diff --git a/app/controllers/projects/network_controller.rb b/app/controllers/projects/network_controller.rb
index e29e5994c4b..e808c9c7343 100644
--- a/app/controllers/projects/network_controller.rb
+++ b/app/controllers/projects/network_controller.rb
@@ -5,16 +5,16 @@ class Projects::NetworkController < Projects::ApplicationController
   before_action :require_non_empty_project
   before_action :assign_ref_vars
   before_action :authorize_download_code!
+  before_action :assign_extended_sha1
 
   def show
     @url = namespace_project_network_path(@project.namespace, @project, @ref, @options.merge(format: :json))
     @commit_url = namespace_project_commit_path(@project.namespace, @project, 'ae45ca32').gsub("ae45ca32", "%s")
-    @commit = @repo.commit(params[:extended_sha1]) if params[:extended_sha1].present?
 
     respond_to do |format|
       format.html do
-        if params[:extended_sha1].present? && !@commit
-          flash.now[:alert] = "Git revision '#{params[:extended_sha1]}' does not exist."
+        if @options[:extended_sha1] && !@commit
+          flash.now[:alert] = "Git revision '#{@options[:extended_sha1]}' does not exist."
         end
       end
 
@@ -23,4 +23,11 @@ class Projects::NetworkController < Projects::ApplicationController
       end
     end
   end
+
+  def assign_extended_sha1
+    return if params[:extended_sha1].blank?
+
+    @options[:extended_sha1] = params[:extended_sha1]
+    @commit = @repo.commit(@options[:extended_sha1])
+  end
 end
diff --git a/app/views/projects/network/show.html.haml b/app/views/projects/network/show.html.haml
index af565873444..d8951e69242 100644
--- a/app/views/projects/network/show.html.haml
+++ b/app/views/projects/network/show.html.haml
@@ -8,7 +8,7 @@
   .project-network
     .controls
       = form_tag namespace_project_network_path(@project.namespace, @project, @id), method: :get, class: 'form-inline network-form' do |f|
-        = text_field_tag :extended_sha1, params[:extended_sha1], placeholder: "Git revision", class: 'search-input form-control input-mx-250 search-sha'
+        = text_field_tag :extended_sha1, @options[:extended_sha1], placeholder: "Git revision", class: 'search-input form-control input-mx-250 search-sha'
         = button_tag class: 'btn btn-success' do
           = icon('search')
         .inline.prepend-left-20