title | description | date |
---|---|---|
Python quick example using HTTP requests module |
An example using Python and requests module to write and read to ClickHouse |
2022-07-10 |
Can I just run HTTP requests to ClickHouse server using requests module?
Yes, here is the sample code.
import requests
import datetime
create_replace_stmt = 'CREATE OR REPLACE TABLE test_table (name String, age UInt8) Engine=MergeTree ORDER BY tuple();'
select_query = 'SELECT count() FROM test_table'
insert_query = 'INSERT INTO test_table SELECT * FROM generateRandom(\'name String, age UInt8\',1,1) LIMIT 300000000'
CH_URL = 'https://your_clickhouse_service_fqdn:8443'
CH_USER = 'default'
CH_PASSWORD = 'secret_pwd'
headers = {}
headers["X-ClickHouse-User"] = CH_USER
headers["X-ClickHouse-Key"] = CH_PASSWORD
now = (datetime.datetime.now())
print("{} - starting...".format(now))
# create/replace table
now = (datetime.datetime.now())
print("{} - creating/replacing table...".format(now))
response = requests.post(url=CH_URL,
params={"database": "default",
"query": create_replace_stmt,
"session_id": "my-session-id-string"
},
headers=headers)
# select count()
response = requests.post(url=CH_URL,
params={"database": "default",
"query": select_query,
"session_id": "my-session-id-string"
},
headers=headers)
now = (datetime.datetime.now())
print("{} - elements in test_table before insert: {}".format(
now, response.content.decode('utf-8')))
# insert
now = (datetime.datetime.now())
print("{} - Inserting data...".format(now))
response = requests.post(url=CH_URL,
params={"database": "default",
"query": insert_query,
"session_id": "my-session-id-string",
"wait_end_of_query": 1
},
headers=headers)
now = (datetime.datetime.now())
print("{} - Done inserting data...".format(now))
response = requests.post(url=CH_URL,
params={"database": "default",
"query": select_query,
"session_id": "my-session-id-string",
},
headers=headers)
now = (datetime.datetime.now())
print("{} - elements in test_table after insert: {}".format(
now, response.content.decode('utf-8')))
Sample expected output:
(venv) ➜ venv/bin/python main.py
2023-07-07 14:54:27.336450 - starting...
2023-07-07 14:54:27.336476 - creating/replacing table...
2023-07-07 14:54:28.125270 - elements in test_table before insert: 0
2023-07-07 14:54:28.125352 - Inserting data...
2023-07-07 14:55:23.788466 - Done inserting data...
2023-07-07 14:55:23.962134 - elements in test_table after insert: 299115357
requirements.txt
requests==2.31.0
See this other KB for steps on how setup your python venv.