Loading multiple csv into BQ table on event trigger

i am trying to load multiple csv files into table by below code but it is failing: Can anyone let me know where i am wrong: ##################

def csv_loader(data, context):
        client = bigquery.Client()
        dataset_id = os.environ['DATASET']
        dataset_ref = client.dataset(dataset_id)
        job_config = bigquery.LoadJobConfig(
        source_format=bigquery.SourceFormat.CSV,
        field_delimiter="|",
        write_disposition="WRITE_TRUNCATE",
        skip_leading_rows=1,
         )

        # get the URI for uploaded CSV in GCS from 'data'
        uri = 'gs://' + os.environ['BUCKET'] + '/' + data['name']
        # lets do this
        load_job = client.load_table_from_uri(
                uri,
                dataset_ref.table(os.environ['TABLE'])

        load_job.result()  # wait for table load to complete.
        print('Job finished.')
        destination_table = client.get_table(dataset_ref.table(os.environ['TABLE']))
        print('Loaded {} rows.'.format(destination_table.num_rows))

###################

Above works fine if schema is mentioned for one file but with multiple files gives error.Can anyone tell me what I am doing wrong

Based on your last comment, schemas are different and you want to use schema auto detect. However, I don't see the flag in your code and neither see you passing the job_config variable in the job load method.

Try something as below:

Note: I added the flag autodetect=True, in the job_config variable and also passed the job_config variable in the load_table_from_uri() function.

def csv_loader(data, context):
        client = bigquery.Client()
        dataset_id = os.environ['DATASET']
        dataset_ref = client.dataset(dataset_id)
        job_config = bigquery.LoadJobConfig(
        autodetect=True,
        source_format=bigquery.SourceFormat.CSV,
        field_delimiter="|",
        write_disposition="WRITE_TRUNCATE",
        skip_leading_rows=1,
         )

        # get the URI for uploaded CSV in GCS from 'data'
        uri = 'gs://' + os.environ['BUCKET'] + '/' + data['name']
        # lets do this
        load_job = client.load_table_from_uri(
                uri,
                dataset_ref.table(os.environ['TABLE'],
                job_config=job_config
               )

        load_job.result()  # wait for table load to complete.
        print('Job finished.')
        destination_table = client.get_table(dataset_ref.table(os.environ['TABLE']))
        print('Loaded {} rows.'.format(destination_table.num_rows))