Prevent duplicated snap name and snap files when parsing seed.yaml.

2 files changed, 46 insertions, 0 deletions

diff --git a/snap/seed_yaml.go b/snap/seed_yaml.go
index 60f1724573..1a591cec47 100644
--- a/snap/seed_yaml.go
+++ b/snap/seed_yaml.go
@@ -70,6 +70,8 @@ func ReadSeedYaml(fn string) (*Seed, error) {
	return nil, fmt.Errorf("%s: cannot unmarshal %q: %s", errPrefix, yamlData, err)
	}
 
+	seenNames := make(map[string]bool, len(seed.Snaps))
+	seenFiles := make(map[string]bool, len(seed.Snaps))
	// validate
	for _, sn := range seed.Snaps {
	if sn == nil {
@@ -89,6 +91,16 @@ func ReadSeedYaml(fn string) (*Seed, error) {
	if strings.Contains(sn.File, "/") {
	return nil, fmt.Errorf("%s: %q must be a filename, not a path", errPrefix, sn.File)
	}
+
+	// make sure names and file names are unique
+	if seenNames[sn.Name] {
+	return nil, fmt.Errorf("%s: snap name %q not unique", errPrefix, sn.Name)
+	}
+	seenNames[sn.Name] = true
+	if seenFiles[sn.File] {
+	return nil, fmt.Errorf("%s: snap file %q for snap %q not unique", errPrefix, sn.File, sn.Name)
+	}
+	seenFiles[sn.File] = true
	}
 
	return &seed, nil
diff --git a/snap/seed_yaml_test.go b/snap/seed_yaml_test.go
index b067663357..670bafe5ca 100644
--- a/snap/seed_yaml_test.go
+++ b/snap/seed_yaml_test.go
@@ -82,6 +82,40 @@ func (s *seedYamlTestSuite) TestNoPathAllowed(c *C) {
	c.Assert(err, ErrorMatches, `cannot read seed yaml: "foo/bar.snap" must be a filename, not a path`)
 }
 
+func (s *seedYamlTestSuite) TestDuplicatedSnapName(c *C) {
+	fn := filepath.Join(c.MkDir(), "seed.yaml")
+	err := ioutil.WriteFile(fn, []byte(`
+snaps:
+ - name: foo
+ channel: stable
+ file: foo_1.0_all.snap
+ - name: foo
+ channel: edge
+ file: bar_1.0_all.snap
+`), 0644)
+	c.Assert(err, IsNil)
+
+	_, err = snap.ReadSeedYaml(fn)
+	c.Assert(err, ErrorMatches, `cannot read seed yaml: snap name "foo" not unique`)
+}
+
+func (s *seedYamlTestSuite) TestDuplicatedSnapFile(c *C) {
+	fn := filepath.Join(c.MkDir(), "seed.yaml")
+	err := ioutil.WriteFile(fn, []byte(`
+snaps:
+ - name: foo
+ channel: stable
+ file: foo_1.0_all.snap
+ - name: bar
+ channel: edge
+ file: foo_1.0_all.snap
+`), 0644)
+	c.Assert(err, IsNil)
+
+	_, err = snap.ReadSeedYaml(fn)
+	c.Assert(err, ErrorMatches, `cannot read seed yaml: snap file "foo_1.0_all.snap" for snap "bar" not unique`)
+}
+
 func (s *seedYamlTestSuite) TestValidateChannelUnhappy(c *C) {
	fn := filepath.Join(c.MkDir(), "seed.yaml")
	err := ioutil.WriteFile(fn, []byte(`