From b59c4c34c5cc5ca240152237b48a555f5db4e7dd Mon Sep 17 00:00:00 2001
From: Kjell Winblad <kjellwinblad@gmail.com>
Date: Wed, 4 Jan 2023 16:00:42 +0100
Subject: [PATCH] fix(Bridge REST API): no feedback when deleting bridge

This fixes https://emqx.atlassian.net/browse/EMQX-8648. The issue
described in `EMQX-8648` is that when deleting a non-existing bridge the
server gives a success response. See below:

```
curl --head -u admin:public2 -X 'DELETE' 'http://localhost:18083/api/v5/bridges/webhook:i_do_not_exist'
HTTP/1.1 204 No Content
date: Tue, 03 Jan 2023 16:59:01 GMT
server: Cowboy
```

After the fix, deleting a non existing bridge will give the following
response:

```
HTTP/1.1 404 Not Found
content-length: 49
content-type: application/json
date: Thu, 05 Jan 2023 12:40:35 GMT
server: Cowboy
```

Closes: EMQX-8648
---
 apps/emqx_bridge/src/emqx_bridge_api.erl      | 30 +++++++++++--------
 .../test/emqx_bridge_api_SUITE.erl            |  9 ++++++
 changes/v5.0.14/fix-8648.en.md                |  1 +
 3 files changed, 28 insertions(+), 12 deletions(-)
 create mode 100644 changes/v5.0.14/fix-8648.en.md

diff --git a/apps/emqx_bridge/src/emqx_bridge_api.erl b/apps/emqx_bridge/src/emqx_bridge_api.erl
index 0d0d2e9ad..cf39ebf14 100644
--- a/apps/emqx_bridge/src/emqx_bridge_api.erl
+++ b/apps/emqx_bridge/src/emqx_bridge_api.erl
@@ -328,6 +328,7 @@ schema("/bridges/:id") ->
             responses => #{
                 204 => <<"Bridge deleted">>,
                 400 => error_schema(['INVALID_ID'], "Update bridge failed"),
+                404 => error_schema('NOT_FOUND', "Bridge not found"),
                 403 => error_schema('FORBIDDEN_REQUEST', "Forbidden operation"),
                 503 => error_schema('SERVICE_UNAVAILABLE', "Service unavailable")
             }
@@ -433,19 +434,24 @@ schema("/nodes/:node/bridges/:id/operation/:operation") ->
         end,
     ?TRY_PARSE_ID(
         Id,
-        case emqx_bridge:check_deps_and_remove(BridgeType, BridgeName, AlsoDeleteActs) of
+        case emqx_bridge:lookup(BridgeType, BridgeName) of
             {ok, _} ->
-                204;
-            {error, {rules_deps_on_this_bridge, RuleIds}} ->
-                {403,
-                    error_msg(
-                        'FORBIDDEN_REQUEST',
-                        {<<"There're some rules dependent on this bridge">>, RuleIds}
-                    )};
-            {error, timeout} ->
-                {503, error_msg('SERVICE_UNAVAILABLE', <<"request timeout">>)};
-            {error, Reason} ->
-                {500, error_msg('INTERNAL_ERROR', Reason)}
+                case emqx_bridge:check_deps_and_remove(BridgeType, BridgeName, AlsoDeleteActs) of
+                    {ok, _} ->
+                        204;
+                    {error, {rules_deps_on_this_bridge, RuleIds}} ->
+                        {403,
+                            error_msg(
+                                'FORBIDDEN_REQUEST',
+                                {<<"There're some rules dependent on this bridge">>, RuleIds}
+                            )};
+                    {error, timeout} ->
+                        {503, error_msg('SERVICE_UNAVAILABLE', <<"request timeout">>)};
+                    {error, Reason} ->
+                        {500, error_msg('INTERNAL_ERROR', Reason)}
+                end;
+            {error, not_found} ->
+                {404, error_msg('NOT_FOUND', <<"Bridge not found">>)}
         end
     ).
 
diff --git a/apps/emqx_bridge/test/emqx_bridge_api_SUITE.erl b/apps/emqx_bridge/test/emqx_bridge_api_SUITE.erl
index 60f770df8..8f7978f40 100644
--- a/apps/emqx_bridge/test/emqx_bridge_api_SUITE.erl
+++ b/apps/emqx_bridge/test/emqx_bridge_api_SUITE.erl
@@ -303,6 +303,15 @@ t_http_crud_apis(Config) ->
         },
         jsx:decode(ErrMsg2)
     ),
+    %% Deleting a non-existing bridge should result in an error
+    {ok, 404, ErrMsg3} = request(delete, uri(["bridges", BridgeID]), []),
+    ?assertMatch(
+        #{
+            <<"code">> := _,
+            <<"message">> := <<"Bridge not found">>
+        },
+        jsx:decode(ErrMsg3)
+    ),
     ok.
 
 t_check_dependent_actions_on_delete(Config) ->
diff --git a/changes/v5.0.14/fix-8648.en.md b/changes/v5.0.14/fix-8648.en.md
new file mode 100644
index 000000000..ac608a2e1
--- /dev/null
+++ b/changes/v5.0.14/fix-8648.en.md
@@ -0,0 +1 @@
+When deleting a non-existing bridge the server gave a success response. This has been fixed so that the server instead gives an error response when the user attempts to delete a non-existing bridge.