Showing posts from January, 2018

Making of Message Gateway with Kafka - Part 2

Assembling multi-part messages using KafkaStreams API What and why?  In previous post we gave general overview of the product we are building - message gateway. In this post we are going to describe how we process message parts and assemble whole messages. One issue with  SMS is that messages are limited to 160 characters. The way SMS protocol overrides that limitation is by using so called "Long SMS messages". Basically, multiple SMS messages are sent as parts of final message which is displayed to end user only after all parts arrive. SMPP protocol supports this feature, so we need to support it in our product as well. Since we are not limited to SMPP  protocol only, we made our own abstraction of multi-part messages. It boils down to this: every message is multi-part and can have one or more parts. Messages with one part are logically not multi-part, but from technical perspective it's easier to treat all messages in same way, so we don't make structural di

Making of Message Gateway with Kafka - Part 1

The beginning  Here at Inovativni trendovi  we recently started new project that I 'm very excited about. The reason for my excitement is that we are using Apache Kafka on it. We also decided to write it in Kotlin , so this is going to be superfun! Spring-boot based project written in Kotlin, using Apache Kafka. Who can ask for more! Few words about the product we are building... It is SMS message gateway that receives messages from customers , routes and sends them to appropriate SMS service provider which delivers them to end user. It receives delivery reports from service suppliers and sends them back to customer that sent original message. Messages can also be sent in other direction - from end user to customer. The product has to provide high availability and able to handle high load, in other words horizontal scaling  must be supported. Primary protocol used between customers and our product as well as between our product and SMS service providers is SMPP . Thi