Omit go.{mod,sum} from pkg when not in module mode

In certain environments, it's possible to package chaincode that
structured as a module from an active GOPATH. This often happens when
the path provided to the package command is an import path resolvable
from the GOPATH instead of a file system path.

If the package could be successfully built in the packaging environment
using the import path, the chaincode dependencies would be calculated
and packaged from the GOPATH for compilation as a traditional go
package.

In this scenario, the `go.mod` would be included in the chaincode
package as packaging always includes all non-hidden files in the top
level folder of the import path.

On the server, the presence of the `go.mod` implies that the build
process should execute in module mode. When the dependencies have been
vendored in the module, the build uses `-mod=vendor` flag to indicate
the module requirements should be satisfied from the vendor folder.
Unfortunately, since the chaincode dependencies were packaged using
GOPATH mode instead of module mode, there are some metadata files
missing from the vendor folder that are expected by the module mode
build process.

To help prevent this from occuring, we will explicitly omit go.mod and
go.sum from top level folder of chaincode that is not packaged in module
mode.

FAB-17725

Signed-off-by: Matthew Sykes <sykesmat@us.ibm.com>
Change-Id: I5253205ab9c7471beddffec7a11dab987c3acebd

core/chaincode/platforms/golang/platform.go

@@ -290,7 +290,7 @@ func DescribeCode(path string) (*CodeDescriptor, error) {
 func describeGopath(importPath string) (*CodeDescriptor, error) {
 	output, err := exec.Command("go", "list", "-f", "{{.Dir}}", importPath).Output()
 	if err != nil {
-		return nil, err
+		return nil, wrapExitErr(err, "'go list' failed")
 	}
 	sourcePath := filepath.Clean(strings.TrimSpace(string(output)))
 
@@ -336,7 +336,7 @@ func moduleInfo(path string) (*ModuleInfo, error) {
 	cmd.Env = append(os.Environ(), "GO111MODULE=on")
 	output, err := cmd.Output()
 	if err != nil {
-		return nil, errors.Wrap(err, "failed to determine module root")
+		return nil, wrapExitErr(err, "failed to determine module root")
 	}
 
 	modExists, err := regularFileExists(strings.TrimSpace(string(output)))
@@ -445,6 +445,10 @@ func findSource(cd *CodeDescriptor) (SourceMap, error) {
 		case cd.Module:
 			name = filepath.Join("src", name)
 		default:
+			// skip top level go.mod and go.sum when not in module mode
+			if name == "go.mod" || name == "go.sum" {
+				return nil
+			}
 			name = filepath.Join("src", cd.Path, name)
 		}
 

core/chaincode/platforms/golang/platform_test.go

@@ -177,14 +177,17 @@ func getGopath() (string, error) {
 func Test_findSource(t *testing.T) {
 	t.Run("Gopath", func(t *testing.T) {
 		source, err := findSource(&CodeDescriptor{
+			Module:       false,
 			Source:       filepath.FromSlash("testdata/src/chaincodes/noop"),
 			MetadataRoot: filepath.FromSlash("testdata/src/chaincodes/noop/META-INF"),
 			Path:         "chaincodes/noop",
 		})
 		require.NoError(t, err, "failed to find source")
-		assert.Len(t, source, 2)
 		assert.Contains(t, source, "src/chaincodes/noop/chaincode.go")
 		assert.Contains(t, source, "META-INF/statedb/couchdb/indexes/indexOwner.json")
+		assert.NotContains(t, source, "src/chaincodes/noop/go.mod")
+		assert.NotContains(t, source, "src/chaincodes/noop/go.sum")
+		assert.Len(t, source, 2)
 	})
 
 	t.Run("Module", func(t *testing.T) {
@@ -463,6 +466,24 @@ func TestDescribeCode(t *testing.T) {
 	})
 }
 
+func TestRegularFileExists(t *testing.T) {
+	t.Run("RegularFile", func(t *testing.T) {
+		ok, err := regularFileExists("testdata/ccmodule/go.mod")
+		assert.NoError(t, err)
+		assert.True(t, ok)
+	})
+	t.Run("MissingFile", func(t *testing.T) {
+		ok, err := regularFileExists("testdata/missing.file")
+		assert.NoError(t, err)
+		assert.False(t, ok)
+	})
+	t.Run("Directory", func(t *testing.T) {
+		ok, err := regularFileExists("testdata")
+		assert.NoError(t, err)
+		assert.False(t, ok)
+	})
+}
+
 func TestMain(m *testing.M) {
 	viper.SetConfigName("core")
 	viper.SetEnvPrefix("CORE")

core/chaincode/platforms/golang/testdata/src/chaincodes/noop/go.mod

@@ -0,0 +1,5 @@
+module github.com/hyperledger/fabric/core/chaincode/platforms/golang/testdata/src/chaincodes/noop
+
+go 1.13
+
+// This should not get included in packages that were created from a GOPATH

core/chaincode/platforms/golang/testdata/src/chaincodes/noop/go.sum

@@ -0,0 +1,2 @@
+ignore/me v0.0.1 h1:0badc0de0badcode
+ignore/me v0.0.1/go.mod