Use mutex for file operations

config.go

@@ -6,6 +6,7 @@ import (
 	"log"
 	"os"
 	"strings"
+	"sync"
 )
 
 var (
@@ -152,6 +153,7 @@ func initConfig() (err error) {
 				password: cfg.Git.Password,
 				name:     cfg.Git.AuthorName,
 				email:    cfg.Git.AuthorEmail,
+				lock:     &sync.Mutex{},
 			}
 		}
 		return nil

go.mod

@@ -10,8 +10,9 @@ require (
 	github.com/google/go-cmp v0.4.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/stretchr/testify v1.5.1 // indirect
-	golang.org/x/crypto v0.0.0-20200323165209-0ec3e9974c59 // indirect
+	golang.org/x/crypto v0.0.0-20200420104511-884d27f42877 // indirect
 	golang.org/x/net v0.0.0-20200324143707-d3edc9973b7e // indirect
+	golang.org/x/sys v0.0.0-20200420163511-1957bb5e6d1f // indirect
 	gopkg.in/yaml.v2 v2.2.8
 	willnorris.com/go/webmention v0.0.0-20200126231626-5a55fff6bf71
 )

go.sum

@@ -70,6 +70,8 @@ golang.org/x/crypto v0.0.0-20200302210943-78000ba7a073 h1:xMPOj6Pz6UipU1wXLkrtqp
 golang.org/x/crypto v0.0.0-20200302210943-78000ba7a073/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20200323165209-0ec3e9974c59 h1:3zb4D3T4G8jdExgVU/95+vQXfpEPiMdCaZgmGVxjNHM=
 golang.org/x/crypto v0.0.0-20200323165209-0ec3e9974c59/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20200420104511-884d27f42877 h1:IhZPbxNd1UjBCaD5AfpSSbJTRlp+ZSuyuH5uoksNS04=
+golang.org/x/crypto v0.0.0-20200420104511-884d27f42877/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/net v0.0.0-20180218175443-cbe0f9307d01/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180911220305-26e67e76b6c3/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
@@ -84,6 +86,8 @@ golang.org/x/sys v0.0.0-20200302150141-5c8b2ff67527 h1:uYVVQ9WP/Ds2ROhcaGPeIdVq0
 golang.org/x/sys v0.0.0-20200302150141-5c8b2ff67527/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd h1:xhmwyvizuTgC2qz7ZlMluP20uW+C3Rm0FD/WLDX8884=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200420163511-1957bb5e6d1f h1:gWF768j/LaZugp8dyS4UwsslYCYz9XgFxvlgsn0n9H8=
+golang.org/x/sys v0.0.0-20200420163511-1957bb5e6d1f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=

storage.go

@@ -8,6 +8,7 @@ import (
 	"io/ioutil"
 	"os"
 	"path"
+	"sync"
 	"time"
 )
 
@@ -24,9 +25,10 @@ type Git struct {
 	password string
 	name     string
 	email    string
+	lock     *sync.Mutex
 }
 
-func (g Git) init() (r *git.Repository, w *git.Worktree, err error) {
+func (g *Git) init() (r *git.Repository, w *git.Worktree, err error) {
 	// Open repo
 	r, err = git.PlainOpen(g.filepath)
 	if err == nil {
@@ -72,11 +74,11 @@ func (g Git) init() (r *git.Repository, w *git.Worktree, err error) {
 	return
 }
 
-func (g Git) destroyRepo() {
+func (g *Git) destroyRepo() {
 	_ = os.RemoveAll(g.filepath)
 }
 
-func (g Git) push(repository *git.Repository) error {
+func (g *Git) push(repository *git.Repository) error {
 	err := repository.Push(&git.PushOptions{
 		Auth: &gitHttp.BasicAuth{
 			Username: g.username,
@@ -92,7 +94,9 @@ func (g Git) push(repository *git.Repository) error {
 	}
 }
 
-func (g Git) CreateFile(filepath string, file string, message string) (err error) {
+func (g *Git) CreateFile(filepath string, file string, message string) (err error) {
+	g.lock.Lock()
+	defer g.lock.Unlock()
 	_, _, err = g.init()
 	if err != nil {
 		err = errors.New("failed to initialize repo")
@@ -102,11 +106,17 @@ func (g Git) CreateFile(filepath string, file string, message string) (err error
 	if _, e := os.Stat(joinedPath); e == nil {
 		return errors.New("file already exists")
 	} else {
-		return g.UpdateFile(filepath, file, message)
+		return g.unsafeUpdateFile(filepath, file, message)
 	}
 }
 
-func (g Git) UpdateFile(filepath string, file string, message string) error {
+func (g *Git) UpdateFile(filepath string, file string, message string) error {
+	g.lock.Lock()
+	defer g.lock.Unlock()
+	return g.unsafeUpdateFile(filepath, file, message)
+}
+
+func (g *Git) unsafeUpdateFile(filepath string, file string, message string) error {
 	repo, w, err := g.init()
 	if err != nil {
 		return errors.New("failed to initialize repo")
@@ -137,7 +147,9 @@ func (g Git) UpdateFile(filepath string, file string, message string) error {
 	return g.push(repo)
 }
 
-func (g Git) DeleteFile(filepath string, message string) (err error) {
+func (g *Git) DeleteFile(filepath string, message string) (err error) {
+	g.lock.Lock()
+	defer g.lock.Unlock()
 	repo, w, err := g.init()
 	if err != nil {
 		return errors.New("failed to initialize repo")