Converting arcpy based python script to OGR for semi-automated Metadata creation

Question

I have created a script to automatically generate base ANZLIC standard metadata using arcpy based coding. Can anyone help me convert it to OGR/GDAL python? This is so that it can be run in QGIS and work with all types of vector and raster data.

The working code with some comments on important sections is below.

import os, xml, arcpy, shutil, datetime
from xml.etree import ElementTree as et

Add/Replace with following

import osgeo, os
from osgeo import ogr

...

Count=0
DECLARATION = """<?xml version="1.0" encoding="utf-8"?>
<?xml-stylesheet type='text/xsl' href='ANZMeta.xsl'?>\n"""

RootDirectory=arcpy.GetParameterAsText(0)
LogDirectory=arcpy.GetParameterAsText(1)
Metadata_Template=arcpy.GetParameterAsText(2)
ANZMeta=arcpy.GetParameterAsText(3)

#RootDirectory=os.getcwd()
#LogDirectory=os.getcwd()

currentPath=RootDirectory
arcpy.env.workspace = RootDirectory
root = Tk()
InputStrings = StringVar()
Entry(root, textvariable=InputStrings).pack()

Generated_XMLs=LogDirectory+'\GeneratedXML_LOG.txt'
f = open(Generated_XMLs, 'a')
f.write("Log of Metadata Creation Process - Update: "+str(datetime.datetime.now())+"\n")
f.close()

for root, dirs, files in os.walk(RootDirectory, topdown=False):
    #print root, dirs
    for directory in dirs:
        try:
            currentPath=os.path.join(root,directory)
        except:
            pass
        os.chdir(currentPath)
        arcpy.env.workspace = currentPath
        print currentPath
#def Create_xml(currentPath):

Here we will need a similar call to list ogr accessible datasets (ogrinfo seems to only list the properties of a file -is there anything similar to arcpy.List...)

        FileList = arcpy.ListFeatureClasses()
        zone="_Zone"

        for File in FileList:
            Count+=1
            FileDesc_obj = arcpy.Describe(File)
            FileNm=FileDesc_obj.file

The code above needs to be a call to osgeo.ogr.Open(File) right?

            check_meta=os.listdir(currentPath)
            existingXML=FileNm[:FileNm.find('.')]
            existingExtension=FileNm[FileNm.find('.'):]
            print "XML: "+existingXML
            #print check_meta
            #if  existingXML+'.xml' in check_meta:
            #newMetaFile='new'
            for f in check_meta:
                if f.startswith(existingXML) and f.endswith('.xml'):
                    print "exists, file name:", f
                    newMetaFile=FileNm+"_2012Metadata.xml"
                    try:
                        shutil.copy2(f, newMetaFile)
                    except:
                        pass
                    break
                else:
                    #print "Does not exist"
                    newMetaFile=FileNm+"_BaseMetadata.xml"

            print "New meta file: "+newMetaFile+ " for: "+File
            if newMetaFile.endswith('_BaseMetadata.xml'):
                    metafile=Metadata_Template
                    shutil.copy2(metafile,newMetaFile)
                    print "copied: "+metafile

            else:
                    shutil.copy2(Metadata_Template, newMetaFile)
                    shutil.copy2(ANZMeta, 'ANZMeta.xsl')


            print "Parsing meta file: "+newMetaFile
            tree=et.parse(newMetaFile)
            print "Processing: "+str(File)


            # Update following info only if no old metadata was found

            # Update all XML files with following data
            for node in tree.findall('.//procstep/srcused'):
                node.text = str(currentPath+"\\"+existingXML+".xml")

            dt=str(datetime.datetime.now())
            for node in tree.findall('.//procstep/date'):
                node.text = str(dt[:10])
            for node in tree.findall('.//procstep/time'):
                node.text = str(dt[11:13]+dt[16:19])
            for node in tree.findall('.//metd/date'):
                node.text = str(dt[:10])

Following needs to be re-written for osgeo...

            for node in tree.findall('.//northbc'):
                node.text = str(FileDesc_obj.extent.YMax)
            for node in tree.findall('.//southbc'):
                node.text = str(FileDesc_obj.extent.YMin)
            for node in tree.findall('.//westbc'):
                node.text = str(FileDesc_obj.extent.XMin)
            for node in tree.findall('.//eastbc'):
                node.text = str(FileDesc_obj.extent.XMax)

            for node in tree.findall('.//nondig/formname'):
                node.text = "File: "+str(os.getcwd()+"\\"+File)

            for node in tree.findall('.//native/digform/formname'):
                node.text = "Type: "+str(FileDesc_obj.featureType)
            for node in tree.findall('.//avlform/nondig/formname'):
                node.text = "Ext: "+str(FileDesc_obj.extension)
            for node in tree.findall('.//avlform/digform/formname'):
                size= str(int(os.path.getsize(currentPath+"\\"+File))/int(1024))+" KB"
                node.text = "Size: "+size
                print size
            for node in tree.findall('.//theme'):
                node.text = str(FileDesc_obj.spatialReference.name +" ; EPSG: "+str(FileDesc_obj.spatialReference.factoryCode))
                print str(FileDesc_obj.spatialReference.name +" ; EPSG: "+str(FileDesc_obj.spatialReference.factoryCode))
            #print node.text
            projection_info=[]
            Zone=FileDesc_obj.spatialReference.name

            if "GCS" in str(FileDesc_obj.spatialReference.name):
                projection_info=[FileDesc_obj.spatialReference.GCSName, FileDesc_obj.spatialReference.angularUnitName, FileDesc_obj.spatialReference.datumName, FileDesc_obj.spatialReference.spheroidName]
                #print "Geographic Coordinate system"
            else:
                projection_info=[FileDesc_obj.spatialReference.datumName, FileDesc_obj.spatialReference.spheroidName, FileDesc_obj.spatialReference.angularUnitName, Zone[Zone.rfind(zone)-3:]]
                #print "Projected Coordinate system"
            x=0
            for node in tree.findall('.//spdom'):
                for node2 in node.findall('.//keyword'):
                    #print node2.text
                    node2.text = str(projection_info[x])
                    #print node2.text
                    x=x+1


            tree.write(newMetaFile)

            # CODE to add declaration back into xml (sometimes required)
##            s = open(currentPath+"\\"+newMetaFile).read()
##            s = s.replace('<anzmeta>', DECLARATION+'<anzmeta>')
##            #s = s.replace('P.O. Box 1616', 'P.O. Box 573')
##            f = open(currentPath+"\\"+newMetaFile, 'w')
##            f.write(s)
##            f.close()

            f = open(Generated_XMLs, 'a')
            f.write(str(Count)+": "+File+"; "+newMetaFile+"; "+currentPath+";"+existingXML+"\n")
            f.close()

I see that there is the following that I can use

dataSource=osgeo.ogr.Open(fn)
layer = dataSource.GetLayer(0)
projection = layer.GetSpatialRef() #Get spatial reference
feature = layer.GetFeature(0)
extent=layer.GetExtent()
numFeatures=layer.GetFeatureCount()