add -protoset-out option (#120)

cmd/grpcurl/grpcurl.go

@@ -52,13 +52,22 @@ var (
 	key = flags.String("key", "", prettify(`
 		File containing client private key, to present to the server. Not valid
 		with -plaintext option. Must also provide -cert option.`))
-	protoset    multiString
-	protoFiles  multiString
-	importPaths multiString
-	addlHeaders multiString
-	rpcHeaders  multiString
-	reflHeaders multiString
-	authority   = flags.String("authority", "", prettify(`
+	protoset      multiString
+	protoFiles    multiString
+	importPaths   multiString
+	addlHeaders   multiString
+	rpcHeaders    multiString
+	reflHeaders   multiString
+	expandHeaders = flags.Bool("expand-headers", false, prettify(`
+		If set, headers may use '${NAME}' syntax to reference environment
+		variables. These will be expanded to the actual environment variable
+		value before sending to the server. For example, if there is an
+		environment variable defined like FOO=bar, then a header of
+		'key: ${FOO}' would expand to 'key: bar'. This applies to -H,
+		-rpc-header, and -reflect-header options. No other expansion/escaping is
+		performed. This can be used to supply credentials/secrets without having
+		to put them in command-line arguments.`))
+	authority = flags.String("authority", "", prettify(`
 		Value of :authority pseudo-header to be use with underlying HTTP/2
 		requests. It defaults to the given address.`))
 	data = flags.String("d", "", prettify(`
@@ -93,6 +102,13 @@ var (
 		will accept. If not specified, defaults to 4,194,304 (4 megabytes).`))
 	emitDefaults = flags.Bool("emit-defaults", false, prettify(`
 		Emit default values for JSON-encoded responses.`))
+	protosetOut = flags.String("protoset-out", "", prettify(`
+		The name of a file to be written that will contain a FileDescriptorSet
+		proto. With the list and describe verbs, the listed or described
+		elements and their transitive dependencies will be written to the named
+		file if this option is given. When invoking an RPC and this option is
+		given, the method being invoked and its transitive dependencies will be
+		included in the output file.`))
 	msgTemplate = flags.Bool("msg-template", false, prettify(`
 		When describing messages, show a template of input data.`))
 	verbose = flags.Bool("v", false, prettify(`
@@ -313,6 +329,22 @@ func main() {
 		return cc
 	}
 
+	if *expandHeaders {
+		var err error
+		addlHeaders, err = grpcurl.ExpandHeaders(addlHeaders)
+		if err != nil {
+			fail(err, "Failed to expand additional headers")
+		}
+		rpcHeaders, err = grpcurl.ExpandHeaders(rpcHeaders)
+		if err != nil {
+			fail(err, "Failed to expand rpc headers")
+		}
+		reflHeaders, err = grpcurl.ExpandHeaders(reflHeaders)
+		if err != nil {
+			fail(err, "Failed to expand reflection headers")
+		}
+	}
+
 	var cc *grpc.ClientConn
 	var descSource grpcurl.DescriptorSource
 	var refClient *grpcreflect.Client
@@ -367,6 +399,9 @@ func main() {
 					fmt.Printf("%s\n", svc)
 				}
 			}
+			if err := writeProtoset(descSource, svcs...); err != nil {
+				fail(err, "Failed to write protoset to %s", *protosetOut)
+			}
 		} else {
 			methods, err := grpcurl.ListMethods(descSource, symbol)
 			if err != nil {
@@ -379,6 +414,9 @@ func main() {
 					fmt.Printf("%s\n", m)
 				}
 			}
+			if err := writeProtoset(descSource, symbol); err != nil {
+				fail(err, "Failed to write protoset to %s", *protosetOut)
+			}
 		}
 
 	} else if describe {
@@ -479,6 +517,9 @@ func main() {
 				fmt.Println(str)
 			}
 		}
+		if err := writeProtoset(descSource, symbols...); err != nil {
+			fail(err, "Failed to write protoset to %s", *protosetOut)
+		}
 
 	} else {
 		// Invoke an RPC
@@ -595,3 +636,15 @@ func fail(err error, msg string, args ...interface{}) {
 		exit(2)
 	}
 }
+
+func writeProtoset(descSource grpcurl.DescriptorSource, symbols ...string) error {
+	if *protosetOut == "" {
+		return nil
+	}
+	f, err := os.Create(*protosetOut)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	return grpcurl.WriteProtoset(f, descSource, symbols...)
+}

desc_source.go

@@ -3,6 +3,7 @@ package grpcurl
 import (
 	"errors"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"sync"
 
@@ -251,3 +252,53 @@ func reflectionSupport(err error) error {
 	}
 	return err
 }
+
+// WriteProtoset will use the given descriptor source to resolve all of the given
+// symbols and write a proto file descriptor set with their definitions to the
+// given output. The output will include descriptors for all files in which the
+// symbols are defined as well as their transitive dependencies.
+func WriteProtoset(out io.Writer, descSource DescriptorSource, symbols ...string) error {
+	// compute set of file descriptors
+	filenames := make([]string, 0, len(symbols))
+	fds := make(map[string]*desc.FileDescriptor, len(symbols))
+	for _, sym := range symbols {
+		d, err := descSource.FindSymbol(sym)
+		if err != nil {
+			return fmt.Errorf("failed to find descriptor for %q: %v", sym, err)
+		}
+		fd := d.GetFile()
+		if _, ok := fds[fd.GetName()]; !ok {
+			fds[fd.GetName()] = fd
+			filenames = append(filenames, fd.GetName())
+		}
+	}
+	// now expand that to include transitive dependencies in topologically sorted
+	// order (such that file always appears after its dependencies)
+	expandedFiles := make(map[string]struct{}, len(fds))
+	allFilesSlice := make([]*descpb.FileDescriptorProto, 0, len(fds))
+	for _, filename := range filenames {
+		allFilesSlice = addFilesToSet(allFilesSlice, expandedFiles, fds[filename])
+	}
+	// now we can serialize to file
+	b, err := proto.Marshal(&descpb.FileDescriptorSet{File: allFilesSlice})
+	if err != nil {
+		return fmt.Errorf("failed to serialize file descriptor set: %v", err)
+	}
+	if _, err := out.Write(b); err != nil {
+		return fmt.Errorf("failed to write file descriptor set: %v", err)
+	}
+	return nil
+}
+
+func addFilesToSet(allFiles []*descpb.FileDescriptorProto, expanded map[string]struct{}, fd *desc.FileDescriptor) []*descpb.FileDescriptorProto {
+	if _, ok := expanded[fd.GetName()]; ok {
+		// already seen this one
+		return allFiles
+	}
+	expanded[fd.GetName()] = struct{}{}
+	// add all dependencies first
+	for _, dep := range fd.GetDependencies() {
+		allFiles = addFilesToSet(allFiles, expanded, dep)
+	}
+	return append(allFiles, fd.AsFileDescriptorProto())
+}

desc_source_test.go

@@ -0,0 +1,62 @@
+package grpcurl
+
+import (
+	"bytes"
+	"io/ioutil"
+	"testing"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/golang/protobuf/protoc-gen-go/descriptor"
+)
+
+func TestWriteProtoset(t *testing.T) {
+	exampleProtoset, err := loadProtoset("./testing/example.protoset")
+	if err != nil {
+		t.Fatalf("failed to load example.protoset: %v", err)
+	}
+	testProtoset, err := loadProtoset("./testing/test.protoset")
+	if err != nil {
+		t.Fatalf("failed to load test.protoset: %v", err)
+	}
+
+	mergedProtoset := &descriptor.FileDescriptorSet{
+		File: append(exampleProtoset.File, testProtoset.File...),
+	}
+
+	descSrc, err := DescriptorSourceFromFileDescriptorSet(mergedProtoset)
+	if err != nil {
+		t.Fatalf("failed to create descriptor source: %v", err)
+	}
+
+	checkWriteProtoset(t, descSrc, exampleProtoset, "TestService")
+	checkWriteProtoset(t, descSrc, testProtoset, "grpc.testing.TestService")
+	checkWriteProtoset(t, descSrc, mergedProtoset, "TestService", "grpc.testing.TestService")
+}
+
+func loadProtoset(path string) (*descriptor.FileDescriptorSet, error) {
+	b, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, err
+	}
+	var protoset descriptor.FileDescriptorSet
+	if err := proto.Unmarshal(b, &protoset); err != nil {
+		return nil, err
+	}
+	return &protoset, nil
+}
+
+func checkWriteProtoset(t *testing.T, descSrc DescriptorSource, protoset *descriptor.FileDescriptorSet, symbols ...string) {
+	var buf bytes.Buffer
+	if err := WriteProtoset(&buf, descSrc, symbols...); err != nil {
+		t.Fatalf("failed to write protoset: %v", err)
+	}
+
+	var result descriptor.FileDescriptorSet
+	if err := proto.Unmarshal(buf.Bytes(), &result); err != nil {
+		t.Fatalf("failed to unmarshal written protoset: %v", err)
+	}
+
+	if !proto.Equal(protoset, &result) {
+		t.Fatalf("written protoset not equal to input:\nExpecting: %s\nActual: %s", protoset, &result)
+	}
+}

go.mod

@@ -2,7 +2,7 @@ module github.com/fullstorydev/grpcurl
 
 require (
 	github.com/golang/protobuf v1.3.1
-	github.com/jhump/protoreflect v1.4.4
+	github.com/jhump/protoreflect v1.5.0
 	golang.org/x/net v0.0.0-20190311183353-d8887717615a
 	google.golang.org/grpc v1.21.0
 )

go.sum

@@ -7,8 +7,8 @@ github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5y
 github.com/golang/protobuf v1.3.1 h1:YF8+flBXS5eO826T4nzqPrxfhQThhXl0YzfuUPu4SBg=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
-github.com/jhump/protoreflect v1.4.4 h1:kySdALZUh7xRtW6UoZjjHtlR8k7rLzx5EXJFRvsO5UY=
-github.com/jhump/protoreflect v1.4.4/go.mod h1:gZ3i/BeD62fjlaIL0VW4UDMT70CTX+3m4pOnAlJ0BX8=
+github.com/jhump/protoreflect v1.5.0 h1:NgpVT+dX71c8hZnxHof2M7QDK7QtohIJ7DYycjnkyfc=
+github.com/jhump/protoreflect v1.5.0/go.mod h1:eaTn3RZAmMBcV0fifFvlm6VHNz3wSkYyXYWUh7ymB74=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/lint v0.0.0-20190313153728-d0100b6bd8b3/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
 golang.org/x/net v0.0.0-20180530234432-1e491301e022/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -21,7 +21,7 @@ golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
-google.golang.org/genproto v0.0.0-20170818100345-ee236bd376b0/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
+google.golang.org/genproto v0.0.0-20170818010345-ee236bd376b0/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8 h1:Nw54tB0rB7hY/N0NQvRW8DG4Yk3Q6T9cu9RcFQDu1tc=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/grpc v1.8.0/go.mod h1:yo6s7OP7yaDglbqo1J04qKzAhqBH6lvTonzMVmEdcZw=

grpcurl.go

@@ -15,6 +15,8 @@ import (
 	"fmt"
 	"io/ioutil"
 	"net"
+	"os"
+	"regexp"
 	"sort"
 	"strings"
 
@@ -161,6 +163,36 @@ func MetadataFromHeaders(headers []string) metadata.MD {
 	return md
 }
 
+var envVarRegex = regexp.MustCompile(`\${\w+}`)
+
+// ExpandHeaders expands environment variables contained in the header string.
+// If no corresponding environment variable is found an error is returned.
+// TODO: Add escaping for `${`
+func ExpandHeaders(headers []string) ([]string, error) {
+	expandedHeaders := make([]string, len(headers))
+	for idx, header := range headers {
+		if header == "" {
+			continue
+		}
+		results := envVarRegex.FindAllString(header, -1)
+		if len(results) == 0 {
+			expandedHeaders[idx] = headers[idx]
+			continue
+		}
+		expandedHeader := header
+		for _, result := range results {
+			envVarName := result[2 : len(result)-1] // strip leading `${` and trailing `}`
+			envVarValue, ok := os.LookupEnv(envVarName)
+			if !ok {
+				return nil, fmt.Errorf("header %q refers to missing environment variable %q", header, envVarName)
+			}
+			expandedHeader = strings.Replace(expandedHeader, result, envVarValue, -1)
+		}
+		expandedHeaders[idx] = expandedHeader
+	}
+	return expandedHeaders, nil
+}
+
 var base64Codecs = []*base64.Encoding{base64.StdEncoding, base64.URLEncoding, base64.RawStdEncoding, base64.RawURLEncoding}
 
 func decode(val string) (string, error) {

grpcurl_test.go

@@ -300,6 +300,33 @@ func TestGetAllFiles(t *testing.T) {
 	}
 }
 
+func TestExpandHeaders(t *testing.T) {
+	inHeaders := []string{"key1: ${value}", "key2: bar", "key3: ${woo", "key4: woo}", "key5: ${TEST}",
+		"key6: ${TEST_VAR}", "${TEST}: ${TEST_VAR}", "key8: ${EMPTY}"}
+	os.Setenv("value", "value")
+	os.Setenv("TEST", "value5")
+	os.Setenv("TEST_VAR", "value6")
+	os.Setenv("EMPTY", "")
+	expectedHeaders := map[string]bool{"key1: value": true, "key2: bar": true, "key3: ${woo": true, "key4: woo}": true,
+		"key5: value5": true, "key6: value6": true, "value5: value6": true, "key8: ": true}
+
+	outHeaders, err := ExpandHeaders(inHeaders)
+	if err != nil {
+		t.Errorf("The ExpandHeaders function generated an unexpected error %s", err)
+	}
+	for _, expandedHeader := range outHeaders {
+		if _, ok := expectedHeaders[expandedHeader]; !ok {
+			t.Errorf("The ExpandHeaders function has returned an unexpected header. Received unexpected header %s", expandedHeader)
+		}
+	}
+
+	badHeaders := []string{"key: ${DNE}"}
+	_, err = ExpandHeaders(badHeaders)
+	if err == nil {
+		t.Errorf("The ExpandHeaders function should return an error for missing environment variables %q", badHeaders)
+	}
+}
+
 func fileNames(files []*desc.FileDescriptor) []string {
 	names := make([]string, len(files))
 	for i, f := range files {