Enforce presence of Key and Value keys on field tag definition (googl…

…e#266)

.github/workflows/ci.yaml

@@ -53,7 +53,8 @@ jobs:
           staticcheck ./...
 
       - name: Check YAML
-        uses: ibiqlik/action-yamllint@v3
+        run: |
+          yamllint .
 
   test:
     name: Test

configuration/README.md

@@ -38,7 +38,7 @@ The tag `levee:"source"` is built-in. Additional tags may be identified via expl
 ```yaml
 FieldTags:
 - Key: levee
-  Val: source
+  Value: source
 ```
 
 Sinks and sanitizers are identified by package, method, and (if applicable) receiver name.

internal/pkg/config/config.go

@@ -66,7 +66,7 @@ func (c Config) IsSourceFieldTag(tag string) bool {
 	for _, ft := range c.FieldTags {
 		val := st.Get(ft.Key)
 		for _, v := range strings.Split(val, ",") {
-			if v == ft.Val {
+			if v == ft.Value {
 				return true
 			}
 		}
@@ -141,18 +141,18 @@ func (vacuousMatcher) MatchString(string) bool {
 }
 
 type fieldTagMatcher struct {
-	Key string
-	Val string
+	Key   string
+	Value string
 }
 
 // this type uses the default unmarshaller and mirrors configuration key-value pairs
 type rawFieldTagMatcher struct {
-	Key string
-	Val string
+	Key   string
+	Value string
 }
 
 func (ft *fieldTagMatcher) UnmarshalJSON(bytes []byte) error {
-	validFieldTagMatcherFields := []string{"key", "val", "value"}
+	validFieldTagMatcherFields := []string{"key", "value"}
 	if err := validateFieldNames(&bytes, "fieldTagMatcher", validFieldTagMatcherFields); err != nil {
 		return err
 	}
@@ -161,8 +161,17 @@ func (ft *fieldTagMatcher) UnmarshalJSON(bytes []byte) error {
 	if err := json.Unmarshal(bytes, &raw); err != nil {
 		return err
 	}
+
+	if raw.Key == "" {
+		return fmt.Errorf("invalid field tag matcher: please provide a non-empty Key")
+	}
+	if raw.Value == "" {
+		return fmt.Errorf("invalid field tag matcher: please provide a non-empty Value")
+	}
+
 	ft.Key = raw.Key
-	ft.Val = raw.Val
+	ft.Value = raw.Value
+
 	return nil
 }
 

internal/pkg/config/matcher_test.go

@@ -287,17 +287,43 @@ func TestFieldTagMatcherUnmarshalling(t *testing.T) {
 		desc, yaml string
 		wantErr    bool
 	}{
+		{
+			desc:    "missing value",
+			yaml:    "key: foo",
+			wantErr: true,
+		},
+		{
+			desc:    "missing key",
+			yaml:    "value: foo",
+			wantErr: true,
+		},
 		{
 			desc: "unknown field is not allowed",
 			yaml: `
 Key: good
+Value: good
 UnknownField: bad`,
 			wantErr: true,
-		}, {
-			desc: "valid field tag config",
+		},
+		{
+			desc: "val should be value",
 			yaml: `
 key: good
-val: AlsoGood`,
+val: "two letters short"`,
+			wantErr: true,
+		},
+		{
+			desc: "valid field tag config, lowercase",
+			yaml: `
+key: foo
+value: bar`,
+			wantErr: false,
+		},
+		{
+			desc: "valid field tag config, titlecase",
+			yaml: `
+Key: foo
+Value: bar`,
 			wantErr: false,
 		},
 	}

internal/pkg/config/testdata/test-config.yaml

@@ -20,7 +20,7 @@ sinks:
     receiverRE: "^Sinker$"
 fieldTags:
   - key: example
-    val: sensitive
+    value: sensitive
 exclude:
   - packageRE: "^example.com/exclusion$"
     methodRE: "^Foo$"

internal/pkg/fieldtags/testdata/test-config.yaml

@@ -14,4 +14,4 @@
 ---
 FieldTags:
   - Key: example
-    Val: sensitive
+    Value: sensitive