+		Items: []current.ContainerManifest{s},
+	}))
+	sList2 := obj2.(*current.ContainerManifestList)
+	s2 := sList2.Items[0]
+
+	apiVersion := s2.Containers[0].Env[0].ValueFrom.FieldPath.APIVersion
+	if apiVersion != "v1beta2" {
+		t.Errorf("Expected default APIVersion v1beta2, got: %v", apiVersion)
+	}
+}
diff --git a/pkg/api/v1beta2/types.go b/pkg/api/v1beta2/types.go
@@ -381,6 +381,23 @@ type EnvVar struct {
 	Name string `json:"name" description:"name of the environment variable; must be a C_IDENTIFIER"`
 	// Optional: defaults to "".
 	Value string `json:"value,omitempty" description:"value of the environment variable; defaults to empty string"`
+	// Optional: specify a source the value of this var should come from.
+	ValueFrom *EnvVarSource `json:"valueFrom,omitempty" description:"source for the environment variable's value; cannot be used if value is not empty"`
+}
+
+// EnvVarSource represents a source for the value of an EnvVar.
+// Only one of its members may be specified.
+type EnvVarSource struct {
+	// Selects a field of the pod; only name and namespace are supported.
+	FieldPath *ObjectFieldSelector `json:"fieldPath,omitempty" description:"selects a field of the pod; only name and namespace are supported"`
+}
+
+// ObjectFieldSelector selects an APIVersioned field of an object.
+type ObjectFieldSelector struct {
+	// The API version the FieldPath is written in terms of.
+	APIVersion string `json:"apiVersion,omitempty" description="The API version that FieldPath is written in terms of"`
+	// The path of the field to select in the specified API version
+	FieldPath string `json:"fieldPath,omitempty" description="The path of the field to select in the specified API version"`
 }
 
 // HTTPGetAction describes an action based on HTTP Get requests.

diff --git a/pkg/api/v1beta3/conversion.go b/pkg/api/v1beta3/conversion.go
@@ -1794,6 +1794,23 @@ func init() {
 			out.Path = in.Path
 			return nil
 		},
+		func(in *EnvVar, out *newer.EnvVar, s conversion.Scope) error {
+			out.Name = in.Name
+			out.Value = in.Value
+			if err := s.Convert(&in.ValueFrom, &out.ValueFrom, 0); err != nil {
+				return err
+			}
+
+			return nil
+		},
+		func(in *newer.EnvVar, out *EnvVar, s conversion.Scope) error {
+			out.Name = in.Name
+			out.Value = in.Value
+			if err := s.Convert(&in.ValueFrom, &out.ValueFrom, 0); err != nil {
+				return err
+			}
+			return nil
+		},
 		func(in *PodSpec, out *newer.PodSpec, s conversion.Scope) error {
 			if in.Volumes != nil {
 				out.Volumes = make([]newer.Volume, len(in.Volumes))
@@ -2715,6 +2732,7 @@ func init() {
 		func(label, value string) (string, string, error) {
 			switch label {
 			case "metadata.name",
+				"metadata.namespace",
 				"status.phase",
 				"spec.host":
 				return label, value, nil

diff --git a/pkg/api/v1beta3/defaults.go b/pkg/api/v1beta3/defaults.go
@@ -128,6 +128,11 @@ func init() {
 				obj.Spec.ExternalID = obj.Name
 			}
 		},
+		func(obj *ObjectFieldSelector) {
+			if obj.APIVersion == "" {
+				obj.APIVersion = "v1beta3"
+			}
+		},
 	)
 }
 

diff --git a/pkg/api/v1beta3/defaults_test.go b/pkg/api/v1beta3/defaults_test.go
@@ -302,3 +302,30 @@ func TestSetDefaultNodeExternalID(t *testing.T) {
 		t.Errorf("Expected default External ID: %s, got: %s", name, n2.Spec.ExternalID)
 	}
 }
+
+func TestSetDefaultObjectFieldSelectorAPIVersion(t *testing.T) {
+	s := current.PodSpec{
+		Containers: []current.Container{
+			{
+				Env: []current.EnvVar{
+					{
+						ValueFrom: &current.EnvVarSource{
+							FieldPath: &current.ObjectFieldSelector{},
+						},
+					},
+				},
+			},
+		},
+	}
+	pod := &current.Pod{
+		Spec: s,
+	}
+	obj2 := roundTrip(t, runtime.Object(pod))
+	pod2 := obj2.(*current.Pod)
+	s2 := pod2.Spec
+
+	apiVersion := s2.Containers[0].Env[0].ValueFrom.FieldPath.APIVersion
+	if apiVersion != "v1beta3" {
+		t.Errorf("Expected default APIVersion v1beta3, got: %v", apiVersion)
+	}
+}
diff --git a/pkg/api/v1beta3/types.go b/pkg/api/v1beta3/types.go
@@ -519,6 +519,23 @@ type EnvVar struct {
 	Name string `json:"name" description:"name of the environment variable; must be a C_IDENTIFIER"`
 	// Optional: defaults to "".
 	Value string `json:"value,omitempty" description:"value of the environment variable; defaults to empty string"`
+	// Optional: specify a source the value of this var should come from.
+	ValueFrom *EnvVarSource `json:"valueFrom,omitempty" description:"source for the environment variable's value; cannot be used if value is not empty"`
+}
+
+// EnvVarSource represents a source for the value of an EnvVar.
+// Only one of its members may be specified.
+type EnvVarSource struct {
+	// Selects a field of the pod; only name and namespace are supported.
+	FieldPath *ObjectFieldSelector `json:"fieldPath,omitempty" description:"selects a field of the pod; only name and namespace are supported"`
+}
+
+// ObjectFieldSelector selects an APIVersioned field of an object.
+type ObjectFieldSelector struct {
+	// The API version the FieldPath is written in terms of.
+	APIVersion string `json:"apiVersion,omitempty" description="The API version that FieldPath is written in terms of"`
+	// The path of the field to select in the specified API version
+	FieldPath string `json:"fieldPath,omitempty" description="The path of the field to select in the specified API version"`
 }
 
 // HTTPGetAction describes an action based on HTTP Get requests.

diff --git a/pkg/api/validation/validation.go b/pkg/api/validation/validation.go
@@ -555,15 +555,58 @@ func validateEnv(vars []api.EnvVar) errs.ValidationErrorList {
 		vErrs := errs.ValidationErrorList{}
 		if len(ev.Name) == 0 {
 			vErrs = append(vErrs, errs.NewFieldRequired("name"))
-		}
-		if !util.IsCIdentifier(ev.Name) {
+		} else if !util.IsCIdentifier(ev.Name) {
 			vErrs = append(vErrs, errs.NewFieldInvalid("name", ev.Name, cIdentifierErrorMsg))
 		}
+		vErrs = append(vErrs, validateEnvVarValueFrom(ev).Prefix("valueFrom")...)
 		allErrs = append(allErrs, vErrs.PrefixIndex(i)...)
 	}
 	return allErrs
 }
 
+func validateEnvVarValueFrom(ev api.EnvVar) errs.ValidationErrorList {
+	allErrs := errs.ValidationErrorList{}
+
+	if ev.ValueFrom == nil {
+		return allErrs
+	}
+
+	numSources := 0
+
+	switch {
+	case ev.ValueFrom.FieldPath != nil:
+		numSources++
+		allErrs = append(allErrs, validateObjectFieldSelector(ev.ValueFrom.FieldPath).Prefix("fieldPath")...)
+	}
+
+	if ev.Value != "" && numSources != 0 {
+		allErrs = append(allErrs, errs.NewFieldInvalid("", "", "sources cannot be specified when value is not empty"))
+	}
+
+	return allErrs
+}
+
+var validFieldPathExpressions = util.NewStringSet("metadata.name", "metadata.namespace")
+
+func validateObjectFieldSelector(fs *api.ObjectFieldSelector) errs.ValidationErrorList {
+	allErrs := errs.ValidationErrorList{}
+
+	if fs.APIVersion == "" {
+		allErrs = append(allErrs, errs.NewFieldRequired("apiVersion"))
+	} else if fs.FieldPath == "" {
+		allErrs = append(allErrs, errs.NewFieldRequired("fieldPath"))
+	} else {
+		internalFieldPath, _, err := api.Scheme.ConvertFieldLabel(fs.APIVersion, "Pod", fs.FieldPath, "")
+		if err != nil {
+			allErrs = append(allErrs, errs.NewFieldInvalid("fieldPath", fs.FieldPath, "error converting fieldPath"))
+		} else if !validFieldPathExpressions.Has(internalFieldPath) {
+			allErrs = append(allErrs, errs.NewFieldNotSupported("fieldPath", internalFieldPath))
+		}
+	}
+
+	return allErrs
+}
+
 func validateVolumeMounts(mounts []api.VolumeMount, volumes util.StringSet) errs.ValidationErrorList {
 	allErrs := errs.ValidationErrorList{}