6 files changed, 33 insertions, 18 deletions

diff --git a/cmd/mattermost/commands/server.go b/cmd/mattermost/commands/server.go
index 9d0e5a917..299005b6a 100644
--- a/cmd/mattermost/commands/server.go
+++ b/cmd/mattermost/commands/server.go
@@ -6,6 +6,8 @@ package commands
 import (
 	"fmt"
 	"net"
+	"net/http"
+	"net/url"
 	"os"
 	"os/signal"
 	"syscall"
@@ -129,7 +131,19 @@ func runServer(configFileLocation string, disableConfigWatch bool, usedPlatform
 
 	// Enable developer settings if this is a "dev" build
 	if model.BuildNumber == "dev" {
-		a.UpdateConfig(func(cfg *model.Config) { *cfg.ServiceSettings.EnableDeveloper = true })
+		a.UpdateConfig(func(cfg *model.Config) {
+			*cfg.ServiceSettings.EnableDeveloper = true
+			if *cfg.ServiceSettings.SiteURL == "" {
+				*cfg.ServiceSettings.SiteURL = "http://localhost:8065"
+			}
+		})
+	}
+
+	// SiteURL should be set at this point. Either by a user or by the dev mode above
+	// This is here instead of in config.IsValid because there are many tests that make the assumption
+	// that the default config is valid. Which it is not.
+	if _, err := url.ParseRequestURI(*a.Config().ServiceSettings.SiteURL); err != nil {
+		return model.NewAppError("Config.IsValid", "model.config.is_valid.site_url.app_error", nil, "", http.StatusBadRequest)
 	}
 
 	resetStatuses(a)
diff --git a/cmd/mattermost/commands/server_test.go b/cmd/mattermost/commands/server_test.go
index 0f825e316..a0c7c6948 100644
--- a/cmd/mattermost/commands/server_test.go
+++ b/cmd/mattermost/commands/server_test.go
@@ -11,6 +11,7 @@ import (
 	"testing"
 
 	"github.com/mattermost/mattermost-server/jobs"
+	"github.com/mattermost/mattermost-server/model"
 	"github.com/mattermost/mattermost-server/utils"
 	"github.com/stretchr/testify/require"
 )
@@ -20,6 +21,7 @@ type ServerTestHelper struct {
 	disableConfigWatch bool
 	interruptChan      chan os.Signal
 	originalInterval   int
+	oldBuildNumber     string
 }
 
 func SetupServerTest() *ServerTestHelper {
@@ -41,14 +43,20 @@ func SetupServerTest() *ServerTestHelper {
 		interruptChan:      interruptChan,
 		originalInterval:   originalInterval,
 	}
+
+	// Run in dev mode so SiteURL gets set
+	th.oldBuildNumber = model.BuildNumber
+	model.BuildNumber = "dev"
+
 	return th
 }
 
 func (th *ServerTestHelper) TearDownServerTest() {
 	jobs.DEFAULT_WATCHER_POLLING_INTERVAL = th.originalInterval
+	model.BuildNumber = th.oldBuildNumber
 }
 
-func TestRunServerSuccess(t *testing.T) {
+func TestRunServerSiteURL(t *testing.T) {
 	th := SetupServerTest()
 	defer th.TearDownServerTest()
 
diff --git a/config/default.json b/config/default.json
index 23bae64f9..97b2696aa 100644
--- a/config/default.json
+++ b/config/default.json
@@ -1,6 +1,6 @@
 {
     "ServiceSettings": {
-        "SiteURL": "http://localhost:8065",
+        "SiteURL": "",
         "WebsocketURL": "",
         "LicenseFileLocation": "",
         "ListenAddress": ":8065",
diff --git a/i18n/en.json b/i18n/en.json
index f7c21a3eb..47bb743bb 100644
--- a/i18n/en.json
+++ b/i18n/en.json
@@ -5228,7 +5228,7 @@
   },
   {
     "id": "model.config.is_valid.site_url.app_error",
-    "translation": "Site URL must be a valid URL and start with http:// or https://"
+    "translation": "Site URL must be set, a valid URL, and start with http:// or https://"
   },
   {
     "id": "model.config.is_valid.site_url_email_batching.app_error",
diff --git a/model/config.go b/model/config.go
index a54d44110..4710658ec 100644
--- a/model/config.go
+++ b/model/config.go
@@ -1870,18 +1870,10 @@ func (o *Config) SetDefaults() {
 }
 
 func (o *Config) IsValid() *AppError {
-	if len(*o.ServiceSettings.SiteURL) == 0 && *o.EmailSettings.EnableEmailBatching {
-		return NewAppError("Config.IsValid", "model.config.is_valid.site_url_email_batching.app_error", nil, "", http.StatusBadRequest)
-	}
-
 	if *o.ClusterSettings.Enable && *o.EmailSettings.EnableEmailBatching {
 		return NewAppError("Config.IsValid", "model.config.is_valid.cluster_email_batching.app_error", nil, "", http.StatusBadRequest)
 	}
 
-	if len(*o.ServiceSettings.SiteURL) == 0 && *o.ServiceSettings.AllowCookiesForSubdomains {
-		return NewAppError("Config.IsValid", "Allowing cookies for subdomains requires SiteURL to be set.", nil, "", http.StatusBadRequest)
-	}
-
 	if err := o.TeamSettings.isValid(); err != nil {
 		return err
 	}
@@ -2187,12 +2179,6 @@ func (ss *ServiceSettings) isValid() *AppError {
 		return NewAppError("Config.IsValid", "model.config.is_valid.login_attempts.app_error", nil, "", http.StatusBadRequest)
 	}
 
-	if len(*ss.SiteURL) != 0 {
-		if _, err := url.ParseRequestURI(*ss.SiteURL); err != nil {
-			return NewAppError("Config.IsValid", "model.config.is_valid.site_url.app_error", nil, "", http.StatusBadRequest)
-		}
-	}
-
 	if len(*ss.WebsocketURL) != 0 {
 		if _, err := url.ParseRequestURI(*ss.WebsocketURL); err != nil {
 			return NewAppError("Config.IsValid", "model.config.is_valid.websocket_url.app_error", nil, "", http.StatusBadRequest)
diff --git a/model/config_test.go b/model/config_test.go
index b7533145b..e39ecef3b 100644
--- a/model/config_test.go
+++ b/model/config_test.go
@@ -82,6 +82,13 @@ func TestConfigDefaultFileSettingsS3SSE(t *testing.T) {
 	}
 }
 
+func TestConfigDefaultSiteURL(t *testing.T) {
+	c1 := Config{}
+	c1.SetDefaults()
+
+	assert.Equal(t, "", *c1.ServiceSettings.SiteURL, "SiteURL should be empty by default.")
+}
+
 func TestConfigDefaultServiceSettingsExperimentalGroupUnreadChannels(t *testing.T) {
 	c1 := Config{}
 	c1.SetDefaults()