aqueduct.resources.mongodb.md

Table of Contents

• aqueduct.resources.mongodb
  • MongoDBCollectionResource
    • find
    • save
  • MongoDBResource
    • collection
    • describe
    • save

aqueduct.resources.mongodb

MongoDBCollectionResource Objects

class MongoDBCollectionResource(BaseResource)

find

@validate_is_connected()
def find(*args: List[Any],
         name: Optional[str] = None,
         output: Optional[str] = None,
         description: str = "",
         parameters: Optional[List[BaseArtifact]] = None,
         lazy: bool = False,
         **kwargs: Dict[str, Any]) -> BaseArtifact

find accepts almost exactly the same input signature as the find exposed by mongo: https://www.mongodb.com/docs/manual/tutorial/query-documents/ .

Under the hood, we call mongo SDK's find API to extract from DB, using arguments you provided to this function.

You can additionally provide the following keyword arguments: name: Name of the query. description: Description of the query. output: Name to assign the output artifact. If not set, the default naming scheme will be used. parameters: An optional list of string parameters to use in the query. We use the Postgres syntax of $1, $2 for placeholders. The number denotes which parameter in the list to use (one-indexed). These parameters feed into the sql query operator and will fill in the placeholders in the query with the actual values.

Example:

country1 = client.create_param("UK", default=" United Kingdom ") country2 = client.create_param("Thailand", default=" Thailand ") mongo_db_resource.collection("hotel_reviews").find( {

• "reviewer_nationality" - {

• "$in" - [$1, $2], } }, parameters=[country1, country2], )

  The query will then be executed with:

• "reviewer_nationality" - {

• "$in" - [" United Kingdom ", " Thailand "], }

  lazy: Whether to run this operator lazily. See https://docs.aqueducthq.com/operators/lazy-vs.-eager-execution .

save

@validate_is_connected()
def save(artifact: BaseArtifact, update_mode: LoadUpdateMode) -> None

Registers a save operator of the given artifact, to be executed when it's computed in a published flow.

Arguments:

artifact: The artifact to save into this collection. update_mode: Defines the semantics of the save if a table already exists. Options are "replace", "append" (row-wise), or "fail" (if table already exists).

MongoDBResource Objects

class MongoDBResource(BaseResource)

Class for MongoDB resource. This works similar to mongo's Database object:

mongo_resource = client.resource("my_resource_name") my_table_artifact = mongo_resource.collection("my_collection").find({})

collection

@validate_is_connected()
def collection(name: str) -> MongoDBCollectionResource

Returns a specific collection object to call .find() method.

Example:

mongo_resource = client.resource("my_resource_name") my_table_artifact = mongo_resource.collection("my_collection").find({})

describe

def describe() -> None

Prints out a human-readable description of the MongoDB resource.

save

@validate_is_connected()
def save(artifact: BaseArtifact, collection: str,
         update_mode: LoadUpdateMode) -> None

Registers a save operator of the given artifact, to be executed when it's computed in a published flow.

Arguments:

artifact: The artifact to save into the given collection. collection: The name of the collection to save to. update_mode: Defines the semantics of the save if a collection already exists. Options are "replace", "append" (row-wise), or "fail" (if table already exists).