mongodb: add importer/exporter integration

[Abdul-Moiz31]

New integration for MongoDB: back up a single logical database via mongodump/mongorestore --archive and restore it to any MongoDB server. Everything lives under mongodb/, in the same family as the existing postgresql and mysql connectors.

Discussed with @Mathieu-PLKR over Discord — scope (logical dump/restore only, mongodb:// URI scheme) confirmed before implementation.

What it does

• Importer (mongodb://[user:pass@]host[:port]/database): wraps mongodump --archive, streamed directly as a single record (/dump.archive) rather than written to a temp file first, plus a lightweight /manifest.json (host, port, database, mongodump version — no live server introspection in v1).
• Exporter: wraps mongorestore --archive, reading straight from the record's io.Reader. Supports drop (maps to mongorestore --drop) as the closest equivalent to Postgres's clean option.
• Importer/exporter only — no storage connector, since MongoDB isn't a spot to durably store Kloset's own chunks (same reasoning as postgresql/mysql).

Options

Connection: location (mongodb:// URI) or standalone host/port/username/password/database overrides, same override pattern as postgresql's schema. tls / tls_ca_file for TLS. mongo_bin_dir to point at a non-$PATH install of the MongoDB database tools. A database (via location path or database key) is required in v1 — enforced both in the JSON schema (anyOf: [location, database]) and at runtime.

Credentials are never placed on the mongodump/mongorestore command line — the connection URI (including password) is written to a 0600 temp --config YAML file instead, mirroring how postgresql injects PGPASSWORD via env and mysql uses --defaults-extra-file.

Explicitly out of scope for v1

--nsInclude/--nsExclude collection filtering, oplog/point-in-time restore, sharded-cluster flags, Atlas-specific auth, mongodb+srv:// (all noted as fast-follows, not blockers).

Validation

• go build ./..., go vet ./..., go mod tidy — clean
• make build — both mongodbImporter and mongodbExporter build successfully
• Testcontainers e2e test (tests/logical/single_test.go) run against live Docker: seeds a mongo:7 source, backs it up via mongodb://.../testdb, verifies the snapshot contains /dump.archive + /manifest.json, restores into a fresh mongo:7 target, and confirms the document count matches — full roundtrip passes.

[Abdul-Moiz31]

Hi @mathieu-plak

Following up on the MongoDB integration we discussed over Discord.

This PR implements the scope you approved: single-database logical backup/restore via mongodump/mongorestore --archive, mongodb:// URI scheme, no oplog/sharded-cluster/Atlas support in v1.

Ran the full test suite locally, including the testcontainers e2e roundtrip against real MongoDB containers , passes end to end.

Happy to adjust anything that doesn't match what you had in mind for v1.

Looking forward !!