Summary
The Persistence Plugin Architecture is intended to address decoupling persistence implementations from the Core Data code base.
The architecture depends on Go Plugins.
Requirements
implementations live in their own repo
Reference Patterns
The basis of the requirements came out of looking at how others have solved this challenge.
Azure IoT Edge
Azure IoT Edge is organized around independently configured modules (aka containers) that are grouped to form a solution. Each module is described independently and then combined into a solution with a deployment manifest. For example, the RedisEdge module is described using the following module.json.
{
"$schema-version": "0.0.1",
"description": "RedisEdge",
"image": {
"repository": "$CONTAINER_REGISTRY_ADDRESS/redis-edge",
"tag": {
"version": "1.0.0",
"platforms": {
"amd64": "./Dockerfile.amd64",
"arm32v7": "./Dockerfile.arm32v7",
"arm64v8": "./Dockerfile.arm64v8"
}
},
"buildOptions": []
},
"language": "javascript"
}
To build a solution with this module, a deployment manifest is constructed using scripts that parse a deployment template which enumerates the modules along with their configuration. Note the use environment variables; these are populated from a .env file that is not part of the source repository.
{
"modulesContent": {
"$edgeAgent": {
"properties.desired": {
"schemaVersion": "1.0",
"runtime": {
"type": "docker",
"settings": {
"minDockerVersion": "v1.25",
"loggingOptions": "",
"registryCredentials": {
"myiotregistery": {
"username": "$CONTAINER_REGISTRY_USERNAME",
"password": "$CONTAINER_REGISTRY_PASSWORD",
"address": "$CONTAINER_REGISTRY_ADDRESS"
}
}
}
},
"systemModules": {
"edgeAgent": {
"type": "docker",
"settings": {
"image": "mcr.microsoft.com/azureiotedge-agent:1.0",
"createOptions": ""
}
},
"edgeHub": {
"type": "docker",
"status": "running",
"restartPolicy": "always",
"settings": {
"image": "mcr.microsoft.com/azureiotedge-hub:1.0",
"createOptions": "{\"HostConfig\":{\"PortBindings\":{\"5671/tcp\":[{\"HostPort\":\"5671\"}], \"8883/tcp\":[{\"HostPort\":\"8883\"}],\"443/tcp\":[{\"HostPort\":\"443\"}]}}}"
}
}
},
"modules": {
"RedisEdge": {
"version": "1.0",
"type": "docker",
"status": "running",
"restartPolicy": "always",
"settings": {
"image": "${MODULES.RedisEdge.amd64}",
"createOptions": "{\"HostConfig\": { \"PortBindings\": { \"6379/tcp\": [ { \"HostPort\": \"6379\" } ] } } }"
}
}
}
}
},
"$edgeHub": {
"properties.desired": {
"schemaVersion": "1.0",
"routes": {},
"storeAndForwardConfiguration": {
"timeToLiveSecs": 7200
}
}
}
}
}
Which results in the following deployment manifest
{
"modulesContent": {
"$edgeAgent": {
"properties.desired": {
"schemaVersion": "1.0",
"runtime": {
"type": "docker",
"settings": {
"minDockerVersion": "v1.25",
"loggingOptions": ""
}
},
"systemModules": {
"edgeAgent": {
"type": "docker",
"settings": {
"image": "mcr.microsoft.com/azureiotedge-agent:1.0",
"createOptions": ""
}
},
"edgeHub": {
"type": "docker",
"status": "running",
"restartPolicy": "always",
"settings": {
"image": "mcr.microsoft.com/azureiotedge-hub:1.0",
"createOptions": "{\"HostConfig\":{\"PortBindings\":{\"5671/tcp\":[{\"HostPort\":\"5671\"}], \"8883/tcp\":[{\"HostPort\":\"8883\"}],\"443/tcp\":[{\"HostPort\":\"443\"}]}}}"
}
}
},
"modules": {
"RedisEdge": {
"version": "1.0",
"type": "docker",
"status": "running",
"restartPolicy": "always",
"settings": {
"image": "andresandboxregistry.azurecr.io/redis-edge:1.0.0-amd64",
"createOptions": "{\"HostConfig\": { \"PortBindings\": { \"6379/tcp\": [ { \"HostPort\": \"6379\" } ] } } }"
}
}
}
}
},
"$edgeHub": {
"properties.desired": {
"schemaVersion": "1.0",
"routes": {},
"storeAndForwardConfiguration": {
"timeToLiveSecs": 7200
}
}
}
}
}