# paper-doc A tool that supports the paper-writing process: it manages the materials, sections, figures, and references that go into a paper. The name reflects the document-centric core of the workflow — a paper is composed from structured documents rather than written in one pass. The first feature to land is the **template configuration**: a reusable library of section fields plus named templates built from them, so that a paper is written by filling in a known structure instead of deciding one. The second is **paper authoring**: a paper is a document written against a template, sentence by sentence, paragraph by paragraph. The structure is never copied into the paper — it is read from the template on every render — so switching a paper's template re-shapes the whole document in one write without touching a single sentence. ## Tech Stack **Backend** - FastAPI (Python) — REST API - SQLAlchemy + Alembic — ORM layer and schema migrations - TiDB v8.5.0 — MySQL-compatible distributed SQL database, deployed in k3s - Dependencies managed with `venv` + `requirements.txt` **Frontend** - Vue 3 + Vite — single-page application - `axios` — HTTP client - `vue-router` — client-side routing - `pinia` + `pinia-plugin-persistedstate` — state management with persistence - Element Plus — UI component library - Dependencies managed with `pnpm` ## Architecture A decoupled SPA + REST API layout: - The Vue SPA runs in the browser and talks to the backend exclusively over HTTP/JSON via `axios`. It holds no direct database access. - The FastAPI backend owns all persistence. It connects to TiDB through SQLAlchemy sessions and owns the schema through Alembic migrations. - TiDB runs inside the existing k3s cluster. The backend reaches it either through the in-cluster Service (`tidb-tidb.tidb:4000`) or, during local development, through the NodePort `192.168.1.88:32738`. Development runs both parts locally: Vite serves the SPA with a dev proxy that forwards `/api` to the FastAPI process, so the browser sees a single origin and no CORS configuration is required. ``` Browser ──HTTP/JSON──▶ FastAPI ──SQLAlchemy──▶ TiDB (k3s) │ ▲ └── Vite dev server ───┘ (proxy /api) ``` ## Domain Model Six tables, and one rule that the last three follow from. ``` section_field the reusable heading library id, name, level, font_size, font_color paper_template a named outline id, name, abstract template_field the join, and the only home of display order id, template_id → paper_template, field_id → section_field, sort paper the document id, title, template_id, abstract, author, status, keywords, target_journal paper_sentence one sentence, at one position, in one paper id, paper_id → paper, template_id, paper_template_filed_sort, sort, content paper_sentence_reference the citations of one sentence id, sentence_id → paper_sentence, reference_id, quote, sort ``` ### The field library is flat, not a tree `section_field` has no `parent_id`. Hierarchy is expressed only by `level` (1 for `1.`, 2 for `1.1`), which is a *rendering hint*: it drives indentation and numbering semantics in the UI and nothing else. The reason is reuse. With a parent pointer a level-2 heading would belong to exactly one level-1 heading, so "Background" could not sit under both `1. Introduction` and `2. Related Work`. Flat fields are attached to templates, not to each other, so one field can appear in any number of templates, in a different position in each. The numbering a reader sees is part of `name` and is written by the user (`"1. Introduction"`, `"0 Abstract"`). Nothing derives or rewrites it. ### Display order lives in the join table `template_field.sort` is a plain ascending integer and is the **only** thing that decides what order a template's fields appear in. The order the user clicked fields in is never stored, so selecting `字段1, 字段2.1, 字段2, 字段1.1` and setting sorts `1, 4, 3, 2` renders as `字段1, 字段1.1, 字段2, 字段2.1`. Two consequences are deliberate: - **There is no unique constraint on `(template_id, field_id)`.** Placing the same field twice in one template is a legitimate layout — the same level-2 heading under two different level-1 headings. The UI warns about a repeat; it does not forbid one. - **Ties are legal.** Equal `sort` values are broken by insertion order, so the ordering is always total and stable. The UI warns about ties too, and offers a button that renumbers the selection `1..N`. ### Templates hold references, not copies `template_field` points at a library field; it does not snapshot its name or typography. Renaming or restyling a field therefore updates every template that places it, which is what makes "fix the template and the section names follow" work. ### A sentence is addressed by position, not by field id `paper_sentence.paper_template_filed_sort` holds the `sort` of the template placement the sentence belongs to — **not** `template_field.id`, and not `section_field.id`. Together with `sort`, the sentence's own position inside that paragraph, it is everything needed to place a line of text. The indirection is the feature. Two templates have no rows in common, but they can share a position, so a sentence that remembers "I sit at position 7" lands on whatever the new template puts at position 7 when the paper is switched. The alternative — pointing at a placement row — would make every sentence belong to one template and turn a switch into a re-mapping of every line. Three behaviours fall out of that one choice: - **The structure exists before the content.** A paragraph is any position the template defines *or* any position a sentence occupies, so an unwritten paragraph still renders, empty, and a paper created a second ago already has its full shape. - **A switch destroys nothing.** Positions the new template does not define are still rendered, in their place in the order, under the heading 未设定. Switch back and the old headings return, because the sentences never moved. - **Ties and gaps are fine.** Sentences may share a `sort` (broken by `id`) and may be numbered `10, 20, 30` to leave room, exactly as `template_field.sort` allows. The name `paper_template_filed_sort` keeps the spelling the feature was specified with; it is the template field's `sort` (the `sort` column of `template_field`). `paper_sentence.template_id` is the template the sentence was written against. It is kept in step with the paper's current template and is provenance rather than a lookup key: rendering never filters on it, which is precisely why content survives a switch. ### Citations are a table, not a column One sentence may quote several references, so `paper_sentence_reference` holds one row per citation. `quote` — 引用内容 — is required and must not be blank: a citation that does not say what it quotes is rejected with `422` rather than stored as a half-record. `reference_id` is a plain nullable integer with **no** foreign key, because the reference library does not exist yet; a citation may therefore be written now and linked later. ### TiDB does not enforce foreign keys TiDB parses `FOREIGN KEY` for compatibility and then ignores it. The constraints are declared to document the relationships, and the integrity they would provide is enforced in the application layer instead: - deleting a field still placed in a template is refused with `409`, naming the field and how many templates use it; - deleting a template that a paper is written against is refused with `409`, naming the template and how many papers use it — the template is that paper's structure, so removing it would empty the paper rather than tidy up; - creating a template that references a missing field is refused with `400`, and creating or patching a paper that references a missing template likewise; - `PaperTemplate.items`, `Paper.sentences` and `PaperSentence.citations` all use `cascade="all, delete-orphan"`, so deleting a row removes its dependents. ## API All routes are mounted under `/api`. Interactive docs at `/docs`. | Method | Path | Notes | |---|---|---| | `GET` | `/health` | liveness plus a TiDB probe | | `GET` | `/section-fields` | `keyword`, `level`, `page`, `page_size` | | `POST` | `/section-fields` | create | | `GET` `PATCH` `DELETE` | `/section-fields/{id}` | read / partial update / delete | | `POST` | `/section-fields/batch-delete` | body `{ "ids": [...] }` | | `GET` | `/templates` | `keyword` matches name **or** abstract | | `POST` | `/templates` | name + abstract + ordered `fields` | | `GET` `PATCH` `DELETE` | `/templates/{id}` | `PATCH` with `fields` replaces the selection | | `POST` | `/templates/batch-delete` | body `{ "ids": [...] }` | | `GET` | `/papers` | `keyword` matches title/author/keywords, plus `status`, `template_id` | | `POST` | `/papers` | title + template + author/status/keywords/journal; no sentence rows are created | | `GET` `PATCH` `DELETE` | `/papers/{id}` | `PATCH` with `template_id` **is** the template switch | | `POST` | `/papers/batch-delete` | body `{ "ids": [...] }` | | `GET` | `/papers/{id}/document` | the whole paper: paragraphs in order, citations, warnings | | `GET` | `/papers/{id}/paragraphs/{sort}` | one paragraph, assembled as the document renders it | | `PUT` | `/papers/{id}/paragraphs/{sort}` | full replacement; optional `target_sort` moves it | | `POST` | `/papers/{id}/sentences` | append one sentence | | `PATCH` `DELETE` | `/papers/{id}/sentences/{id}` | edit or remove one sentence | Conventions worth knowing: - `font_color` is stored and returned as canonical `#RRGGBB`. The API also accepts `rgb(r, g, b)`, `#rgb` and bare `aabbcc`, and normalises them on write. - `font_size` is a JSON number, not a string — a client should not have to parse it before using it in a CSS rule. - List endpoints return `{ items, total, page, page_size, pages }`. - A template read returns `fields` already ordered by `sort`; clients never sort. - A paper document returns its `paragraphs` in ascending position order, already carrying their sentences and citation numbering. The client sorts nothing and merges nothing: two implementations of the same ordering rule would eventually disagree. - Sentence `content` is folded to a single line (leading, trailing and inner whitespace runs collapse to one space), so an all-whitespace sentence becomes the empty string — legal, and rendered as a blank line. A citation with a blank `quote` is refused with `422`. - `keywords` is stored as a canonical ``, ``-joined string; `，`、`;` and `；` are accepted on write and de-duplicated. - Paper `status` is one of `draft`, `writing`, `done`. ## Frontend ### Shell ``` ┌───────────────────┬──────────────────────────────────────┐ │ [mark] paper-doc │ 论文 模板 [mk] │ header ├───────────────────┼──────────────────────────────────────┤ │ 论文 │ │ second-level │ 论文列表 │ │ menu, left │ 新建论文 │ │ │ ── 我的论文 ── │ │ │ ● 论文标题 A │ │ │ ● 论文标题 B │ │ └───────────────────┴──────────────────────────────────────┘ <- 208px -> ``` The mark appears at both ends of the header. The second-level menu sits on the **left** and is driven by `route.meta.section`, so a route declares which menu it belongs to and deep links render correctly on first paint. Routes without a `section` (the welcome page) show no menu. The 论文 menu is the one that is not a static list: it carries the papers themselves, read from the `papers` store, so a paper can be opened straight from the rail. Every page that creates, renames or deletes a paper reloads that store, which is what keeps the rail and the table showing the same thing. A filter box appears once there are more than six papers. Two things about this layout are deliberate and easy to break by accident: - **Which side the menu lands on follows from its DOM order** inside the flex row in `App.vue` — first child, left. Moving it is a one-block change there, not a stylesheet override. - **The logo block is exactly as wide as the rail.** Both read `asideWidth()` from `src/layout.ts`, so they cannot drift apart, and collapsing the rail narrows the logo block with it (dropping the wordmark and centring the mark). The header's own padding is zeroed for this; the two insets come from `ASIDE_INSET` so the mark lines up with the section title below it. The column also carries through to the content: the rail is 208px and both the top nav's first item and `.el-main` are inset a further 20px by their own Element Plus defaults, so the menu text, the page body, and the page header all start on the same vertical line. ### Shell metrics `src/layout.ts` is the single source for the rail's width and inset. It is a module rather than CSS custom properties because `el-aside` takes its width through a prop, which would otherwise fight an inline style coming from the stylesheet. ### Routes | Path | View | Section | |---|---|---| | `/` | welcome | — | | `/papers` | paper table + CRUD (`?new=1` opens the create dialog) | `papers` | | `/papers/:id` | one paper, read as a document | `papers` | | `/templates` | redirects to `/templates/list` | — | | `/templates/list` | template table + CRUD | `templates` | | `/templates/fields` | field library + CRUD | `templates` | ### The paper view `PapersView` is the library; `papers/PaperDetailView` is the writing surface. The detail view renders the server's document verbatim and adds three things it alone knows how to do: - **an edit button beside every paragraph**, written or not — content only ever enters a paper through the paragraph editor, so it may never be the thing that is missing; - **numbered citation markers** in the text, matching the 参考文献 list, which is numbered in reading order rather than per paragraph; - **a 切换模板 dialog that previews the impact** — how much content lands under a new heading, how much keeps its place under 未设定, and how many empty paragraphs the new template adds — because a switch re-shapes the whole document in one write. Changing a paper's template from the metadata form is deliberately disabled: a silent re-shape of the document is exactly what the preview exists to prevent. ## Directory Structure ``` paper-doc/ ├── backend/ # FastAPI application │ ├── app/ │ │ ├── api/routes/ # route handlers (health, papers, section_fields, templates) │ │ ├── core/ # settings and configuration │ │ ├── crud/ # data-access helpers │ │ ├── db/ # engine, session, declarative base │ │ ├── models/ # SQLAlchemy models │ │ └── schemas/ # Pydantic request/response models │ ├── alembic/ # migration environment and revisions │ ├── scripts/seed.py # idempotent seed for the field library + templates │ ├── scripts/smoke_papers.py # end-to-end check of the writing loop │ ├── alembic.ini │ ├── requirements.txt │ └── .env.example ├── frontend/ # Vue 3 SPA │ ├── src/ │ │ ├── api/ # axios instance and endpoint modules │ │ ├── components/ # shell, field, template and paper components │ │ ├── router/ # vue-router configuration │ │ ├── stores/ # pinia stores (UI prefs persisted, the paper list not) │ │ ├── styles/ # global reset and the shell viewport contract │ │ ├── utils/ # formatting helpers │ │ └── views/ # route-level components (papers/, templates/) │ ├── package.json │ └── vite.config.ts └── docs/ # project documentation └── OVERVIEW.md ``` ## Getting Started **Prerequisites** - Python 3.10+ with `venv` - Node.js 18+ with `pnpm` - Network access to the TiDB instance (local development uses the NodePort) **Backend** ```bash cd backend python3 -m venv .venv && source .venv/bin/activate pip install -r requirements.txt cp .env.example .env # then fill in the database credentials uvicorn app.main:app --reload --port 8000 ``` API docs are then served at . **Frontend** ```bash cd frontend pnpm install pnpm dev ``` The SPA is served at and proxies `/api` to the backend on port 8000. **Database** The `paper_doc` database is created once, out of band, against TiDB. Schema changes are applied through Alembic: ```bash cd backend alembic upgrade head ``` **Seed data** `scripts/seed.py` fills the field library with a standard academic outline (20 fields, from `0 Abstract` to `7 References`) and creates three starter templates. It matches fields and templates by name, so running it twice adds nothing: ```bash cd backend .venv/bin/python scripts/seed.py # add anything missing .venv/bin/python scripts/seed.py --reset # empty the tables first ``` **Checking the paper feature end to end** `scripts/smoke_papers.py` walks the whole writing loop against a running API — create a paper on a template, verify the empty structure, fill a paragraph with sentences and citations, switch the template, check that unmatched positions survive under an unset heading, move a paragraph, and delete it all again. It exits non-zero on the first failed expectation and cleans up after itself: ```bash cd backend .venv/bin/python scripts/smoke_papers.py ```