Migrate all the api4 to handle errors in idiomatic way (#9143)

api4/scheme.go

@@ -36,14 +36,14 @@ func createScheme(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	var err *model.AppError
-	if scheme, err = c.App.CreateScheme(scheme); err != nil {
+	scheme, err := c.App.CreateScheme(scheme)
+	if err != nil {
 		c.Err = err
 		return
-	} else {
-		w.WriteHeader(http.StatusCreated)
-		w.Write([]byte(scheme.ToJson()))
 	}
+
+	w.WriteHeader(http.StatusCreated)
+	w.Write([]byte(scheme.ToJson()))
 }
 
 func getScheme(c *Context, w http.ResponseWriter, r *http.Request) {
@@ -57,12 +57,13 @@ func getScheme(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if scheme, err := c.App.GetScheme(c.Params.SchemeId); err != nil {
+	scheme, err := c.App.GetScheme(c.Params.SchemeId)
+	if err != nil {
 		c.Err = err
 		return
-	} else {
-		w.Write([]byte(scheme.ToJson()))
 	}
+
+	w.Write([]byte(scheme.ToJson()))
 }
 
 func getSchemes(c *Context, w http.ResponseWriter, r *http.Request) {
@@ -81,12 +82,13 @@ func getSchemes(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if schemes, err := c.App.GetSchemesPage(c.Params.Scope, c.Params.Page, c.Params.PerPage); err != nil {
+	schemes, err := c.App.GetSchemesPage(c.Params.Scope, c.Params.Page, c.Params.PerPage)
+	if err != nil {
 		c.Err = err
 		return
-	} else {
-		w.Write([]byte(model.SchemesToJson(schemes)))
 	}
+
+	w.Write([]byte(model.SchemesToJson(schemes)))
 }
 
 func getTeamsForScheme(c *Context, w http.ResponseWriter, r *http.Request) {
@@ -111,12 +113,13 @@ func getTeamsForScheme(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if teams, err := c.App.GetTeamsForSchemePage(scheme, c.Params.Page, c.Params.PerPage); err != nil {
+	teams, err := c.App.GetTeamsForSchemePage(scheme, c.Params.Page, c.Params.PerPage)
+	if err != nil {
 		c.Err = err
 		return
-	} else {
-		w.Write([]byte(model.TeamListToJson(teams)))
 	}
+
+	w.Write([]byte(model.TeamListToJson(teams)))
 }
 
 func getChannelsForScheme(c *Context, w http.ResponseWriter, r *http.Request) {
@@ -141,12 +144,13 @@ func getChannelsForScheme(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if channels, err := c.App.GetChannelsForSchemePage(scheme, c.Params.Page, c.Params.PerPage); err != nil {
+	channels, err := c.App.GetChannelsForSchemePage(scheme, c.Params.Page, c.Params.PerPage)
+	if err != nil {
 		c.Err = err
 		return
-	} else {
-		w.Write([]byte(channels.ToJson()))
 	}
+
+	w.Write([]byte(channels.ToJson()))
 }
 
 func patchScheme(c *Context, w http.ResponseWriter, r *http.Request) {
@@ -177,13 +181,14 @@ func patchScheme(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if scheme, err = c.App.PatchScheme(scheme, patch); err != nil {
+	scheme, err = c.App.PatchScheme(scheme, patch)
+	if err != nil {
 		c.Err = err
 		return
-	} else {
-		c.LogAudit("")
-		w.Write([]byte(scheme.ToJson()))
 	}
+
+	c.LogAudit("")
+	w.Write([]byte(scheme.ToJson()))
 }
 
 func deleteScheme(c *Context, w http.ResponseWriter, r *http.Request) {