datapack (version 1.4.1)

initialize,DataObject-method: Initialize a DataObject

Description

When initializing a DataObject using passed in data, one can either pass in the 'id' param as a 'SystemMetadata' object, or as a 'character' string representing the identifier for an object along with parameters for format, user,and associated member node. If 'data' is not missing, the 'data' param holds the 'raw' data. Otherwise, the 'filename' parameter must be provided, and points at a file containing the bytes of the data.

Usage

# S4 method for DataObject
initialize(
  .Object,
  id = NA_character_,
  dataobj = NA,
  format = NA_character_,
  user = NA_character_,
  mnNodeId = NA_character_,
  filename = NA_character_,
  seriesId = NA_character_,
  mediaType = NA_character_,
  mediaTypeProperty = list(),
  dataURL = NA_character_,
  targetPath = NA_character_,
  checksumAlgorithm = "SHA-256"
)

Arguments

.Object

the DataObject instance to be initialized

id

the identifier for the DataObject, unique within its repository. Optionally this can be an existing SystemMetadata object

dataobj

the bytes of the data for this object in 'raw' format, optional if 'filename' is provided

format

the format identifier for the object, e.g."text/csv", "eml://ecoinformatics.org/eml-2.1.1"

user

the identity of the user owning the package, typically in X.509 format

mnNodeId

the node identifier for the repository to which this object belongs.

filename

the filename for the fully qualified path to the data on disk, optional if 'data' is provided

seriesId

A unique string to identifier the latest of multiple revisions of the object.

mediaType

The When specified, indicates the IANA Media Type (aka MIME-Type) of the object. The value should include the media type and subtype (e.g. text/csv).

mediaTypeProperty

A list, indicates IANA Media Type properties to be associated with the parameter "mediaType"

dataURL

A character string containing a URL to remote data (a repository) that this DataObject represents.

targetPath

An optional string that denotes where the file should go in a downloaded package

checksumAlgorithm

A character string specifying the checksum algorithm to use

Details

If filesystem storage is used for the data associated with a DataObject, care must be taken to not modify or remove that file in R or via other facilities while the DataObject exists in the R session. Changes to the object are not detected and will result in unexpected results. Also, if the 'dataobj' parameter is used to specify the data source, then 'filename' argument may also be specified, but in this case the value 'filename' parameter is used to tell DataONE the filename to create when this file is downloaded from a repository.

See Also

DataObject-class

Examples

# NOT RUN {
data <- charToRaw("1,2,3\n4,5,6\n")
do <- new("DataObject", "id1", dataobj=data, "text/csv", 
  "uid=jones,DC=example,DC=com", "urn:node:KNB", targetPath="data/rasters/data.tiff")
# }