feat: complete catalog-driven preprocessing
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# `.tht-dwh` — DWH generations, `OWNER.json`, ACTIVE, and fingerprints
# Internal Catalog-bound DWH artifacts
> Operator contract. P3 makes the effective DWH/preprocessing configuration reproducible and
> versioned across the operator CLI and the application sessions, and documents what `.tht-dwh`
> is so operators can reason about why a rerun is instant or why it takes minutes.
`.tht-dwh`, `OWNER.json`, and the `ACTIVE` generation pointer are private preprocessing artifacts,
not an operator-facing generation or rollback contract. Complete preprocessing materializes the
physical schema from the immutable PostgreSQL Catalog Metadata Snapshot and samples only eligible
DWH values to build LSH. It never obtains schema metadata from workspace YAML or by introspecting the
DWH in the harness.
## What `.tht-dwh` is
`OWNER.json` binds the artifact root to all of:
`.tht-dwh` is the workspace-local directory that stores the **prepared snapshots of the data
warehouse structure** (the catalog `physical.yaml` plus the LSH hashes used for fuzzy search).
ThothII does not re-read the whole database for every question: it prepares it once, stores the
result here, and reuses it. The directory lives under the workspace runtime root, for example:
- workspace ID;
- Catalog database ID;
- Metadata Content Revision;
- effective configuration fingerprint;
- input fingerprint.
```text
/data/sessions/<workspace-id>/.tht-dwh/
The complete binding must match before artifacts can be reused. This prevents an LSH built from one
database, workspace, Catalog revision, or effective configuration from being associated with
another. PostgreSQL separately owns readiness through `running | succeeded | failed`, the processed
revision, and the preprocessing input fingerprint.
The internal generation is overwritten by normal preprocessing and is not retained for rollback.
Recovery is always:
```sh
tht --installation <absolute>/thothii-installation.yaml \
workspace preprocess run --workspace <workspace-id>
```
## Immutable generations
The clear operation removes `.tht-dwh` together with the LSH, private Catalog snapshot, Evidence
corpus, and derived checkpoints. The next run recreates them from PostgreSQL and the pinned workspace
revision.
Each preparation run produces a **generation**: an immutable directory containing the catalog and
the LSH artifacts for one exact "effective configuration" (see fingerprints below). Generations
are never modified in place; a new run writes a new generation, and an `ACTIVE` pointer selects
which generation the workspace currently uses. Keeping the old generations makes rollback and
diagnosis safe.
## `OWNER.json`
Every generation root contains an `OWNER.json` that records who owns it:
```json
{
"workspace_id": "<workspace-id>",
"config_fingerprint": "sha256:<64 hex>",
"input_fingerprint": "sha256:<64 hex>"
}
```
- `config_fingerprint` is the digest of the **canonical effective configuration** (see below).
- `input_fingerprint` is the digest of the **logical configuration identity**.
Before reusing a generation, the harness compares the current canonical identity with the one in
`OWNER.json`. If they differ, the generation is **refused** (never silently reused) and a new one
is produced. This is what protects ThothII from using artifacts prepared for a different database,
endpoint, user, schema, or index contract.
The reader is compatible with the historical schema-v1 `OWNER.json` (same three keys, `sha256:`
values) so existing installations keep working; new writes use the versioned computation. There is
no automatic in-place reinterpretation: operators regenerate explicitly when a root is old.
## The canonical effective configuration and the logical identity
The **canonical effective configuration** is the non-secret subset of the rendered runtime
configuration that determines whether a prepared DWH generation is still valid:
```json
{
"schemaVersion": 1,
"dwh": {
"engine": "postgres",
"database": "<database>",
"schema": "<schema>",
"transport": "postgres_direct | rest_api | ...",
"host": "<host>",
"port": 5432,
"baseUrl": "<base-url>",
"user": "<user>"
},
"vector": { "collection": "<collection>", "dimensions": 1024, "distance": "cosine" },
"embedding": { "model": "<model>", "dimensions": 1024 },
"roots": { "artifacts": "<abs-path>", "indexes": "<abs-path>" }
}
```
Deliberately **excluded** (their change must not invalidate a DWH generation):
- `session_storage` and `runtime_identity` (a content-only Git commit or an Evidence-only change
must not force a full database re-introspection);
- Evidence source/policy (P6 materialization and Evidence preprocessing are separate);
- memory, search, and execution settings;
- **all credentials** (passwords, API keys, signed URLs, and secret-file paths).
The **logical configuration identity** is:
```text
workspace://<workspace-id>@v1:<sha256 of the canonical effective configuration>
```
It is the same for the operator CLI and for application sessions, because both derive it from the
same rendered configuration. That is the guarantee that the work prepared by `tht` is exactly
what the sessions will consume.
## Why a rerun can be instant or take minutes
- Same canonical identity (e.g., only Evidence files changed) → the generation is reused → the
DWH step is `unchanged` and fast.
- Changed canonical identity (different database, address, user, schema, collection, model, or
artifact/index roots) → the old generation is refused → ThothII re-introspects and writes a new
generation → the step takes as long as the first preparation.
## Safe migration, regeneration, and recovery
- **Migration**: existing schema-v1 `OWNER.json` roots are readable; to switch them to the
versioned identity, run a normal regeneration (explicit `--refresh`/new run). No automatic
in-place rewrite.
- **Regeneration**: a new run produces a new immutable generation and moves `ACTIVE`; the previous
generations remain for rollback.
- **Recovery**: if the active generation is corrupt or owned by another configuration, ThothII
fails closed (never mixes artifacts) and tells the operator to regenerate; the old generations
are still available for inspection.
## Memory root
P3 also gives each workspace an explicit **workspace-global memory root**:
```text
/data/sessions/<workspace-id>/memory/
```
All memory commands, locks, the canonical JSONL registry, and the Qdrant projection use this root
when present. A guarded migration copies and verifies exactly one legacy canonical JSONL from the
old `artifacts/memory` location under the workspace lock and rebuilds the projection; conflicting
legacy registries fail closed. There is no in-place reinterpretation.
## Revision-scoped search records
Schema and Evidence records in the Qdrant collection include the pinned `workspace_revision`, so
searches never mix descriptions or documents from different versions of the workspace. Memory and
solved-question records remain workspace-wide on purpose.
Workspace-global `memory` and Qdrant `solved_question` data are not preprocessing output and remain
preserved both when reference data is overwritten and when preprocessing is cleared.
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When present, `evidence` is strict: it contains `source` and a defaulted strict `policy`; every
source variant and the policy reject unknown keys.
The version numbers are intentionally separate: the Evidence descriptor supports v1/v2, while the
latest Curated Evidence Unit format is v3. There is no Evidence descriptor v3/v4 and no Curated
Evidence Unit v4.
```mermaid
flowchart LR
REGISTRY["Workspace registry"] --> DESCRIPTOR["Evidence descriptor"]
@@ -228,13 +232,15 @@ authoring repository.
P1.1 performs no acquisition, extraction, preprocessing/indexing, embeddings, Qdrant writes,
active-snapshot retention, or GC.
## Operator validation
## Runtime publication
After the runtime configuration is rendered or acquired, validate it with the exact per-command
option ordering:
After the curator has published a valid revision, the installation operator publishes it only as
part of complete workspace preprocessing:
```sh
tht config check -c <path>
tht --installation <absolute>/thothii-installation.yaml \
workspace preprocess run --workspace <workspace-id>
```
Stop after validation. P2/P6 later owns preprocessing and materialization.
This command also consumes the PostgreSQL Catalog snapshot and rebuilds schema/LSH output. There is
no public Evidence-only preprocessing command.
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# Workspace preprocessing CLI contract
`tht` is the only supported host entrypoint for workspace preprocessing.
`tht` exposes one complete, one-shot mutating preprocessing operation. It must succeed before the
workspace can be used by the core.
```mermaid
flowchart LR
OP["Operator"] --> INVOKE["tht workspace preprocess"]
INVOKE --> VALIDATE["Validate descriptor\nand paths"]
VALIDATE --> SOURCE["Read source and\ncurated workspace"]
SOURCE --> NORMALIZE["Normalize and chunk"]
NORMALIZE --> INDEX["Update vector and\nBM25 indexes"]
INDEX --> VERIFY["Verify collection\nand generation"]
VERIFY --> READY["Generation ready"]
VALIDATE -->|"invalid"| STOP["Exit with diagnostic"]
```
## Invocation
## Public commands
```text
tht --installation <absolute>/thothii-installation.yaml workspace inspect
--workspace <id> [--json]
tht --installation <absolute>/thothii-installation.yaml workspace preprocess dwh
--workspace <id> [--resume <32hex>] [--json]
tht --installation <absolute>/thothii-installation.yaml workspace schema suggest-fks
--workspace <id>
[--from-sql <regular-file>]... [--assume <column=table>]...
[--output <new-file>] [--json]
tht --installation <absolute>/thothii-installation.yaml workspace schema check
--workspace <id>
[--annotations <regular-file> --reviewed-candidates <sha256:hex>]
[--json]
tht --installation <absolute>/thothii-installation.yaml workspace schema accept
--workspace <id> --run <32hex> --yes [--json]
tht --installation <absolute>/thothii-installation.yaml workspace index-schema
--workspace <id> [--json]
tht --installation <absolute>/thothii-installation.yaml workspace preprocess evidence
--workspace <id> [--dry-run] [--resume <32hex>] [--json]
tht --installation <absolute>/thothii-installation.yaml workspace preprocess run
--workspace <id> [--resume <32hex>] [--json]
tht --installation <absolute>/thothii-installation.yaml workspace vector inspect
--workspace <id> [--json]
tht --installation <absolute>/thothii-installation.yaml workspace vector rebuild
--workspace <id> --collection <name> --confirm <name> --destroy [--json]
tht --installation <absolute>/thothii-installation.yaml workspace preprocess clear
--workspace <id> [--json]
```
## Qdrant collection lifecycle (P4)
There are no public partial commands for DWH introspection, LSH, FK suggestions, schema indexing,
Evidence indexing, or Qdrant rebuild. `preprocess run` does not accept `--resume`, `--dry-run`, a
generation identifier, or a rollback option. Re-running it replaces the preceding derived output.
`preprocess clear` removes all replaceable preprocessing output and preserves runtime memory.
- `workspace vector inspect` reports the descriptor-owned Qdrant collection contract
(name, dimensions, distance, keyword indexes) **without mutation**.
- `workspace vector rebuild` deletes and recreates the descriptor-owned collection
with the exact contract (1024 dimensions, cosine distance, the 8 required keyword
payload indexes) under guards:
- `--collection <name>` must equal the descriptor's `semantic_index.vector_store.collection`;
- `--confirm <name>` must equal `--collection` (exact repetition);
- `--destroy` is required to confirm the destructive operation;
- the operator refuses any other combination with exit code 2 (usage).
- Self-heal at session admission: a missing collection is created and missing
keyword indexes are added by the shared collection manager; incompatible
dimensions/distance/index types are never mutated (`semantic_index_incompatible`).
- The operator path (`workspace-maintenance.js vector-inspect|vector-rebuild`)
performs the guarded rebuild; rebuild state is written before deletion and the
collection is verified after recreation. No prefix matching or global Qdrant
mutation is performed.
## Sources of truth
## Additive BM25 for Evidence
- The Workspace Descriptor v4 contains workspace identity and optional Evidence configuration.
It contains no database identity, connection, table, column, description, sensitivity, or
relationship data.
- PostgreSQL Metadata Catalog is the sole database authority. It owns the workspace/database
association, installation-local binding, tables, columns, descriptions, sensitivity flags,
physical foreign keys, and active logical relationships.
- The workspace Git revision remains authoritative for Evidence. Evidence Descriptor v1/v2 and
Curated Evidence Unit v3 are unchanged; there is no Evidence v4.
- Only `workspace preprocess evidence` (and the Evidence portion of `workspace preprocess run`)
may add the named sparse vector `bm25` with Qdrant modifier `idf`.
- The upgrade uses Qdrant's additive named-vector operation. It preserves the existing unnamed
dense vector and never deletes, renames, or rebuilds the shared collection.
- Session readiness remains read-only with respect to BM25. Schema, Memory, and solved-question
records therefore continue to use their existing dense-only points during and after an Evidence
upgrade.
- A missing `bm25` is added and reread before Evidence preprocessing starts. An existing definition
other than `modifier: idf` fails as `semantic_index_incompatible` without any collection mutation.
If a later Evidence candidate fails, the compatible additive schema remains in place; it does not
make the dense-only records unavailable.
No metadata is imported from legacy workspace YAML or `physical.yaml`/`annotations.yaml`.
## Preconditions and lock
The maintenance process obtains the PostgreSQL preprocessing lease for the workspace. Acquisition
fails unless:
- the workspace has a Catalog database;
- its latest schema synchronization matches the current database configuration version;
- no catalog sync, description-generation, or sensitivity-analysis run is active;
- no other preprocessing run is active.
While the state is `running`, PostgreSQL rejects database binding changes and every write to the
catalog tables, columns, physical relationships, relationship columns, and logical relationships.
It also rejects the start of the three conflicting background operations. The accepted operating
model assumes no core session is running and nobody attempts core admission during preprocessing;
there is therefore no drain protocol or session pinning.
## Complete pipeline
```mermaid
flowchart LR
CLI["workspace preprocess run"] --> LOCK["Acquire PostgreSQL lease"]
LOCK --> SNAP["Build Catalog Metadata Snapshot"]
SNAP --> LSH["Sample DWH and rebuild LSH"]
SNAP --> SCHEMA["Replace schema vectors"]
SCHEMA --> REL["Index relationships as first-class records"]
LSH --> EVIDENCE["Validate and replace Evidence vectors"]
REL --> EVIDENCE
EVIDENCE --> VERIFY["Verify complete result"]
VERIFY --> READY["Commit succeeded state"]
```
## Curated FK annotations (P5)
The backend reads PostgreSQL and writes one private `Catalog Metadata Snapshot` JSON file. The
Python child receives the snapshot path and the Catalog-derived DWH runtime binding, but never the
Metadata Catalog credentials. It does not query the Catalog.
- The canonical curated annotations file is `<workspace-id>/schema/annotations.yaml`, a regular
Git blob at the same commit as the descriptor. Absence is compatible (empty canonical set +
warning); symlinks, trees/gitlinks, oversized (>16 MiB), non-UTF-8, and malformed objects are
refused at activation.
- Activation synchronizes the blob to the immutable revision-qualified root
`/data/sessions/<id>/revisions/<commit>/artifacts/mschema/annotations.yaml` with a restrictive
mode and an adjacent ownership manifest `{ workspace, commit, blobId, contentDigest,
destination }`. Pinned runtimes resolve annotations from `paths.annotations_root`.
- `workspace schema accept --run <id> --yes` is the only human FK review primitive: after
commit/push/pull, it reads the current synced blob, validates it with the harness parser against
the physical schema and the recorded candidate digest, and records
`{ reviewedCandidatesDigest, annotationsDigest, workspaceRevision, blobId }`. `--yes` is
required; an empty file, an unknown run, a malformed blob, or a non-matching candidate fails
closed without recording a review. `schema check` alone is not evidence of human review.
- `preprocess run` continues only with the exact accepted blob digest and a compatible reusable
DWH binding; otherwise it records a new review checkpoint.
The snapshot contains the complete table and column structure, sensitivity, and effective active
relationships. Effective descriptions use this precedence:
## Commit-addressed Evidence materialization (P6)
1. curated `description`;
2. `generatedDescription`;
3. PostgreSQL `sourceComment`.
- Filesystem Evidence `<workspace-id>/evidence` is materialized from the exact pinned Git commit
into the immutable revision content root `<registry>/snapshots/<commit>/<id>/evidence` at
activation, with a sibling bounded manifest `<id>/evidence.manifest.json` whose digest is chained
into `snapshot.json`.
- Materialization uses fixed Git plumbing (`ls-tree -r -z` + `cat-file blob`) and refuses symlinks
and gitlinks at any depth, traversal/absolute/duplicate/cross-namespace paths, and non-regular
modes. Installation-local limits bound entry count (default 4096), total bytes (64 MiB),
per-file bytes (8 MiB), path bytes (4096), and manifest bytes (1 MiB); a size-sum preflight runs
before any bytes are written and no partial root is published.
- `preprocess evidence` and `preprocess run` operate directly on the materialized root; the
temporary `evidence_materialization_required` stop is retired (the code remains only for
pre-P6 compatibility). For `evidence.schema_version: 2`, runtime acquisition receives exactly
`curated/**/*.md`; `source/` and support files remain in the materialized tree for traceability.
HTTP/S3 Evidence is unchanged.
- The curator validates Evidence before merge. Preprocessing validates the pinned curated corpus
again before it constructs a candidate generation, so an invalid revision is never indexed.
- The runtime writes only its immutable materialized snapshot and derived index state. It never
writes, stages, commits, or pushes the workspace authoring repository.
- Materialized roots are retained with their commit-addressed snapshot directory and removed only
when the revision becomes unreferenced.
The DWH is queried only for derived value samples used by LSH. Sensitive columns are never sampled.
Eligibility is computed deterministically; legacy annotation concepts, synonyms, notes, Evidence
links, and manual eligibility overrides are not part of the snapshot.
## Validation
Qdrant receives first-class `schema_table`, `schema_column`, and `schema_relationship` records. A
relationship search hit promotes both endpoint tables. Each workspace has two physical collections:
- `--installation` is mandatory and absolute.
- `--workspace` is mandatory exactly once and must match `[a-z][a-z0-9-]{2,62}`.
- `--resume` values must be 32 lowercase hex characters.
- `--json` may be supplied once.
- `schema suggest-fks`
- allows at most 32 `--from-sql` files;
- each SQL file must be a canonical regular file, UTF-8, non-symlink, max 1 MiB;
- total SQL ingress must not exceed 16 MiB;
- allows at most 256 `--assume` values, each `column=table`, max 256 bytes;
- `--output` must name a new canonical path; existing targets are refused.
- `schema check`
- `--annotations` and `--reviewed-candidates` are all-or-nothing;
- annotations must be UTF-8, canonical, non-symlink, max 16 MiB;
- `--reviewed-candidates` must match `sha256:<64 lowercase hex>`.
- `schema accept`
- `--run` is mandatory and must be 32 lowercase hex characters;
- `--yes` is mandatory and may be supplied once;
- `--annotations`/`--reviewed-candidates`/`--from-sql`/`--assume` are not accepted.
- Unknown flags, passthrough separators, and shell fragments are rejected before Docker runs.
- `<workspace>-reference` contains `schema_table`, `schema_column`, `schema_relationship`, and
`evidence` records;
- `<workspace>-memory` contains `memory` and `solved_question` records.
A rerun replaces the relevant records in `reference` and leaves `memory` untouched. A workspace
without Evidence is valid and completes with an explicit warning.
The workspace LSH generation is bound to the workspace ID, Catalog database ID, Metadata Content
Revision, effective configuration fingerprint, and input fingerprint. A mismatch cannot reuse a
generation produced for another database or revision.
## Clear lifecycle
`workspace preprocess clear` is intentionally narrower than deleting all semantic data. It:
1. copies any `memory` and `solved_question` records still present in the pre-split workspace
collection to `<workspace>-memory`, then retires that legacy collection (a normal preprocessing
write performs the same one-time cutover if clear was not invoked first);
2. deletes `<workspace>-reference`;
3. removes the active LSH generation, Evidence corpus, private Catalog snapshot, and derived job
checkpoints;
4. records `derived_data_cleared` in PostgreSQL so readiness projects to `required`.
It never deletes `<workspace>-memory`, session artifacts, the workspace repository, Catalog metadata,
or source database data. There is no clear history or rollback. The next complete preprocessing run
recreates the reference collection and all local derived artifacts from their authoritative sources.
## PostgreSQL preprocessing state
PostgreSQL is authoritative for:
- `preprocessing_status`: `running | succeeded | failed`;
- current `metadata_content_revision`;
- last successful `preprocessed_metadata_revision`;
- `preprocessing_input_fingerprint`;
- start/finish timestamps and a bounded failure code.
Every relevant Catalog mutation increments `metadata_content_revision` and marks the prior result
stale in the same transaction. The input fingerprint covers both the immutable workspace Git
revision (including revision-pinned Evidence) and the effective Catalog-derived DWH/semantic
configuration.
Core admission requires all of the following:
- status is `succeeded`;
- processed and current Metadata Content Revision are equal;
- stored and current preprocessing input fingerprints are equal.
Failure leaves the workspace unavailable to the core. There is no rollback: fix the cause and run
the complete command again.
## Administration sidebar
The Administration sidebar exposes the same one-shot operation for the workspace selected in the
composer. It reads `GET /workspaces/:workspaceId/preprocessing`, invokes
`POST /workspaces/:workspaceId/preprocessing` for a run, and invokes
`DELETE /workspaces/:workspaceId/preprocessing` for clear. Both mutations delegate to the complete
workspace preprocessing service and do not expose partial stages.
The compact control has five states: `ready`, `required`, `running`, `blocked`, and `failed`.
**Run again** is available for `ready`, **Run** for `required`, and **Retry** for `failed`. **Clear**
appears to the left of that action whenever replaceable data can be cleared. It opens an inline
confirmation that names both the data removed and the memory retained. All run actions invoke the
same complete, idempotent preprocessing operation. A blocked state
names the current unmet prerequisite and links it to an operator action, but has no run diagnostic
because no preprocessing run started. A failed state shows only the latest bounded diagnostic:
failed stage, safe error code, and finish time. PostgreSQL overwrites that diagnostic when the next
run starts or finishes; there is no preprocessing history or rollback UI. The full service log is
available to operators with `docker compose logs core`.
Once a non-ready state is known, **New session** is disabled. Core admission remains the
authoritative enforcement boundary if the browser has not loaded the state yet.
## Container boundary
`tht` resolves the selected `core` image from the rendered installation, converts it to an immutable local image ID, writes a one-shot final override that pins both `core` and `workspace-maintenance` to that ID with `pull_policy: never`, and runs only:
The host CLI resolves the selected core image to an immutable local image ID and runs only:
```text
docker compose run --rm --no-deps --no-TTY --name <owned-name> workspace-maintenance <fixed-command>
docker compose run --rm --no-deps --no-TTY --name <owned-name> \
workspace-maintenance preprocess-run
docker compose run --rm --no-deps --no-TTY --name <owned-name> \
workspace-maintenance preprocess-clear
```
The request is streamed as one schema-versioned JSON document over stdin. Public stdout is always one schema-versioned JSON result; human mode is rendered from an allowlisted subset of that same result.
The request is one bounded schema-versioned JSON document on stdin. The maintenance process strips
all `THT_CATALOG_*` variables before spawning Python. JSON mode keeps stdout pristine.
## Public JSON result
## Result and exit codes
```json
{
"schemaVersion": 1,
"status": "succeeded|unchanged|dry_run|blocked|failed",
"code": "ok|workspace_not_found|workspace_not_activatable|binding_missing|preprocessing_conflict|preprocessing_resume_mismatch|manual_review_required|evidence_materialization_required|effective_config_mismatch|semantic_index_incompatible|annotation_invalid|egress_policy_refused",
"workspaceId": "abc",
"workspaceRevision": "1234567890abcdef1234567890abcdef12345678",
"descriptorBlob": "sha256:<64 lowercase hex>",
"operation": "inspect|preprocess-dwh|schema-suggest-fks|schema-check|index-schema|preprocess-evidence|preprocess-run",
"runId": "<optional 32hex>",
"childRuns": {"stage": "<optional 32hex>"},
"completedStages": ["stage"],
"counts": {"name": 1},
"artifactIdentities": [{"kind": "fk_candidates", "digest": "sha256:<64 lowercase hex>"}],
"warnings": ["safe warning"]
}
```
The public result includes `schemaVersion`, `status`, `code`, workspace/revision identity,
`operation`, completed stages, safe counts, artifact digests, and the input fingerprint. It never
contains credentials, connection strings, sampled values, SQL, or raw child errors.
`tht --json` parses the operator stdout strictly and re-encodes only the public fields above.
`evidence_materialization_required` is retained for pre-P6 compatibility; since P6, filesystem
Evidence is materialized at activation and preprocesses directly.
## Exit codes
- `0`: `succeeded`, `unchanged`, or `dry_run`
- `3`: `blocked`
- `2`: host-side grammar or local file safety failure
- `1`: operational failure or operator-reported `failed`
- `0`: preprocessing run or clear succeeded;
- `1`: operational or preprocessing failure;
- `2`: invalid host-side invocation.