Creating a Dynamic Contract (Simple)

A walkthrough on the basics of a Dynamic Contract's structure.

Let's create a test contract that allows three variables - name, number and tuple - to be changed by the owner of the contract, as well as perform basic operations with structs/tuples and event emissions. We will call this contract SimpleContract (which just so happens to be already implemented by the project due to internal testing purposes, but you can do it yourself by hand - check the simplecontract.{h,cpp,sol} files for reference).

Creating the Files

First we need to create the contract's header (.h) and source (.cpp) files, as is customary in C++ development - the header will contain the definition of our contract class, and the source will contain the implementation details.

Go to your local testnet's root folder, into the src/contract/templates subfolder, and create two new files - simplecontract.h and simplecontract.cpp. Those files will contain the declaration and definition of your contract's logic, respectively.

Then, add both files to the CMakeLists.txt file in the same folder, so they can be compiled with the project:

set(CONTRACT_HEADERS
  # ...
  ${CMAKE_SOURCE_DIR}/src/contract/templates/simplecontract.h
  # ...
)
set(CONTRACT_SOURCES
  # ...
  ${CMAKE_SOURCE_DIR}/src/contract/templates/simplecontract.cpp
  # ...
)

In the following subchapters, we'll implement the header file first, then the source file, write some tests and finally deploy the contract alongside the blockchain.