Example deposits workflow

This vignette provides an example of a complete deposits workflow, from initiation of a deposits client through to data publication.

Initial Metadata

As described in the metadata vignette, deposits start with metadata describing general aspects of the data being deposited, such as a title, description, identification of creators, and any other aspects specified in the deposits metadata JSON schema.

This workflow will use the same “beaver” datasets as the metadata vignette, from R’s “datasets” package. That vignette demonstrated how to use the error messages triggered by incorrectly specified metadata to work towards the following, schema-compliant specification:

metadata <- list (
    creator = list (list (name = "P.S. Reynolds")),
    created = "1994-01-01T00:00:00",
    title = "Time-series analyses of beaver body temperatures.",
    description = "Original source of 'beaver' data, in Chapter 11 of  Lange, N., Ryan, L., Billard, L., Brillinger, D., Conquest, L. and Greenhouse, J. eds (1994) Case Studies in Biometry.",
    publisher = "John Wiley and Sons",
    isPartOf = list (list (
        identifier = "ark:/13960/t0mt2n370",
        relation = "isPartOf"
    ))
)

The “isPartOf” element is a key part of “deposits” metadata, enabling individual data sources to be systematically related to other resources, in this case to the book first describing these data which has an associated “ark” identifier. These fields are intended to help linking data depositions with other project outcomes, such as publications, other data sets, or general project descriptions. Fields for these purposes include “hasPart”, “hasVersion”, “isPartOf”, “isReferencedBy”, “isReplacedBy”, “isRequiredBy”, and “isVersionOf”, with details of all fields given in the deposits JSON schema.

Those metadata can then be used to initiate a deposits client with the new() method, demonstrated here with sandbox = TRUE to use the Zenodo “sandbox” environment.

cli <- depositsClient$new (
    service = "zenodo",
    sandbox = TRUE,
    metadata = metadata
)
print (cli)
#> <deposits client>
#> deposits service : zenodo
#>           sandbox: TRUE
#>         url_base : https://sandbox.zenodo.org/api/
#> Current deposits : <none>
#>
#>   hostdata : <none>
#>   metadata : 6 terms (see 'metadata' element for details)

The metadata can be edited and extended as desired. The metadata recorded in the deposits client can be updated after each edit with the deposit_fill_metadata() method:

cli$deposit_fill_metadata (metadata)

While it is always possible to edit deposits metadata directly by passing values to the deposit_fill_metadata() method, the recommended procedure is to generate a “frictionless” metadata file, as described in the vignette of the same name, and to edit the metadata directly in that file. This procedure is demonstrated in the following section. A frictionless metadata file can only be initially generated in response to an actual data resource, and thus the next section begins by generating some example data.

Preparing data sources

The “beaver” data actually comprises two datasets, “beaver1” and “beaver2”, each of which is a time series of body temperature measurements from an individual beaver. For data sources to be uploaded by deposits, they must first exist on a local computer, meaning in this case that copies of these beaver datasets must first be written to local files.

The deposits package presumes that a single deposits lives within a dedicated local directory which includes all associated files. Let’s start by making a temporary directory and storing the “beaver” data there:

beaver_dir <- file.path (tempdir (), "beaver")
if (!dir.exists (beaver_dir)) {
    dir.create (beaver_dir)
}
bv1 <- file.path (beaver_dir, "beaver1.csv")
write.csv (datasets::beaver1, bv1, row.names = FALSE)
bv2 <- file.path (beaver_dir, "beaver2.csv")
write.csv (datasets::beaver1, bv2, row.names = FALSE)

We can then connect the deposits client with that local directory with the deposit_add_resource() method:

cli$deposit_add_resource (beaver_dir)

Printing the client, by typing print(cli), or simply cli, then reveals that it has been connected with the local directory holding those data:

print (cli)
#> <deposits client>
#> deposits service : zenodo
#>           sandbox: TRUE
#>         url_base : https://sandbox.zenodo.org/api/
#> Current deposits : <none>
#>
#>   hostdata : <none>
#>   metadata : 6 terms (see 'metadata' element for details)
#> local_path : /tmp/RtmpPru5st/beaver
#>  resources : 2 local, 0 remote

Frictionless metadata

Calling the deposit_add_resource() method: the first time also writes a “frictionless” metadata file to the local_path directory:

list.files (beaver_dir)
#> [1] "beaver1.csv"      "beaver2.csv"      "datapackage.json"

The additional “datapackage.json” file is initially generated by the “frictionless” R package, which automatically fills out details of each “resource”, or local file, in a “resources” section. The deposits package then inserts the metadata specified above into an additional “metadata” section of the file. The following code illustrates a portion of the contents of that file:

dp <- list.files (beaver_dir, pattern = "datapackage", full.names = TRUE)
readLines (dp) [1:25]
#>  [1] "{"
#>  [2] "  \"profile\": \"tabular-data-package\","
#>  [3] "  \"metadata\": {"
#>  [4] "    \"created\": \"1994-01-01T00:00:00\","
#>  [5] "    \"creator\": ["
#>  [6] "      {"
#>  [7] "        \"name\": \"P.S. Reynolds\""
#>  [8] "      }"
#>  [9] "    ],"
#> [10] "    \"description\": \"Original source of 'beaver' data, in Chapter 11 of  Lange, N., Ryan, L., Billard, L., Brillinger, D., Conquest, L. and Greenhouse, J. eds (1994) Case Studies in Biometry.\","
#> [11] "    \"isPartOf\": ["
#> [12] "      {"
#> [13] "        \"identifier\": \"ark:/13960/t0mt2n370\","
#> [14] "        \"relation\": \"isPartOf\""
#> [15] "      }"
#> [16] "    ],"
#> [17] "    \"publisher\": \"John Wiley and Sons\","
#> [18] "    \"title\": \"Time-series analyses of beaver body temperatures.\""
#> [19] "  },"
#> [20] "  \"resources\": ["
#> [21] "    {"
#> [22] "      \"name\": \"beaver1\","
#> [23] "      \"path\": \"beaver1.csv\","
#> [24] "      \"profile\": \"tabular-data-resource\","
#> [25] "      \"format\": \"csv\","

Once a frictionless “datapackage.json” file has been generated, any subsequent editing of metadata should be done by directly editing that file. Editing should also generally involve extending the automatically-inserted “resource” metadata describing the structure of the actual files, as described in the documentation for the frictionless R package.

Edited and updated versions of metadata can then be loaded into a deposits client by passing the path to the directory as the path argument to the deposit_update() method.

cli$deposit_update (beaver_dir)

Instead of beaver_dir, the full path to the local “datapackage.json” file can also be passed. While the same effect can be achieved by calling the deposit_fill_metadata() method for deposits which have not been initiated on the remote service, the deposit_update() method has additional effects after that point, and is the recommended method once a “datapackage.json” file has been generated. This is demonstrated in the subsequent section.

The following code demonstrates modification and updating of metadata by first modifying the “title”, and then showing that those changes are reflected in the client itself:

m <- readLines (dp)
i <- grep ("\"title\"", m)
m [i] <- gsub ("Time", "Modified time", m [i])
writeLines (m, dp)

cli$metadata$title # original title
#> [1] "Time-series analyses of beaver body temperatures."
cli$deposit_update (beaver_dir)
cli$metadata$title
#> [1] "Modified time-series analyses of beaver body temperatures."

In short, metadata editing with deposits is generally done by editing a local “datapackage.json” file, after which a deposits client can then be updated with the deposit_update() method.

Initiating a remote deposit

The metadata held within a deposits client can be used to initiate a remote deposit on the specified service with the deposit_new() method:

cli$deposit_new ()
#> ID of new deposit : 1065666
print (cli)
#> <deposits client>
#>  deposits service : zenodo
#>            sandbox: TRUE
#>          url_base : https://sandbox.zenodo.org/api/
#>  Current deposits : <none>
#>
#>  url_service : https://sandbox.zenodo.org/deposit/1065666
#>   deposit id : 1065666
#>     hostdata : list with 14  elements
#>     metadata : 7 terms (see 'metadata' element for details)
#>   local_path : /tmp/RtmpMd4uB8/beaver
#>    resources : 2 local, 0 remote

The client now contains additional “hostdata” elements, containing all data recorded by Zenodo for that deposit. The default print method for the client now also lists additional information including a URL for the new deposit, and a unique identifier. In most R environments, the URL can be directly clicked to view the deposit online. All new deposits are private, and can only be viewed after first logging in to the service.

Metadata can still be edited and updated within a client through modifying the “datapackage.json” file. The metadata held on Zenodo can then be updated by calling the deposit_update() method.

Uploading files to a remote deposit

The main purpose of the deposits package, and of online deposition services, is to deposit data. This is done with the deposit_upload_file() method. The main parameter, path, can also be either a single file or an entire directory. If path specifies a directory, all files contained within that directory are uploaded.

cli$deposit_upload_file (beaver_dir)
#> frictionless metadata file has been generated as '/tmp/RtmpCPOaqC/beaver/beaver1.csv'
cli$hostdata$files [, 1:3]

#>                           checksum         filename filesize
#> 1 c8e7ff1e2e4323198b4be5227ff63864      beaver1.csv     1909
#> 2 c8e7ff1e2e4323198b4be5227ff63864      beaver2.csv     1909
#> 3 4fd4b5167c28a874170ab611daf824e7 datapackage.json     1225

The “hostdata” of the client now indicate that the three files have been successfully uploaded.

File compression

The deposit_upload_file() method includes a compress parameter which defaults to "no" for no compression, but can also be set to "tar" or "zip" to compress files prior to uploading. Compression is generally recommended for large files, both to ease uploading and downloading, and to reduce storage sizes on the host services. The frictionless “datapackage.json” file is always stored in uncompressed format, to enable direct inspection via the online platforms. The following code demonstrates the effects of file compression:

cli$deposit_upload_file (beaver_dir, compress = "tar")
#> frictionless metadata file has been generated as '/tmp/RtmpCPOaqC/beaver/beaver1.csv'
cli$hostdata$files [, 1:3]

#>                           checksum         filename filesize
#> 1 03dd72dacab515750494745e17e4f37c   beaver1.tar.gz     3584
#> 2 713ce15cb9d3c2b2b6ba8d541c0934a5   beaver2.tar.gz     3584
#> 3 4fd4b5167c28a874170ab611daf824e7 datapackage.json     1225

The frictionless “datapackage.json” files are never compressed, ensuring that their contents can always be viewed on the web interfaces of the deposits services. (The increase in sizes of the uploaded files there demonstrates that compression often offers little advantage for small files. The advantages for large files can nevertheless be considerable, and compression is generally recommended.)

To change compression, or to compress a file that was previously uploaded in uncompressed form, the file first needs to be removed from the deposits service with the deposit_delete_file() method, and then re-uploaded with either deposit_upload_file() or deposit_update().

Editing and updating files

The deposit_update() method will automatically update any files held on a remote deposits service if they have been locally modified. If the local “datapackage.json” file has been modified, any changes in the “metadata” section will be brought into the local deposits client, and also translated to service-specific metadata, posted to the service, and returned in updated “hostdata” of the client. The remote version of that file will also be updated.

In short, the deposit_upload_file() method is only needed to initially upload files (or directories). Once files exist on the remote deposits service, the deposit_update() method can be used to automatically upload any modified files to the service.

Publishing a deposit

The final steps of publishing a deposit, potentially along with an embargo date, are described in the main vignette, but copied here for completeness.

Once all metadata and data have been satisfactorily edited, updated, and uploaded, a deposit can be made publicly visible and permanently associated a Digital Object Identifier (DOI) by publishing it. Prior to publishing, it is often desired to apply an “embargo” to the deposit, in the form of a date after which the deposit will become publicly visible. The two steps to publication are thus generally:

cli$deposit_embargo (embargo_date = "2030-03-30")
cli$deposit_publish ()

Calling the deposit_publish() method is irreversible, and can never be undone. The published deposit will be permanently associated with the account of the user who published it, as identified by the API token used to initiate the deposits client. Publication will also change many items of the client’s “hostdata”, notably involving a change of status or visibility from “private” to “public”. Once a deposit has been published, the associated DOI, or equivalent the URL given in the deposits client, may be shared as a permanent link to the deposit.

Mark Padgham

2024-12-04