feat: mock device extension

[adamdama]

What

A ripple extension that supports setting up a WebSocket server to stand in for a device.
Thunder connection retries during boot

Why

To support unit, component and (contract) provider verification testing in a containerised or desktop environment without access to a hardware device.

Additionally to support development of certain features which do not rely on a real device to function but require certain responses from the lower layers of the software stack.

How

The premise of the mock device is simple. A WebSocket server with a registry of known requests and the responses we expect for each of those requests. When a request is made to the WebSocket server the incoming request is compared to the registry and if found the corresponding responses are sent back. If the request is unrecognised then nothing is sent back.

The extension is presented in two parts: a channel and a JSON-RPC extension. The channel holds the running WebSocket server that acts as the device and the JSON-RPC extension offers a control plane for the data within the server.

During extension loading a WebSocket server is started listening on the same port that the Thunder extension expects Thunder to be present on. In order to support this, connection retries have added to the Thunder SDK so that if the WebSocket server is not available immediately additional attempts to connect will be made.

The extension loads the initial state from a JSON file found in at a predetermined location. This is essential to get Ripple to boot up without crashing as certain requests and made to a device immediately after establishing the connection.

Once Ripple is running there are JSON-RPC methods which can be used to:

• add or overwrite requests in the mock data registry
• remove requests from the registry
• emit an event not yet implmented

Test

Set up a manifest as per the included docs.
See docs for usage and try some of the patterns.

Checklist

• I have self-reviewed this PR
• I have added tests that prove the feature works or the fix is effective

[github-actions]

Package	Line Rate	Health
distributor.general.src	2%	❌
core.main.src.service	30%	❌
core.main.src.firebolt.handlers	2%	❌
device.thunder_ripple_sdk.src.processors.events	0%	❌
core.sdk.src.api.observability	48%	➖
core.sdk.src.extn	83%	✔
core.main.src	0%	❌
core.main.src.state	19%	❌
core.launcher.src	0%	❌
device.thunder_ripple_sdk.src	16%	❌
core.sdk.src.api.gateway	48%	➖
core.main.src.processor	0%	❌
core.main.src.bootstrap	0%	❌
core.main.src.bootstrap.manifest	0%	❌
core.main.src.bootstrap.extn	0%	❌
core.main.src.processor.storage	0%	❌
core.tdk.src.gateway	100%	✔
core.sdk.src.extn.ffi	80%	✔
core.main.src.service.extn	38%	➖
device.thunder_ripple_sdk.src.client	78%	✔
openrpc_validator.src	90%	✔
device.thunder.src	0%	❌
device.thunder_ripple_sdk.src.events	4%	❌
device.thunder.src.bootstrap	0%	❌
core.main.src.utils	13%	❌
core.sdk.src.api.distributor	84%	✔
core.sdk.src.framework	74%	➖
core.sdk.src.api	66%	➖
core.main.src.firebolt	1%	❌
core.main.src.state.cap	44%	➖
core.sdk.src.utils	53%	➖
core.sdk.src.api.firebolt	50%	➖
core.launcher.src.manager	7%	❌
core.sdk.src.api.manifest	55%	➖
core.main.src.service.apps	43%	➖
core.sdk.src.extn.client	91%	✔
core.sdk.src.api.device	59%	➖
core.tdk.src.utils	0%	❌
device.mock_device.src	52%	➖
device.thunder_ripple_sdk.src.bootstrap	0%	❌
device.thunder_ripple_sdk.src.processors	4%	❌
Summary	35% (11910 / 33819)	➖

Minimum allowed line rate is 33%