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PipelineSource

class PipelineSource

Start of a Firestore Pipeline

Summary

Public companion functions
`Pipeline`	`subcollection(path: String)` Initializes a pipeline scoped to a subcollection.
`Pipeline`	`subcollection(source: SubcollectionSource)` Creates a pipeline that processes the documents in the specified subcollection of the current document.

Public functions
`Pipeline`	`collection(path: String)` Set the pipeline's source to the collection specified by the given path.
`Pipeline`	`collection(ref: CollectionReference)` Set the pipeline's source to the collection specified by the given `CollectionReference`.
`Pipeline`	`collection(ref: CollectionReference, options: CollectionSourceOptions)` Set the pipeline's source to the collection specified by the given `CollectionReference`.
`Pipeline`	`collectionGroup(collectionId: String)` Set the pipeline's source to the collection group with the given id.
`Pipeline`	`collectionGroup(collectionId: String, options: CollectionGroupOptions)` Set the pipeline's source to the collection group with the given id.
`Pipeline`	`createFrom(aggregateQuery: AggregateQuery)` Convert the given Aggregate Query into an equivalent Pipeline.
`Pipeline`	`createFrom(query: Query)` Convert the given Query into an equivalent Pipeline.
`Pipeline`	`database()` Set the pipeline's source to be all documents in this database.
`Pipeline`	`documents(vararg documents: DocumentReference)` Set the pipeline's source to the documents specified by the given DocumentReferences.
`Pipeline`	`documents(vararg documents: String)` Set the pipeline's source to the documents specified by the given paths.

Public companion functions

subcollection

fun subcollection(path: String): Pipeline

Initializes a pipeline scoped to a subcollection.

This method allows you to start a new pipeline that operates on a subcollection of the current document. It is intended to be used as a subquery.

Note: A pipeline created with subcollection cannot be executed directly. It must be used within a parent pipeline.

Example:

firestore.pipeline().collection("books")
    .addFields(
        PipelineSource.subcollection("reviews")
            .aggregate(AggregateFunction.average("rating").as("avg_rating"))
            .toScalarExpression().as("average_rating"))

Parameters
`path: String`	The path of the subcollection.

Returns
`Pipeline`	A new `Pipeline` instance scoped to the subcollection.

subcollection

fun subcollection(source: SubcollectionSource): Pipeline

Creates a pipeline that processes the documents in the specified subcollection of the current document.

Example:

firestore.pipeline().collection("books")
    .addFields(
        PipelineSource.subcollection(SubcollectionSource.of("reviews"))
            .aggregate(AggregateFunction.average("rating").as("avg_rating"))
            .toScalarExpression().as("average_rating"))

Parameters
`source: SubcollectionSource`	The subcollection that will be the source of this pipeline.

Returns
`Pipeline`	A new `Pipeline` scoped to the subcollection.

Public functions

collection

fun collection(path: String): Pipeline

Set the pipeline's source to the collection specified by the given path.

Parameters
`path: String`	A path to a collection that will be the source of this pipeline.

Returns
`Pipeline`	A new `Pipeline` object with documents from target collection.

collection

fun collection(ref: CollectionReference): Pipeline

Set the pipeline's source to the collection specified by the given CollectionReference.

Parameters
`ref: CollectionReference`	A `CollectionReference` for a collection that will be the source of this pipeline.

Returns
`Pipeline`	A new `Pipeline` object with documents from target collection.

Throws
`kotlin.IllegalArgumentException: kotlin.IllegalArgumentException`	Thrown if the `ref` provided targets a different project or database than the pipeline.

collection

fun collection(ref: CollectionReference, options: CollectionSourceOptions): Pipeline

Set the pipeline's source to the collection specified by the given CollectionReference.

Parameters
`ref: CollectionReference`	A `CollectionReference` for a collection that will be the source of this pipeline.
`options: CollectionSourceOptions`	`CollectionSourceOptions` for the collection.

Returns
`Pipeline`	A new `Pipeline` object with documents from target collection.

Throws
`kotlin.IllegalArgumentException: kotlin.IllegalArgumentException`	Thrown if the `ref` provided targets a different project or database than the pipeline.

collectionGroup

fun collectionGroup(collectionId: String): Pipeline

Set the pipeline's source to the collection group with the given id.

Parameters
`collectionId: String`	The id of a collection group that will be the source of this pipeline.

Returns
`Pipeline`	A new `Pipeline` object with documents from target collection group.

collectionGroup

fun collectionGroup(collectionId: String, options: CollectionGroupOptions): Pipeline

Set the pipeline's source to the collection group with the given id.

Parameters
`collectionId: String`	The id of a collection group that will be the source of this pipeline.
`options: CollectionGroupOptions`	`CollectionGroupOptions` for the collection group.

Returns
`Pipeline`	A new `Pipeline` object with documents from target collection group.

createFrom

fun createFrom(aggregateQuery: AggregateQuery): Pipeline

Convert the given Aggregate Query into an equivalent Pipeline.

Parameters
`aggregateQuery: AggregateQuery`	An Aggregate Query to be converted into a Pipeline.

Returns
`Pipeline`	A new `Pipeline` object that is equivalent to `aggregateQuery`

Throws
`kotlin.IllegalArgumentException: kotlin.IllegalArgumentException`	Thrown if the `aggregateQuery` provided targets a different project or database than the pipeline.

createFrom

fun createFrom(query: Query): Pipeline

Convert the given Query into an equivalent Pipeline.

Parameters
`query: Query`	A Query to be converted into a Pipeline.

Returns
`Pipeline`	A new `Pipeline` object that is equivalent to `query`

Throws
`kotlin.IllegalArgumentException: kotlin.IllegalArgumentException`	Thrown if the `query` provided targets a different project or database than the pipeline.

database

fun database(): Pipeline

Set the pipeline's source to be all documents in this database.

Returns
`Pipeline`	A new `Pipeline` object with all documents in this database.

documents

fun documents(vararg documents: DocumentReference): Pipeline

Set the pipeline's source to the documents specified by the given DocumentReferences.

Parameters
`vararg documents: DocumentReference`	DocumentReferences specifying the individual documents that will be the source of this pipeline.

Returns
`Pipeline`	Pipeline with `documents`.

Throws
`kotlin.IllegalArgumentException: kotlin.IllegalArgumentException`	Thrown if the `documents` provided targets a different project or database than the pipeline.

documents

fun documents(vararg documents: String): Pipeline

Set the pipeline's source to the documents specified by the given paths.

Parameters
`vararg documents: String`	Paths specifying the individual documents that will be the source of this pipeline.

Returns
`Pipeline`	A new `Pipeline` object with `documents`.