How to use ogr - 10 common examples

print("  ->  " + ogr.GetDriver(iDriver).GetName())

        return False

#/* -------------------------------------------------------------------- */
#/*      Try opening the output datasource as an existing, writable      */
#/* -------------------------------------------------------------------- */
    poODS = None
    poDriver = None

    if bUpdate:
        poODS = ogr.Open(pszDestDataSource, True)
        if poODS is None:

            if bOverwrite or bAppend:
                poODS = ogr.Open(pszDestDataSource, False)
                if poODS is None:
                    # /* ok the datasource doesn't exist at all */
                    bUpdate = False
                else:
                    poODS.delete()
                    poODS = None

            if bUpdate:
                print("FAILURE:\n" + 
                        "Unable to open existing output datasource `%s'." % pszDestDataSource)
                return False

        elif len(papszDSCO) > 0:
            print("WARNING: Datasource creation options ignored since an existing datasource\n" + \
                    "         being updated.")

elif poOutputSRS is not None:
                    poDstGeometry.AssignSpatialReference(poOutputSRS)

                if poClipDst is not None:
                    poClipped = poDstGeometry.Intersection(poClipDst)
                    if poClipped is None or poClipped.IsEmpty():
                        continue

                    poDstFeature.SetGeometryDirectly(poClipped)
                    poDstGeometry = poClipped

                if bForceToPolygon:
                    poDstFeature.SetGeometryDirectly(ogr.ForceToPolygon(poDstGeometry))

                elif bForceToMultiPolygon or \
                        (bPromoteToMulti and wkbFlatten(poDstGeometry.GetGeometryType()) == ogr.wkbPolygon):
                    poDstFeature.SetGeometryDirectly(ogr.ForceToMultiPolygon(poDstGeometry))

                elif bForceToMultiLineString or \
                        (bPromoteToMulti and wkbFlatten(poDstGeometry.GetGeometryType()) == ogr.wkbLineString):
                    poDstFeature.SetGeometryDirectly(ogr.ForceToMultiLineString(poDstGeometry))

            gdal.ErrorReset()
            if poDstLayer.CreateFeature( poDstFeature ) != 0 and not bSkipFailures:
                if nGroupTransactions > 0:
                    poDstLayer.RollbackTransaction()

                return False

        #/* Report progress */
        nCount = nCount  + 1
        if pfnProgress is not None:

poDstLayer = None

#/* -------------------------------------------------------------------- */
#/*      If the layer does not exist, then create it.                    */
#/* -------------------------------------------------------------------- */
    if poDstLayer is None:
        if eGType == -2:
            eGType = poSrcFDefn.GetGeomType()

            if bExplodeCollections:
                n25DBit = eGType & ogr.wkb25DBit
                if wkbFlatten(eGType) == ogr.wkbMultiPoint:
                    eGType = ogr.wkbPoint | n25DBit
                elif wkbFlatten(eGType) == ogr.wkbMultiLineString:
                    eGType = ogr.wkbLineString | n25DBit
                elif wkbFlatten(eGType) == ogr.wkbMultiPolygon:
                    eGType = ogr.wkbPolygon | n25DBit
                elif wkbFlatten(eGType) == ogr.wkbGeometryCollection:
                    eGType = ogr.wkbUnknown | n25DBit

            if pszZField is not None:
                eGType = eGType | ogr.wkb25DBit

        if poDstDS.TestCapability(ogr.ODsCCreateLayer) == False:
            print("Layer " + pszNewLayerName + "not found, and CreateLayer not supported by driver.")
            return False

        gdal.ErrorReset()

        poDstLayer = poDstDS.CreateLayer(pszNewLayerName, poOutputSRS, \
                                            eGType, papszLCO)

if poDstDS.DeleteLayer(iLayer) != 0:
            print("DeleteLayer() failed when overwrite requested.")
            return None

        poDstLayer = None

#/* -------------------------------------------------------------------- */
#/*      If the layer does not exist, then create it.                    */
#/* -------------------------------------------------------------------- */
    if poDstLayer is None:
        if eGType == -2:
            eGType = poSrcFDefn.GetGeomType()

            n25DBit = eGType & ogr.wkb25DBit
            if bPromoteToMulti:
                if wkbFlatten(eGType) == ogr.wkbLineString:
                    eGType = ogr.wkbMultiLineString | n25DBit
                elif wkbFlatten(eGType) == ogr.wkbPolygon:
                    eGType = ogr.wkbMultiPolygon | n25DBit

            if bExplodeCollections:
                if wkbFlatten(eGType) == ogr.wkbMultiPoint:
                    eGType = ogr.wkbPoint | n25DBit
                elif wkbFlatten(eGType) == ogr.wkbMultiLineString:
                    eGType = ogr.wkbLineString | n25DBit
                elif wkbFlatten(eGType) == ogr.wkbMultiPolygon:
                    eGType = ogr.wkbPolygon | n25DBit
                elif wkbFlatten(eGType) == ogr.wkbGeometryCollection:
                    eGType = ogr.wkbUnknown | n25DBit

            if pszZField is not None:
                eGType = eGType | ogr.wkb25DBit

bForceToPolygon = False
    bForceToMultiPolygon = False
    bForceToMultiLineString = False

    poDstLayer = psInfo.poDstLayer
    #papszTransformOptions = psInfo.papszTransformOptions
    poCT = psInfo.poCT
    panMap = psInfo.panMap
    iSrcZField = psInfo.iSrcZField

    if poOutputSRS is None and not bNullifyOutputSRS:
        poOutputSRS = poSrcLayer.GetSpatialRef()

    if wkbFlatten(eGType) == ogr.wkbPolygon:
        bForceToPolygon = True
    elif wkbFlatten(eGType) == ogr.wkbMultiPolygon:
        bForceToMultiPolygon = True
    elif wkbFlatten(eGType) == ogr.wkbMultiLineString:
        bForceToMultiLineString = True

#/* -------------------------------------------------------------------- */
#/*      Transfer features.                                              */
#/* -------------------------------------------------------------------- */
    nFeaturesInTransaction = 0
    nCount = 0

    if nGroupTransactions > 0:
        poDstLayer.StartTransaction()

    while True:
        poDstFeature = None

#/*      Open data source.                                               */
#/* -------------------------------------------------------------------- */
    if isinstance(pszDataSource, basestring):
        poDS = ogr.Open(pszDataSource, False)
    else:
        poDS = pszDataSource

#/* -------------------------------------------------------------------- */
#/*      Report failure                                                  */
#/* -------------------------------------------------------------------- */
    if poDS is None:
        print("FAILURE:\n" +
              "Unable to open datasource `%s' with the following drivers." % pszDataSource)

        for iDriver in range(ogr.GetDriverCount()):
            print("  ->  " + ogr.GetDriver(iDriver).GetName())

        return False

#/* -------------------------------------------------------------------- */
#/*      Try opening the output datasource as an existing, writable      */
#/* -------------------------------------------------------------------- */
    poODS = None
    poDriver = None

    if bUpdate:
        poODS = ogr.Open(pszDestDataSource, True)
        if poODS is None:

            if bOverwrite or bAppend:
                poODS = ogr.Open(pszDestDataSource, False)
                if poODS is None:

print( "Usage: ogr2ogr [--help-general] [-skipfailures] [-append] [-update] [-gt n]\n" + \
            "               [-select field_list] [-where restricted_where] \n" + \
            "               [-progress] [-sql ] \n" + \
            "               [-spat xmin ymin xmax ymax] [-preserve_fid] [-fid FID]\n" + \
            "               [-a_srs srs_def] [-t_srs srs_def] [-s_srs srs_def]\n" + \
            "               [-f format_name] [-overwrite] [[-dsco NAME=VALUE] ...]\n" + \
            "               [-simplify tolerance]\n" + \
            #// "               [-segmentize max_dist] [-fieldTypeToString All|(type1[,type2]*)]\n" + \
            "               [-fieldTypeToString All|(type1[,type2]*)] [-explodecollections] \n" + \
            "               dst_datasource_name src_datasource_name\n" + \
            "               [-lco NAME=VALUE] [-nln name] [-nlt type] [-dim 2|3] [layer [layer ...]]\n" + \
            "\n" + \
            " -f format_name: output file format name, possible values are:")

    for iDriver in range(ogr.GetDriverCount()):
        poDriver = ogr.GetDriver(iDriver)

        if poDriver.TestCapability( ogr.ODrCCreateDataSource ):
            print( "     -f \"" + poDriver.GetName() + "\"" )

    print( " -append: Append to existing layer instead of creating new if it exists\n" + \
            " -overwrite: delete the output layer and recreate it empty\n" + \
            " -update: Open existing output datasource in update mode\n" + \
            " -progress: Display progress on terminal. Only works if input layers have the \"fast feature count\" capability\n" + \
            " -select field_list: Comma-delimited list of fields from input layer to\n" + \
            "                     copy to the new layer (defaults to all)\n" + \
            " -where restricted_where: Attribute query (like SQL WHERE)\n" + \
            " -sql statement: Execute given SQL statement and save result.\n" + \
            " -skipfailures: skip features or layers that fail to convert\n" + \
            " -gt n: group n features per transaction (default 200)\n" + \
            " -spat xmin ymin xmax ymax: spatial query extents\n" + \
            " -simplify tolerance: distance tolerance for simplification.\n" + \

print("Usage: ogr2ogr [--help-general] [-skipfailures] [-append] [-update] [-gt n]\n" +
          "               [-select field_list] [-where restricted_where] \n" +
          "               [-progress] [-sql ] \n" +
          "               [-spat xmin ymin xmax ymax] [-preserve_fid] [-fid FID]\n" +
          "               [-a_srs srs_def] [-t_srs srs_def] [-s_srs srs_def]\n" +
          "               [-f format_name] [-overwrite] [[-dsco NAME=VALUE] ...]\n" +
          "               [-simplify tolerance]\n" +
          #// "               [-segmentize max_dist] [-fieldTypeToString All|(type1[,type2]*)]\n" +
          "               [-fieldTypeToString All|(type1[,type2]*)] [-explodecollections] \n" +
          "               dst_datasource_name src_datasource_name\n" +
          "               [-lco NAME=VALUE] [-nln name] [-nlt type] [-dim 2|3] [layer [layer ...]]\n" +
          "\n" +
          " -f format_name: output file format name, possible values are:")

    for iDriver in range(ogr.GetDriverCount()):
        poDriver = ogr.GetDriver(iDriver)

        if poDriver.TestCapability(ogr.ODrCCreateDataSource):
            print("     -f \"" + poDriver.GetName() + "\"")

    print(" -append: Append to existing layer instead of creating new if it exists\n" +
          " -overwrite: delete the output layer and recreate it empty\n" +
          " -update: Open existing output datasource in update mode\n" +
          " -progress: Display progress on terminal. Only works if input layers have the \"fast feature count\" capability\n" +
          " -select field_list: Comma-delimited list of fields from input layer to\n" +
          "                     copy to the new layer (defaults to all)\n" +
          " -where restricted_where: Attribute query (like SQL WHERE)\n" +
          " -sql statement: Execute given SQL statement and save result.\n" +
          " -skipfailures: skip features or layers that fail to convert\n" +
          " -gt n: group n features per transaction (default 20000)\n" +
          " -spat xmin ymin xmax ymax: spatial query extents\n" +
          " -simplify tolerance: distance tolerance for simplification.\n" +

"         being updated.")

        if poODS is not None:
            poDriver = poODS.GetDriver()

#/* -------------------------------------------------------------------- */
#/*      Find the output driver.                                         */
#/* -------------------------------------------------------------------- */
    if not bUpdate:
        poDriver = ogr.GetDriverByName(pszFormat)
        if poDriver is None:
            print("Unable to find driver `%s'." % pszFormat)
            print("The following drivers are available:")

            for iDriver in range(ogr.GetDriverCount()):
                print("  ->  %s" % ogr.GetDriver(iDriver).GetName())

            return False

        if poDriver.TestCapability(ogr.ODrCCreateDataSource) == False:
            print("%s driver does not support data source creation." % pszFormat)
            return False

#/* -------------------------------------------------------------------- */
#/*      Special case to improve user experience when translating        */
#/*      a datasource with multiple layers into a shapefile. If the      */
#/*      user gives a target datasource with .shp and it does not exist, */
#/*      the shapefile driver will try to create a file, but this is not */
#/*      appropriate because here we have several layers, so create      */
#/*      a directory instead.                                            */
#/* -------------------------------------------------------------------- */
        if EQUAL(poDriver.GetName(), "ESRI Shapefile") and \

print("Usage: ogr2ogr [--help-general] [-skipfailures] [-append] [-update] [-gt n]\n" + \
            "               [-select field_list] [-where restricted_where] \n" + \
            "               [-progress] [-sql ] \n" + \
            "               [-spat xmin ymin xmax ymax] [-preserve_fid] [-fid FID]\n" + \
            "               [-a_srs srs_def] [-t_srs srs_def] [-s_srs srs_def]\n" + \
            "               [-f format_name] [-overwrite] [[-dsco NAME=VALUE] ...]\n" + \
            "               [-simplify tolerance]\n" + \
            #// "               [-segmentize max_dist] [-fieldTypeToString All|(type1[,type2]*)]\n" + \
            "               [-fieldTypeToString All|(type1[,type2]*)] [-explodecollections] \n" + \
            "               dst_datasource_name src_datasource_name\n" + \
            "               [-lco NAME=VALUE] [-nln name] [-nlt type] [layer [layer ...]]\n" + \
            "\n" + \
            " -f format_name: output file format name, possible values are:")

    for iDriver in range(ogr.GetDriverCount()):
        poDriver = ogr.GetDriver(iDriver)

        if poDriver.TestCapability(ogr.ODrCCreateDataSource):
            print("     -f \"" + poDriver.GetName() + "\"")

    print(" -append: Append to existing layer instead of creating new if it exists\n" + \
            " -overwrite: delete the output layer and recreate it empty\n" + \
            " -update: Open existing output datasource in update mode\n" + \
            " -progress: Display progress on terminal. Only works if input layers have the \"fast feature count\" capability\n" + \
            " -select field_list: Comma-delimited list of fields from input layer to\n" + \
            "                     copy to the new layer (defaults to all)\n" + \
            " -where restricted_where: Attribute query (like SQL WHERE)\n" + \
            " -sql statement: Execute given SQL statement and save result.\n" + \
            " -skipfailures: skip features or layers that fail to convert\n" + \
            " -gt n: group n features per transaction (default 200)\n" + \
            " -spat xmin ymin xmax ymax: spatial query extents\n" + \
            " -simplify tolerance: distance tolerance for simplification.\n" + \