Enabling multi-tenancy for fission objects. (#655)

This feature allows creation of fission objects in different namespaces, in addition to retaining the existing behavior of creating fission objects in default namespace if user doesnt provide one. 
It also removes cluster admin roles for fission-fetcher and fission-builder Service Accounts and grants them only those privileges that they need.

fission/environment.go

@@ -28,9 +28,24 @@ import (
 	"k8s.io/client-go/pkg/api/v1"
 
 	"github.com/fission/fission"
+	"github.com/fission/fission/controller/client"
 	"github.com/fission/fission/crd"
 )
 
+func getFunctionsByEnvironment(client *client.Client, envName, envNamespace string) ([]crd.Function, error) {
+	fnList, err := client.FunctionList(metav1.NamespaceAll)
+	if err != nil {
+		return nil, err
+	}
+	fns := []crd.Function{}
+	for _, fn := range fnList {
+		if fn.Spec.Environment.Name == envName && fn.Spec.Environment.Namespace == envNamespace {
+			fns = append(fns, fn)
+		}
+	}
+	return fns, nil
+}
+
 func envCreate(c *cli.Context) error {
 	client := getClient(c.GlobalString("server"))
 
@@ -38,6 +53,14 @@ func envCreate(c *cli.Context) error {
 	if len(envName) == 0 {
 		fatal("Need a name, use --name.")
 	}
+	envNamespace := c.String("envNamespace")
+
+	envList, err := client.EnvironmentList(envNamespace)
+	if err == nil && len(envList) > 0 {
+		warn(fmt.Sprintf("%d environment(s) are present in this ns: %s. All these envs share"+
+			" the same service account token, with previleges to view secrets of all the functions referencing them. "+
+			"Envs can be created in different ns if isolation is needed", len(envList), envNamespace))
+	}
 
 	var poolsize int
 	if c.IsSet("poolsize") {
@@ -80,7 +103,7 @@ func envCreate(c *cli.Context) error {
 	env := &crd.Environment{
 		Metadata: metav1.ObjectMeta{
 			Name:      envName,
-			Namespace: metav1.NamespaceDefault,
+			Namespace: envNamespace,
 		},
 		Spec: fission.EnvironmentSpec{
 			Version: envVersion,
@@ -106,7 +129,7 @@ func envCreate(c *cli.Context) error {
 		return nil
 	}
 
-	_, err := client.EnvironmentCreate(env)
+	_, err = client.EnvironmentCreate(env)
 	checkErr(err, "create environment")
 
 	fmt.Printf("environment '%v' created\n", envName)
@@ -120,10 +143,11 @@ func envGet(c *cli.Context) error {
 	if len(envName) == 0 {
 		fatal("Need a name, use --name.")
 	}
+	envNamespace := c.String("envNamespace")
 
 	m := &metav1.ObjectMeta{
 		Name:      envName,
-		Namespace: metav1.NamespaceDefault,
+		Namespace: envNamespace,
 	}
 	env, err := client.EnvironmentGet(m)
 	checkErr(err, "get environment")
@@ -143,6 +167,7 @@ func envUpdate(c *cli.Context) error {
 	if len(envName) == 0 {
 		fatal("Need a name, use --name.")
 	}
+	envNamespace := c.String("envNamespace")
 
 	envImg := c.String("image")
 	envBuilderImg := c.String("builder")
@@ -155,7 +180,7 @@ func envUpdate(c *cli.Context) error {
 
 	env, err := client.EnvironmentGet(&metav1.ObjectMeta{
 		Name:      envName,
-		Namespace: metav1.NamespaceDefault,
+		Namespace: envNamespace,
 	})
 	checkErr(err, "find environment")
 
@@ -198,10 +223,11 @@ func envDelete(c *cli.Context) error {
 	if len(envName) == 0 {
 		fatal("Need a name , use --name.")
 	}
+	envNamespace := c.String("envNamespace")
 
 	m := &metav1.ObjectMeta{
 		Name:      envName,
-		Namespace: metav1.NamespaceDefault,
+		Namespace: envNamespace,
 	}
 	err := client.EnvironmentDelete(m)
 	checkErr(err, "delete environment")
@@ -212,8 +238,9 @@ func envDelete(c *cli.Context) error {
 
 func envList(c *cli.Context) error {
 	client := getClient(c.GlobalString("server"))
+	envNamespace := c.String("envNamespace")
 
-	envs, err := client.EnvironmentList()
+	envs, err := client.EnvironmentList(envNamespace)
 	checkErr(err, "list environments")
 
 	w := tabwriter.NewWriter(os.Stdout, 0, 0, 1, ' ', 0)