feat: support creating compose Stacks from Readers

compose.go

@@ -3,6 +3,7 @@ package testcontainers
 import (
 	"context"
 	"errors"
+	"io"
 	"path/filepath"
 	"runtime"
 	"strings"
@@ -92,6 +93,10 @@ func WithStackFiles(filePaths ...string) ComposeStackOption {
 	return ComposeStackFiles(filePaths)
 }
 
+func WithStackReaders(readers ...io.Reader) ComposeStackOption {
+	return ComposeStackReaders(readers)
+}
+
 func NewDockerCompose(filePaths ...string) (*dockerCompose, error) {
 	return NewDockerComposeWith(WithStackFiles(filePaths...))
 }

compose_api.go

@@ -3,6 +3,10 @@ package testcontainers
 import (
 	"context"
 	"fmt"
+	"hash/fnv"
+	"io"
+	"os"
+	"path/filepath"
 	"sort"
 	"strings"
 	"sync"
@@ -92,6 +96,45 @@ func (f StackIdentifier) String() string {
 	return string(f)
 }
 
+type ComposeStackReaders []io.Reader
+
+func (r ComposeStackReaders) applyToComposeStack(o *composeStackOptions) {
+	currentDir, err := os.Getwd()
+	if err != nil {
+		panic(err)
+	}
+
+	// choose directory to keep temporary files
+	// like
+	// 		/tmp/testcontainers-go/my-awesome-service-2f686f6d652f676f666f7262726f6b65
+	projectName := filepath.Base(currentDir)
+	projectHash := fmt.Sprintf("%x", fnv.New32a().Sum([]byte(currentDir)))[:32]
+	tmpDir := filepath.Join(os.TempDir(), "testcontainers-go", fmt.Sprintf("%s-%s", projectName, projectHash))
+	if err := os.RemoveAll(tmpDir); err != nil {
+		panic(err)
+	}
+	if err := os.MkdirAll(tmpDir, os.ModePerm); err != nil {
+		panic(err)
+	}
+
+	// write temporary files and put to files list
+	filePaths := make([]string, 0, len(r))
+	for idx, src := range r {
+		content, err := io.ReadAll(src)
+		if err != nil {
+			panic(err)
+		}
+		name := fmt.Sprintf("docker-compose-%d.yaml", idx)
+		filename := filepath.Join(tmpDir, name)
+		if err := os.WriteFile(filename, content, os.ModePerm); err != nil {
+			continue
+		}
+		filePaths = append(filePaths, filename)
+	}
+
+	o.Paths = filePaths
+}
+
 const (
 	// RemoveImagesAll - remove all images used by the stack
 	RemoveImagesAll RemoveImages = iota

compose_api_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"hash/fnv"
+	"strings"
 	"testing"
 	"time"
 
@@ -409,6 +410,48 @@ func TestDockerComposeApiWithWaitForShortLifespanService(t *testing.T) {
 	assert.Contains(t, services, "tzatziki")
 }
 
+func TestNewDockerComposeWithReaders(t *testing.T) {
+	var (
+		specOne = strings.NewReader(`
+version: "3"
+services:
+  nginx:
+    image: nginx:1.22.0-alpine
+`)
+		specTwo = strings.NewReader(`
+version: "3"
+services:
+  php:
+    image: php:8.1.7-alpine3.15
+`)
+		specTree = strings.NewReader(`
+version: "3"
+services:
+  redis:
+    image: redis:alpine3.15
+`)
+	)
+	compose, err := NewDockerComposeWith(WithStackReaders(specOne, specTwo, specTree))
+	assert.NoError(t, err, "NewDockerComposeWith(WithStackReaders(...))")
+	assert.Equal(t, 3, len(compose.configs))
+
+	t.Cleanup(func() {
+		assert.NoError(t, compose.Down(context.Background(), RemoveOrphans(true), RemoveImagesLocal), "compose.Down()")
+	})
+
+	ctx, cancel := context.WithCancel(context.Background())
+	t.Cleanup(cancel)
+
+	err = compose.Up(ctx)
+	assert.NoError(t, err, "compose.Up()")
+
+	serviceNames := compose.Services()
+	assert.Equal(t, 3, len(serviceNames))
+	assert.Contains(t, serviceNames, "nginx")
+	assert.Contains(t, serviceNames, "php")
+	assert.Contains(t, serviceNames, "redis")
+}
+
 func testNameHash(name string) StackIdentifier {
 	return StackIdentifier(fmt.Sprintf("%x", fnv.New32a().Sum([]byte(name))))
 }