bake: fix output handling for push and load

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

bake/bake.go

@@ -898,14 +898,36 @@ func (t *Target) AddOverrides(overrides map[string]Override) error {
 			if err != nil {
 				return errors.Errorf("invalid value %s for boolean key push", value)
 			}
-			if len(t.Outputs) == 0 {
-				t.Outputs = append(t.Outputs, "type=image,push=true")
-			} else {
-				for i, output := range t.Outputs {
-					if typ := parseOutputType(output); typ == "image" || typ == "registry" {
-						t.Outputs[i] = t.Outputs[i] + ",push=" + value
+			var pushUsed bool
+			for i, output := range t.Outputs {
+				if typ := parseOutputType(output); typ == "image" || typ == "registry" {
+					t.Outputs[i] = t.Outputs[i] + ",push=" + value
+					pushUsed = true
+				}
+			}
+			if !pushUsed {
+				t.Outputs = append(t.Outputs, "type=image,push="+value)
+			}
+		case "load":
+			load, err := strconv.ParseBool(value)
+			if err != nil {
+				return errors.Errorf("invalid value %s for boolean key load", value)
+			}
+			if load {
+				var loadUsed bool
+				for _, output := range t.Outputs {
+					if typ := parseOutputType(output); typ == "docker" {
+						if v := parseOutput(output); v != nil {
+							if _, ok := v["dest"]; !ok {
+								loadUsed = true
+								break
+							}
+						}
 					}
 				}
+				if !loadUsed {
+					t.Outputs = append(t.Outputs, "type=docker")
+				}
 			}
 		default:
 			return errors.Errorf("unknown key: %s", keys[0])
@@ -1394,18 +1416,26 @@ func removeAttestDupes(s []string) []string {
 	return res
 }
 
-func parseOutputType(str string) string {
+func parseOutput(str string) map[string]string {
 	csvReader := csv.NewReader(strings.NewReader(str))
 	fields, err := csvReader.Read()
 	if err != nil {
-		return ""
+		return nil
 	}
+	res := map[string]string{}
 	for _, field := range fields {
 		parts := strings.SplitN(field, "=", 2)
 		if len(parts) == 2 {
-			if parts[0] == "type" {
-				return parts[1]
-			}
+			res[parts[0]] = parts[1]
+		}
+	}
+	return res
+}
+
+func parseOutputType(str string) string {
+	if out := parseOutput(str); out != nil {
+		if v, ok := out["type"]; ok {
+			return v
 		}
 	}
 	return ""

commands/bake.go

@@ -72,10 +72,10 @@ func runBake(ctx context.Context, dockerCli command.Cli, targets []string, in ba
 
 	overrides := in.overrides
 	if in.exportPush {
-		overrides = append(overrides, "*.output=type=registry")
+		overrides = append(overrides, "*.push=true")
 	}
 	if in.exportLoad {
-		overrides = append(overrides, "*.output=type=docker")
+		overrides = append(overrides, "*.load=true")
 	}
 	if cFlags.noCache != nil {
 		overrides = append(overrides, fmt.Sprintf("*.no-cache=%t", *cFlags.noCache))

docs/reference/buildx_bake.md

@@ -162,6 +162,7 @@ You can override the following fields:
 * `context`
 * `dockerfile`
 * `labels`
+* `load`
 * `no-cache`
 * `no-cache-filter`
 * `output`