Script Development / Connector Object DFF.CONN / InfluxDB

The InfluxDB connector operation object is a wrapper of the Python third-party package influxdb (version 5.3.1), mainly providing methods for querying and writing to InfluxDB. This connector is compatible with the following databases:

• Alibaba Cloud Time Series Database InfluxDB Edition

This connector connects based on the HTTP protocol

The parameters of DFF.CONN(...) are as follows:

Parameter	Type	Required / Default	Description
connector_id	str	Required	Connector ID
database	str	None	Database to use

.query(...)

Executes an InfluxQL statement. The parameters are as follows:

Parameter	Type	Required / Default	Description
sql	str	Required	InfluxQL statement, which can contain bind parameter placeholders in the form of $var_name
bind_params	dict	None	Bind parameters
database	str	None	Database to use for this query
dict_output	bool	False	Whether to convert each row of data into the {column_name: value} form

sql = 'SELECT * FROM demo WHERE city = $city LIMIT 5'
bind_params = {'city': 'hangzhou'}
result = db.query(sql, bind_params=bind_params, database='demo')

{'series': [{'columns': ['time', 'city', 'hostname', 'status', 'value'], 'name': 'demo', 'values': [['2018-12-31T16:00:10Z', 'hangzhou', 'webserver', 'UNKNOWN', 90], ['2018-12-31T16:00:20Z', 'hangzhou', 'jira', 'running', 40], ['2018-12-31T16:00:50Z', 'hangzhou', 'database', 'running', 50], ['2018-12-31T16:01:00Z', 'hangzhou', 'jira', 'stopped', 40], ['2018-12-31T16:02:00Z', 'hangzhou', 'rancher', 'UNKNOWN', 90]]}]}

sql = 'SELECT * FROM demo WHERE city = $city LIMIT 5'
bind_params = {'city': 'hangzhou'}
result = db.query(sql, bind_params=bind_params, database='demo', dict_output=True)

{'series': [[{'city': 'hangzhou', 'hostname': 'webserver', 'status': 'UNKNOWN', 'time': '2018-12-31T16:00:10Z', 'value': 90}, {'city': 'hangzhou', 'hostname': 'jira', 'status': 'running', 'time': '2018-12-31T16:00:20Z', 'value': 40}, {'city': 'hangzhou', 'hostname': 'database', 'status': 'running', 'time': '2018-12-31T16:00:50Z', 'value': 50}, {'city': 'hangzhou', 'hostname': 'jira', 'status': 'stopped', 'time': '2018-12-31T16:01:00Z', 'value': 40}, {'city': 'hangzhou', 'hostname': 'rancher', 'status': 'UNKNOWN', 'time': '2018-12-31T16:02:00Z', 'value': 90}]]}

A single query returns a dict; when the driver returns multiple result sets for multiple statements, this method returns list[dict].

.query2(...)

The query2(...) method is also used to execute InfluxQL statements, but the parameter placeholder is different, using the question mark ? as the parameter placeholder. The parameters are as follows:

Parameter	Type	Required / Default	Description
sql	str	Required	InfluxQL statement, which can contain parameter placeholders. ? indicates a parameter that needs escaping; ?? indicates a parameter that does not need escaping
sql_params	list	None	InfluxQL parameters
database	str	None	Database to use for this query
dict_output	bool	False	Whether to convert each row of data into the {"column name": "value"} form

sql = 'SELECT * FROM ?? WHERE city = ? LIMIT 5'
sql_params = ['demo', 'hangzhou']
result = db.query2(sql, sql_params=sql_params, dict_output=True)

Dynamic SQL Statement

query2(...) internally uses DFF.SQL(...) to construct SQL statements and supports constructing complex dynamic SQL statements.

For example, WHERE IN (...) with an uncertain number of values, or INSERT INTO ... VALUES ... for batch writing data, etc.

For details, please refer to Script Development / SQL Construction DFF.SQL

.switch_database(...)

Switch the default database used for subsequent requests of the current operation object.

Parameter	Type	Required / Default	Description
database	str	Required	Database name

db.switch_database('archive')
result = db.query('SELECT * FROM demo LIMIT 5')

If you only need to specify a database for a single query or write, you should prefer using the database parameter of the corresponding method.

.write_point(...)

Added in version 1.1.13

Writes a single data point. The parameters are as follows:

Parameter	Type	Required / Default	Description
measurement	str	Required	Measurement
fields	dict{str: str/int/float/bool}	Required	Field Key name must be str Key value can be str/int/float/bool
tags	dict{str: str}	None	Tag Both key names and key values must be str
timestamp	str/int	None	Time ISO format, e.g., 2020-01-01T01:02:03Z UNIX timestamp, e.g., 1577840523
database	str	None	Specify the database for this write

fields = { 'cpu': 100, 'mem': 0.5 }
tags   = { 'host': 'web001' }
result = db.write_point(measurement='host_monitor', fields=fields, tags=tags)

.write_points(...)

Added in version 1.1.13

Writes data points in batch. The parameters are as follows:

Parameter	Type	Required / Default	Description
points	list	Required	Array of data points
points[#]['measurement']	str	Required	Measurement
points[#]['fields']	dict{str: str/int/float/bool}	Required	Field Key name must be str Key value can be str/int/float/bool
points[#]['tags']	dict{str: str}	None	Tag Both key names and key values must be str
points[#]['time']	str/int	None	Time ISO format, e.g., 2020-01-01T01:02:03Z UNIX timestamp, e.g., 1577840523
database	str	None	Specify the database for this write

points = [
    {
        'measurement': 'host_monitor',
        'fields'     : { 'cpu': 100, 'mem': 0.5 },
        'tags'       : { 'host': 'web001' },
    }
]
result = db.write_points(points)