Query and Download Feature Service Attachments — add

Query attachment information using query_layer_attachments() and download attachments using download_attachments().

Feature Services can contain attachments that are associated with a single feature ID.

Use add_features() to add attachments to a feature service
Use update_features() to update the attachments of a feature service
Use query_layer_attachments() to list attachments of a feature service
Use download_attachments() with the results of query_layer_attachments() to download the attachments from a feature service locally

Usage

add_attachments(
  x,
  feature_id,
  path,
  file_name = basename(path),
  .progress = TRUE,
  token = arc_token()
)

query_layer_attachments(
  x,
  definition_expression = "1=1",
  attachments_definition_expression = NULL,
  object_ids = NULL,
  global_ids = NULL,
  attachment_types = NULL,
  keywords = NULL,
  return_metadata = TRUE,
  ...,
  token = arc_token()
)

download_attachments(
  attachments,
  out_dir,
  ...,
  overwrite = FALSE,
  .progress = TRUE,
  token = arc_token()
)

update_attachments(
  x,
  feature_id,
  attachment_id,
  path,
  .progress = TRUE,
  token = arc_token()
)

Arguments

x: an object of class FeatureLayer, Table, or ImageServer.
feature_id: a vector of object IDs that corresponds to the feature of the corresponding attachment_id.
path: a vecetor of the same length as feature_id indicating where the attachment exists.
file_name: the name of the file. Defaults to the basename(path). Must be the same length as feature_id.
.progress: default TRUE. Whether a progress bar should be provided.
token: an httr2_token as created by auth_code() or similar
definition_expression: default 1 = 1. A SQL where clause that is applied to the layer. Only those records that conform to this expression will be returned. This parameter is required if neither object_ids or global_ids have been defined.
attachments_definition_expression: default NULL. A SQL where calsue that is applied to the attachment metadata. only attachments that conform to this expression will be returned.
object_ids: mutually exclusive with definition_expression and global_ids. The object IDs of the features to query attachments of.
global_ids: mutally exclusive with definition_expression and object_ids. The global IDs of the features to query attachments of.
attachment_types: default NULL. A character vector of attachment types to filter on.
keywords: default NULL. A character vector of the keywords to filter on.
return_metadata: default TRUE. Returns metadata stored in the exifInfo field.
...: unused
attachments: a data.frame created by query_layer_attachments(). Must contain the columns name, url, and contentType.
out_dir: the path to the folder to download the file
overwrite: default FALSE. A
attachment_id: the ID of the attachment—this corresponds to the id column returned from query_layer_attachments()

Value

query_layer_attachments() returns a data.frame.

download_attachments() returns a list. If an error occurs, the condition is captured and returned in the list. Otherwise the path to the file that was downloaded is returned.

a data.frame with 2 columns returning the status of the update.

Details

To rename or otherwise modify an attachment in a Feature Service, you must first download that attachment, modify the file on disk, and then upload it again. This is a limitation of ArcGIS Online and Enterprise. If you'd like to see this changed, please submit a community idea at community.esri.com.

If any requests fail, the requests are added as as the errors attribute to the resultant data.frame.

References

See API documentation for more.

ArcGIS REST API Documentation

See API documentation for more.

Examples

if (FALSE) { # \dontrun{
if (interactive()) {
library(arcgisutils)

# authenticate
set_arc_token(auth_user())

# open a feature service
feature_layer <- arc_open("your-item-id") |>
  # layer ID of the feature service
  get_layer(0)

# create a list of features to update
features <- c(1,2,3)

# create a list of files to upload as attachments
attachment_files <- c("path/to/file1.png", "path/to/file2.png", "path/to/file3.png")

# add the attachment files to the features in the feature layer
add_response <- add_attachments(feature_layer, features, attachment_files, use_basename=TRUE)
}
} # }
if (FALSE) { # \dontrun{
# create a url path that isn't too wide for CRAN
furl <- paste(
  c(
    "https://services1.arcgis.com/hLJbHVT9ZrDIzK0I",
    "arcgis/rest/services/v8_Wide_Area_Search_Form_Feature_Layer___a2fe9c",
    "FeatureServer/0"
  ),
  collapse = "/"
)
# connect to the layer
layer <- arc_open(furl)

# get the attachment info
att <- query_layer_attachments(layer)

# download them to a path
download_attachments(att, "layer_attachments")
} # }
if (FALSE) { # \dontrun{
if (interactive()) {
library(arcgisutils)

# authenticate
set_arc_token(auth_user())

# open a feature service
feature_layer <- arc_open("your-item-id") |>
  # layer ID of the feature service
  get_layer(0)

# query attachment layer information
attachments <- query_layer_attachments(feature_layer)

# create a temporary directory
tmp <- tempdir()

# download attachments to the temporary directory
download_attachments(attachments, tmp)

# get original paths
fps <- file.path(tmp, attachments$name)

# prepend attachments with the date
new_filenames <- paste0(Sys.Date(), "-", basename(attachments$name))

# create new file paths
new_fps <- file.path(dirname(fps), new_filenames)

# rename the files
file.rename(fps, new_fps)

# update the attachments
update_res <- update_attachments(
  feature_layer,
  # OID of the feature <> attachment relationship
  attachments$parentObjectId,
  # the attachment ID
  attachments$id,
  # the path to the attachment on disk
  new_fps
)
}
} # }