FetchGridFS
Description
Retrieves one or more files from a GridFS bucket by file name or by a user-defined query.
Tags
fetch, gridfs, mongo
Properties
In the list below required Properties are shown with an asterisk (*). Other properties are considered optional. The table also indicates any default values, and whether a property supports the NiFi Expression Language.
| Display Name | API Name | Default Value | Allowable Values | Description |
|---|---|---|---|---|
| Client Service * | gridfs-client-service | Controller Service: MongoDBClientService Implementations: MongoDBControllerService | The MongoDB client service to use for database connections. | |
| Mongo Database Name * | gridfs-database-name | The name of the database to use Supports Expression Language, using FlowFile attributes and Environment variables. | ||
| Bucket Name | gridfs-bucket-name | The GridFS bucket where the files will be stored. If left blank, it will use the default value 'fs' that the MongoDB client driver uses. Supports Expression Language, using FlowFile attributes and Environment variables. | ||
| File Name | gridfs-file-name | The name of the file in the bucket that is the target of this processor. Supports Expression Language, using FlowFile attributes and Environment variables. | ||
| Query | gridfs-query | A valid MongoDB query to use to fetch one or more files from GridFS. Supports Expression Language, using FlowFile attributes and Environment variables. | ||
| Query Output Attribute | mongo-query-attribute | If set, the query will be written to a specified attribute on the output flowfiles. Supports Expression Language, using FlowFile attributes and Environment variables. | ||
| Operation Mode * | mongo-operation-mode | Full Query Fetch |
| This option controls when results are made available to downstream processors. If Stream Query Results is enabled, provenance will not be tracked relative to the input flowfile if an input flowfile is received and starts the query. In Stream Query Results mode errors will be handled by sending a new flowfile with the original content and attributes of the input flowfile to the failure relationship. Streaming should only be used if there is reliable connectivity between MongoDB and NiFi. |
Dynamic Properties
This component does not support dynamic properties.
Relationships
| Name | Description |
|---|---|
| failure | When there is a failure processing the flowfile, it goes to this relationship. |
| original | The original input flowfile goes to this relationship if the query does not cause an error |
| success | When the operation succeeds, the flowfile is sent to this relationship. |
Reads Attributes
This processor does not read attributes.
Writes Attributes
| Name | Description |
|---|---|
| gridfs.file.metadata | The custom metadata stored with a file is attached to this property if it exists. |
State Management
This component does not store state.
Restricted
This component is not restricted.
Input Requirement
This component requires an incoming relationship.
System Resource Considerations
This component does not specify system resource considerations.