From e3d86984cdc3079ad448afd5022d395f0323f414 Mon Sep 17 00:00:00 2001
From: Ben Schumacher <ben.schumacher@mattermost.com>
Date: Thu, 4 Apr 2024 10:28:31 +0200
Subject: [PATCH] [MM-54994] Use local requests instead of HTTP requests in the
 flow library (#26471)

---
 .../pluginapi/experimental/flow/flow.go       | 24 +++++++++++++++----
 .../pluginapi/experimental/flow/handler.go    |  4 ++--
 .../pluginapi/experimental/flow/step.go       |  2 +-
 3 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/server/public/pluginapi/experimental/flow/flow.go b/server/public/pluginapi/experimental/flow/flow.go
index 036b1e6099..98fae8dcb7 100644
--- a/server/public/pluginapi/experimental/flow/flow.go
+++ b/server/public/pluginapi/experimental/flow/flow.go
@@ -27,9 +27,11 @@ type Flow struct {
 
 	name      Name
 	api       *pluginapi.Client
-	pluginURL string
+	pluginID  string
 	botUserID string
 
+	siteURL string
+
 	steps map[Name]Step
 	index []Name
 	done  func(userID string, state State) error
@@ -40,14 +42,28 @@ type Flow struct {
 // NewFlow creates a new flow using direct messages with the user.
 //
 // name must be a unique identifier for the flow within the plugin.
-func NewFlow(name Name, api *pluginapi.Client, pluginURL, botUserID string) *Flow {
+func NewFlow(name Name, api *pluginapi.Client, pluginID, botUserID string) (*Flow, error) {
+	if api == nil {
+		return nil, errors.New("API client must not be nil")
+	}
+
+	config := api.Configuration.GetConfig()
+	if config == nil {
+		return nil, errors.New("failed to fetch configuration")
+	}
+
+	if config.ServiceSettings.SiteURL == nil {
+		return nil, errors.New("please configure the Mattermost Server's SiteURL, then restart the plugin.")
+	}
+
 	return &Flow{
 		name:      name,
 		api:       api,
-		pluginURL: pluginURL,
+		pluginID:  pluginID,
 		botUserID: botUserID,
+		siteURL:   strings.TrimRight(*config.ServiceSettings.SiteURL, "/"),
 		steps:     map[Name]Step{},
-	}
+	}, nil
 }
 
 func (f *Flow) WithSteps(orderedSteps ...Step) *Flow {
diff --git a/server/public/pluginapi/experimental/flow/handler.go b/server/public/pluginapi/experimental/flow/handler.go
index 5d5e4dac01..c3444fe754 100644
--- a/server/public/pluginapi/experimental/flow/handler.go
+++ b/server/public/pluginapi/experimental/flow/handler.go
@@ -162,7 +162,7 @@ func (f *Flow) handle(
 
 		dialogRequest := model.OpenDialogRequest{
 			TriggerId: triggerID,
-			URL:       f.pluginURL + namePath(f.name) + "/dialog",
+			URL:       "/plugins/" + f.pluginID + namePath(f.name) + "/dialog",
 			Dialog:    processDialog(b.Dialog, state.AppState),
 		}
 		dialogRequest.Dialog.State = fmt.Sprintf("%v,%v", fromName, selectedButton)
@@ -205,6 +205,6 @@ func (f *Flow) processButtonPostActions(post *model.Post) {
 		if a.Integration == nil {
 			a.Integration = &model.PostActionIntegration{}
 		}
-		a.Integration.URL = f.pluginURL + namePath(f.name) + "/button"
+		a.Integration.URL = "/plugins/" + f.pluginID + namePath(f.name) + "/button"
 	}
 }
diff --git a/server/public/pluginapi/experimental/flow/step.go b/server/public/pluginapi/experimental/flow/step.go
index c4b5e829c8..3f5d32e77c 100644
--- a/server/public/pluginapi/experimental/flow/step.go
+++ b/server/public/pluginapi/experimental/flow/step.go
@@ -189,7 +189,7 @@ func (f *Flow) processAttachment(attachment *model.SlackAttachment) *model.Slack
 			if u.Host != "" && (u.Scheme == "http" || u.Scheme == "https") {
 				a.ImageURL = attachment.ImageURL
 			} else {
-				a.ImageURL = f.pluginURL + "/" + strings.TrimPrefix(attachment.ImageURL, "/")
+				a.ImageURL = fmt.Sprintf("%s/plugins/%s/%s", f.siteURL, f.pluginID, strings.TrimPrefix(attachment.ImageURL, "/"))
 			}
 		}
 	}