Support building without SQLite support

This adds a new `sqlite` build tag that you should include only if you
want SQLite3 support built in. Both `make run` and `make release` create
builds with SQLite included.

Makefile

@@ -13,25 +13,25 @@ IMAGE_NAME=writeas/writefreely
 all : build
 
 build: assets deps
-	cd cmd/writefreely; $(GOBUILD) -v
+	cd cmd/writefreely; $(GOBUILD) -v -tags='sqlite'
 
 build-linux: deps
 	@hash xgo > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
 		$(GOGET) -u github.com/karalabe/xgo; \
 	fi
-	xgo --targets=linux/amd64, -dest build/ $(LDFLAGS) -out writefreely ./cmd/writefreely
+	xgo --targets=linux/amd64, -dest build/ $(LDFLAGS) -tags='sqlite' -out writefreely ./cmd/writefreely
 
 build-windows: deps
 	@hash xgo > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
 		$(GOGET) -u github.com/karalabe/xgo; \
 	fi
-	xgo --targets=windows/amd64, -dest build/ $(LDFLAGS) -out writefreely ./cmd/writefreely
+	xgo --targets=windows/amd64, -dest build/ $(LDFLAGS) -tags='sqlite' -out writefreely ./cmd/writefreely
 
 build-darwin: deps
 	@hash xgo > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
 		$(GOGET) -u github.com/karalabe/xgo; \
 	fi
-	xgo --targets=darwin/amd64, -dest build/ $(LDFLAGS) -out writefreely ./cmd/writefreely
+	xgo --targets=darwin/amd64, -dest build/ $(LDFLAGS) -tags='sqlite' -out writefreely ./cmd/writefreely
 
 build-docker :
 	$(DOCKERCMD) build -t $(IMAGE_NAME):latest -t $(IMAGE_NAME):$(GITREV) .
@@ -40,7 +40,7 @@ test:
 	$(GOTEST) -v ./...
 
 run: dev-assets
-	$(GOINSTALL) ./...
+	$(GOINSTALL) -tags='sqlite' ./...
 	$(BINARY_NAME) --debug
 
 deps :

app.go

@@ -25,7 +25,6 @@ import (
 	"time"
 
 	_ "github.com/go-sql-driver/mysql"
-	_ "github.com/mattn/go-sqlite3"
 
 	"github.com/gorilla/mux"
 	"github.com/gorilla/schema"
@@ -476,6 +475,10 @@ func connectToDatabase(app *app) {
 		db, err = sql.Open(app.cfg.Database.Type, fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?charset=utf8mb4&parseTime=true&loc=%s", app.cfg.Database.User, app.cfg.Database.Password, app.cfg.Database.Host, app.cfg.Database.Port, app.cfg.Database.Database, url.QueryEscape(time.Local.String())))
 		db.SetMaxOpenConns(50)
 	} else if app.cfg.Database.Type == "sqlite3" {
+		if !SQLiteEnabled {
+			log.Error("Invalid database type '%s'. Binary wasn't compiled with SQLite3 support.", app.cfg.Database.Type)
+			os.Exit(1)
+		}
 		if app.cfg.Database.FileName == "" {
 			log.Error("SQLite database filename value in config.ini is empty.")
 			os.Exit(1)

database-no-sqlite.go

@@ -0,0 +1,30 @@
+// +build !sqlite
+
+/*
+ * Copyright © 2019 A Bunch Tell LLC.
+ *
+ * This file is part of WriteFreely.
+ *
+ * WriteFreely is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, included
+ * in the LICENSE file in this source code package.
+ */
+
+package writefreely
+
+import (
+	"github.com/go-sql-driver/mysql"
+	"github.com/writeas/web-core/log"
+)
+
+func (db *datastore) isDuplicateKeyErr(err error) bool {
+	if db.driverName == driverMySQL {
+		if mysqlErr, ok := err.(*mysql.MySQLError); ok {
+			return mysqlErr.Number == mySQLErrDuplicateKey
+		}
+	} else {
+		log.Error("isDuplicateKeyErr: failed check for unrecognized driver '%s'", db.driverName)
+	}
+
+	return false
+}

database-sqlite.go

@@ -0,0 +1,39 @@
+// +build sqlite
+
+/*
+ * Copyright © 2019 A Bunch Tell LLC.
+ *
+ * This file is part of WriteFreely.
+ *
+ * WriteFreely is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, included
+ * in the LICENSE file in this source code package.
+ */
+
+package writefreely
+
+import (
+	"github.com/go-sql-driver/mysql"
+	"github.com/mattn/go-sqlite3"
+	"github.com/writeas/web-core/log"
+)
+
+func init() {
+	SQLiteEnabled = true
+}
+
+func (db *datastore) isDuplicateKeyErr(err error) bool {
+	if db.driverName == driverSQLite {
+		if err, ok := err.(sqlite3.Error); ok {
+			return err.Code == sqlite3.ErrConstraint
+		}
+	} else if db.driverName == driverMySQL {
+		if mysqlErr, ok := err.(*mysql.MySQLError); ok {
+			return mysqlErr.Number == mySQLErrDuplicateKey
+		}
+	} else {
+		log.Error("isDuplicateKeyErr: failed check for unrecognized driver '%s'", db.driverName)
+	}
+
+	return false
+}

database.go

@@ -17,9 +17,6 @@ import (
 	"strings"
 	"time"
 
-	"github.com/go-sql-driver/mysql"
-	"github.com/mattn/go-sqlite3"
-
 	"github.com/guregu/null"
 	"github.com/guregu/null/zero"
 	uuid "github.com/nu7hatch/gouuid"
@@ -41,6 +38,10 @@ const (
 	driverSQLite = "sqlite3"
 )
 
+var (
+	SQLiteEnabled bool
+)
+
 type writestore interface {
 	CreateUser(*User, string) error
 	UpdateUserEmail(keys *keychain, userID int64, email string) error
@@ -149,22 +150,6 @@ func (db *datastore) dateSub(l int, unit string) string {
 	return fmt.Sprintf("DATE_SUB(NOW(), INTERVAL %d %s)", l, unit)
 }
 
-func (db *datastore) isDuplicateKeyErr(err error) bool {
-	if db.driverName == driverSQLite {
-		if err, ok := err.(sqlite3.Error); ok {
-			return err.Code == sqlite3.ErrConstraint
-		}
-	} else if db.driverName == driverMySQL {
-		if mysqlErr, ok := err.(*mysql.MySQLError); ok {
-			return mysqlErr.Number == mySQLErrDuplicateKey
-		}
-	} else {
-		log.Error("isDuplicateKeyErr: failed check for unrecognized driver '%s'", db.driverName)
-	}
-
-	return false
-}
-
 func (db *datastore) CreateUser(u *User, collectionTitle string) error {
 	// New users get a `users` and `collections` row.
 	t, err := db.Begin()