Allow importing compose file to override resource definition

Signed-off-by: Nicolas De Loof <nicolas.deloof@gmail.com>

Author: ndeloof

loader/include.go

@@ -21,11 +21,12 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
-	"reflect"
 	"strings"
 
 	"github.com/compose-spec/compose-go/v2/dotenv"
 	interp "github.com/compose-spec/compose-go/v2/interpolation"
+	"github.com/compose-spec/compose-go/v2/override"
+	"github.com/compose-spec/compose-go/v2/tree"
 	"github.com/compose-spec/compose-go/v2/types"
 )
 
@@ -50,7 +51,7 @@ func loadIncludeConfig(source any) ([]types.IncludeConfig, error) {
 	return requires, err
 }
 
-func ApplyInclude(ctx context.Context, workingDir string, environment types.Mapping, model map[string]any, options *Options, included []string) error {
+func ApplyInclude(ctx context.Context, workingDir string, environment types.Mapping, model map[string]any, options *Options, included []string, processor PostProcessor) error {
 	includeConfig, err := loadIncludeConfig(model["include"])
 	if err != nil {
 		return err
@@ -154,7 +155,7 @@ func ApplyInclude(ctx context.Context, workingDir string, environment types.Mapp
 		if err != nil {
 			return err
 		}
-		err = importResources(imported, model)
+		err = importResources(imported, model, processor)
 		if err != nil {
 			return err
 		}
@@ -164,29 +165,29 @@ func ApplyInclude(ctx context.Context, workingDir string, environment types.Mapp
 }
 
 // importResources import into model all resources defined by imported, and report error on conflict
-func importResources(source map[string]any, target map[string]any) error {
-	if err := importResource(source, target, "services"); err != nil {
+func importResources(source map[string]any, target map[string]any, processor PostProcessor) error {
+	if err := importResource(source, target, "services", processor); err != nil {
 		return err
 	}
-	if err := importResource(source, target, "volumes"); err != nil {
+	if err := importResource(source, target, "volumes", processor); err != nil {
 		return err
 	}
-	if err := importResource(source, target, "networks"); err != nil {
+	if err := importResource(source, target, "networks", processor); err != nil {
 		return err
 	}
-	if err := importResource(source, target, "secrets"); err != nil {
+	if err := importResource(source, target, "secrets", processor); err != nil {
 		return err
 	}
-	if err := importResource(source, target, "configs"); err != nil {
+	if err := importResource(source, target, "configs", processor); err != nil {
 		return err
 	}
-	if err := importResource(source, target, "models"); err != nil {
+	if err := importResource(source, target, "models", processor); err != nil {
 		return err
 	}
 	return nil
 }
 
-func importResource(source map[string]any, target map[string]any, key string) error {
+func importResource(source map[string]any, target map[string]any, key string, processor PostProcessor) error {
 	from := source[key]
 	if from != nil {
 		var to map[string]any
@@ -196,13 +197,25 @@ func importResource(source map[string]any, target map[string]any, key string) er
 			to = map[string]any{}
 		}
 		for name, a := range from.(map[string]any) {
-			if conflict, ok := to[name]; ok {
-				if reflect.DeepEqual(a, conflict) {
-					continue
-				}
-				return fmt.Errorf("%s.%s conflicts with imported resource", key, name)
+			conflict, ok := to[name]
+			if !ok {
+				to[name] = a
+				continue
+			}
+			err := processor.Apply(map[string]any{
+				key: map[string]any{
+					name: a,
+				},
+			})
+			if err != nil {
+				return err
+			}
+
+			merged, err := override.MergeYaml(a, conflict, tree.NewPath(key, name))
+			if err != nil {
+				return err
 			}
-			to[name] = a
+			to[name] = merged
 		}
 		target[key] = to
 	}

loader/include_test.go

@@ -81,12 +81,21 @@ include:
 services:
   bar:
     image: busybox
+    environment: !override
+      - ZOT=QIX
 `, map[string]string{"SOURCE": "override"})
-	_, err := LoadWithContext(context.TODO(), details, func(options *Options) {
+	p, err := LoadWithContext(context.TODO(), details, func(options *Options) {
 		options.SkipNormalization = true
 		options.ResolvePaths = true
 	})
-	assert.ErrorContains(t, err, "services.bar conflicts with imported resource", err)
+	assert.NilError(t, err)
+	assert.DeepEqual(t, p.Services["bar"], types.ServiceConfig{
+		Name:  "bar",
+		Image: "busybox",
+		Environment: types.MappingWithEquals{
+			"ZOT": strPtr("QIX"),
+		},
+	})
 }
 
 func TestIncludeRelative(t *testing.T) {

loader/loader.go

@@ -459,7 +459,7 @@ func loadYamlFile(ctx context.Context,
 
 		if !opts.SkipInclude {
 			included = append(included, file.Filename)
-			err = ApplyInclude(ctx, workingDir, environment, cfg, opts, included)
+			err = ApplyInclude(ctx, workingDir, environment, cfg, opts, included, processor)
 			if err != nil {
 				return err
 			}

loader/testdata/compose-include.yaml

@@ -3,4 +3,6 @@ include:
 
 services:
   bar:
-    image: bar
+    image: bar
+    environment:
+      - FOO=BAR

override/extends.go

@@ -19,7 +19,7 @@ package override
 import "github.com/compose-spec/compose-go/v2/tree"
 
 func ExtendService(base, override map[string]any) (map[string]any, error) {
-	yaml, err := mergeYaml(base, override, tree.NewPath("services.x"))
+	yaml, err := MergeYaml(base, override, tree.NewPath("services.x"))
 	if err != nil {
 		return nil, err
 	}

override/merge.go

@@ -26,7 +26,7 @@ import (
 
 // Merge applies overrides to a config model
 func Merge(right, left map[string]any) (map[string]any, error) {
-	merged, err := mergeYaml(right, left, tree.NewPath())
+	merged, err := MergeYaml(right, left, tree.NewPath())
 	if err != nil {
 		return nil, err
 	}
@@ -70,8 +70,8 @@ func init() {
 	mergeSpecials["services.*.ulimits.*"] = mergeUlimit
 }
 
-// mergeYaml merges map[string]any yaml trees handling special rules
-func mergeYaml(e any, o any, p tree.Path) (any, error) {
+// MergeYaml merges map[string]any yaml trees handling special rules
+func MergeYaml(e any, o any, p tree.Path) (any, error) {
 	for pattern, merger := range mergeSpecials {
 		if p.Matches(pattern) {
 			merged, err := merger(e, o, p)
@@ -110,7 +110,7 @@ func mergeMappings(mapping map[string]any, other map[string]any, p tree.Path) (m
 			continue
 		}
 		next := p.Next(k)
-		merged, err := mergeYaml(e, v, next)
+		merged, err := MergeYaml(e, v, next)
 		if err != nil {
 			return nil, err
 		}