return default workspace constant value if master could not get it fr…

…om lmdb

kong/db/dao/workspaces.lua

@@ -6,6 +6,7 @@ local lmdb = require("resty.lmdb")
 
 
 local DECLARATIVE_DEFAULT_WORKSPACE_KEY = constants.DECLARATIVE_DEFAULT_WORKSPACE_KEY
+local DECLARATIVE_DEFAULT_WORKSPACE_ID = constants.DECLARATIVE_DEFAULT_WORKSPACE_ID
 
 
 function Workspaces:truncate()
@@ -27,12 +28,13 @@ end
 
 function Workspaces:select_by_name(key, options)
   if kong.configuration.database == "off" and key == "default" then
-    -- We can ensure that when starting in dbless mode, lmdb will by default
-    -- insert a 'default' workspace. If this Kong is a dataplane, it will later
-    -- synchronize the configuration from the CP and overwrite this default one.
+    -- TODO: Currently, only Kong workers load the declarative config into lmdb.
+    -- The Kong master doesn't get the default workspace from lmdb, so we
+    -- return the default constant value. It would be better to have the
+    -- Kong master load the declarative config into lmdb in the future.
     --
     -- it should be a table, not a single string
-    return { id = lmdb.get(DECLARATIVE_DEFAULT_WORKSPACE_KEY), }
+    return { id = lmdb.get(DECLARATIVE_DEFAULT_WORKSPACE_KEY) or DECLARATIVE_DEFAULT_WORKSPACE_ID, }
   end
 
   return self.super.select_by_name(self, key, options)

kong/db/strategies/off/init.lua

@@ -40,8 +40,8 @@ local UNINIT_WORKSPACE_ID = "00000000-0000-0000-0000-000000000000"
 
 local function get_default_workspace()
   if kong.default_workspace == UNINIT_WORKSPACE_ID then
-    local res = assert(kong.db.workspaces:select_by_name("default"))
-    kong.default_workspace = res.id
+    local res = kong.db.workspaces:select_by_name("default")
+    kong.default_workspace = assert(res and res.id)
   end
 
   return kong.default_workspace