sample spanner code

spanner_sample.py

    spanner_client = spanner.Client()
    instance       = spanner_client.instance("tfgen-spanid-20201027205143024") # <--spanner instance ID here. this is stage's. this should be a variable
    database       = instance.database("workday") # <-- this should probably also be a variable
    TABLE_NAME     = "workers"
    
    #############################
    # this part should be in a separate function, probably
    import csv
    workday_fieldnames = ""
    worker_data = []
    with open('workday_infile.csv', newline='') as csvfile:
        workday_workers_csv = csv.DictReader(csvfile)
       
        workday_fieldnames = workday_workers_csv.fieldnames

        for row in reader:
          worker_data.append(row)
    ##############################

        
    all_workers = spanner.KeySet(all_=True)

    with database.batch() as batch:
        batch.delete(TABLE_NAME, all_workers)
        
        batch.insert(
            table=TABLE_NAME,
            columns=tuple(workday_fieldnames), 
            values=worker_data,
        )