アーキテクチャ概要

高レベルアーキテクチャ

Greentic は、責務が明確に分離されたレイヤードアーキテクチャを採用しています:

┌─────────────────────────────────────────────────────────┐
│                    Messaging Channels                    │
│         (Slack, Teams, Telegram, WhatsApp, WebChat)     │
└─────────────────────────────────────────────────────────┘
                            │
                            ▼
┌─────────────────────────────────────────────────────────┐
│                    Gateway (HTTP)                       │
│                 Public Endpoint Router                   │
└─────────────────────────────────────────────────────────┘
                            │
                            ▼
┌─────────────────────────────────────────────────────────┐
│                    greentic-runner                       │
│           (Production Runtime Host)                      │
│  ┌─────────────────────────────────────────────────┐    │
│  │              Flow Executor                       │    │
│  │         (Wasmtime Component Model)              │    │
│  └─────────────────────────────────────────────────┘    │
│  ┌─────────────────────────────────────────────────┐    │
│  │           Session Manager                        │    │
│  │         (Memory / Redis)                         │    │
│  └─────────────────────────────────────────────────┘    │
└─────────────────────────────────────────────────────────┘
                            │
                            ▼
┌─────────────────────────────────────────────────────────┐
│                    WASM Components                       │
│    (Flows, Providers, MCP Tools, Custom Components)     │
└─────────────────────────────────────────────────────────┘

コアコンポーネント

greentic-runner

flow をホストして実行し、session を管理し、platform のすべてのサービスを調整する主要な production runtime です。

greentic-flow

.ygtc ファイル向けの flow schema definition、intermediate representation (IR)、loader、validator です。

greentic-pack

flow、component、asset を含む署名付き .gtpack archive を作成するための pack builder CLI です。

greentic-component

WASM component を構築するための component authoring CLI と runtime utilities です。

Runtime Stack

Layer	Technology	用途
WASM Runtime	Wasmtime v41	Component model の実行
Async Runtime	Tokio v1	Async I/O、task scheduling
HTTP Server	Axum v0.8	REST API、webhook
Message Bus	Internal event bus	event distribution、pub/sub
Session Store	Memory/Redis	flow state の永続化
Secrets	AWS/Azure/GCP/Vault	credential management

データフロー

受信メッセージフロー

1. External Message (e.g., Slack)
   │
2. Webhook Handler (Provider Ingress)
   │
3. Message bus: greentic.messaging.ingress.{env}.{tenant}.{team}.{channel}
   │
4. Flow Router (tenant/team resolution)
   │
5. Flow Executor (WASM component execution)
   │
6. Session State Update
   │
7. Reply/Action Nodes
   │
8. Message bus: greentic.messaging.egress.{env}.{tenant}.{team}.{channel}
   │
9. Provider Egress → External Service

Pack ロードフロー

1. Bundle Configuration (greentic.demo.yaml)
   │
2. Pack Resolver (local/OCI registry)
   │
3. Signature Verification (ed25519-dalek)
   │
4. CBOR Metadata Parsing
   │
5. WASM Component Instantiation
   │
6. WIT Interface Binding
   │
7. Runtime Registration

Multi-Tenancy モデル

Greentic は、あらゆるレイヤーで tenant isolation を実装しています:

Tenant
  └── Environment (prod, staging, dev)
        └── Team
              └── Channel (messaging provider instance)
                    └── Session (user conversation state)

TenantCtx

TenantCtx struct は、すべての操作に渡って流れます:

pub struct TenantCtx {
    pub tenant_id: String,
    pub env_id: String,
    pub team_id: Option<String>,
}

WIT インターフェースアーキテクチャ

Greentic は、component interface を定義するために WebAssembly Interface Types (WIT) specification を使用します:

// greentic-interfaces/wit/greentic/component@0.6.0/package.wit
package greentic:component@0.6.0;

interface control {
  should-cancel: func() -> bool;
  yield-now: func();
}

interface node {
  use greentic:types-core/core@0.6.0.{capability-id, component-id, flow-id, node-error, step-id, tenant-ctx};

  record invocation-envelope {
    ctx: tenant-ctx,
    flow-id: flow-id,
    step-id: step-id,
    component-id: component-id,
    attempt: u32,
    payload-cbor: list<u8>,
    metadata-cbor: option<list<u8>>,
  }

  record invocation-result {
    ok: bool,
    output-cbor: list<u8>,
    output-metadata-cbor: option<list<u8>>,
  }

  variant schema-source {
    cbor-schema-id(string),
    inline-cbor(list<u8>),
    ref-pack-path(string),
    ref-uri(string),
  }

  record io-schema {
    schema: schema-source,
    content-type: string,
    schema-version: option<string>,
  }

  record example {
    title: string,
    input-cbor: list<u8>,
    output-cbor: list<u8>,
  }

  record schema-ref {
    id: string,
    content-type: string,
    blake3-hash: string,
    version: string,
    bytes: option<list<u8>>,
    uri: option<string>,
  }

  record setup-example {
    title: string,
    answers-cbor: list<u8>,
  }

  record setup-template-scaffold {
    template-ref: string,
    output-layout: option<string>,
  }

  variant setup-output {
    config-only,
    template-scaffold(setup-template-scaffold),
  }

  record setup-contract {
    qa-spec: schema-source,
    answers-schema: schema-source,
    examples: list<setup-example>,
    outputs: list<setup-output>,
  }

  record op {
    name: string,
    summary: option<string>,
    input: io-schema,
    output: io-schema,
    examples: list<example>,
  }

  record component-descriptor {
    name: string,
    version: string,
    summary: option<string>,
    capabilities: list<capability-id>,
    ops: list<op>,
    schemas: list<schema-ref>,
    setup: option<setup-contract>,
  }

  describe: func() -> component-descriptor;
  invoke: func(op: string, envelope: invocation-envelope) -> result<invocation-result, node-error>;
}

world component {
  import control;
  export node;
}

サービス依存関係

greentic-types  ─────────────────────────── (foundation)
    ↑
greentic-telemetry
greentic-interfaces ← greentic-types
greentic-config ← greentic-types
    ↑
greentic-session ← greentic-types
greentic-state ← greentic-types + greentic-interfaces
greentic-flow ← greentic-interfaces + greentic-types
    ↑
greentic-pack ← greentic-flow + greentic-types
greentic-component ← greentic-interfaces + greentic-types
greentic-mcp ← greentic-interfaces + greentic-types
    ↑
greentic-runner ← ALL of the above

Observability

Greentic は、分散 tracing と metrics のために OpenTelemetry を使用します:

Tracing: 分散 trace の相関付けを行う OTLP exporter
Metrics: flow execution time、message throughput、error rate
Logging: trace context 付きの structured logging

次のステップ

Flows - flow definition について学ぶ
Packs - pack structure を理解する
Components - カスタム WASM component を構築する