Macros reference

Variables and macros can be used in templates (see the Jinja Templating section)

The following come for free out of the box with Airflow. Additional custom macros can be added globally through ORM Extensions, or at a DAG level through the DAG.user_defined_macros argument.

Default Variables

The Airflow engine passes a few variables by default that are accessible in all templates

Variable

Description

{{ ds }}

the execution date as YYYY-MM-DD

{{ ds_nodash }}

the execution date as YYYYMMDD

{{ prev_ds }}

the previous execution date as YYYY-MM-DD if {{ ds }} is 2018-01-08 and schedule_interval is @weekly, {{ prev_ds }} will be 2018-01-01

{{ prev_ds_nodash }}

the previous execution date as YYYYMMDD if exists, else None

{{ next_ds }}

the next execution date as YYYY-MM-DD if {{ ds }} is 2018-01-01 and schedule_interval is @weekly, {{ next_ds }} will be 2018-01-08

{{ next_ds_nodash }}

the next execution date as YYYYMMDD if exists, else None

{{ yesterday_ds }}

the day before the execution date as YYYY-MM-DD

{{ yesterday_ds_nodash }}

the day before the execution date as YYYYMMDD

{{ tomorrow_ds }}

the day after the execution date as YYYY-MM-DD

{{ tomorrow_ds_nodash }}

the day after the execution date as YYYYMMDD

{{ ts }}

same as execution_date.isoformat(). Example: 2018-01-01T00:00:00+00:00

{{ ts_nodash }}

same as ts without -, : and TimeZone info. Example: 20180101T000000

{{ ts_nodash_with_tz }}

same as ts without - and :. Example: 20180101T000000+0000

{{ execution_date }}

the execution_date (pendulum.Pendulum)

{{ prev_execution_date }}

the previous execution date (if available) (pendulum.Pendulum)

{{ prev_execution_date_success }}

execution date from prior successful dag run (if available) (pendulum.Pendulum)

{{ prev_start_date_success }}

start date from prior successful dag run (if available) (pendulum.Pendulum)

{{ next_execution_date }}

the next execution date (pendulum.Pendulum)

{{ dag }}

the DAG object

{{ task }}

the Task object

{{ macros }}

a reference to the macros package, described below

{{ task_instance }}

the task_instance object

{{ end_date }}

same as {{ ds }}

{{ latest_date }}

same as {{ ds }}

{{ ti }}

same as {{ task_instance }}

{{ params }}

a reference to the user-defined params dictionary which can be overridden by the dictionary passed through trigger_dag -c if you enabled dag_run_conf_overrides_params` in ``airflow.cfg

{{ var.value.my_var }}

global defined variables represented as a dictionary

{{ var.json.my_var.path }}

global defined variables represented as a dictionary with deserialized JSON object, append the path to the key within the JSON object

{{ task_instance_key_str }}

a unique, human-readable key to the task instance formatted {dag_id}_{task_id}_{ds}

{{ conf }}

the full configuration object located at airflow.configuration.conf which represents the content of your airflow.cfg

{{ run_id }}

the run_id of the current DAG run

{{ dag_run }}

a reference to the DagRun object

{{ test_mode }}

whether the task instance was called using the CLI’s test subcommand

Note that you can access the object’s attributes and methods with simple dot notation. Here are some examples of what is possible: {{ task.owner }}, {{ task.task_id }}, {{ ti.hostname }}, … Refer to the models documentation for more information on the objects’ attributes and methods.

The var template variable allows you to access variables defined in Airflow’s UI. You can access them as either plain-text or JSON. If you use JSON, you are also able to walk nested structures, such as dictionaries like: {{ var.json.my_dict_var.key1 }}.

It is also possible to fetch a variable by string if needed with {{ var.value.get('my.var', 'fallback') }} or {{ var.json.get('my.dict.var', {'key1': 'val1'}) }}. Defaults can be supplied in case the variable does not exist.

Macros

Macros are a way to expose objects to your templates and live under the macros namespace in your templates.

A few commonly used libraries and methods are made available.

Variable

Description

macros.datetime

The standard lib’s datetime.datetime

macros.timedelta

The standard lib’s datetime.timedelta

macros.dateutil

A reference to the dateutil package

macros.time

The standard lib’s datetime.time

macros.uuid

The standard lib’s uuid

macros.random

The standard lib’s random

Some airflow specific macros are also defined:

airflow.macros.datetime_diff_for_humans(dt, since=None)[source]

Return a human-readable/approximate difference between two datetimes, or one and now.

Parameters

  • dt (datetime) – The datetime to display the diff for

  • since (None or datetime) – When to display the date from. If None then the diff is between dt and now.

Return type

str

airflow.macros.ds_add(ds, days)[source]

Add or subtract days from a YYYY-MM-DD

Parameters

  • ds (str) – anchor date in YYYY-MM-DD format to add to

  • days (int) – number of days to add to the ds, you can use negative values

>>> ds_add('2015-01-01', 5)
'2015-01-06'
>>> ds_add('2015-01-06', -5)
'2015-01-01'
airflow.macros.ds_format(ds, input_format, output_format)[source]

Takes an input string and outputs another string as specified in the output format

Parameters

  • ds (str) – input string which contains a date

  • input_format (str) – input string format. E.g. %Y-%m-%d

  • output_format (str) – output string format E.g. %Y-%m-%d

>>> ds_format('2015-01-01', "%Y-%m-%d", "%m-%d-%y")
'01-01-15'
>>> ds_format('1/5/2015', "%m/%d/%Y",  "%Y-%m-%d")
'2015-01-05'
airflow.macros.random() → x in the interval [0, 1).
airflow.macros.hive.closest_ds_partition(table, ds, before=True, schema='default', metastore_conn_id='metastore_default')[source]

This function finds the date in a list closest to the target date. An optional parameter can be given to get the closest before or after.

Parameters

  • table (str) – A hive table name

  • ds (list[datetime.date]) – A datestamp %Y-%m-%d e.g. yyyy-mm-dd

  • before (bool or None) – closest before (True), after (False) or either side of ds

  • schema (str) – table schema

  • metastore_conn_id (str) – which matastore connection to use

Returns

The closest date

Return type

str or None

>>> tbl = 'airflow.static_babynames_partitioned'
>>> closest_ds_partition(tbl, '2015-01-02')
'2015-01-01'
airflow.macros.hive.max_partition(table, schema='default', field=None, filter_map=None, metastore_conn_id='metastore_default')[source]

Gets the max partition for a table.

Parameters

  • schema (str) – The hive schema the table lives in

  • table (str) – The hive table you are interested in, supports the dot notation as in “my_database.my_table”, if a dot is found, the schema param is disregarded

  • metastore_conn_id (str) – The hive connection you are interested in. If your default is set you don’t need to use this parameter.

  • filter_map (map) – partition_key:partition_value map used for partition filtering, e.g. {‘key1’: ‘value1’, ‘key2’: ‘value2’}. Only partitions matching all partition_key:partition_value pairs will be considered as candidates of max partition.

  • field (str) – the field to get the max value from. If there’s only one partition field, this will be inferred

>>> max_partition('airflow.static_babynames_partitioned')
'2015-01-01'

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