feat: Initial support for Compose configs (#116)

pkg/client/compose/config.go

@@ -0,0 +1,75 @@
+package compose
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/compose-spec/compose-go/v2/types"
+	"github.com/psviderski/uncloud/pkg/api"
+)
+
+// TODO: add support for short syntax configs
+func configSpecsFromCompose(
+	configs types.Configs, serviceConfigs []types.ServiceConfigObjConfig, workingDir string,
+) ([]api.ConfigSpec, []api.ConfigMount, error) {
+	var configSpecs []api.ConfigSpec
+	var configMounts []api.ConfigMount
+
+	for _, serviceConfig := range serviceConfigs {
+		var spec api.ConfigSpec
+
+		if projectConfig, exists := configs[serviceConfig.Source]; exists {
+			if projectConfig.External {
+				return nil, nil, fmt.Errorf("external configs are not supported: %s",
+					serviceConfig.Source)
+			}
+
+			spec = api.ConfigSpec{
+				Name:    serviceConfig.Source,
+				Content: []byte(projectConfig.Content),
+			}
+
+			// If File is specified, read the file contents
+			if projectConfig.File != "" {
+				configPath := projectConfig.File
+				// TODO: handle this in a separate function?
+				if !filepath.IsAbs(configPath) {
+					configPath = filepath.Join(workingDir, configPath)
+				}
+
+				fileContent, err := os.ReadFile(configPath)
+				if err != nil {
+					return nil, nil, fmt.Errorf("read config from file '%s': %w", projectConfig.File, err)
+				}
+				spec.Content = fileContent
+			}
+		} else {
+			return nil, nil, fmt.Errorf("config '%s' not found in project configs", serviceConfig.Source)
+		}
+
+		configSpecs = append(configSpecs, spec)
+
+		// Create config mount
+		target := serviceConfig.Target
+		if target == "" {
+			target = "/" + serviceConfig.Source // Default mount path
+		}
+
+		mount := api.ConfigMount{
+			ConfigName:    spec.Name,
+			ContainerPath: target,
+			Uid:           serviceConfig.UID,
+			Gid:           serviceConfig.GID,
+		}
+
+		if serviceConfig.Mode != nil {
+			mode := os.FileMode(*serviceConfig.Mode)
+			mount.Mode = &mode
+		}
+
+		configMounts = append(configMounts, mount)
+	}
+
+	return configSpecs, configMounts, nil
+}