lib/j7w1/sns_push_client.rb in j7w1-0.0.25 vs lib/j7w1/sns_push_client.rb in j7w1-0.0.26

@@ -2,12 +2,15 @@
   module SNSPushClient
     def create_sns_client(configuration = J7W1.configuration)
       AWS::SNS.new configuration.account
     end
 
-    APNS_MAX_MESSAGE_SIZE = 40
+    APNS_MAX_PAYLOAD = 256
 
+    SHORTEN_REPLACEMENT = '...'.freeze
+    SHORTEN_REPLACEMENT_LENGTH = SHORTEN_REPLACEMENT.length
+
     INPUT_PAYLOAD_TABLE = {
       ios: {
         message: :alert,
         badge: :badge,
         sound: :sound,
@@ -85,10 +88,24 @@
       sns_client.client.delete_endpoint(endpoint_arn: device_endpoint_arn)
     rescue
       nil
     end
 
+    def create_topic(name, options)
+      sns_client = options[:sns_client]
+      sns_client ||= create_sns_client(sns_configuration || J7W1.configuration)
+
+      sns_client.topics.create name
+    end
+
+    def subscribe_topic(topic_name, endpoint_arn, options)
+      sns_client = options[:sns_client]
+      sns_client ||= create_sns_client(sns_configuration || J7W1.configuration)
+
+      sns_client.topics[name]
+    end
+
     def push(endpoint_arn, platform, options = {})
       return unless endpoint_arn && platform
 
       message = options[:message]
       badge = options[:badge]
@@ -131,19 +148,40 @@
 
     def ios_payload_for(message_value, data)
       prefix = J7W1.configuration.ios_endpoint.sandbox? ?
           :APNS_SANDBOX : :APNS
 
-      if message_value[:message] && message_value[:message].length > APNS_MAX_MESSAGE_SIZE
-        message_value[:message] = message_value[:message][0...(APNS_MAX_MESSAGE_SIZE - 3)] + '...'
-      end
-
       content = {
           aps: message_content(message_value, platform: :ios),
       }
       content.merge! data: data if data
 
-      {prefix => content.to_json}
+      {prefix => ios_truncated_payload(content)}
+    end
+
+    def ios_truncated_payload(data)
+      payload = data.to_json
+
+      # Truncation is skipped when the payload is sufficiently lightweight.
+      return payload if (limit_break = payload.bytesize - APNX_MAX_PAYLOAD) >= 0
+
+      # Raise error if shortening of the alert cannot make the payload sufficiently short.
+      size_to_reduce = limit_break + SHORTEN_REPLACEMENT_LENGTH
+      raise "Payload is too heavy (#{payload.length})" unless
+        data[:alert] && data[:alert].bytesize > size_to_reduce
+
+      # Chopping the alert from its last -> first to avoid destroying the character's border
+      # and keep its content as long as possible.
+      chopped_length = 0
+      chopped_count = 0
+      while chopped_length < size_to_reduce
+        chopped_length += data[:alert][-1].bytesize
+        chopped_count += 1
+      end
+      data[:alert][-chopped_count..-1] = SHORTEN_REPLACEMENT
+      # Problem won't be occur because at least a character is truncated.
+
+      data.to_json
     end
 
     def android_payload_for(message_value, data)
       message_value.merge!(data: data)
       {