ListAzureBlobStorage_v12
Description
Lists blobs in an Azure Blob Storage container. Listing details are attached to an empty FlowFile for use with FetchAzureBlobStorage. This Processor is designed to run on Primary Node only in a cluster. If the primary node changes, the new Primary Node will pick up where the previous node left off without duplicating all of the data. The processor uses Azure Blob Storage client library v12.
Tags
azure, blob, cloud, microsoft, storage
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 |
|---|---|---|---|---|
| Storage Credentials * | storage-credentials-service | Controller Service: AzureStorageCredentialsService_v12 Implementations: AzureStorageCredentialsControllerServiceLookup_v12 AzureStorageCredentialsControllerService_v12 | Controller Service used to obtain Azure Blob Storage Credentials. | |
| Container Name * | container-name | Name of the Azure storage container. In case of PutAzureBlobStorage processor, container can be created if it does not exist. Supports Expression Language, using Environment variables. | ||
| Blob Name Prefix | blob-name-prefix | Search prefix for listing Supports Expression Language, using Environment variables. | ||
| Record Writer | record-writer | Controller Service: RecordSetWriterFactory Implementations: AvroRecordSetWriter CSVRecordSetWriter FreeFormTextRecordSetWriter JsonRecordSetWriter RecordSetWriterLookup ScriptedRecordSetWriter XMLRecordSetWriter | Specifies the Record Writer to use for creating the listing. If not specified, one FlowFile will be created for each entity that is listed. If the Record Writer is specified, all entities will be written to a single FlowFile instead of adding attributes to individual FlowFiles. | |
| Listing Strategy * | listing-strategy | Tracking Timestamps |
| Specify how to determine new/updated entities. See each strategy descriptions for detail. |
| Entity Tracking State Cache | et-state-cache | Controller Service: DistributedMapCacheClient Implementations: HazelcastMapCacheClient MapCacheClientService RedisDistributedMapCacheClientService SimpleRedisDistributedMapCacheClientService | Listed entities are stored in the specified cache storage so that this processor can resume listing across NiFi restart or in case of primary node change. 'Tracking Entities' strategy require tracking information of all listed entities within the last 'Tracking Time Window'. To support large number of entities, the strategy uses DistributedMapCache instead of managed state. Cache key format is 'ListedEntities::{processorId}(::{nodeId})'. If it tracks per node listed entities, then the optional '::{nodeId}' part is added to manage state separately. E.g. cluster wide cache key = 'ListedEntities::8dda2321-0164-1000-50fa-3042fe7d6a7b', per node cache key = 'ListedEntities::8dda2321-0164-1000-50fa-3042fe7d6a7b::nifi-node3' The stored cache content is Gzipped JSON string. The cache key will be deleted when target listing configuration is changed. Used by 'Tracking Entities' strategy. This property is only considered if:
| |
| Entity Tracking Time Window | et-time-window | 3 hours | Specify how long this processor should track already-listed entities. 'Tracking Entities' strategy can pick any entity whose timestamp is inside the specified time window. For example, if set to '30 minutes', any entity having timestamp in recent 30 minutes will be the listing target when this processor runs. A listed entity is considered 'new/updated' and a FlowFile is emitted if one of following condition meets: 1. does not exist in the already-listed entities, 2. has newer timestamp than the cached entity, 3. has different size than the cached entity. If a cached entity's timestamp becomes older than specified time window, that entity will be removed from the cached already-listed entities. Used by 'Tracking Entities' strategy. Supports Expression Language, using Environment variables. This property is only considered if:
| |
| Entity Tracking Initial Listing Target | et-initial-listing-target | All Available |
| Specify how initial listing should be handled. Used by 'Tracking Entities' strategy. This property is only considered if:
|
| Minimum File Age * | Minimum File Age | 0 sec | The minimum age that a file must be in order to be pulled; any file younger than this amount of time (according to last modification date) will be ignored | |
| Maximum File Age | Maximum File Age | The maximum age that a file must be in order to be pulled; any file older than this amount of time (according to last modification date) will be ignored | ||
| Minimum File Size * | Minimum File Size | 0 B | The minimum size that a file must be in order to be pulled | |
| Maximum File Size | Maximum File Size | The maximum size that a file can be in order to be pulled | ||
| Proxy Configuration Service | proxy-configuration-service | Controller Service: ProxyConfigurationService Implementations: StandardProxyConfigurationService | Specifies the Proxy Configuration Controller Service to proxy network requests. Supported proxies: SOCKS, HTTP In case of SOCKS, it is not guaranteed that the selected SOCKS Version will be used by the processor. |
Dynamic Properties
This component does not support dynamic properties.
Relationships
| Name | Description |
|---|---|
| success | All FlowFiles that are received are routed to success |
Reads Attributes
This processor does not read attributes.
Writes Attributes
| Name | Description |
|---|---|
| azure.blobname | The name of the blob on Azure Blob Storage |
| azure.blobtype | Type of the blob (either BlockBlob, PageBlob or AppendBlob) |
| azure.container | The name of the Azure Blob Storage container |
| azure.etag | ETag of the blob |
| azure.length | Length of the blob |
| azure.primaryUri | Primary location of the blob |
| azure.timestamp | Timestamp of the blob |
| lang | Language code for the content |
| mime.type | MIME Type of the content |
State Management
| Scope | Description |
|---|---|
| CLUSTER | After performing a listing of blobs, the timestamp of the newest blob is stored if 'Tracking Timestamps' Listing Strategy is in use (by default). This allows the Processor to list only blobs that have been added or modified after this date the next time that the Processor is run. State is stored across the cluster so that this Processor can be run on Primary Node only and if a new Primary Node is selected, the new node can pick up where the previous node left off, without duplicating the data. |
Restricted
This component is not restricted.
Input Requirement
This component does not allow an incoming relationship.
System Resource Considerations
This component does not specify system resource considerations.
See Also
CopyAzureBlobStorage_v12, DeleteAzureBlobStorage_v12, FetchAzureBlobStorage_v12, PutAzureBlobStorage_v12