dalgo2http

dalgo2http

HTTP/JSON adapter for DALgo: expose read-only REST endpoints (public reference data, internal JSON APIs) as DALgo collections so that the same dal.Query model, and the same access policies, apply to them as to SQL, SQLite, Firestore and inGitDB sources.

Status: bootstrapped 2026-09-09 (founder decision: a generic DALgo adapter for HTTP rather than a consumer-private fetcher). First consumer: DataTug's demo knowledge project (REST Countries, Frankfurter exchange rates).

Design constraints (do not relax without a recorded decision)

• Declarative collections. Each collection is a descriptor: URL template, HTTP method (GET only in v0.x of this adapter), which query fields map to path/query parameters, the JSON path to the rows, the key field, timeout. Descriptors carry no secrets; header values come from the environment.
• Fail closed on pushdown. A dal.Query is executed only when every condition can be expressed by the endpoint (equality on declared parameter fields). Anything else returns a typed "not supported" error. The adapter never fetches a superset and filters client-side unless the descriptor explicitly opts in, because an access-policy predicate that cannot be pushed down must refuse, not leak.
• Declared capabilities. Callers can ask the adapter what it supports per collection so a policy layer can decide before executing.
• Snapshots. An optional recorded snapshot store answers when the endpoint is unreachable; every result says whether it came from live or snapshot.
• Read-only. Writes and transactions that mutate return "not supported".

See spec/ for the Feature and plan once written.