Performance improvements for 40M posts (#7708)

* Optimizing get root posts SQL query

* Setting session invalidation to be reliable

* Adding app reciever to SessionHasPermissionToUser

* Adding app reciever to SessionHasPermissionToTeam

* Adding app reciever to SessionHasPermissionTo

* Clear session cache if permission was denied

* Fixing rebase issues

* Revert "Optimizing get root posts SQL query"

This reverts commit f364757e7015cfb4ec673d0a4fc3d57cd25d8dd7.

* Fixing build

api4/plugin.go

@@ -9,7 +9,6 @@ import (
 	"net/http"
 
 	l4g "github.com/alecthomas/log4go"
-	"github.com/mattermost/mattermost-server/app"
 	"github.com/mattermost/mattermost-server/model"
 )
 
@@ -37,7 +36,7 @@ func uploadPlugin(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if !app.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
+	if !c.App.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
 		c.SetPermissionError(model.PERMISSION_MANAGE_SYSTEM)
 		return
 	}
@@ -84,7 +83,7 @@ func getPlugins(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if !app.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
+	if !c.App.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
 		c.SetPermissionError(model.PERMISSION_MANAGE_SYSTEM)
 		return
 	}
@@ -109,7 +108,7 @@ func removePlugin(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if !app.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
+	if !c.App.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
 		c.SetPermissionError(model.PERMISSION_MANAGE_SYSTEM)
 		return
 	}
@@ -156,7 +155,7 @@ func activatePlugin(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if !app.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
+	if !c.App.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
 		c.SetPermissionError(model.PERMISSION_MANAGE_SYSTEM)
 		return
 	}
@@ -180,7 +179,7 @@ func deactivatePlugin(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if !app.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
+	if !c.App.SessionHasPermissionTo(c.Session, model.PERMISSION_MANAGE_SYSTEM) {
 		c.SetPermissionError(model.PERMISSION_MANAGE_SYSTEM)
 		return
 	}