Analytics: implement impact analysis

This analysis provides inside into which layer/document get affected if
given set of keys is 'touched'

Signed-off-by: Richard Kosegi <richard.kosegi@gmail.com>

analytics/common_test.go

@@ -16,6 +16,13 @@ limitations under the License.
 
 package analytics
 
+import (
+	"github.com/rkosegi/yaml-toolkit/dom"
+	"github.com/stretchr/testify/assert"
+	"strings"
+	"testing"
+)
+
 type testDocsData struct {
 	doc  string
 	tags []string
@@ -77,3 +84,9 @@ defaults:
 		},
 	}
 )
+
+func loadDocsIntoSet(t *testing.T, ds DocumentSet) {
+	for k, v := range testDocSrc {
+		assert.NoError(t, ds.AddDocumentFromReader(k, strings.NewReader(v.doc), dom.DefaultYamlDecoder, WithTags(v.tags...)))
+	}
+}

analytics/dependency_resolver_test.go

@@ -23,26 +23,6 @@ import (
 	"testing"
 )
 
-func srcDoc(t *testing.T) dom.ContainerBuilder {
-	c, err := b.FromReader(strings.NewReader(`
----
-server:
-  port: ${env.server.port}
-client:
-  url: ${env.client.url}
-default:
-  port: 8080
-`), dom.DefaultYamlDecoder)
-	assert.NoError(t, err)
-	return c
-}
-
-func loadDocsIntoSet(t *testing.T, ds DocumentSet) {
-	for k, v := range testDocSrc {
-		assert.NoError(t, ds.AddDocumentFromReader(k, strings.NewReader(v.doc), dom.DefaultYamlDecoder, WithTags(v.tags...)))
-	}
-}
-
 func TestDefaultDependencyResolver(t *testing.T) {
 	ds := NewDocumentSet()
 	loadDocsIntoSet(t, ds)

analytics/impact_analysis.go

@@ -0,0 +1,88 @@
+/*
+Copyright 2024 Richard Kosegi
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package analytics
+
+import (
+	"github.com/rkosegi/yaml-toolkit/dom"
+)
+
+type ImpactAnalysis interface {
+	ResolveOverlayDocument(od dom.OverlayDocument, keys []string) map[string]dom.Coordinates
+	ResolveDocumentSet(ds DocumentSet, keys []string) map[string]dom.Coordinates
+}
+
+type impactAnalysis struct {
+	keyFilterFn          StringPredicateFn
+	placeholderMatcherFn func(string) dom.SearchValueFunc
+}
+
+func (i *impactAnalysis) ResolveDocumentSet(ds DocumentSet, keys []string) map[string]dom.Coordinates {
+	return i.ResolveOverlayDocument(ds.AsOne(), keys)
+}
+
+func (i *impactAnalysis) resolveKey(od dom.OverlayDocument, key string) dom.Coordinates {
+	if x := od.Search(i.placeholderMatcherFn(key)); x != nil {
+		return x
+	}
+	return nil
+}
+
+func (i *impactAnalysis) ResolveOverlayDocument(od dom.OverlayDocument, keys []string) map[string]dom.Coordinates {
+	res := make(map[string]dom.Coordinates)
+	for _, key := range keys {
+		r := i.resolveKey(od, key)
+		if r != nil {
+			res[key] = r
+		}
+	}
+	return res
+}
+
+type ImpactAnalysisBuilder interface {
+	Build() ImpactAnalysis
+	// WithKeyFilter allows to override default key filter predicate
+	WithKeyFilter(StringPredicateFn) ImpactAnalysisBuilder
+}
+
+type impactAnalysisBuilder struct {
+	// method to override dom.SearchValueFunc which searches property value for presence of placeholder reference.
+	placeholderMatcherFn func(string) dom.SearchValueFunc
+	keyFilterFn          StringPredicateFn
+}
+
+func (iab *impactAnalysisBuilder) WithKeyFilter(keyFilterFn StringPredicateFn) ImpactAnalysisBuilder {
+	iab.keyFilterFn = keyFilterFn
+	return iab
+}
+
+// Build builds new instance of ImpactAnalysis using current state of builder.
+// It's safe to call any builder method after Build() has been called, it won't affect existing builders,
+// only newly created called afterward
+func (iab *impactAnalysisBuilder) Build() ImpactAnalysis {
+	return &impactAnalysis{
+		placeholderMatcherFn: iab.placeholderMatcherFn,
+		keyFilterFn:          iab.keyFilterFn,
+	}
+}
+
+// NewImpactAnalysisBuilder returns new instance of ImpactAnalysisBuilder with default values set
+func NewImpactAnalysisBuilder() ImpactAnalysisBuilder {
+	return &impactAnalysisBuilder{
+		placeholderMatcherFn: hasPlaceholderFunc,
+		keyFilterFn:          matchAll,
+	}
+}

analytics/impact_analysis_test.go

@@ -0,0 +1,39 @@
+/*
+Copyright 2024 Richard Kosegi
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package analytics
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestAnalyseImpact(t *testing.T) {
+	ds := NewDocumentSet()
+	loadDocsIntoSet(t, ds)
+	ia := NewImpactAnalysisBuilder().
+		WithKeyFilter(matchAll).
+		Build()
+
+	res := ia.ResolveDocumentSet(ds, []string{
+		"env.port",
+		"defaults.connection.retryCount",
+		"unknown.invalid.key",
+	})
+
+	assert.Equal(t, 2, len(res))
+	assert.Equal(t, 1, len(res["env.port"]))
+}