Add moniker support (#23)

Add support for monikers using go.mod and go.sum files.

.gitignore

@@ -15,4 +15,5 @@
 /.vscode
 /.idea
 /lsif-go
+/lsif-gomod
 /data.lsif

README.md

@@ -10,20 +10,20 @@ A first draft specification can be found [here](https://github.com/Microsoft/lan
 
 ## Quickstart
 
-1. Download and build this program via `go get github.com/sourcegraph/lsif-go`.
+1. Download and build this program via `go get github.com/sourcegraph/lsif-go/cmd/lsif-go`.
 2. The binary `lsif-go` should be installed into your `$GOPATH/bin` directory.
 3. Make sure you have added `$GOPATH/bin` to your `$PATH` envrionment variable.
-4. Go to a root directory of a Go project, then execute `lsif-go export`:
+4. Go to a root directory of a Go project, then execute `lsif-go`:
 
 ```
-➜ lsif-go export
+➜ lsif-go --out data.lsif
 4 package(s), 10 file(s), 597 def(s), 11521 element(s)
 Processed in 770.817859ms
 ```
 
-By default, the exporter dumps LSIF data to the file `data.lsif` in the working directory.
+By default, the indexer will read the current directory as the root of the project.
 
-Use `lsif-go -h` for more information
+Use `lsif-go --help` for more information
 
 ## Try it out!
 

cmd/lsif-go/main.go

@@ -0,0 +1,100 @@
+// The program lsif-go is an LSIF exporter for Go.
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"time"
+
+	"github.com/alecthomas/kingpin"
+	"github.com/sourcegraph/lsif-go/export"
+	"github.com/sourcegraph/lsif-go/log"
+	"github.com/sourcegraph/lsif-go/protocol"
+)
+
+const version = "0.4.1"
+const versionString = version + ", protocol version " + protocol.Version
+
+func main() {
+	if err := realMain(); err != nil {
+		fmt.Fprint(os.Stderr, fmt.Sprintf("error: %v\n", err))
+		os.Exit(1)
+	}
+}
+
+func realMain() error {
+	var (
+		debug       bool
+		verbose     bool
+		projectRoot string
+		noContents  bool
+		outFile     string
+		stdout      bool
+	)
+
+	app := kingpin.New("lsif-go", "lsif-go is an LSIF exporter for Go.").Version(versionString)
+	app.Flag("debug", "Display debug information.").Default("false").BoolVar(&debug)
+	app.Flag("verbose", "Display verbose information.").Short('v').Default("false").BoolVar(&verbose)
+	app.Flag("projectRoot", "Specifies the project root. Defaults to the current working directory.").Default(".").StringVar(&projectRoot)
+	app.Flag("noContents", "File contents will not be embedded into the dump.").Default("false").BoolVar(&noContents)
+	app.Flag("out", "The output file the dump is save to.").StringVar(&outFile)
+	app.Flag("stdout", "Writes the dump to stdout.").Default("false").BoolVar(&stdout)
+
+	_, err := app.Parse(os.Args[1:])
+	if err != nil {
+		return err
+	}
+
+	if outFile == "" && !stdout {
+		return fmt.Errorf("either an output file using --out or --stdout must be specified")
+	}
+
+	if debug {
+		log.SetLevel(log.Debug)
+	}
+
+	if verbose {
+		log.SetLevel(log.Info)
+	}
+
+	if stdout && (verbose || debug) {
+		return fmt.Errorf("debug and verbose options cannot be enabled with --stdout")
+	}
+
+	start := time.Now()
+
+	var out io.Writer
+	if stdout {
+		out = os.Stdout
+	} else {
+		file, err := os.Create(outFile)
+		if err != nil {
+			return fmt.Errorf("create dump file: %v", err)
+		}
+
+		defer file.Close()
+		out = file
+	}
+
+	s, err := export.Export(
+		projectRoot,
+		noContents,
+		out,
+		protocol.ToolInfo{
+			Name:    "lsif-go",
+			Version: version,
+			Args:    os.Args[1:],
+		},
+	)
+	if err != nil {
+		return fmt.Errorf("export: %v", err)
+	}
+
+	if !stdout {
+		log.Printf("%d package(s), %d file(s), %d def(s), %d element(s)", s.NumPkgs, s.NumFiles, s.NumDefs, s.NumElements)
+		log.Println("Processed in", time.Since(start))
+	}
+
+	return nil
+}

cmd/lsif-gomod/main.go

@@ -0,0 +1,80 @@
+// The program lsif-gomod adds gomod moniker support to lsif-go output.
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/alecthomas/kingpin"
+	"github.com/sourcegraph/lsif-go/gomod"
+	"github.com/sourcegraph/lsif-go/protocol"
+)
+
+const version = "0.4.1"
+const versionString = version + ", protocol version " + protocol.Version
+
+func main() {
+	if err := realMain(); err != nil {
+		fmt.Fprint(os.Stderr, fmt.Sprintf("error: %v\n", err))
+		os.Exit(1)
+	}
+}
+
+func realMain() error {
+	var (
+		projectRoot string
+		inFile      string
+		stdin       bool
+		outFile     string
+		stdout      bool
+	)
+
+	app := kingpin.New("lsif-gomod", "lsif-gomod decorates lsif-go output with gomod monikers.").Version(versionString)
+	app.Flag("projectRoot", "Specifies the project root. Defaults to the current working directory.").Default(".").StringVar(&projectRoot)
+	app.Flag("in", "Specifies the file that contains a LSIF dump.").StringVar(&inFile)
+	app.Flag("stdin", "Reads the dump from stdin.").Default("false").BoolVar(&stdin)
+	app.Flag("out", "The output file the converted dump is saved to.").StringVar(&outFile)
+	app.Flag("stdout", "Writes the dump to stdout.").Default("false").BoolVar(&stdout)
+
+	_, err := app.Parse(os.Args[1:])
+	if err != nil {
+		return err
+	}
+
+	if inFile == "" && !stdin {
+		return fmt.Errorf("either an input file using --in or --stdin must be specified")
+	}
+
+	if outFile == "" && !stdout {
+		return fmt.Errorf("either an output file using --out or --stdout must be specified")
+	}
+
+	var in io.Reader
+	if stdin {
+		in = os.Stdin
+	} else {
+		file, err := os.Open(inFile)
+		if err != nil {
+			return fmt.Errorf("open dump file: %v", err)
+		}
+
+		defer file.Close()
+		in = file
+	}
+
+	var out io.Writer
+	if stdout {
+		out = os.Stdout
+	} else {
+		file, err := os.Create(outFile)
+		if err != nil {
+			return fmt.Errorf("create dump file: %v", err)
+		}
+
+		defer file.Close()
+		out = file
+	}
+
+	return gomod.Decorate(in, out, projectRoot)
+}