fix(sbroad-cartridge): do not create stored procedures on replicas

Stored procedures creation with "box.schema.func.create" is essentially
an insert into a system space "_func". An attempt to call that API on
a replica (which usually is a RO instance) will result
in failure in role initialization.

sbroad-cartridge/cartridge/roles/sbroad-router.lua

@@ -11,8 +11,8 @@ local function init(opts) -- luacheck: no unused args
     _G.sbroad.execute = sbroad_router.execute
     _G.sbroad.trace = sbroad_router.trace
 
-    sbroad_router.init()
-    sbroad_common.init()
+    sbroad_router.init(opts.is_master)
+    sbroad_common.init(opts.is_master)
     sbroad_common.init_statistics()
 
     return true

sbroad-cartridge/cartridge/roles/sbroad-storage.lua

@@ -8,9 +8,9 @@ local function init(opts) -- luacheck: no unused args
 
     _G.sbroad.calculate_bucket_id = sbroad_common.calculate_bucket_id
 
-    sbroad_common.init()
+    sbroad_common.init(opts.is_master)
     sbroad_common.init_statistics()
-    sbroad_storage.init()
+    sbroad_storage.init(opts.is_master)
 
     return true
 end

sbroad-cartridge/src/init.lua

@@ -2,8 +2,10 @@ local cartridge = require('cartridge')
 local checks = require('checks')
 local core = require('sbroad.core')
 
-local function init ()
-    core.init()
+local function init (is_master)
+    if is_master then
+        core.init()
+    end
 end
 
 local function calculate_bucket_id(values, space_name) -- luacheck: no unused args

sbroad-cartridge/src/router.lua

@@ -39,16 +39,18 @@ _G.get_sharding_column = function()
     return cfg["executor_sharding_column"]
 end
 
-local function init()
-    box.schema.func.create(
-        'libsbroad.invalidate_coordinator_cache',
-        { if_not_exists = true, language = 'C' }
-    )
-
-    box.schema.func.create(
-        'libsbroad.dispatch_query',
-        { if_not_exists = true, language = 'C' }
-    )
+local function init(if_master)
+    if if_master then
+        box.schema.func.create(
+            'libsbroad.invalidate_coordinator_cache',
+            { if_not_exists = true, language = 'C' }
+        )
+
+        box.schema.func.create(
+            'libsbroad.dispatch_query',
+            { if_not_exists = true, language = 'C' }
+        )
+    end
 end
 
 local function invalidate_cache ()

sbroad-cartridge/src/storage.lua

@@ -24,21 +24,23 @@ _G.get_storage_cache_size_bytes = function()
     return cfg["storage_cache_size_bytes"]
 end
 
-local function init()
-    box.schema.func.create(
-        'libsbroad.execute',
-        { if_not_exists = true, language = 'C' }
-    )
-
-    box.schema.func.create(
-        'libsbroad.invalidate_segment_cache',
-        { if_not_exists = true, language = 'C' }
-    )
-
-    box.schema.func.create(
-        'libsbroad.rpc_mock',
-        { if_not_exists = true, language = 'C' }
-    )
+local function init(is_master)
+    if is_master then
+        box.schema.func.create(
+            'libsbroad.execute',
+            { if_not_exists = true, language = 'C' }
+        )
+
+        box.schema.func.create(
+            'libsbroad.invalidate_segment_cache',
+            { if_not_exists = true, language = 'C' }
+        )
+
+        box.schema.func.create(
+            'libsbroad.rpc_mock',
+            { if_not_exists = true, language = 'C' }
+        )
+    end
 end
 
 local function invalidate_cache()

sbroad-core/src/core.lua

@@ -17,8 +17,8 @@ local function init_statistics()
 end
 
 local function init()
-    init_bucket()
-    init_statistics()
+        init_bucket()
+        init_statistics()
 end
 
 return {