[feature] Basic config validation (#562)

* add optional config validation

* clarify that host and protocol are required

* add validation for host and protocol

* pass prerunArgs as a struct (validate by default)

cmd/gotosocial/admin.go

@@ -46,7 +46,7 @@ func adminCommands() *cobra.Command {
 		Use:   "create",
 		Short: "create a new account",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), account.Create)
@@ -59,7 +59,7 @@ func adminCommands() *cobra.Command {
 		Use:   "confirm",
 		Short: "confirm an existing account manually, thereby skipping email confirmation",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), account.Confirm)
@@ -72,7 +72,7 @@ func adminCommands() *cobra.Command {
 		Use:   "promote",
 		Short: "promote an account to admin",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), account.Promote)
@@ -85,7 +85,7 @@ func adminCommands() *cobra.Command {
 		Use:   "demote",
 		Short: "demote an account from admin to normal user",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), account.Demote)
@@ -98,7 +98,7 @@ func adminCommands() *cobra.Command {
 		Use:   "disable",
 		Short: "prevent an account from signing in or posting etc, but don't delete anything",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), account.Disable)
@@ -111,7 +111,7 @@ func adminCommands() *cobra.Command {
 		Use:   "suspend",
 		Short: "completely remove an account and all of its posts, media, etc",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), account.Suspend)
@@ -124,7 +124,7 @@ func adminCommands() *cobra.Command {
 		Use:   "password",
 		Short: "set a new password for the given account",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), account.Password)
@@ -143,7 +143,7 @@ func adminCommands() *cobra.Command {
 		Use:   "export",
 		Short: "export data from the database to file at the given path",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), trans.Export)
@@ -156,7 +156,7 @@ func adminCommands() *cobra.Command {
 		Use:   "import",
 		Short: "import data from a file into the database",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), trans.Import)

cmd/gotosocial/common.go

@@ -28,15 +28,22 @@
 	"github.com/superseriousbusiness/gotosocial/internal/log"
 )
 
+type preRunArgs struct {
+	cmd            *cobra.Command
+	skipValidation bool
+}
+
 // preRun should be run in the pre-run stage of every cobra command.
 // The goal here is to initialize the viper config store, and also read in
 // the config file (if present).
 //
+// Config then undergoes basic validation if 'skipValidation' is not true.
+//
 // The order of these is important: the init-config function reads the location
 // of the config file from the viper store so that it can be picked up by either
 // env vars or cli flag.
-func preRun(cmd *cobra.Command) error {
-	if err := config.InitViper(cmd.Flags()); err != nil {
+func preRun(a preRunArgs) error {
+	if err := config.InitViper(a.cmd.Flags()); err != nil {
 		return fmt.Errorf("error initializing viper: %s", err)
 	}
 
@@ -44,6 +51,12 @@ func preRun(cmd *cobra.Command) error {
 		return fmt.Errorf("error initializing config: %s", err)
 	}
 
+	if !a.skipValidation {
+		if err := config.Validate(); err != nil {
+			return fmt.Errorf("invalid config: %s", err)
+		}
+	}
+
 	return nil
 }
 

cmd/gotosocial/debug.go

@@ -35,7 +35,7 @@ func debugCommands() *cobra.Command {
 		Use:   "config",
 		Short: "print the collated config (derived from env, flag, and config file) to stdout",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd, skipValidation: true}) // don't do validation for debugging config
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), configaction.Config)

cmd/gotosocial/flag/usage.go

@@ -25,9 +25,9 @@
 	LogDbQueries:               "Log database queries verbosely when log-level is trace or debug",
 	ApplicationName:            "Name of the application, used in various places internally",
 	ConfigPath:                 "Path to a file containing gotosocial configuration. Values set in this file will be overwritten by values set as env vars or arguments",
-	Host:                       "Hostname to use for the server (eg., example.org, gotosocial.whatever.com). DO NOT change this on a server that's already run!",
+	Host:                       "Hostname to use for the server (eg., example.org, gotosocial.whatever.com). This value must be set. DO NOT change this on a server that's already run!",
 	AccountDomain:              "Domain to use in account names (eg., example.org, whatever.com). If not set, will default to the setting for host. DO NOT change this on a server that's already run!",
-	Protocol:                   "Protocol to use for the REST api of the server (only use http for debugging and tests!)",
+	Protocol:                   "Protocol to use for the REST api of the server. This value must be set to one of http or https; only use http for debugging and tests!",
 	BindAddress:                "Bind address to use for the GoToSocial server (eg., 0.0.0.0, 172.138.0.9, [::], localhost). For ipv6, enclose the address in square brackets, eg [2001:db8::fed1]. Default binds to all interfaces.",
 	Port:                       "Port to use for GoToSocial. Change this to 443 if you're running the binary directly on the host machine.",
 	TrustedProxies:             "Proxies to trust when parsing x-forwarded headers into real IPs.",

cmd/gotosocial/server.go

@@ -36,7 +36,7 @@ func serverCommands() *cobra.Command {
 		Use:   "start",
 		Short: "start the gotosocial server",
 		PreRunE: func(cmd *cobra.Command, args []string) error {
-			return preRun(cmd)
+			return preRun(preRunArgs{cmd: cmd})
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return run(cmd.Context(), server.Start)

internal/config/validate.go

@@ -0,0 +1,62 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package config
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/sirupsen/logrus"
+	"github.com/spf13/viper"
+)
+
+// Validate validates global config settings which don't have defaults, to make sure they are set sensibly.
+func Validate() error {
+	errs := []error{}
+
+	// host
+	if viper.GetString(Keys.Host) == "" {
+		errs = append(errs, fmt.Errorf("%s must be set", Keys.Host))
+	}
+
+	// protocol
+	protocol := viper.GetString(Keys.Protocol)
+	switch protocol {
+	case "https":
+		// no problem
+		break
+	case "http":
+		logrus.Warnf("%s was set to 'http'; this should *only* be used for debugging and tests!", Keys.Protocol)
+	case "":
+		errs = append(errs, fmt.Errorf("%s must be set", Keys.Protocol))
+	default:
+		errs = append(errs, fmt.Errorf("%s must be set to either http or https, provided value was %s", Keys.Protocol, protocol))
+	}
+
+	if len(errs) > 0 {
+		errStrings := []string{}
+		for _, err := range errs {
+			errStrings = append(errStrings, err.Error())
+		}
+		return errors.New(strings.Join(errStrings, "; "))
+	}
+
+	return nil
+}

internal/config/validate_test.go

@@ -0,0 +1,90 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package config_test
+
+import (
+	"testing"
+
+	"github.com/spf13/viper"
+	"github.com/stretchr/testify/suite"
+	"github.com/superseriousbusiness/gotosocial/internal/config"
+	"github.com/superseriousbusiness/gotosocial/testrig"
+)
+
+type ConfigValidateTestSuite struct {
+	suite.Suite
+}
+
+func (suite *ConfigValidateTestSuite) TestValidateConfigOK() {
+	testrig.InitTestConfig()
+
+	err := config.Validate()
+	suite.NoError(err)
+}
+
+func (suite *ConfigValidateTestSuite) TestValidateConfigNoHost() {
+	testrig.InitTestConfig()
+
+	viper.Set(config.Keys.Host, "")
+
+	err := config.Validate()
+	suite.EqualError(err, "host must be set")
+}
+
+func (suite *ConfigValidateTestSuite) TestValidateConfigNoProtocol() {
+	testrig.InitTestConfig()
+
+	viper.Set(config.Keys.Protocol, "")
+
+	err := config.Validate()
+	suite.EqualError(err, "protocol must be set")
+}
+
+func (suite *ConfigValidateTestSuite) TestValidateConfigNoProtocolOrHost() {
+	testrig.InitTestConfig()
+
+	viper.Set(config.Keys.Host, "")
+	viper.Set(config.Keys.Protocol, "")
+
+	err := config.Validate()
+	suite.EqualError(err, "host must be set; protocol must be set")
+}
+
+func (suite *ConfigValidateTestSuite) TestValidateConfigBadProtocol() {
+	testrig.InitTestConfig()
+
+	viper.Set(config.Keys.Protocol, "foo")
+
+	err := config.Validate()
+	suite.EqualError(err, "protocol must be set to either http or https, provided value was foo")
+}
+
+func (suite *ConfigValidateTestSuite) TestValidateConfigBadProtocolNoHost() {
+	testrig.InitTestConfig()
+
+	viper.Set(config.Keys.Host, "")
+	viper.Set(config.Keys.Protocol, "foo")
+
+	err := config.Validate()
+	suite.EqualError(err, "host must be set; protocol must be set to either http or https, provided value was foo")
+}
+
+func TestConfigValidateTestSuite(t *testing.T) {
+	suite.Run(t, &ConfigValidateTestSuite{})
+}