[MM-42191]: Include deleted posts (#19985)

* MM-42191: Include deleted posts: Add includeDeleted query parameter for getPostsForChannel

* MM-42191: Fix error typo for includeDeleted query parameter

* MM-42191: Include deleted posts: Set permission error when deleted posts are requested by non system admins

* MM-42191: Include deleted posts: Refactor replyCountSubQuery and conditions when includeDeleted is not presented, refactor getRootPosts

* MM-42191: Include deleted posts: Refactor getRootPosts function along with skipFetchThreads and includeDeleted

* MM-42191: Include deleted posts: Rename includeDeleted to include_deleted param

* MM-42191: Include deleted posts: Fix failed posts unit tests

* MM-42191: Include deleted posts: Add missing include deleted option in multiple queries

* MM-42191: Include deleted posts: Add tests for include deleted option in TestGetPostsForChannel, TestGetPostsBefore, TestGetPostsAfter

* MM-42191: include deleted posts: Add tests cases for post store test

* MM-42191: Include deleted posts: Add extra unit test to ensure not returning deleted posts when IncludeDelete is false

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

model/client4.go

@@ -3925,11 +3925,15 @@ func (c *Client4) GetPostThreadWithOpts(postID string, etag string, opts GetPost
 }
 
 // GetPostsForChannel gets a page of posts with an array for ordering for a channel.
-func (c *Client4) GetPostsForChannel(channelId string, page, perPage int, etag string, collapsedThreads bool) (*PostList, *Response, error) {
+func (c *Client4) GetPostsForChannel(channelId string, page, perPage int, etag string, collapsedThreads bool, includeDeleted bool) (*PostList, *Response, error) {
 	query := fmt.Sprintf("?page=%v&per_page=%v", page, perPage)
 	if collapsedThreads {
 		query += "&collapsedThreads=true"
 	}
+
+	if includeDeleted {
+		query += "&include_deleted=true"
+	}
 	r, err := c.DoAPIGet(c.channelRoute(channelId)+"/posts"+query, etag)
 	if err != nil {
 		return nil, BuildResponse(r), err
@@ -4050,11 +4054,14 @@ func (c *Client4) GetPostsSince(channelId string, time int64, collapsedThreads b
 }
 
 // GetPostsAfter gets a page of posts that were posted after the post provided.
-func (c *Client4) GetPostsAfter(channelId, postId string, page, perPage int, etag string, collapsedThreads bool) (*PostList, *Response, error) {
+func (c *Client4) GetPostsAfter(channelId, postId string, page, perPage int, etag string, collapsedThreads bool, includeDeleted bool) (*PostList, *Response, error) {
 	query := fmt.Sprintf("?page=%v&per_page=%v&after=%v", page, perPage, postId)
 	if collapsedThreads {
 		query += "&collapsedThreads=true"
 	}
+	if includeDeleted {
+		query += "&include_deleted=true"
+	}
 	r, err := c.DoAPIGet(c.channelRoute(channelId)+"/posts"+query, etag)
 	if err != nil {
 		return nil, BuildResponse(r), err
@@ -4071,11 +4078,14 @@ func (c *Client4) GetPostsAfter(channelId, postId string, page, perPage int, eta
 }
 
 // GetPostsBefore gets a page of posts that were posted before the post provided.
-func (c *Client4) GetPostsBefore(channelId, postId string, page, perPage int, etag string, collapsedThreads bool) (*PostList, *Response, error) {
+func (c *Client4) GetPostsBefore(channelId, postId string, page, perPage int, etag string, collapsedThreads bool, includeDeleted bool) (*PostList, *Response, error) {
 	query := fmt.Sprintf("?page=%v&per_page=%v&before=%v", page, perPage, postId)
 	if collapsedThreads {
 		query += "&collapsedThreads=true"
 	}
+	if includeDeleted {
+		query += "&include_deleted=true"
+	}
 	r, err := c.DoAPIGet(c.channelRoute(channelId)+"/posts"+query, etag)
 	if err != nil {
 		return nil, BuildResponse(r), err

model/permission.go

@@ -73,6 +73,7 @@ var PermissionDeleteOthersEmojis *Permission
 var PermissionCreatePost *Permission
 var PermissionCreatePostPublic *Permission
 var PermissionCreatePostEphemeral *Permission
+var PermissionReadDeletedPosts *Permission
 var PermissionEditPost *Permission
 var PermissionEditOthersPosts *Permission
 var PermissionDeletePost *Permission
@@ -708,6 +709,12 @@ func initializePermissions() {
 		"authentication.permissions.create_post_ephemeral.description",
 		PermissionScopeChannel,
 	}
+	PermissionReadDeletedPosts = &Permission{
+		"read_deleted_posts",
+		"authentication.permissions.read_deleted_posts.name",
+		"authentication.permissions.read_deleted_posts.description",
+		PermissionScopeChannel,
+	}
 	PermissionEditPost = &Permission{
 		"edit_post",
 		"authentication.permissions.edit_post.name",
@@ -2302,6 +2309,7 @@ func initializePermissions() {
 		PermissionCreatePost,
 		PermissionCreatePostPublic,
 		PermissionCreatePostEphemeral,
+		PermissionReadDeletedPosts,
 		PermissionEditPost,
 		PermissionEditOthersPosts,
 		PermissionDeletePost,

model/post.go

@@ -304,6 +304,7 @@ type GetPostsOptions struct {
 	FromPost                 string // PostId after which to send the items
 	FromCreateAt             int64  // CreateAt after which to send the items
 	Direction                string // Only accepts up|down. Indicates the order in which to send the items.
+	IncludeDeleted           bool
 }
 
 type PostCountOptions struct {