# Implementation Plan: Dataset Lifecycle Workspace

**Branch**: `030-dataset-lifecycle-workspace` | **Date**: 2026-05-19 | **Spec**: [spec.md](./spec.md)
**Input**: Feature specification from `specs/030-dataset-lifecycle-workspace/spec.md`

## Summary

Переработка страницы датасетов (`/datasets`) из табличного вида в полноценное split-view рабочее пространство с: (1) Stats Bar с 4 агрегирующими метриками и серверной фильтрацией через `?filter=`, (2) split-view с карточками датасетов слева и детальной панелью справа, (3) inline-редактированием описаний колонок и метрик через новые superset-tools API эндпоинты, (4) WebSocket-автообновлением при завершении фоновых задач, (5) отображением метрик из Superset API. Изменения затрагивают бэкенд (3 новых DTO, 2 новых эндпоинта, модификация 2 существующих) и фронтенд (5 новых компонентов, переписанный +page.svelte).

## Technical Context

**Language/Version**: Python 3.9+ (backend), JavaScript/TypeScript — Svelte 5 runes (frontend)
**Primary Dependencies**: FastAPI 0.104+, Pydantic v2, SQLAlchemy (backend); SvelteKit 2.x, Svelte 5.x, Vite 7.x, Tailwind CSS 3.x (frontend)
**Storage**: PostgreSQL 16 (superset-tools own DB); no schema changes in this feature
**Testing**: pytest (backend), vitest + @testing-library/svelte 5.x (frontend)
**Target Platform**: Linux server (Docker), modern browsers
**Project Type**: web application (FastAPI REST + WebSocket backend, SvelteKit SPA frontend)
**Performance Goals**: Split-view loading state <100ms; dataset detail content according to API latency; inline-edit save <1s; initial Stats Bar load <200ms (stats computed in-memory from already-loaded full dataset list)
**Constraints**: <400 lines per module (INV_7), RBAC on all new endpoints, Tailwind-only styling, Svelte 5 runes only
**Scale/Scope**: 33 datasets (current), single environment (dev), 5 new frontend components, 2 new API endpoints

## Constitution Check

*GATE: Must pass before Phase 0 research. Re-check after Phase 1 design.*

| Principle | Status | Notes |
|-----------|--------|-------|
| Library-First | ✅ N/A | No new library extracted |
| Semantic Protocol (ADR-0002) | ✅ PASS | All C4/C5 contracts use belief_scope/reason/reflect markers. All components use @UX_STATE. @RATIONALE/@REJECTED on key decisions. |
| Orchestrator Pattern (ADR-0003) | ✅ PASS | Backend proxies Superset API; no direct frontend-to-Superset calls |
| Plugin Architecture (ADR-0004) | ✅ PASS | No new plugin; mapping/docs reuse existing MapperPlugin/DocumentationPlugin |
| Auth RBAC (ADR-0005) | ✅ PASS | New endpoints gated: `has_permission("plugin:migration","READ")` for reads, `has_permission("plugin:migration","WRITE")` for mutations |
| Frontend Svelte 5 Runes (ADR-0006) | ✅ PASS | All components use $state/$derived/$props/$effect |
| Anti-Erosion (INV_7) | ✅ PASS | New components <400 lines each; no monolithic page |

**No blocking conflicts detected.**

## Project Structure

### Documentation (this feature)
```
specs/030-dataset-lifecycle-workspace/
├── plan.md              # This file
├── research.md          # 10 research decisions
├── data-model.md        # Pydantic schemas, frontend types, state machines
├── quickstart.md        # Verification commands
├── contracts/
│   └── modules.md       # 16 contracts with complexity classes
├── spec.md              # Feature specification (7 user stories, 24 FR)
├── ux_reference.md      # UX interaction reference
└── checklists/
    └── requirements.md  # 44 checklist items
```

### Source Code Changes

```text
backend/
├── src/
│   ├── api/routes/
│   │   └── datasets.py           # +MetricItem, +StatsCounts, +2 endpoints, MOD DatasetsResponse
│   └── core/
│       ├── superset_client/
│       │   └── _datasets.py      # MOD get_dataset_detail (metrics extraction)
│       └── task_manager.py       # MOD on_task_complete (WebSocket event)
└── tests/
    └── __tests__/
        └── test_datasets.py      # +tests for new endpoints and metrics

frontend/
├── src/
│   ├── routes/datasets/
│   │   ├── +page.svelte          # REWRITE (split-view orchestrator, ~200 lines)
│   │   ├── StatsBar.svelte       # NEW (4 metric tiles, ~80 lines)
│   │   ├── DatasetList.svelte    # NEW (card grid, pagination, ~250 lines)
│   │   ├── DatasetPreview.svelte # NEW (detail panel, ~150 lines)
│   │   ├── ColumnsTable.svelte   # NEW (inline-edit columns, ~180 lines)
│   │   └── MetricsTable.svelte   # NEW (inline-edit metrics, ~150 lines)
│   └── lib/i18n/locales/
│       ├── en/datasets.json      # +11 keys
│       └── ru/datasets.json      # +11 keys
└── tests/
    └── routes/datasets/
        └── dataset_workspace.test.js  # +component tests for new components
```

## Complexity Tracking

No violations. All components adhere to C1-C5 tier rules per ADR-0002.

| Contract | C | Justification |
|----------|---|--------------|
| MetricItem, StatsCounts, *Update DTOs | 1 | Pure data classes, anchors only |
| DatasetDetailResponse, DatasetsResponse (mod) | 2 | DTOs with @PURPOSE |
| get_dataset_detail (mod), StatsBar, DatasetPreview | 3 | Multi-step logic with @RELATION |
| update_*_description endpoints, get_datasets (mod), DatasetList, ColumnsTable, MetricsTable | 4 | Stateful operations with @PRE/@POST/@SIDE_EFFECT |
| DatasetHub (+page.svelte rewrite) | 5 | Orchestrator with @DATA_CONTRACT, @INVARIANT, decision memory |