interfaces: add new interface API

interfaces/apparmor/backend.go

@@ -55,8 +55,8 @@ import (
 type Backend struct{}
 
 // Name returns the name of the backend.
-func (b *Backend) Name() string {
-	return "apparmor"
+func (b *Backend) Name() interfaces.SecuritySystem {
+	return interfaces.SecurityAppArmor
 }
 
 // Setup creates and loads apparmor profiles specific to a given snap.
@@ -205,3 +205,7 @@ func unloadProfiles(profiles []string) error {
 	}
 	return nil
 }
+
+func (b *Backend) NewSpecification() interfaces.Specification {
+	panic(fmt.Errorf("%s is not using specifications yet", b.Name()))
+}

interfaces/apparmor/backend_test.go

@@ -105,7 +105,7 @@ func (s *backendSuite) TearDownTest(c *C) {
 // Tests for Setup() and Remove()
 
 func (s *backendSuite) TestName(c *C) {
-	c.Check(s.Backend.Name(), Equals, "apparmor")
+	c.Check(s.Backend.Name(), Equals, interfaces.SecurityAppArmor)
 }
 
 func (s *backendSuite) TestInstallingSnapWritesAndLoadsProfiles(c *C) {

interfaces/backend.go

@@ -69,7 +69,7 @@ type ConfinementOptions struct {
 type SecurityBackend interface {
 	// Name returns the name of the backend.
 	// This is intended for diagnostic messages.
-	Name() string
+	Name() SecuritySystem
 
 	// Setup creates and loads security artefacts specific to a given snap.
 	// The snap can be in one of three kids onf confinement (strict mode,
@@ -84,4 +84,7 @@ type SecurityBackend interface {
 	//
 	// This method should be called during the process of removing a snap.
 	Remove(snapName string) error
+
+	// NewSpecification returns a new specification associated with this backend.
+	NewSpecification() Specification
 }

interfaces/core.go

@@ -157,6 +157,18 @@ type Interface interface {
 	AutoConnect(plug *Plug, slot *Slot) bool
 }
 
+// Specification describes interactions between backends and interfaces.
+type Specification interface {
+	// AddPermanentSlot records side-effects of having a slot.
+	AddPermanentSlot(iface Interface, slot *Slot) error
+	// AddPermanentPlug records side-effects of having a plug.
+	AddPermanentPlug(iface Interface, plug *Plug) error
+	// AddConnectedSlot records side-effects of having a connected slot.
+	AddConnectedSlot(iface Interface, plug *Plug, slot *Slot) error
+	// AddConnectedPlug records side-effects of having a connected plug.
+	AddConnectedPlug(iface Interface, plug *Plug, slot *Slot) error
+}
+
 // SecuritySystem is a name of a security system.
 type SecuritySystem string
 

interfaces/dbus/backend.go

@@ -42,7 +42,7 @@ import (
 type Backend struct{}
 
 // Name returns the name of the backend.
-func (b *Backend) Name() string {
+func (b *Backend) Name() interfaces.SecuritySystem {
 	return "dbus"
 }
 
@@ -131,3 +131,7 @@ func addContent(securityTag string, executableSnippets [][]byte, content map[str
 		Mode:    0644,
 	}
 }
+
+func (b *Backend) NewSpecification() interfaces.Specification {
+	panic(fmt.Errorf("%s is not using specifications yet", b.Name()))
+}

interfaces/dbus/backend_test.go

@@ -61,7 +61,7 @@ func (s *backendSuite) TearDownTest(c *C) {
 
 // Tests for Setup() and Remove()
 func (s *backendSuite) TestName(c *C) {
-	c.Check(s.Backend.Name(), Equals, "dbus")
+	c.Check(s.Backend.Name(), Equals, interfaces.SecurityDBus)
 }
 
 func (s *backendSuite) TestInstallingSnapWritesConfigFiles(c *C) {

interfaces/ifacetest/testbackend.go → interfaces/ifacetest/backend.go

@@ -45,7 +45,7 @@ type TestSetupCall struct {
 }
 
 // Name returns the name of the security backend.
-func (b *TestSecurityBackend) Name() string {
+func (b *TestSecurityBackend) Name() interfaces.SecuritySystem {
 	return "test"
 }
 
@@ -66,3 +66,7 @@ func (b *TestSecurityBackend) Remove(snapName string) error {
 	}
 	return b.RemoveCallback(snapName)
 }
+
+func (b *TestSecurityBackend) NewSpecification() interfaces.Specification {
+	return &Specification{}
+}

interfaces/ifacetest/spec.go

@@ -0,0 +1,80 @@
+// -*- Mode: Go; indent-tabs-mode: t -*-
+
+/*
+ * Copyright (C) 2017 Canonical Ltd
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package ifacetest
+
+import (
+	"github.com/snapcore/snapd/interfaces"
+)
+
+// Specification is a specification intended for testing.
+type Specification struct {
+	Snippets []string
+}
+
+// AddSnippet appends a snippet to a list stored in the specification.
+func (spec *Specification) AddSnippet(snippet string) {
+	spec.Snippets = append(spec.Snippets, snippet)
+}
+
+// Implementation of methods required by interfaces.Specification
+
+// AddConnectedPlug records test side-effects of having a connected plug.
+func (spec *Specification) AddConnectedPlug(iface interfaces.Interface, plug *interfaces.Plug, slot *interfaces.Slot) error {
+	type definer interface {
+		TestConnectedPlug(spec *Specification, plug *interfaces.Plug, slot *interfaces.Slot) error
+	}
+	if iface, ok := iface.(definer); ok {
+		return iface.TestConnectedPlug(spec, plug, slot)
+	}
+	return nil
+}
+
+// AddConnectedSlot records test side-effects of having a connected slot.
+func (spec *Specification) AddConnectedSlot(iface interfaces.Interface, plug *interfaces.Plug, slot *interfaces.Slot) error {
+	type definer interface {
+		TestConnectedSlot(spec *Specification, plug *interfaces.Plug, slot *interfaces.Slot) error
+	}
+	if iface, ok := iface.(definer); ok {
+		return iface.TestConnectedSlot(spec, plug, slot)
+	}
+	return nil
+}
+
+// AddPermanentPlug records test side-effects of having a plug.
+func (spec *Specification) AddPermanentPlug(iface interfaces.Interface, plug *interfaces.Plug) error {
+	type definer interface {
+		TestPermanentPlug(spec *Specification, plug *interfaces.Plug) error
+	}
+	if iface, ok := iface.(definer); ok {
+		return iface.TestPermanentPlug(spec, plug)
+	}
+	return nil
+}
+
+// AddPermanentSlot records test side-effects of having a slot.
+func (spec *Specification) AddPermanentSlot(iface interfaces.Interface, slot *interfaces.Slot) error {
+	type definer interface {
+		TestPermanentSlot(spec *Specification, slot *interfaces.Slot) error
+	}
+	if iface, ok := iface.(definer); ok {
+		return iface.TestPermanentSlot(spec, slot)
+	}
+	return nil
+}

interfaces/ifacetest/spec_test.go

@@ -0,0 +1,93 @@
+// -*- Mode: Go; indent-tabs-mode: t -*-
+
+/*
+ * Copyright (C) 2015-2017 Canonical Ltd
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package ifacetest_test
+
+import (
+	. "gopkg.in/check.v1"
+
+	"github.com/snapcore/snapd/interfaces"
+	"github.com/snapcore/snapd/interfaces/ifacetest"
+	"github.com/snapcore/snapd/snap"
+)
+
+type SpecificationSuite struct {
+	iface *ifacetest.TestInterface
+	spec  *ifacetest.Specification
+	plug  *interfaces.Plug
+	slot  *interfaces.Slot
+}
+
+var _ = Suite(&SpecificationSuite{
+	iface: &ifacetest.TestInterface{
+		InterfaceName: "test",
+		TestConnectedPlugCallback: func(spec *ifacetest.Specification, plug *interfaces.Plug, slot *interfaces.Slot) error {
+			spec.AddSnippet("connected-plug")
+			return nil
+		},
+		TestConnectedSlotCallback: func(spec *ifacetest.Specification, plug *interfaces.Plug, slot *interfaces.Slot) error {
+			spec.AddSnippet("connected-slot")
+			return nil
+		},
+		TestPermanentPlugCallback: func(spec *ifacetest.Specification, plug *interfaces.Plug) error {
+			spec.AddSnippet("permanent-plug")
+			return nil
+		},
+		TestPermanentSlotCallback: func(spec *ifacetest.Specification, slot *interfaces.Slot) error {
+			spec.AddSnippet("permanent-slot")
+			return nil
+		},
+	},
+	plug: &interfaces.Plug{
+		PlugInfo: &snap.PlugInfo{
+			Snap:      &snap.Info{SuggestedName: "snap"},
+			Name:      "name",
+			Interface: "test",
+		},
+	},
+	slot: &interfaces.Slot{
+		SlotInfo: &snap.SlotInfo{
+			Snap:      &snap.Info{SuggestedName: "snap"},
+			Name:      "name",
+			Interface: "test",
+		},
+	},
+})
+
+func (s *SpecificationSuite) SetUpTest(c *C) {
+	s.spec = &ifacetest.Specification{}
+}
+
+// AddSnippet is not broken
+func (s *SpecificationSuite) TestAddSnippet(c *C) {
+	s.spec.AddSnippet("hello")
+	s.spec.AddSnippet("world")
+	c.Assert(s.spec.Snippets, DeepEquals, []string{"hello", "world"})
+}
+
+// The Specification can be used through the interfaces.Specification interface
+func (s *SpecificationSuite) SpecificationIface(c *C) {
+	var r interfaces.Specification = s.spec
+	c.Assert(r.AddConnectedPlug(s.iface, s.plug, s.slot), IsNil)
+	c.Assert(r.AddConnectedSlot(s.iface, s.plug, s.slot), IsNil)
+	c.Assert(r.AddPermanentPlug(s.iface, s.plug), IsNil)
+	c.Assert(r.AddPermanentSlot(s.iface, s.slot), IsNil)
+	c.Assert(s.spec.Snippets, DeepEquals, []string{
+		"connected-plug", "connected-slot", "permanent-plug", "permanent-slot"})
+}

interfaces/ifacetest/testtype.go → interfaces/ifacetest/testiface.go

@@ -1,7 +1,7 @@
 // -*- Mode: Go; indent-tabs-mode: t -*-
 
 /*
- * Copyright (C) 2015 Canonical Ltd
+ * Copyright (C) 2015-2017 Canonical Ltd
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
@@ -44,6 +44,13 @@ type TestInterface struct {
 	PlugSnippetCallback func(plug *interfaces.Plug, slot *interfaces.Slot, securitySystem interfaces.SecuritySystem) ([]byte, error)
 	// PermanentPlugSnippetCallback is the callback invoked inside PermanentPlugSnippet()
 	PermanentPlugSnippetCallback func(plug *interfaces.Plug, securitySystem interfaces.SecuritySystem) ([]byte, error)
+
+	// Support for interacting with the test backend.
+
+	TestConnectedPlugCallback func(spec *Specification, plug *interfaces.Plug, slot *interfaces.Slot) error
+	TestConnectedSlotCallback func(spec *Specification, plug *interfaces.Plug, slot *interfaces.Slot) error
+	TestPermanentPlugCallback func(spec *Specification, plug *interfaces.Plug) error
+	TestPermanentSlotCallback func(spec *Specification, slot *interfaces.Slot) error
 }
 
 // String() returns the same value as Name().
@@ -123,3 +130,33 @@ func (t *TestInterface) AutoConnect(plug *interfaces.Plug, slot *interfaces.Slot
 	}
 	return true
 }
+
+// Support for interacting with the test backend.
+
+func (t *TestInterface) TestConnectedPlug(spec *Specification, plug *interfaces.Plug, slot *interfaces.Slot) error {
+	if t.TestConnectedPlugCallback != nil {
+		return t.TestConnectedPlugCallback(spec, plug, slot)
+	}
+	return nil
+}
+
+func (t *TestInterface) TestConnectedSlot(spec *Specification, plug *interfaces.Plug, slot *interfaces.Slot) error {
+	if t.TestConnectedSlotCallback != nil {
+		return t.TestConnectedSlotCallback(spec, plug, slot)
+	}
+	return nil
+}
+
+func (t *TestInterface) TestPermanentPlug(spec *Specification, plug *interfaces.Plug) error {
+	if t.TestPermanentPlugCallback != nil {
+		return t.TestPermanentPlugCallback(spec, plug)
+	}
+	return nil
+}
+
+func (t *TestInterface) TestPermanentSlot(spec *Specification, slot *interfaces.Slot) error {
+	if t.TestPermanentSlotCallback != nil {
+		return t.TestPermanentSlotCallback(spec, slot)
+	}
+	return nil
+}

interfaces/ifacetest/testtype_test.go → interfaces/ifacetest/testiface_test.go

@@ -1,7 +1,7 @@
 // -*- Mode: Go; indent-tabs-mode: t -*-
 
 /*
- * Copyright (C) 2015 Canonical Ltd
+ * Copyright (C) 2015-2017 Canonical Ltd
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as

interfaces/kmod/backend.go

@@ -52,7 +52,7 @@ import (
 type Backend struct{}
 
 // Name returns the name of the backend.
-func (b *Backend) Name() string {
+func (b *Backend) Name() interfaces.SecuritySystem {
 	return "kmod"
 }
 
@@ -150,3 +150,7 @@ func uniqueLines(lines []string) (deduplicated []string) {
 	}
 	return deduplicated
 }
+
+func (b *Backend) NewSpecification() interfaces.Specification {
+	panic(fmt.Errorf("%s is not using specifications yet", b.Name()))
+}

interfaces/kmod/backend_test.go

@@ -64,7 +64,7 @@ func (s *backendSuite) TearDownTest(c *C) {
 }
 
 func (s *backendSuite) TestName(c *C) {
-	c.Check(s.Backend.Name(), Equals, "kmod")
+	c.Check(s.Backend.Name(), Equals, interfaces.SecurityKMod)
 }
 
 func (s *backendSuite) TestUniqueLines(c *C) {

interfaces/mount/backend.go

@@ -44,8 +44,8 @@ import (
 type Backend struct{}
 
 // Name returns the name of the backend.
-func (b *Backend) Name() string {
-	return "mount"
+func (b *Backend) Name() interfaces.SecuritySystem {
+	return interfaces.SecurityMount
 }
 
 // Setup creates mount mount profile files specific to a given snap.
@@ -128,3 +128,7 @@ func addContent(securityTag string, executableSnippets [][]byte, content map[str
 		Mode:    0644,
 	}
 }
+
+func (b *Backend) NewSpecification() interfaces.Specification {
+	panic(fmt.Errorf("%s is not using specifications yet", b.Name()))
+}