Knowledge bases, and a file input that lines up

**Bases.** Documents now live in named collections rather than one flat pile,
and a chat can be pointed at particular ones — "answer from the contracts
folder" is a different question from "answer from everything I have ever
uploaded". A chat with none attached still searches everything its owner can
see, because empty means unscoped, not empty.

The harness names the attached bases. Without that the model cannot tell "there
is nothing about this" from "I am only allowed to see one folder", and it
phrases a miss as the former.

**Sharing moves to the base.** A document is visible to whoever can see the base
it lives in, so `Document` is gone from the shareable types and
`documents.visible()` filters through `base_id`. "This folder is the team's" is
the granularity people think in; per-document grants meant answering "who can
see this?" by checking every file. Moving a document between bases changes who
can see it, so the destination has to be one you own.

`Document.base_id` is nullable only because the column had to be added to a
table that already had rows. `sweep_unfiled()` runs at startup beside the
orphaned-upload sweep and files anything predating bases into its owner's
default, which is what makes "always set" true everywhere else.

**The file input.** `.input` gave it a fixed height and horizontal padding, so
the browser's own button sat hard against the left edge while the filename
floated off the centre line. A file input is two controls in one box and
neither inherits anything useful, so it gets its own rule: no horizontal
padding, the button sized to `--control-h` with the divider that separates it,
and the text centred with line-height rather than flexbox, which file inputs do
not lay out reliably.

437 tests, ruff clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/lembas/api/chats.py

@@ -484,6 +484,26 @@ async def update_chat(request: Request, db: Db, user: RequiredUser, chat_id: str
             )
         chat.system_prompt = str(form["system_prompt"]).strip()[:8000]
 
+    if "knowledge_base_ids" in form:
+        # Sent as a single field even when empty, so that clearing every box
+        # actually clears the attachment -- absent checkboxes carry no signal of
+        # their own, which is the same trap update_chat exists to avoid.
+        from lembas.db.models import KnowledgeBase
+        from lembas.services.library import documents as documents_service
+
+        wanted = [value for value in form.getlist("knowledge_base_ids") if value]
+        chat.knowledge_bases = (
+            list(
+                db.scalars(
+                    documents_service.visible_bases(db, user).where(
+                        KnowledgeBase.id.in_(wanted)
+                    )
+                )
+            )
+            if wanted
+            else []
+        )
+
     submitted_params = {name: form[name] for name in _PARAM_RANGES if name in form}
     if submitted_params:
         if not allowed.get("chat.params"):

src/lembas/api/library.py

@@ -27,6 +27,7 @@ from lembas.db.models import (
     PRINCIPAL_USER,
     Document,
     Group,
+    KnowledgeBase,
     Note,
     Skill,
     SkillRevision,
@@ -92,33 +93,54 @@ async def library_home(user: RequiredUser):
 
 
 # --- Knowledge ---------------------------------------------------------------
+# Route order matters: /library/knowledge/document/{id} must be registered
+# before /library/knowledge/{base_id}, or "document" is parsed as a base id.
+# FastAPI matches in registration order and this has bitten before.
 @router.get("/library/knowledge")
-async def knowledge_list(
-    request: Request, db: Db, user: RequiredUser, q: str = "", page: int = 1, saved: str = ""
-):
-    if q.strip():
-        # Search returns best-match order and its own limit, so it is not paged.
-        rows = documents_service.search(db, user, q, limit=PAGE_SIZE)
-        pager = {"page": 1, "pages": 1, "total": len(rows)}
-    else:
-        rows, pager = _page(
-            db, documents_service.visible(db, user).order_by(Document.created_at.desc()), page
+async def knowledge_list(request: Request, db: Db, user: RequiredUser, error: str = ""):
+    """The bases, not the documents. A library is a set of places first."""
+    bases = list(db.scalars(documents_service.visible_bases(db, user).order_by(KnowledgeBase.name)))
+    counts = {
+        base.id: db.scalar(
+            select(func.count()).select_from(Document).where(Document.base_id == base.id)
         )
+        or 0
+        for base in bases
+    }
     return render(
         request,
         "library/knowledge.html",
         {
             "section": "knowledge",
-            "documents": rows,
-            "q": q,
-            "pager": pager,
-            "saved": saved,
+            "bases": bases,
+            "counts": counts,
+            "error": error,
             **sidebar_context(db, user),
         },
     )
 
 
-@router.get("/library/knowledge/{document_id}")
+@router.post("/api/library/bases")
+async def create_base(
+    db: Db, user: RequiredUser, name: str = Form(""), description: str = Form("")
+) -> Response:
+    try:
+        base = documents_service.create_base(
+            db, owner=user, name=name, description=description
+        )
+    except ValueError as exc:
+        from urllib.parse import quote
+
+        return RedirectResponse(
+            f"/library/knowledge?error={quote(str(exc))}",
+            status_code=status.HTTP_303_SEE_OTHER,
+        )
+    return RedirectResponse(
+        f"/library/knowledge/{base.id}", status_code=status.HTTP_303_SEE_OTHER
+    )
+
+
+@router.get("/library/knowledge/document/{document_id}")
 async def knowledge_detail(request: Request, db: Db, user: RequiredUser, document_id: str):
     document = documents_service.get(db, document_id, user)
     if document is None:
@@ -129,38 +151,129 @@ async def knowledge_detail(request: Request, db: Db, user: RequiredUser, documen
         {
             "section": "knowledge",
             "document": document,
-            **_shared_context(db, user, document),
+            "is_owner": sharing.can_write(document, user),
+            # Only bases this person owns: moving a document into one they can
+            # merely read would hand it to that base's owner.
+            "user_bases": list(
+                db.scalars(
+                    select(KnowledgeBase)
+                    .where(KnowledgeBase.owner_id == user.id)
+                    .order_by(KnowledgeBase.name)
+                )
+            ),
             **sidebar_context(db, user),
         },
     )
 
 
+@router.get("/library/knowledge/{base_id}")
+async def base_detail(
+    request: Request, db: Db, user: RequiredUser, base_id: str, q: str = "", page: int = 1
+):
+    base = documents_service.get_base(db, base_id, user)
+    if base is None:
+        raise HTTPException(status.HTTP_404_NOT_FOUND, "That knowledge base is not available.")
+
+    if q.strip():
+        rows = documents_service.search(db, user, q, limit=PAGE_SIZE, base_ids=[base.id])
+        pager = {"page": 1, "pages": 1, "total": len(rows)}
+    else:
+        rows, pager = _page(
+            db,
+            documents_service.visible(db, user, base_ids=[base.id]).order_by(
+                Document.created_at.desc()
+            ),
+            page,
+        )
+    return render(
+        request,
+        "library/base_detail.html",
+        {
+            "section": "knowledge",
+            "base": base,
+            "documents": rows,
+            "q": q,
+            "pager": pager,
+            **_shared_context(db, user, base),
+            **sidebar_context(db, user),
+        },
+    )
+
+
+@router.post("/api/library/bases/{base_id}")
+async def update_base(request: Request, db: Db, user: RequiredUser, base_id: str) -> Response:
+    base = documents_service.get_base(db, base_id, user)
+    if base is None:
+        raise HTTPException(status.HTTP_404_NOT_FOUND, "That knowledge base is not available.")
+    if not sharing.can_write(base, user):
+        raise HTTPException(status.HTTP_403_FORBIDDEN, "That base is not yours to change.")
+
+    form = await request.form()
+    name = " ".join(str(form.get("name", "")).split())[:200]
+    if name:
+        base.name = name
+    base.description = str(form.get("description", "")).strip()[:2000]
+    db.commit()
+    _apply_shares(db, user, base, form)
+    return RedirectResponse(
+        f"/library/knowledge/{base.id}", status_code=status.HTTP_303_SEE_OTHER
+    )
+
+
+@router.post("/api/library/bases/{base_id}/delete")
+async def delete_base(db: Db, user: RequiredUser, base_id: str) -> Response:
+    base = documents_service.get_base(db, base_id, user)
+    if base is None or not sharing.can_write(base, user):
+        raise HTTPException(status.HTTP_404_NOT_FOUND, "That knowledge base is not available.")
+    documents_service.delete_base(db, base)
+    return RedirectResponse("/library/knowledge", status_code=status.HTTP_303_SEE_OTHER)
+
+
 @router.post("/api/library/documents")
 async def upload_document(
-    db: Db, user: RequiredUser, file: UploadFile = File(...), title: str = Form("")
+    db: Db,
+    user: RequiredUser,
+    file: UploadFile = File(...),
+    title: str = Form(""),
+    base_id: str = Form(""),
 ) -> Response:
+    base = documents_service.get_base(db, base_id, user) if base_id else None
+    if base is not None and not sharing.can_write(base, user):
+        raise HTTPException(status.HTTP_403_FORBIDDEN, "That base is not yours to add to.")
+
     payload = await file.read(files_service.MAX_UPLOAD_BYTES + 1)
     try:
         document = documents_service.store_upload(
-            db, owner=user, payload=payload, filename=file.filename or "file", title=title
+            db,
+            owner=user,
+            payload=payload,
+            filename=file.filename or "file",
+            title=title,
+            base=base,
         )
     except files_service.FileError as exc:
         raise HTTPException(status.HTTP_400_BAD_REQUEST, str(exc)) from exc
     return RedirectResponse(
-        f"/library/knowledge/{document.id}", status_code=status.HTTP_303_SEE_OTHER
+        f"/library/knowledge/{document.base_id}", status_code=status.HTTP_303_SEE_OTHER
     )
 
 
 @router.post("/api/library/documents/link")
-async def save_link(db: Db, user: RequiredUser, url: str = Form(...)) -> Response:
+async def save_link(
+    db: Db, user: RequiredUser, url: str = Form(...), base_id: str = Form("")
+) -> Response:
+    base = documents_service.get_base(db, base_id, user) if base_id else None
+    if base is not None and not sharing.can_write(base, user):
+        raise HTTPException(status.HTTP_403_FORBIDDEN, "That base is not yours to add to.")
+
     config = settings_store.search(db)
     try:
         page = await fetch(url, allow_private=bool(config.get("allow_private_fetch")))
     except FetchError as exc:
         raise HTTPException(status.HTTP_400_BAD_REQUEST, exc.message) from exc
-    document = documents_service.store_page(db, owner=user, page=page)
+    document = documents_service.store_page(db, owner=user, page=page, base=base)
     return RedirectResponse(
-        f"/library/knowledge/{document.id}", status_code=status.HTTP_303_SEE_OTHER
+        f"/library/knowledge/{document.base_id}", status_code=status.HTTP_303_SEE_OTHER
     )
 
 
@@ -177,10 +290,18 @@ async def update_document(
     form = await request.form()
     document.title = str(form.get("title", document.title)).strip()[:300] or document.title
     document.description = str(form.get("description", "")).strip()[:2000]
+
+    # Moving between bases changes who can see it, which is the whole point of
+    # bases -- so the destination has to be one this person can write to.
+    wanted = str(form.get("base_id", "")).strip()
+    if wanted and wanted != document.base_id:
+        destination = documents_service.get_base(db, wanted, user)
+        if destination is not None and sharing.can_write(destination, user):
+            document.base_id = destination.id
+
     db.commit()
-    _apply_shares(db, user, document, form)
     return RedirectResponse(
-        f"/library/knowledge/{document.id}", status_code=status.HTTP_303_SEE_OTHER
+        f"/library/knowledge/document/{document.id}", status_code=status.HTTP_303_SEE_OTHER
     )
 
 
@@ -189,8 +310,11 @@ async def delete_document(db: Db, user: RequiredUser, document_id: str) -> Respo
     document = documents_service.get(db, document_id, user)
     if document is None or not sharing.can_write(document, user):
         raise HTTPException(status.HTTP_404_NOT_FOUND, "That document is not available.")
+    base_id = document.base_id
     documents_service.delete(db, document)
-    return RedirectResponse("/library/knowledge", status_code=status.HTTP_303_SEE_OTHER)
+    return RedirectResponse(
+        f"/library/knowledge/{base_id}", status_code=status.HTTP_303_SEE_OTHER
+    )
 
 
 @router.get("/api/library/documents/{document_id}/content")

src/lembas/api/pages.py

@@ -8,11 +8,12 @@ from sqlalchemy import select
 from sqlalchemy.orm import Session as DBSession
 
 from lembas.api.deps import Db, RequiredUser
-from lembas.db.models import Chat, Folder, Message, User
+from lembas.db.models import Chat, Folder, KnowledgeBase, Message, User
 from lembas.security import permissions
 from lembas.services import audio as audio_service
 from lembas.services import chat as chat_service
 from lembas.services import settings_store
+from lembas.services.library import documents as documents_service
 from lembas.services.markdown import render_markdown
 from lembas.web.templating import STATIC_DIR, render
 
@@ -42,6 +43,19 @@ def _chat_context(db: DBSession, user: User, chat: Chat | None) -> dict:
         # may not be the model the chat is set to now. Keyed by model_id, the
         # denormalised value stored on each message.
         "models_by_id": {m.model_id: m for m in models},
+        # Offered in the chat settings panel so a conversation can be pointed at
+        # particular bases. Empty when the reader has none, and the panel then
+        # shows nothing rather than an empty control.
+        "knowledge_bases": (
+            list(
+                db.scalars(
+                    documents_service.visible_bases(db, user).order_by(KnowledgeBase.name)
+                )
+            )
+            if permissions.has(db, user, "library.use")
+            else []
+        ),
+        "attached_base_ids": [base.id for base in chat.knowledge_bases] if chat else [],
         **audio_service.template_flags(db, user),
     }
 
@@ -223,8 +237,6 @@ async def chat_detail(request: Request, db: Db, user: RequiredUser, chat_id: str
     if current is not None and (current.system_prompt or "").strip():
         inherited, inherited_from = current.system_prompt.strip(), "model"
     else:
-        from lembas.services import settings_store
-
         instance_prompt = (settings_store.get(db, "system_prompt") or "").strip()
         if instance_prompt:
             inherited, inherited_from = instance_prompt, "instance"