allow to disable transactions in the configurations to avoid errors when running on backends that don't support transactions

Author: Maik Kuntze

lib/jsonapi/configuration.rb

@@ -21,6 +21,7 @@ class Configuration
                 :top_level_meta_record_count_key,
                 :top_level_meta_include_page_count,
                 :top_level_meta_page_count_key,
+                :allow_transactions,
                 :exception_class_whitelist,
                 :always_include_to_one_linkage_data,
                 :always_include_to_many_linkage_data,
@@ -80,6 +81,10 @@ def initialize
       # for a Resource.
       self.default_processor_klass = JSONAPI::Processor
 
+      # Allows transactions for creating and updating records
+      # Set this to false if your backend does not support transactions (e.g. Mongodb)
+      self.allow_transactions = true
+
       # Formatter Caching
       # Set to false to disable caching of string operations on keys and links.
       self.cache_formatters = true
@@ -172,6 +177,8 @@ def default_processor_klass=(default_processor_klass)
 
     attr_writer :top_level_meta_page_count_key
 
+    attr_writer :allow_transactions
+
     attr_writer :exception_class_whitelist
 
     attr_writer :always_include_to_one_linkage_data

lib/jsonapi/operation_dispatcher.rb

@@ -16,9 +16,10 @@ def process(operations)
       # Use transactions if more than one operation and if one of the operations can be transactional
       # Even if transactional transactions won't be used unless the derived OperationsProcessor supports them.
       transactional = false
+
       operations.each do |operation|
         transactional |= operation.transactional?
-      end
+      end if JSONAPI.configuration.allow_transactions
 
       transaction(transactional) do
         # Links and meta data global to the set of operations