vsi_get_file_metadata: Get metadata on files

In gdalraster: Bindings to the 'Geospatial Data Abstraction Library' Raster API

Get metadata on files

Description

vsi_get_file_metadata() returns metadata for file system objects. Implemented for network-like filesystems. Starting with GDAL 3.7, implemented for /vsizip/ with SOZip metadata. Wrapper of VSIGetFileMetadata() in the GDAL Common Portability Library.

Usage

vsi_get_file_metadata(filename, domain)

Arguments

filename	Character string. The path of the file system object to be queried.
domain	Character string. Metadata domain to query. Depends on the file system, see Details.

Details

The metadata available depends on the file system. The following are supported as of GDAL 3.9:

• HEADERS: to get HTTP headers for network-like filesystems (/vsicurl/, /vsis3/, /vsgis/, etc).

• TAGS: for /vsis3/, to get S3 Object tagging information. For /vsiaz/, to get blob tags.

• STATUS: specific to /vsiadls/: returns all system-defined properties for a path (seems in practice to be a subset of HEADERS).

• ACL: specific to /vsiadls/ and /vsigs/: returns the access control list for a path. For /vsigs/, a single XML=xml_content string is returned.

• METADATA: specific to /vsiaz/: blob metadata (this will be a subset of what domain=HEADERS returns).

• ZIP: specific to /vsizip/: to obtain ZIP specific metadata, in particular if a file is SOZIP-enabled (SOZIP_VALID=YES).

Value

A named list of values, or NULL in case of error or empty list.

See Also

vsi_stat(), addFilesInZip()

Examples

# create an SOZip-enabled file and validate
# Requires GDAL >= 3.7
f <- system.file("extdata/ynp_fires_1984_2022.gpkg", package="gdalraster")

if (as.integer(gdal_version()[2]) >= 3070000) {
  zip_file <- tempfile(fileext=".zip")
  addFilesInZip(zip_file, f, full_paths=FALSE, sozip_enabled="YES")
  zip_vsi <- file.path("/vsizip", zip_file)
  print("Files in zip archive:")
  print(vsi_read_dir(zip_vsi))
  print("SOZip metadata:")
  print(vsi_get_file_metadata(zip_vsi, domain="ZIP"))

  vsi_unlink(zip_file)
}

gdalraster documentation built on April 4, 2025, 4:38 a.m.