Airflow - Template Variables

📌 Most Useful Airflow Template Variables

🧩 Task Instance Context

Variable	Meaning
ti	The TaskInstance object. Commonly used.
task_instance	Same as ti — full TaskInstance object.
task	The task object (operator instance).
task_instance_key_str	Unique identifier for this task instance (DAG ID + task ID + run date).

Example usage:

echo "Running: {{ task_instance_key_str }}"

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🗓️ Execution Time / Dates

Variable	Meaning
ds	Execution date as YYYY-MM-DD.
ds_nodash	Execution date as YYYYMMDD.
ts	Execution timestamp (ISO8601).
ts_nodash	Timestamp without dashes.
logical_date	Pendulum datetime of the logical (scheduled) execution date (same as execution_date).
next_ds	Next execution date (string).
prev_ds	Previous execution date (string).
next_execution_date	Next logical execution datetime.
prev_execution_date	Previous logical execution datetime.
macros.*	All Airflow macro helpers.

Example:

echo "Date: {{ ds }} Next: {{ next_ds }}"

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🧳 DAG-related

Variable	Meaning
dag	The DAG object.
dag_run	The DAGRun object (contains run_id, conf, etc.).
run_id	The DAG run ID (e.g., manual__2024-01-01T00:00:00+00:00).
conf	Runtime config passed via REST UI/trigger (a dict).
params	DAG-level params.

Example (pull config values):

echo "Passed value: {{ dag_run.conf['my_key'] }}"

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🔄 Data Intervals (Airflow 2.2+)

Airflow newer versions use data intervals:

Variable	Meaning
data_interval_start	Start of data interval (Pendulum datetime).
data_interval_end	End of data interval.

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🔧 Macros (helpers)

Airflow provides many helpers under macros.

Common ones:

Macro	Meaning
macros.ds_add(ds, n)	Add n days to a date.
macros.ds_format(ds, input_fmt, output_fmt)	Transform date format.
macros.datetime	Python datetime module.
macros.timedelta	Python timedelta.
macros.uuid()	Random UUID string.

Example:

echo "{{ macros.ds_add(ds, 7) }}"

---

📚 Quick copy-friendly reference

# Task instance context
{{ ti }}
{{ task_instance }}
{{ task }}
{{ task_instance_key_str }}

# DagRun & config
{{ dag_run }}
{{ run_id }}
{{ conf }}
{{ params }}

# Execution datetime
{{ ds }}
{{ ds_nodash }}
{{ ts }}
{{ ts_nodash }}
{{ logical_date }}

# Data intervals
{{ data_interval_start }}
{{ data_interval_end }}

# Previous/Next execution
{{ prev_ds }}
{{ next_ds }}
{{ prev_execution_date }}
{{ next_execution_date }}

# Macros
{{ macros }}
{{ macros.ds_add(ds, 1) }}
{{ macros.datetime }}
{{ macros.timedelta }}
{{ macros.uuid() }}