Struct MongoSource 

pub struct MongoSource { /* private fields */ }

MongoDB source over a MongoSession, carrying the resolved source.mongo: read options export applies.

Implementations

impl MongoSource

pub fn connect( url: &str, tls: Option<&TlsConfig>, cfg: Option<&MongoConfig>, ) -> Result<Self>

Connect, resolving the optional source.mongo: read options (absent ⇒ relaxed JSON, server read concern, cursor kept alive). Used by create_source (with the config block) and the doctor / type-report probes (with None).

pub fn with_id_range(self, lo: Bson, hi: Bson) -> Self

Bind this reader to one disjoint _id slice [lo, hi) (a parallel worker). Consuming builder — each worker owns its own MongoSource.

pub fn sample_id_ranges( &self, collection: &str, n: usize, ) -> Result<Vec<(Bson, Bson)>>

Split the collection’s _id space into n disjoint, size-balanced ranges [lo, hi) whose union tiles the whole BSON key space (so the union read is the complete collection, no overlap) — for ANY _id type, not just ObjectId. Boundaries come from a $sample of the _ids (a WiredTiger random cursor — O(sample), NOT a collection scan, unlike $bucketAuto which examines every doc), then the N−1 quantiles of the sorted sample. Outer bounds are MinKey/MaxKey, which sort before/after every value, so the first/last range cannot miss the true extremes.

Trait Implementations

impl Source for MongoSource

fn type_mappings( &mut self, _query: &str, _column_overrides: &ColumnOverrides, ) -> Result<Vec<TypeMapping>>

The JSON-blob model has a fixed two-column schema regardless of the query, so check --type-report shows it without touching the server.

fn query_scalar(&mut self, sql: &str) -> Result<Option<String>>

The only scalar rivet asks a mode: full source is the reconcile row count — SELECT COUNT(*) FROM (SELECT * FROM <coll>) AS _rivet_reconcile. Recognize that shape and answer it with countDocuments so rivet run --reconcile verifies Mongo exports like the SQL engines. Any other SQL scalar (cursor MIN/MAX, etc.) has no Mongo meaning → None, which callers treat as “unavailable” and skip.

fn export( &mut self, request: &ExportRequest<'_>, sink: &mut dyn BatchSink, ) -> Result<()>

Execute request.query and stream batches into sink.

fn sample_pressure(&mut self) -> Option<u64>

Sample a monotonic source-pressure counter for the OPT-2 concurrency governor (pipeline::chunked::exec).