Goldpath.FileExchange 0.1.0-preview.8

Goldpath.FileExchange

File-based integration rails as a unit: rails declared as data with baked, compile-checked closures — file-level contracts, idempotent (file, line) ingestion, per-row quarantine that never stops the batch, zero-duplicate replay/reprocess, and archive marks — with the lifecycle published as integration events. Jobs+Bulk cover the pieces; the recurring hand-written glue around them (validate → dedup → quarantine → archive → reprocess) is this module.

builder.AddGoldpathFileExchange(files => files
    .AddRail<RegistryRow>("registry-daily", rail => rail
        .Header(1)
        .ValidateFile(lines => TrailerCountMatches(lines) ? null : "truncated")
        .ParseLine(line => RegistryRow.Parse(line))
        .ValidateRow(row => row.Amount > 0 ? null : "non-positive amount")
        .Handle((row, ct) => ApplyAsync(row, ct))));

• File contract — ValidateFile rejects the WHOLE file (truncation, trailer mismatch); a rejected file ingests nothing and publishes GoldpathFileRejected.
• Idempotent ingestion — the (rail, file, line) key: a re-delivered or replayed file applies zero duplicates.
• Quarantine — a bad row (parse throw, row-contract failure, handler throw) quarantines with its reason; the batch CONTINUES. GoldpathRowsQuarantined fires once per run.
• Reprocess — run the file again: good rows dedup, fixed rows apply and their quarantine records clear.
• Archive mark — every completed run marks the file archived; retention/purge is the Archival module's business.

Progress lives behind IGoldpathFileLedger; the in-memory ledger ships for tests and single-node hosts, a database-backed ledger composes through the seam. Scheduled pick-up and drop ride the Jobs module; transports (SFTP, share, object store) are composed adapters, never rewritten (RFC §1).

Console — MapGoldpathFileExchangeAdmin() mounts the read-only admin surface (/goldpath/admin/fileexchange, contract §7.1: rails with live counts, files newest-first, the quarantine with each row's reason and age) and the operations console federates on it as its seventh module. Behind the ops floor by default; exposeUnsecured: true is the visible opt-out. There are no verbs: re-delivering a file IS the reprocess. The reads need a ledger that implements IGoldpathFileLedgerQueries (both shipped ledgers do).

Boundary with qorpe.sync: Sync migrates and reconciles STORES during a transformation; FileExchange is the PERMANENT integration surface with counterparties (RFC D4).