Demo on how to upload to BigQuery with python3. See https://notes.webutvikling.org/starting-bigquery/

bigquery_import.py

# 1. install dependencies 
# 2. Set service account json in code
#    or with env var "SA_ACCOUNT"
# 3. Run this file to import test data:
#   "python3 bigquery_import.py"

import os
import json

from google.cloud import bigquery
from google.oauth2.service_account import Credentials

import pandas


TABLE_NAME = 'nameexample'
DATASET_NAME = 'example'


def get_service_account():
    service_account_json = os.environ.get('SA_CREDENTIALS')
    
    # For local testing, you can comment out the lines below, and use your
    #   service account json file downloaded from google cloud
    #
    # service_account_json = json.loads({
    #   "type": "service_account",
    #   "project_id": "myexampleproject",
    #   "private_key_id": "975c1e87f065c76c9915887acc1afedeb59600b0",
    #   "private_key": "-----BEGIN PRIVATE KEY-----\ndummyexample/12345\==\n-----END PRIVATE KEY-----\n",
    #   "client_email": "firebase-adminsdk-r1to@myexampleproject.iam.gserviceaccount.com",
    #   "client_id": "123457110251480388426",
    #   "auth_uri": "https://accounts.google.com/o/oauth2/auth",
    #   "token_uri": "https://oauth2.googleapis.com/token",
    #   "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
    #   "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/firebase-adminsdk-r7tvo%40myexampleproject.iam.gserviceaccount.com"
    # })

    if not service_account_json:
        raise Exception('Missing env var SA_CREDENTIALS')

    try: 
        service_account = json.loads(service_account_json)
    except Exception:
        print('Could not load SA_CREDENTIALS as json!')
        raise

    pk = service_account.get('private_key')
    service_account['private_key'] = pk.replace('\\n', '\n')

    try:
        # This validates data
        Credentials.from_service_account_info(
            service_account
        )
        return service_account
    except Exception:
        print('JSON credentials are wrong or malformatted!')
        raise


def get_project_id():
    sa = get_service_account()
    return sa['project_id']


def get_client():
    service_account = get_service_account()
    google_credentials = Credentials.from_service_account_info(
        service_account
    )
    client = bigquery.Client(credentials=google_credentials)
    return client


def _create_dataset(*, project_id: str, dataset_name: str):
    client = get_client()

    dataset_id = f'{project_id}.{dataset_name}'
    dataset = bigquery.Dataset(dataset_id)

    dataset.location = "europe-north1"
    dataset = client.create_dataset(
        dataset,
        timeout=30
    )
    print(f'Created dataset {dataset.project}.{dataset.dataset_id}')
    return dataset


def _create_table(
        *,
        project_id: str,
        dataset_name: str,
        table_name: str,
        schema
):
    client = get_client()

    table = bigquery.Table(
        f"{project_id}.{dataset_name}.{table_name}",
        schema=schema,
    )
    table = client.create_table(table)
    print(f'Created table {table.project}.{table.dataset_id}.{table.table_id}')
    return table


def _delete_dataset(*, project_id: str, dataset_name: str):
    client = get_client()

    dataset_id = f'{project_id}.{dataset_name}'
    dataset = bigquery.Dataset(dataset_id)

    dataset.location = "europe-north1"
    client.delete_dataset(
        dataset,
        timeout=30
    )
    print(f'Deleted dataset {dataset_id}')
    return dataset


def _delete_table(
        *,
        project_id: str,
        dataset_name: str,
        table_name: str,
):
    client = get_client()

    table_id = f"{project_id}.{dataset_name}.{table_name}"
    table = client.delete_table(table_id)
    print(f'Deleted table {table_id}')
    return table


def do_initial_setup():
    project_id = get_project_id()
    _create_dataset(
        project_id=project_id,
        dataset_name=DATASET_NAME,
    )
    _create_table(
        project_id=project_id,
        dataset_name=DATASET_NAME,
        table_name=TABLE_NAME,
        schema=bq_schema
    )


def send_to_bq(report_records):
    client = get_client()
    project_id = get_project_id()
    dataframe = pandas.DataFrame(
        report_records,
        # In the loaded table, the column order reflects the order of the
        # columns in the DataFrame.
        columns=bq_columns,
    )
    job_config = bigquery.LoadJobConfig(
        # Specify a (partial) schema. All columns are always written to the
        # table. The schema is used to assist in data type definitions.
        schema=bq_schema,
        # Optionally, set the write disposition. BigQuery appends loaded rows
        # to an existing table by default, but with WRITE_TRUNCATE writeF
        # disposition it replaces the table with the loaded data.
        write_disposition="WRITE_TRUNCATE",
    )
    job = client.load_table_from_dataframe(
        dataframe,
        project=project_id,
        destination=f'{DATASET_NAME}.{TABLE_NAME}',
        job_config=job_config
    )
    job.result()  # Wait for the job to complete.
    print(f'Uploaded todays records to {DATASET_NAME}.{TABLE_NAME}')


bq_types = {
    'first_name': bigquery.enums.SqlTypeNames.STRING,
    'last_name': bigquery.enums.SqlTypeNames.STRING,
}

bq_columns = list(bq_types.keys())
bq_schema = list(map(
    lambda item: bigquery.SchemaField(item[0], item[1]),
    bq_types.items()
))


if __name__ == "__main__":
    print(f'Creating {DATASET_NAME}.{TABLE_NAME}')
    try:
        get_service_account()
    except Exception:
        print(f'Could not get service account. Is service account json set?')
        raise

    try:
       do_initial_setup()
    except Exception:
        print('Could not add table. Assuming it has already been created. Continuing.')

    data = [
        { 
            'first_name': 'Tomas', 
            'last_name': 'Albertsen' 
        }
    ]

    send_to_bq(data)

requirements.txt

# Import these dependencies with 
# "pip install -r requirements.txt"

pandas==1.3.2
requests==2.26.0
google-auth==2.0.1
google-cloud-bigquery==2.28.1
pyarrow==5.0.0