Hello everyone. I have just begun working with meltano and am figuring out how to configure it. I am trying to use the airflow plugin but am running into an error that I'm not sure how to debug. I can see from the airflow UI the error -

*** Found local files:
***   * /lana/.meltano/utilities/airflow/logs/dag_id=meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery/run_id=manual__2025-01-24T06:44:29.542923+00:00/task_id=meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0/attempt=1.log
[2025-01-24, 06:44:32 UTC] {taskinstance.py:1956} INFO - Dependencies all met for dep_context=non-requeueable deps ti=<TaskInstance: meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery.meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0 manual__2025-01-24T06:44:29.542923+00:00 [queued]>
[2025-01-24, 06:44:32 UTC] {taskinstance.py:1956} INFO - Dependencies all met for dep_context=requeueable deps ti=<TaskInstance: meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery.meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0 manual__2025-01-24T06:44:29.542923+00:00 [queued]>
[2025-01-24, 06:44:32 UTC] {taskinstance.py:2170} INFO - Starting attempt 1 of 2
[2025-01-24, 06:44:32 UTC] {taskinstance.py:2191} INFO - Executing <Task(BashOperator): meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0> on 2025-01-24 06:44:29.542923+00:00
[2025-01-24, 06:44:32 UTC] {standard_task_runner.py:60} INFO - Started process 196 to run task
[2025-01-24, 06:44:32 UTC] {standard_task_runner.py:87} INFO - Running: ['airflow', 'tasks', 'run', 'meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery', 'meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0', 'manual__2025-01-24T06:44:29.542923+00:00', '--job-id', '7', '--raw', '--subdir', 'DAGS_FOLDER/meltano_dag_generator.py', '--cfg-path', '/tmp/tmp5dejr3en']
[2025-01-24, 06:44:32 UTC] {standard_task_runner.py:88} INFO - Job 7: Subtask meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0
[2025-01-24, 06:44:32 UTC] {task_command.py:423} INFO - Running <TaskInstance: meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery.meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0 manual__2025-01-24T06:44:29.542923+00:00 [running]> on host 8216cb4d1c99
[2025-01-24, 06:44:32 UTC] {taskinstance.py:2480} INFO - Exporting env vars: AIRFLOW_CTX_DAG_OWNER='airflow' AIRFLOW_CTX_DAG_ID='meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery' AIRFLOW_CTX_TASK_ID='meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0' AIRFLOW_CTX_EXECUTION_DATE='2025-01-24T06:44:29.542923+00:00' AIRFLOW_CTX_TRY_NUMBER='1' AIRFLOW_CTX_DAG_RUN_ID='manual__2025-01-24T06:44:29.542923+00:00'
[2025-01-24, 06:44:32 UTC] {subprocess.py:63} INFO - Tmp dir root location: /tmp
[2025-01-24, 06:44:32 UTC] {subprocess.py:75} INFO - Running command: ['/usr/bin/bash', '-c', 'cd /lana; .meltano/run/bin run tap-postgres']
[2025-01-24, 06:44:32 UTC] {subprocess.py:86} INFO - Output:
[2025-01-24, 06:44:33 UTC] {subprocess.py:93} INFO - [2m2025-01-24T06:44:33.593498Z[0m [[32m[1minfo     [0m] [1mEnvironment 'dev' is active   [0m
[2025-01-24, 06:44:33 UTC] {subprocess.py:93} INFO - Need help fixing this problem? Visit <http://melta.no/> for troubleshooting steps, or to
[2025-01-24, 06:44:33 UTC] {subprocess.py:93} INFO - join our friendly Slack community.
[2025-01-24, 06:44:33 UTC] {subprocess.py:93} INFO - 
[2025-01-24, 06:44:33 UTC] {subprocess.py:93} INFO - block violates set requirements: Loader missing in block set!
[2025-01-24, 06:44:35 UTC] {subprocess.py:97} INFO - Command exited with return code 1
[2025-01-24, 06:44:35 UTC] {taskinstance.py:2698} ERROR - Task failed with exception
Traceback (most recent call last):
  File "/lana/.meltano/utilities/airflow/venv/lib/python3.9/site-packages/airflow/models/taskinstance.py", line 433, in _execute_task
    result = execute_callable(context=context, **execute_callable_kwargs)
  File "/lana/.meltano/utilities/airflow/venv/lib/python3.9/site-packages/airflow/operators/bash.py", line 212, in execute
    raise AirflowException(
airflow.exceptions.AirflowException: Bash command failed. The command returned a non-zero exit code 1.
[2025-01-24, 06:44:35 UTC] {taskinstance.py:1138} INFO - Marking task as UP_FOR_RETRY. dag_id=meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery, task_id=meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0, execution_date=20250124T064429, start_date=20250124T064432, end_date=20250124T064435
[2025-01-24, 06:44:35 UTC] {standard_task_runner.py:107} ERROR - Failed to execute job 7 for task meltano_postgres-to-bigquery_tap-postgres-to-target-bigquery_task0 (Bash command failed. The command returned a non-zero exit code 1.; 196)
[2025-01-24, 06:44:35 UTC] {local_task_job_runner.py:234} INFO - Task exited with return code 1
[2025-01-24, 06:44:35 UTC] {taskinstance.py:3280} INFO - 0 downstream tasks scheduled from follow-on schedule check

The error

block violates set requirements: Loader missing in block set!

seems to be the primary error here. Any idea how I can fix this? If I try to run the same job manually with

meltano run

it runs successfully without any errors. Edit: I was able to solve this issue. The problem was that I'd defined my job in the wrong way. It was

jobs:
- name: tap-postgres-to-target-bigquery
  tasks:
  - tap-postgres
  - target-bigquery

but changing it to

jobs:
- name: tap-postgres-to-target-bigquery
  tasks:
  - tap-postgres target-bigquery

fixed the problem

Yep, each item in the tasks list needs to be a valid command to be passed to

meltano run

More examples here: https://docs.meltano.com/reference/command-line-interface/#tasks