Code cleanup from PR 255 feedback. T705

database.go

@@ -12,11 +12,8 @@ package writefreely
 
 import (
 	"context"
-	"crypto/rand"
 	"database/sql"
 	"fmt"
-	"github.com/pkg/errors"
-	"math/big"
 	"net/http"
 	"strings"
 	"time"
@@ -2463,11 +2460,8 @@ func (db *datastore) GetCollectionLastPostTime(id int64) (*time.Time, error) {
 }
 
 func (db *datastore) GenerateOAuthState(ctx context.Context) (string, error) {
-	state, err := randString(24)
-	if err != nil {
-		return "", err
-	}
-	_, err = db.ExecContext(ctx, "INSERT INTO oauth_client_state (state, used, created_at) VALUES (?, FALSE, NOW())", state)
+	state := store.Generate62RandomString(24)
+	_, err := db.ExecContext(ctx, "INSERT INTO oauth_client_state (state, used, created_at) VALUES (?, FALSE, NOW())", state)
 	if err != nil {
 		return "", fmt.Errorf("unable to record oauth client state: %w", err)
 	}
@@ -2545,26 +2539,3 @@ func handleFailedPostInsert(err error) error {
 	log.Error("Couldn't insert into posts: %v", err)
 	return err
 }
-
-func randString(length int) (string, error) {
-	// every printable character on a US keyboard
-	charset := []rune("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789")
-	out := make([]rune, length)
-
-	setLen := big.NewInt(int64(len(charset)))
-	for idx := 0; idx < length; idx++ {
-		offset, err := rand.Int(rand.Reader, setLen)
-		if err != nil {
-			return "", err
-		}
-
-		if !offset.IsUint64() {
-			// this should (in theory) never happen
-			return "", errors.Errorf("Non-Uint64 offset returned from rand.Int")
-		}
-
-		out[idx] = charset[offset.Uint64()]
-	}
-
-	return string(out), nil
-}

oauth.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"github.com/gorilla/sessions"
 	"github.com/guregu/null/zero"
+	"github.com/writeas/nerds/store"
 	"github.com/writeas/web-core/auth"
 	"github.com/writeas/web-core/log"
 	"github.com/writeas/writefreely/config"
@@ -143,11 +144,7 @@ func (h oauthHandler) viewOauthCallback(w http.ResponseWriter, r *http.Request)
 		//create a random string. If the user needs to set a password, they
 		//can do so through the settings page or through the password reset
 		//flow.
-		randPass, err := randString(14)
-		if err != nil {
-			failOAuthRequest(w, http.StatusInternalServerError, err.Error())
-			return
-		}
+		randPass := store.Generate62RandomString(14)
 		hashedPass, err := auth.HashPass([]byte(randPass))
 		if err != nil {
 			log.ErrorLog.Println(err)

oauth_test.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"github.com/gorilla/sessions"
 	"github.com/stretchr/testify/assert"
+	"github.com/writeas/nerds/store"
 	"github.com/writeas/writefreely/config"
 	"net/http"
 	"net/http/httptest"
@@ -120,7 +121,7 @@ func (m *MockOAuthDatastore) GenerateOAuthState(ctx context.Context) (string, er
 	if m.DoGenerateOAuthState != nil {
 		return m.DoGenerateOAuthState(ctx)
 	}
-	return randString(14)
+	return store.Generate62RandomString(14), nil
 }
 
 func TestViewOauthInit(t *testing.T) {