Manage storage in Microsoft's 'Azure' cloud: < https://azure.microsoft.com/services/storage>. On the admin side, 'AzureStor' includes features to create, modify and delete storage accounts. On the client side, it includes an interface to blob storage, file storage, and 'Azure Data Lake Storage Gen2': upload and download files and blobs; list containers and files/blobs; create containers; and so on. Authenticated access to storage is supported, via either a shared access key or a shared access signature (SAS).
This package implements both an admin- and client-side interface to Azure Storage Services. The admin interface uses R6 classes and extends the framework provided by AzureRMR. The client interface provides several S3 methods for efficiently managing storage and performing file transfers.
The interface for accessing storage is similar across blobs, files and ADLSGen2. You call the
storage_endpoint function and provide the endpoint URI, along with your authentication credentials. AzureStor will figure out the type of storage from the URI.
AzureStor supports all the different ways you can authenticate with a storage endpoint:
In the case of an AAD token, you can also provide an object obtained via
AzureAuth::get_azure_token(). If you do this, AzureStor can automatically refresh the token for you when it expires.
# various endpoints for an account: blob, file, ADLS2bl_endp_key <- storage_endpoint("", key="access_key")fl_endp_sas <- storage_endpoint("", sas="my_sas")ad_endp_tok <- storage_endpoint("", token="my_token")# alternative (recommended) way of supplying an AAD tokentoken <- AzureRMR::get_azure_token("",tenant="myaadtenant", app="app_id", password="mypassword"))ad_endp_tok2 <- storage_endpoint("", token=token)
AzureStor provides a rich framework for managing storage. The following generics allow you to manage storage containers:
storage_container: get a storage container (blob container, file share or ADLS filesystem)
# example of working with containers (blob storage)list_storage_containers(bl_endp_key)cont <- storage_container(bl_endp, "mycontainer")newcont <- create_storage_container(bl_endp, "newcontainer")delete_storage_container(newcont)
These functions for working with objects within a storage container:
list_storage_files: list files/blobs in a directory (for ADLSgen2 and file storage) or blob container
create_storage_dir: for ADLSgen2 and file storage, create a directory
delete_storage_dir: for ADLSgen2 and file storage, delete a directory
delete_storage_file: delete a file or blob
storage_download: transfer a file to or from a storage container
storage_multidownload: transfer multiple files in parallel to or from a storage container
# example of working with files and directories (ADLSgen2)cont <- storage_container(ad_end_tok, "myfilesystem")list_storage_files(cont)create_storage_dir(cont, "newdir")storage_download(cont, "/readme.txt", "~/readme.txt")storage_multiupload(cont, "N:/data/*.*", "newdir") # uploading everything in a directory, in parallel
AzureStor includes a number of extra features to make transferring files efficient.
First, as noted above, you can transfer multiple files in parallel using the
multidownload_* functions. These use a pool of background R processes to do the transfers in parallel, which usually results in major speedups when transferring multiple small files. The pool is created the first time a parallel file transfer is performed, and persists for the duration of the R session; this means you don't have to wait for the pool to be (re-)created each time.
# uploading/downloading multiple files at once: use a wildcard to specify files to transfermultiupload_adls_file(filesystem, src="N:/logfiles/*.zip", dest="/")multidownload_adls_file(filesystem, src="/monthly/jan*.*", dest="~/data/january")
Second, you can upload a (single) in-memory R object via a connection, and similarly, you can download a file to a connection, or return it as a raw vector. This lets you transfer an object without having to create a temporary file as an intermediate step.
# uploading serialized R objects via connectionsjson <- jsonlite::toJSON(iris, pretty=TRUE, auto_unbox=TRUE)con <- textConnection(json)upload_blob(cont, src=con, dest="iris.json")rds <- serialize(iris, NULL)con <- rawConnection(rds)upload_blob(cont, src=con, dest="iris.rds")# downloading files into memory: as a raw vector with dest=NULL, and via a connectionrawvec <- download_blob(cont, src="iris.json", dest=NULL)rawToChar(rawvec)con <- rawConnection(raw(0), "r+")download_blob(cont, src="iris.rds", dest=con)unserialize(con)
Third, AzureStor includes an interface to AzCopy, Microsoft's high-performance commandline utility for copying files to and from storage. To take advantage of this, simply include the argument
use_azcopy=TRUE on any upload or download function. AzureStor will then call AzCopy to perform the file transfer, rather than using its own internal code. In addition, a
call_azcopy function is provided to let you use AzCopy for any task.
# use azcopy to downloadmyfs <- storage_container(ad_endp, "myfilesystem")storage_download(adlsfs, "/incoming/bigfile.tar.gz", "/data")# use azcopy to sync a local and remote dircall_azcopy('sync c:/local/path "" --recursive=true')
For more information, see the AzCopy repo on GitHub.
Note that AzureStor uses AzCopy version 10. It is incompatible with versions 8.1 and earlier.
Finally, AzureStor's admin-side interface allows you to easily create and delete resource accounts, as well as obtain access keys and generate a SAS. Here is a sample workflow:
library(AzureRMR)library(AzureStor)# authenticate with Resource Manageraz <- az_rm$new(tenant="myaadtenant.onmicrosoft.com", app="app_id", password="password")sub1 <- az$get_subscription("subscription_id")rg <- sub1$get_resource_group("resgroup")# get an existing storage accountrdevstor1 <- rg$get_storage("rdevstor1")rdevstor1#<Azure resource Microsoft.Storage/storageAccounts/rdevstor1># Account type: Storage# SKU: name=Standard_LRS, tier=Standard# Endpoints:# blob:# queue:# table:# file:# ...# retrieve admin keysrdevstor1$list_keys()# create a shared access signature (SAS)rdevstor1$get_account_sas(permissions="rw")# obtain an endpoint object for accessing storage (will have the access key included by default)rdevstor1$get_blob_endpoint()#Azure blob storage endpoint#URL:#Access key: <hidden>#Azure Active Directory token: <none supplied>#Account shared access signature: <none supplied>#Storage API version: 2018-03-28# create a new storage accountblobstor2 <- rg$create_storage_account("blobstor2", location="australiaeast", kind="BlobStorage")# delete it (will ask for confirmation)blobstor2$delete()
textConnectionobject. For downloading, if
NULL, the downloaded data is returned as a raw vector, or if
rawConnection, in the connection object. See the examples in the documentation.
use_azcopy=TRUEin any upload or download function to call AzCopy rather than relying on internal R code. The
call_azcopyfunction also allows you to run AzCopy with arbitrary arguments. Requires AzCopy version 10.
list_storage_containersfor managing containers (blob containers, file shares, ADLSgen2 filesystems)
storage_multidownloadfor file transfers
delete_storage_filefor managing objects within a container
upload_azure_fileto 4MB, the maximum permitted by the API (#5).