Crate shotover 

This library allows the creation of custom shotover transforms.

There are two consumers of this library:

Custom Transforms

To create a custom transform you need to implement these traits:

• transforms::TransformConfig - Defines what configuration fields the transform has in the topology.yaml.
• transforms::TransformBuilder - Defines how to build the Transform for a new incoming connection. Only one instance is created over shotovers runtime.
• transforms::Transform - Defines the transformation logic of the transform. A new instance is created per incoming connection.

Simple transforms can implement all of these onto a single struct but generally you need seperate structs for each.

The shotover binary

All custom transforms the user wants to use are statically compiled into a single binary. The crate for this binary is very simple, it just consists of a main.rs like:

shotover::import_transform!(transform_crate::TransformConfig);

fn main() {
    shotover::runner::Shotover::new().run_block();
}

Modules

codec

Codec types to use for connecting to a DB in a sink transform

config

Config types, used for serializing/deserializing shotover configuration files

connection

All Sink transforms use SinkConnection for their outgoing connections.

frame

parsed AST-like representations of messages

message

Message and supporting types - used to hold a message/query/result going between the client and database

runner

Tools for initializing shotover in the final binary.

sources

Sources used to listen for connections and send/recieve with the client.

tcp

Use to establish a TCP connection to a DB in a sink transform

tls

Use to establish a TLS connection to a DB in a sink transform

transforms

Various types required for defining a transform

Macros

import_transform

Imports a custom transform into the shotover binary.