Fixes #413.

Author: simonbrowndotje

changelog.md

@@ -2,6 +2,7 @@
 
 ## v4.0.1 (unreleased)
 
+- structurizr-client: Fixes https://github.com/structurizr/java/issues/413 (Cannot push to main branch, when branch feature is activated).
 - structurizr-dsl: Allows archetypes to be used via workspace extension.
 - structurizr-dsl: Adds archetype support for custom elements.
 - structurizr-dsl: Fixes https://github.com/structurizr/java/issues/399 (Archetype tags sometimes missing).

structurizr-client/src/main/java/com/structurizr/api/WorkspaceApiClient.java

@@ -313,7 +313,7 @@ public void putWorkspace(long workspaceId, Workspace workspace) throws Structuri
             workspace.setLastModifiedUser(getUser());
 
             HttpPut httpPut;
-            if (StringUtils.isNullOrEmpty(branch)) {
+            if (StringUtils.isNullOrEmpty(branch) || branch.equalsIgnoreCase(MAIN_BRANCH)) {
                 httpPut = new HttpPut(url + WORKSPACE_PATH + "/" + workspaceId);
             } else {
                 httpPut = new HttpPut(url + WORKSPACE_PATH + "/" + workspaceId + "/branch/" + branch);