Issue with line containing NULL byte

benberman

The script I currently have reads an existing csv and updates(writes to) the csv by refencing a feature class, its attribute fields, and associated domains from a GDB and then updates the domain values with the corresponding attribute field n

ames, in the spreadsheet(csv).

import arcpy,collections,re,csv
arcpy.env.overwriteOutput = True
workspace= 'path to GDB'
file = 'path to csv'
input= 'path to feature class'
lstflds=arcpy.ListFields(input)
with open(file,"rb+") as f:
    reader=csv.reader(f)
    writer = csv.writer(f)
    mydict = collections.defaultdict(list)
    domains=arcpy.da.ListDomains(workspace)
    for domain in domains:
        if domain.type =='Text':
            coded_values=domain.codedValues
            for code,desc in coded_values.iteritems():
                mydict[domain.name].append(code)
    dict_dom={}
    for fld in lstflds:
        for dom,values in mydict.iteritems():
            if fld.domain==str(dom):
                dict_dom.update({fld.name:values})
    print dict_dom
    for row in reader:
        for key,val in dict_dom.items():
            if row[1]==key:
                char_removal = ["[","'","u"," ","]"]
                rx = '[' + re.escape(''.join(char_removal)) + ']'
                v=re.sub(rx,'', str(val))
                row[3]=v
                print row[3] # This lists the domain codes just fine as they would be written to the spreadsheet
                writer.writerow(row) # This is where the script returns the NULL error

As the last 2 commented lines in the script indicate, there is some kind of a "null byte" error in the writer. I have tried my best to remove any whitespaces/spaces.

How can this be fixed?

benberman

Ok, I was able to solve the issue regarding the NUL bytes and the Nonetype keys in the DictWriter. The code works now. Thanks to everyone for your input.

import arcpy,collections,re,csv
arcpy.env.overwriteOutput = True

workspace= # path to workspace
file = # path to csv to be read
outfile= # path to csv to be written
input= # path to reference feature_class

lstflds=arcpy.ListFields(input)
with open(file, 'rb') as csvfile:
    with open(outfile,'wb') as f:
        field_names=['Rule','Attribute','Operator','Value','ERROR1',  
           'ERROR2','FIXED','Feature Class']

        reader = csv.DictReader(csvfile,field_names,delimiter=',')
        writer=csv.DictWriter(f,field_names)
        for row in reader:
            if None in row:
                del row[None]
                mydict = collections.defaultdict(list)
                domains=arcpy.da.ListDomains(workspace)
                for domain in domains:
                    if domain.type =='Text':
                        coded_values=domain.codedValues
                        for code,desc in coded_values.iteritems():
                            mydict[domain.name].append(code)
                dict_dom={}
                for fld in lstflds:
                    for dom,values in mydict.iteritems():
                        if fld.domain==str(dom):
                            dict_dom.update({fld.name:values})
                for keys,vals in dict_dom.iteritems():
                    if keys == row['Attribute']:
                        char_removal = ["[","'","u"," ","]"]
                        rx = '[' + re.escape(''.join(char_removal)) + ']'
                        v=re.sub(rx,'', str(vals))
                        row['Value']= v.replace('\x00','')
                writer.writerow(row)