[shell-operator] chore: reduce memory consumption (#871)

Signed-off-by: Pavel Okhlopkov <pavel.okhlopkov@flant.com>

Author: ldmonster

pkg/executor/executor.go

@@ -215,7 +215,7 @@ func (pl *proxyLogger) Write(p []byte) (int, error) {
 
 	logMap, ok := line.(map[string]interface{})
 	defer func() {
-		pl.buf = []byte{}
+		pl.buf = pl.buf[:0]
 	}()
 
 	if !ok {

pkg/filter/jq/apply.go

@@ -3,6 +3,7 @@ package jq
 import (
 	"encoding/json"
 	"errors"
+	"fmt"
 
 	"github.com/itchyny/gojq"
 
@@ -91,19 +92,48 @@ func (c *CompiledJqFilter) String() string {
 	return c.originalStr
 }
 
+// deepCopyAny recursively copies JSON-compatible values (maps, slices, and
+// primitives) without going through json.Marshal/Unmarshal. This is
+// significantly faster and allocates only the final structure.
 func deepCopyAny(input any) (any, error) {
 	if input == nil {
 		return nil, nil
 	}
-	data, err := json.Marshal(input)
-	if err != nil {
-		return nil, err
-	}
-	var output any
-	if err := json.Unmarshal(data, &output); err != nil {
-		return nil, err
+	return deepCopyValue(input)
+}
+
+func deepCopyValue(v any) (any, error) {
+	switch val := v.(type) {
+	case map[string]any:
+		m := make(map[string]any, len(val))
+		for k, v := range val {
+			copied, err := deepCopyValue(v)
+			if err != nil {
+				return nil, err
+			}
+			m[k] = copied
+		}
+		return m, nil
+	case []any:
+		s := make([]any, len(val))
+		for i, v := range val {
+			copied, err := deepCopyValue(v)
+			if err != nil {
+				return nil, err
+			}
+			s[i] = copied
+		}
+		return s, nil
+	case string, bool, json.Number,
+		int, int8, int16, int32, int64,
+		uint, uint8, uint16, uint32, uint64,
+		float32, float64:
+		return val, nil
+	case nil:
+		return nil, nil
+	default:
+		return nil, fmt.Errorf("deepCopyValue: unsupported type %T", v)
 	}
-	return output, nil
 }
 
 // collectResults drains a gojq iterator and serialises the results to JSON.

pkg/filter/jq/apply_test.go

@@ -175,32 +175,114 @@ func Test_ApplyFilter_PanicSafety(t *testing.T) {
 func Test_deepCopyAny(t *testing.T) {
 	g := NewWithT(t)
 
-	// Test copying a map
+	// Test copying a map preserves types
 	inputMap := map[string]any{"foo": "bar", "num": 42}
 	copyMap, err := deepCopyAny(inputMap)
 	g.Expect(err).Should(BeNil())
-	g.Expect(copyMap).Should(Equal(map[string]any{"foo": "bar", "num": float64(42)}))
+	g.Expect(copyMap).Should(Equal(map[string]any{"foo": "bar", "num": 42}))
 	g.Expect(copyMap).ShouldNot(BeIdenticalTo(inputMap))
 
-	// Test copying a slice
+	// Test copying a slice preserves types
 	inputSlice := []any{"a", 1, true}
 	copySlice, err := deepCopyAny(inputSlice)
 	g.Expect(err).Should(BeNil())
-	g.Expect(copySlice).Should(Equal([]any{"a", float64(1), true}))
+	g.Expect(copySlice).Should(Equal([]any{"a", 1, true}))
 	g.Expect(copySlice).ShouldNot(BeIdenticalTo(inputSlice))
 
 	// Test copying nil
 	copyNil, err := deepCopyAny(nil)
 	g.Expect(err).Should(BeNil())
 	g.Expect(copyNil).Should(BeNil())
 
-	// Test copying a value that cannot be marshaled to JSON
+	// Test copying a value with unsupported type
 	inputInvalid := map[string]any{"ch": make(chan int)}
 	copyInvalid, err := deepCopyAny(inputInvalid)
 	g.Expect(err).ShouldNot(BeNil())
 	g.Expect(copyInvalid).Should(BeNil())
 }
 
+func Test_deepCopyAny_NestedMap(t *testing.T) {
+	g := NewWithT(t)
+
+	input := map[string]any{
+		"metadata": map[string]any{
+			"name":      "my-pod",
+			"namespace": "default",
+			"labels":    map[string]any{"app": "test"},
+		},
+		"spec": map[string]any{
+			"replicas": float64(3),
+		},
+	}
+
+	result, err := deepCopyAny(input)
+	g.Expect(err).Should(BeNil())
+
+	resultMap := result.(map[string]any)
+	g.Expect(resultMap["metadata"]).Should(Equal(input["metadata"]))
+
+	// Verify it's a true deep copy: mutating the copy must not affect the original.
+	resultMeta := resultMap["metadata"].(map[string]any)
+	resultMeta["name"] = "mutated"
+	g.Expect(input["metadata"].(map[string]any)["name"]).Should(Equal("my-pod"))
+}
+
+func Test_deepCopyAny_NestedSlice(t *testing.T) {
+	g := NewWithT(t)
+
+	input := []any{
+		map[string]any{"name": "a"},
+		map[string]any{"name": "b"},
+	}
+
+	result, err := deepCopyAny(input)
+	g.Expect(err).Should(BeNil())
+
+	resultSlice := result.([]any)
+	g.Expect(resultSlice).Should(HaveLen(2))
+
+	// Mutate copy, verify original is untouched.
+	resultSlice[0].(map[string]any)["name"] = "mutated"
+	g.Expect(input[0].(map[string]any)["name"]).Should(Equal("a"))
+}
+
+func Test_deepCopyAny_NumericTypes(t *testing.T) {
+	g := NewWithT(t)
+
+	input := map[string]any{
+		"int":     42,
+		"int64":   int64(100),
+		"float64": 3.14,
+		"bool":    true,
+		"string":  "hello",
+	}
+
+	result, err := deepCopyAny(input)
+	g.Expect(err).Should(BeNil())
+	g.Expect(result).Should(Equal(input))
+}
+
+func BenchmarkDeepCopyAny(b *testing.B) {
+	input := map[string]any{
+		"metadata": map[string]any{
+			"name":      "my-pod",
+			"namespace": "default",
+			"labels":    map[string]any{"app": "test", "env": "prod"},
+		},
+		"spec": map[string]any{
+			"containers": []any{
+				map[string]any{"name": "main", "image": "nginx:latest"},
+				map[string]any{"name": "sidecar", "image": "envoy:latest"},
+			},
+			"replicas": float64(3),
+		},
+	}
+	b.ResetTimer()
+	for range b.N {
+		_, _ = deepCopyAny(input)
+	}
+}
+
 // ---- Compile / CompiledJqFilter tests ----
 
 func Test_Compile_ValidExpression(t *testing.T) {

pkg/hook/binding_context/binding_context.go

@@ -2,6 +2,7 @@ package bindingcontext
 
 import (
 	"encoding/json"
+	"io"
 
 	"github.com/deckhouse/deckhouse/pkg/log"
 	v1 "k8s.io/api/admission/v1"
@@ -182,6 +183,13 @@ func ConvertBindingContextList(version string, contexts []BindingContext) Bindin
 }
 
 func (b BindingContextList) Json() ([]byte, error) {
-	data, err := json.MarshalIndent(b, "", "  ")
-	return data, err
+	return json.Marshal(b)
+}
+
+// WriteJson streams the JSON-encoded binding context list directly to w,
+// avoiding an intermediate []byte allocation that can be very large for
+// synchronization events with many objects.
+func (b BindingContextList) WriteJson(w io.Writer) error {
+	enc := json.NewEncoder(w)
+	return enc.Encode(b)
 }