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Bootstrap

Motivation​

Problem: Applications and their partitions are deployed using cluster app, how to deploy the cluster application itself?

Solution: Bootstrap process. It "deploys" the cluster app and then uses this app to deploy built-in apps.

Technical design​

Overview​

  • Wire service pipeline, provideServicePipeline()
    • "internal services"
    • "admin endpoint", vvm.provideAdminEndpoint()
    • "bootstrap", vvm.provideBootstrapOperator()
      • calls btstrp.Bootstrap(...)
    • "public endpoint"
    • "async actualizers"
  • Start pipeline
  • If DoSync returns error => shutdown

pkg/btstrp.Bootstrap(bus IBus, IAppStructsProvider, appparts, clusterApp ClusterBuiltInApp, otherApps []BuiltInApp) error​

Params​

  • otherApps does NOT include blobber, router

Alg​

  • Deploy cluster app

    • Initialize cluster application workspace, if needed, using IAppStructsProvider
      • All ID must be predefined
    • Create blobber and router storages, if needed
      • Initialize AppStorageBlobber (IAppStorage), AppStorageRouter (IAppStorage)
      • sysmeta storage will be implicitly created, if needed
    • appparts: deploy single clusterApp partition
      • Note for the future: Must be scheduled to the Bootstrap Leader

  • Deploy builtin apps

    • For each app in otherApps
      • c.cluster.DeployApp(app)
        • Use Admin Endpoint to send requests
        • panic if not ok
        • Read/write to the table App + some views

  • Deploy partitions of builtin apps

    • For each app builtInApps
      • appparts: DeployApp
      • appparts: DeployAppPartition

c.cluster.DeployApp(app)​

  • AuthN
    • System
  • Params
    • AppQName
    • AppDeploymentDescriptor // cluster.AppDeploymentDescriptor
  • Flow
    • Idempotent
    • Check application compatibility (409)
    • Create storage if not exists
    • Initialize appstructs data
    • Initialize App Workspaces

apppartsctrl.New(...): Get rid of builtInApps​

  • Get rid of builtInApps

Cluster App Database Schema​

The cluster app uses workspace sys.AppWorkspaceWS and stores this data persistently. During validation, the system reads from this App table to compare the previously deployed NumPartitions with the new deployment request, which is how it detects and prevents partition count changes.

This persistent storage in the cluster app's database is the authoritative source for checking partition counts during subsequent deployments.

pkg/cluster/appws.vsql mode=EXCERPT:

TABLE App INHERITS sys.WDoc (
    AppQName varchar NOT NULL,
    NumPartitions int32 NOT NULL,
    NumAppWorkspaces int32 NOT NULL,
    UNIQUE (AppQName)
);

Deployment Process​

When an app is deployed, the DeployApp command stores the partition information:

pkg/cluster/appws.vsql mode=EXCERPT:

TYPE AppDeploymentDescriptor (
    AppQName varchar NOT NULL,
    NumPartitions int32 NOT NULL,
    NumAppWorkspaces int32 NOT NULL
);

EXTENSION ENGINE BUILTIN (
    COMMAND DeployApp(AppDeploymentDescriptor);
);