ArcGIS Metadata Conversion Tools: Upgrade

The vast majority of the GIS datasets we will be including in the CIC geoportal are described with the FGDC metadata standard. A major goal of this project is to transform this metadata to the ISO standard.

One effective method for achieving this is to first "Upgrade" the FGDC metadata to the ArcGIS 1.0 metadata format. The ArcGIS metadata format can function as a transitional file that will contain everything from the FGDC metadata, and possibly additional technical information. The final step is to transform the ArcGIS metadata format file into one or more ISO XML files.

The ArcGIS 1.0 metadata format file
The ArcGIS 1.0 metadata format was first introduced with Esri's 10.x ArcGIS applications. Previous versions of the software allowed the user to select a metadata style (generally FGDC or ISO) and create metadata XML files to associate with their dataset. Esri refers to this as a "stovepipe" model. ArcGIS stored the technical metadata separately from the standards metadata. In other words, metadata files were distinct from the dataset and the standards were not interchangable.

With ArcGIS 10.x, metadata was more tightly integrated with the data. The new format was introduced that was designed to be a "a standard-neutral format that is a superset of the FGDC and ISO 19115 metadata content standard." The software now creates metadata files by default and includes them with the dataset. This metadata file can then be "filtered" and exported to a standard.

Working with legacy metadata formats
For the CIC project, a large portion of the GIS datasets will have a metadata file that was created prior to ArcGIS 10.x. This file can be transformed into an ArcGIS 1.0 metadata format file with the Upgrade Metadata tool. This tool can be run on a standalone XML file or on with the dataset.

Upgrading a standalone XML file from FGDC to ArcGIS 1.0

This example starts with a standalone XML file in the FGDC format. When opening it in ArcCatalog, a popup box appears that asks if you would like to upgrade the file. Select yes. ArcCatalog will run through a series of scripts that rearranges the elements and deletes empty fields.

Here is a before and after with changes noted:

Before Upgrade	After Upgrade ( parameter 'FGDC_ArcGIS')	Changes
		Title became just "Cemetery" Shapefile was removed - since the XML is standalone, ArcCatalog does not assign a data type to the file.
		A scale range was added. Keywords were transferred  into ISO topic categories is applicable
		A temporal extent was added from date fields Contacts and resource constraints were moved
		Many additional elements from the uneditable portion of the FGDC file were transferred into editable ArcGIS fields.
		The Fields section looks largely the same.
		The metadata format field was changed from ESRI-ISO to ArcGIS 1.0 Modification date remains the same.
		The FGDC Metadata (read-only) is the same.  In this case, the bounding coordinates and the Spatial Reference system did not transfer.

Using the Upgrade tool on a standalone FGDC file does not remove metadata, it just rearranges it. The ArcGIS 1.0 metadata file format is useful in this case because it can be exported to an ISO 19139 metadata file.

To upgrade several XML files at once, I recommend skipping the option of opening the Upgrade tool in batch mode, which is what Esri suggests. This is a tedious process that will occasionally time out. Instead, type the following script into the Python window in ArcCatalog:

import arcpy

from arcpy import env

env.workspace = "add the path to your folder of metadata files here"

for file in arcpy.ListFiles():

       arcpy.UpgradeMetadata_conversion (file, "FGDC_TO_ARCGIS")

Note: this process can be run on a group of shapefiles or feature classes instead of just standalone metadata files. This method has several benefits, including automatic extraction of technical metadata. It will be covered in the upcoming Import Metadata blog post. However, the following batch upgrade script works for a group of datasets:

import arcpy

from arcpy import env

env.workspace = "add the path to your folder of metadata files here"

for fc in arcpy.ListFeatureClasses():

arcpy.UpgradeMetadata_conversion (fc, "FGDC_TO_ARCGIS")