build: add fallback to outline requests if not supported by frontend

Signed-off-by: Tonis Tiigi <[email protected]>
docker · May 7, 2022 · 60c543a · 60c543a
1 parent b9995f5
commit 60c543a
Showing 1 changed file with 57 additions and 16 deletions.
diff --git a/build/build.go b/build/build.go
@@ -35,6 +35,7 @@ import (
 	gateway "github.com/moby/buildkit/frontend/gateway/client"
 	"github.com/moby/buildkit/session"
 	"github.com/moby/buildkit/session/upload/uploadprovider"
+	"github.com/moby/buildkit/solver/errdefs"
 	"github.com/moby/buildkit/solver/pb"
 	"github.com/moby/buildkit/util/apicaps"
 	"github.com/moby/buildkit/util/entitlements"
@@ -631,7 +632,7 @@ func Build(ctx context.Context, drivers []DriverInfo, opt map[string]Options, do
 		}
 	}
 
-	if noMobyDriver != nil && !noDefaultLoad() {
+	if noMobyDriver != nil && !noDefaultLoad() && noPrintFunc(opt) {
 		for _, opt := range opt {
 			if len(opt.Exports) == 0 {
 				logrus.Warnf("No output specified for %s driver. Build result will only remain in the build cache. To push result image into registry use --push or to load image into docker use --load", noMobyDriver.Factory().Name())
@@ -918,29 +919,60 @@ func Build(ctx context.Context, drivers []DriverInfo, opt map[string]Options, do
 						var printRes map[string][]byte
 
 						rr, err := c.Build(ctx, so, "buildx", func(ctx context.Context, c gateway.Client) (*gateway.Result, error) {
-							if opt.PrintFunc != "" {
-								if _, ok := req.FrontendOpt["frontend.caps"]; !ok {
-									req.FrontendOpt["frontend.caps"] = "moby.buildkit.frontend.subrequests+forward"
-								} else {
-									req.FrontendOpt["frontend.caps"] += ",moby.buildkit.frontend.subrequests+forward"
+							var isFallback bool
+							var origErr error
+							for {
+								if opt.PrintFunc != "" {
+									if _, ok := req.FrontendOpt["frontend.caps"]; !ok {
+										req.FrontendOpt["frontend.caps"] = "moby.buildkit.frontend.subrequests+forward"
+									} else {
+										req.FrontendOpt["frontend.caps"] += ",moby.buildkit.frontend.subrequests+forward"
+									}
+									req.FrontendOpt["requestid"] = "frontend." + opt.PrintFunc
+									if isFallback {
+										req.FrontendOpt["build-arg:BUILDKIT_SYNTAX"] = "docker/dockerfile-upstream:1.4-outline"
+									}
 								}
-								req.FrontendOpt["requestid"] = "frontend." + opt.PrintFunc
-							}
-							res, err := c.Solve(ctx, req)
-							if err != nil {
-								return nil, err
-							}
-							if opt.PrintFunc != "" {
-								printRes = res.Metadata
+								res, err := c.Solve(ctx, req)
+								if err != nil {
+									if origErr != nil {
+										return nil, err
+									}
+									var reqErr *errdefs.UnsupportedSubrequestError
+									if !isFallback {
+										if errors.As(err, &reqErr) {
+											switch reqErr.Name {
+											case "frontend.outline", "frontend.targets":
+												isFallback = true
+												origErr = err
+												continue
+											}
+											return nil, err
+										}
+										// buildkit v0.8 vendored in Docker 20.10 does not support typed errors
+										if strings.Contains(err.Error(), "unsupported request frontend.outline") || strings.Contains(err.Error(), "unsupported request frontend.targets") {
+											isFallback = true
+											origErr = err
+											continue
+										}
+									}
+									return nil, err
+								}
+								if opt.PrintFunc != "" {
+									printRes = res.Metadata
+								}
+								results.Set(resultKey(dp.driverIndex, k), res)
+								return res, nil
 							}
-							results.Set(resultKey(dp.driverIndex, k), res)
-							return res, nil
 						}, ch)
 						if err != nil {
 							return err
 						}
 						res[i] = rr
 
+						if rr.ExporterResponse == nil {
+							rr.ExporterResponse = map[string]string{}
+						}
 						for k, v := range printRes {
 							rr.ExporterResponse[k] = string(v)
 						}
@@ -1494,3 +1526,12 @@ func tryNodeIdentifier(configDir string) (out string) {
 	}
 	return
 }
+
+func noPrintFunc(opt map[string]Options) bool {
+	for _, v := range opt {
+		if v.PrintFunc != "" {
+			return false
+		}
+	}
+	return true
+}