Kafka Calculator

A basic calculator that works with kafka.

Usage:

Note

Remember to change kafkaconfig.json to suit your dev environment.

After building, run these commands in the build directory:

Consumer: ./kafka-consumer --config_path ../kafkaconfig.json

Producer: ./kafka-producer add 1 2 --config_path ../kafkaconfig.json

How does this work?

Calculator

The calculator class has basic math functions that work with Integers. The GNU MP Library is used under the hood for multiple precision arithmetic. The class has an overloaded function for all operations to differentiate between strings and numbers that uses C++20 concepts to check what overload to use at compile time.

The factorial function uses all available threads to divide it into num / num_threads steps which are then separately calculated by separate threads.

Kafka Connection

The producer/consumer executables deal with the Kafka part of the project, they require a config file to run. An example is provided the project by the name kafkaconfig.json. The consumer takes data from Kafka and uses the Calculator class to perform the operation. The data must be in JSON format that follows the following structure:

{
  "operation": 0,
  "op1": 12,
  "op2": 12
}

Where operation is an int that maps to the enum class that has the following mapping:

ADD -> 0
SUB -> 1
MUL -> 2
DIV -> 3
FCT -> 4

and op1 & op2 are the operands on which the operation is to be performed.

Note:

In case of a factorial, the 2nd option doesn't matter but has to be provided.

Build instructions

Dependencies

To compile the program, you need to install CMake and the following libraries:

• GMP (The GNU Multiple Precision Arithmetic Library) for high precision math
• Boost, as it's a dependency for CppKafka
• librdkafka, which is also a dependency for CppKafka

All the other required libraries are automatically fetched and built using CMake.

Compilation

To generate the makefile(s) for the project, run cmake . -Bbuild from the root of the project, then change the current working directly to build/ and run the generator that was used by CMake, on UNIX-like systems, it's mostly either make or ninja.

Running

To run the program, you must modify the kafkaconfig.json file stored in the same folder as the executable to suit your environment. Here, you need to set:

• The Kafka broker (kafka_broker)
• The Kafka topic (kafka_topic)
• Event polling delay (poll_delay)
• Maximum queue buffering time (queue_max_time)
• Consumer group id (group_id)