PLT-3105 Files table migration (#4068)

* Implemented initial changes for files table

* Removed *_benchmark_test.go files

* Re-implemented GetPublicFile and added support for old path

* Localization for files table

* Moved file system code into utils package

* Finished server-side changes and added initial upgrade script

* Added getPostFiles api

* Re-add Extension and HasPreviewImage fields to FileInfo

* Removed unused translation

* Fixed merge conflicts left over after permissions changes

* Forced FileInfo.extension to be lower case

* Changed FileUploadResponse to contain the FileInfos instead of FileIds

* Fixed permissions on getFile* calls

* Fixed notifications for file uploads

* Added initial version of client code for files changes

* Permanently added FileIds field to Post object and removed Post.HasFiles

* Updated PostStore.Update to be usable in more circumstances

* Re-added Filenames field and switched file migration to be entirely lazy-loaded

* Increased max listener count for FileStore

* Removed unused fileInfoCache

* Moved file system code back into api

* Removed duplicate test case

* Fixed unit test running on ports other than 8065

* Renamed HasPermissionToPostContext to HasPermissionToChannelByPostContext

* Refactored handleImages to make it more easily understandable

* Renamed getPostFiles to getFileInfosForPost

* Re-added pre-FileIds posts to analytics

* Changed files to be saved as their ids as opposed to id/filename.ext

* Renamed FileInfo.UserId to FileInfo.CreatorId

* Fixed detection of language in CodePreview

* Fixed switching between threads in the RHS not loading new files

* Add serverside protection against a rare bug where the client sends the same file twice for a single post

* Refactored the important parts of uploadFile api call into a function that can be called without a web context

store/sql_post_store.go

@@ -32,6 +32,7 @@ func NewSqlPostStore(sqlStore *SqlStore) PostStore {
 		table.ColMap("Hashtags").SetMaxSize(1000)
 		table.ColMap("Props").SetMaxSize(8000)
 		table.ColMap("Filenames").SetMaxSize(4000)
+		table.ColMap("FileIds").SetMaxSize(150)
 	}
 
 	return s
@@ -94,42 +95,39 @@ func (s SqlPostStore) Save(post *model.Post) StoreChannel {
 	return storeChannel
 }
 
-func (s SqlPostStore) Update(oldPost *model.Post, newMessage string, newHashtags string) StoreChannel {
+func (s SqlPostStore) Update(newPost *model.Post, oldPost *model.Post) StoreChannel {
 	storeChannel := make(StoreChannel, 1)
 
 	go func() {
 		result := StoreResult{}
 
-		editPost := *oldPost
-		editPost.Message = newMessage
-		editPost.UpdateAt = model.GetMillis()
-		editPost.Hashtags = newHashtags
+		newPost.UpdateAt = model.GetMillis()
 
-		oldPost.DeleteAt = editPost.UpdateAt
-		oldPost.UpdateAt = editPost.UpdateAt
+		oldPost.DeleteAt = newPost.UpdateAt
+		oldPost.UpdateAt = newPost.UpdateAt
 		oldPost.OriginalId = oldPost.Id
 		oldPost.Id = model.NewId()
 
-		if result.Err = editPost.IsValid(); result.Err != nil {
+		if result.Err = newPost.IsValid(); result.Err != nil {
 			storeChannel <- result
 			close(storeChannel)
 			return
 		}
 
-		if _, err := s.GetMaster().Update(&editPost); err != nil {
-			result.Err = model.NewLocAppError("SqlPostStore.Update", "store.sql_post.update.app_error", nil, "id="+editPost.Id+", "+err.Error())
+		if _, err := s.GetMaster().Update(newPost); err != nil {
+			result.Err = model.NewLocAppError("SqlPostStore.Update", "store.sql_post.update.app_error", nil, "id="+newPost.Id+", "+err.Error())
 		} else {
 			time := model.GetMillis()
-			s.GetMaster().Exec("UPDATE Channels SET LastPostAt = :LastPostAt  WHERE Id = :ChannelId", map[string]interface{}{"LastPostAt": time, "ChannelId": editPost.ChannelId})
+			s.GetMaster().Exec("UPDATE Channels SET LastPostAt = :LastPostAt  WHERE Id = :ChannelId", map[string]interface{}{"LastPostAt": time, "ChannelId": newPost.ChannelId})
 
-			if len(editPost.RootId) > 0 {
-				s.GetMaster().Exec("UPDATE Posts SET UpdateAt = :UpdateAt WHERE Id = :RootId", map[string]interface{}{"UpdateAt": time, "RootId": editPost.RootId})
+			if len(newPost.RootId) > 0 {
+				s.GetMaster().Exec("UPDATE Posts SET UpdateAt = :UpdateAt WHERE Id = :RootId", map[string]interface{}{"UpdateAt": time, "RootId": newPost.RootId})
 			}
 
 			// mark the old post as deleted
 			s.GetMaster().Insert(oldPost)
 
-			result.Data = &editPost
+			result.Data = newPost
 		}
 
 		storeChannel <- result
@@ -972,7 +970,7 @@ func (s SqlPostStore) AnalyticsPostCount(teamId string, mustHaveFile bool, mustH
 		}
 
 		if mustHaveFile {
-			query += " AND Posts.Filenames != '[]'"
+			query += " AND (Posts.FileIds != '[]' OR Posts.Filenames != '[]')"
 		}
 
 		if mustHaveHashtag {