Allow printing SCIP index as JSON

cmd/convert.go

@@ -29,7 +29,7 @@ func convertCommand() cli.Command {
 				Name:        "to",
 				Usage:       "Output path for LSIF index",
 				Destination: &convertFlags.to,
-				Value: "dump.lsif",
+				Value:       "dump.lsif",
 			},
 		},
 		Action: func(c *cli.Context) error {

cmd/json.go

@@ -0,0 +1,56 @@
+package main
+
+import (
+	"io"
+
+	"github.com/sourcegraph/sourcegraph/lib/errors"
+	"github.com/urfave/cli/v2"
+	"google.golang.org/protobuf/encoding/protojson"
+)
+
+type jsonFlags struct {
+	from   string
+	pretty bool
+}
+
+func jsonCommand() cli.Command {
+	var jsonFlags jsonFlags
+
+	json := cli.Command{
+		Name:  "json",
+		Usage: "Print SCIP index as JSON",
+		Flags: []cli.Flag{
+			fromFlag(&jsonFlags.from),
+			&cli.BoolFlag{
+				Name:        "pretty",
+				Usage:       "Pretty print (multiline, with indentation)",
+				Aliases:     []string{"p"},
+				Destination: &jsonFlags.pretty,
+			},
+		},
+		Action: func(c *cli.Context) error {
+			if jsonFlags.from == "" {
+				return errors.New("missing argument for path to SCIP index")
+			}
+			return jsonMain(jsonFlags, c.App.Writer)
+		},
+	}
+
+	return json
+}
+
+func jsonMain(flags jsonFlags, out io.Writer) error {
+	scipIndex, err := readFromOption(flags.from)
+	if err != nil {
+		return err
+	}
+
+	options := protojson.MarshalOptions{
+		Multiline: flags.pretty,
+	}
+
+	jsonBytes, _ := options.Marshal(scipIndex)
+	out.Write(jsonBytes)
+
+	return nil
+}

cmd/json_test.go

@@ -0,0 +1,69 @@
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+	"io/ioutil"
+	"log"
+	"os"
+	"testing"
+
+	"github.com/sourcegraph/scip/bindings/go/scip"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/protobuf/proto"
+)
+
+func TestJSONCommand(t *testing.T) {
+	app := scipApp()
+	// Redirect CLI writer to a buffer
+	var buff bytes.Buffer
+	app.Writer = io.Writer(&buff)
+	idx := makeIndex([]string{"a"}, stringMap{"f": {"b"}}, stringMap{"f": {"a", "b"}})
+
+	idx.Metadata = &scip.Metadata{ProjectRoot: "howdy"}
+
+	// Serialise SCIP index
+	indexBytes, err := proto.Marshal(idx)
+
+	// Write SCIP index to a temp file
+	dir := os.TempDir()
+	file, err := ioutil.TempFile(dir, "scip-cli-json-test*.scip")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer os.Remove(file.Name())
+
+	_, fErr := file.Write(indexBytes)
+	if fErr != nil {
+		log.Fatal(fErr)
+	}
+
+	// Run the JSON command with the temporary file
+	runErr := app.Run([]string{"scip", "json", "--from", file.Name()})
+	if runErr != nil {
+		log.Fatal(runErr)
+	}
+
+	type JsonIndex struct {
+		Metadata struct {
+			ProjectRoot string `json:"projectRoot"`
+		}
+		Documents []struct {
+			RelativePath string `json:"relativePath"`
+		} `json:"documents"`
+	}
+
+	var roundtripResult JsonIndex
+
+	bytes := buff.Bytes()
+
+	jsonErr := json.Unmarshal(bytes, &roundtripResult)
+	if jsonErr != nil {
+		log.Fatal(jsonErr)
+	}
+
+	require.Equal(t, roundtripResult.Metadata.ProjectRoot, "howdy")
+	require.Equal(t, len(roundtripResult.Documents), 1)
+	require.Equal(t, roundtripResult.Documents[0].RelativePath, "f")
+}

cmd/main.go

@@ -24,7 +24,8 @@ func commands() []*cli.Command {
 	print := printCommand()
 	snapshot := snapshotCommand()
 	stats := statsCommand()
-	return []*cli.Command{&convert, &lint, &print, &snapshot, &stats}
+	json := jsonCommand()
+	return []*cli.Command{&convert, &lint, &print, &snapshot, &stats, &json}
 }
 
 //go:embed version.txt

docs/CLI.md

@@ -1,5 +1,16 @@
 # SCIP CLI Reference
 
+<!--toc:start-->
+
+- [SCIP CLI Reference](#scip-cli-reference)
+  - [`scip convert`](#scip-convert)
+  - [`scip lint`](#scip-lint)
+  - [`scip print`](#scip-print)
+  - [`scip snapshot`](#scip-snapshot)
+  - [`scip stats`](#scip-stats)
+  - [`scip json`](#scip-json)
+  <!--toc:end-->
+
 ```
 NAME:
    scip - SCIP Code Intelligence Protocol CLI
@@ -21,6 +32,7 @@ COMMANDS:
    print     Print a SCIP index in a human-readable format for debugging
    snapshot  Generate snapshot files for golden testing
    stats     Output useful statistics about a SCIP index
+   json      Print SCIP index as JSON
    help, h   Shows a list of commands or help for one command
 
 GLOBAL OPTIONS:
@@ -96,8 +108,12 @@ DESCRIPTION:
    and symbol information.
 
 OPTIONS:
-   --from value  Path to SCIP index file (default: index.scip)
-   --to value    Path to output directory for snapshot files (default: scip-snapshot)
+   --comment-syntax value  Comment syntax to use for snapshot files (default: "//")
+   --from value            Path to SCIP index file (default: "index.scip")
+   --help, -h              show help (default: false)
+   --project-root value    Override project root in the SCIP file. For example, this can be helpful when the SCIP index was created inside a Docker image or created on another computer
+   --strict                If true, fail fast on errors (default: true)
+   --to value              Path to output directory for snapshot files (default: "scip-snapshot")
 ```
 
 ## `scip stats`
@@ -112,3 +128,18 @@ USAGE:
 OPTIONS:
    --from value  Path to SCIP index file (default: index.scip)
 ```
+
+## `scip json`
+
+```
+NAME:
+   scip json - Print SCIP index as JSON
+
+USAGE:
+   scip json [command options] [arguments...]
+
+OPTIONS:
+   --from value  Path to SCIP index file (default: "index.scip")
+   --help, -h    show help (default: false)
+   --pretty, -p  Pretty print (multiline, with indentation) (default: false)
+```