access django-apscheduler's jobs properties programmatically - django

I use the django-apscheduler package to run cron (scraping) jobs. the package stores the past jobs with some information/properties (e.g. local runtime, duration etc.) somewhere on the database for display on the admin backend.
When I want to access these information/properties about the jobs programmatically in the views.py (e.g. to show the last runtime of a job in the context/template), how would I do that?

in views.py
from django_apscheduler.models import DjangoJobExecution
for accessing the data of executed Jobs
or
from django_abscheduler.models import Jobs
for accessing the scheduled jobs

Related

Upload to BigQuery from Cloud Storage

Have ~50k compressed (gzip) json files daily that need to be uploaded to BQ with some transformation, no API calls. The size of the files may be up to 1Gb.
What is the most cost-efficient way to do it?
Will appreciate any help.
Most efficient way to use Cloud Data Fusion.
I would suggest below approach
Create cloud function and trigger on every new file upload to uncompress file.
Create datafusion job with GCS file as source and bigquery as sink with desired transformation.
Refer below my youtube video.
https://youtu.be/89of33RcaRw
Here is (for example) one way - https://cloud.google.com/bigquery/docs/loading-data-cloud-storage-json...
... but quickly looking over it however one can see that there are some specific limitations. So perhaps simplicity, customization and maintainability of solution can also be added to your “cost” function.
Not knowing some details (for example read "Limitations" section under my link above, what stack you have/willing/able to use, files names or if your files have nested fields etc etc etc ) my first thought is cloud function service ( https://cloud.google.com/functions/pricing ) that is "listening" (event type = Finalize/Create) to your cloud (storage) bucket where your files land (if you go this route put your storage and function in the same zone [if possible], which will make it cheaper).
If you can code Python here is some started code:
main.py
import pandas as pd
from pandas.io import gbq
from io import BytesIO, StringIO
import numpy as np
from google.cloud import storage, bigquery
import io
def process(event, context):
file = event
# check if its your file can also check for patterns in name
if file['name'] == 'YOUR_FILENAME':
try:
working_file = file['name']
storage_client = storage.Client()
bucket = storage_client.get_bucket('your_bucket_here')
blob = bucket.blob(working_file)
#https://stackoverflow.com/questions/49541026/how-do-i-unzip-a-zip-file-in-google-cloud-storage
zipbytes = io.BytesIO(blob.download_as_string())
#print for logging
print(f"file downloaded, {working_file}")
#read_file_as_df --- check out docs here = https://pandas.pydata.org/docs/reference/api/pandas.read_json.html
# if nested might need to go text --> to dictionary and then do some preprocessing
df = pd.read_json(zipbytes, compression='gzip', low_memory= False)
#write processed to big query
df.to_gbq(destination_table ='your_dataset.your_table',
project_id ='your_project_id',
if_exists = 'append')
print(f"table bq created, {working_file}")
# if you want to delete processed file from your storage to save on storage costs uncomment 2 lines below
# blob.delete()
#print(f"blob delete, {working_file}")
except Exception as e:
print(f"exception occured {e}, {working_file}")
requirements.txt
# Function dependencies, for example:
# package>=version
google-cloud-storage
google-cloud-bigquery
pandas
pandas.io
pandas-gbq
PS
Some alternatives include
Starting up a VM and run your script on a schedule and shutting VM down once process is done ( for example cloud scheduler –-> pub/sub –-> cloud function –-> which starts up your vm --> which then runs your script)
Using app engine to run your script (similar)
Using cloud run to run your script (similar)
Using composer/airflow (not similar to 1,2&3) [ could use all types of approaches including data transfers etc, just not sure what stack you are trying to use or what you already have running ]
Scheduling vertex ai workbook (not similar to 1,2&3, basically write up a jupyter notebook and schedule it to run in vertex ai)
Try to query files directly (https://cloud.google.com/bigquery/external-data-cloud-storage#bq_1) and schedule that query (https://cloud.google.com/bigquery/docs/scheduling-queries) to run (but again not sure about your overall pipeline)
Setup for all (except #5 & #6) just in technical debt to me is not worth it if you can get away with functions
Best of luck,

How to schedule an export from a BigQuery table to Cloud Storage?

I have successfully scheduled my query in BigQuery, and the result is saved as a table in my dataset. I see a lot of information about scheduling data transfer in to BigQuery or Cloud Storage, but I haven't found anything regarding scheduling an export from a BigQuery table to Cloud Storage yet.
Is it possible to schedule an export of a BigQuery table to Cloud Storage so that I can further schedule having it SFTP-ed to me via Google BigQuery Data Transfer Services?
There isn't a managed service for scheduling BigQuery table exports, but one viable approach is to use Cloud Functions in conjunction with Cloud Scheduler.
The Cloud Function would contain the necessary code to export to Cloud Storage from the BigQuery table. There are multiple programming languages to choose from for that, such as Python, Node.JS, and Go.
Cloud Scheduler would send an HTTP call periodically in a cron format to the Cloud Function which would in turn, get triggered and run the export programmatically.
As an example and more specifically, you can follow these steps:
Create a Cloud Function using Python with an HTTP trigger. To interact with BigQuery from within the code you need to use the BigQuery client library. Import it with from google.cloud import bigquery. Then, you can use the following code in main.py to create an export job from BigQuery to Cloud Storage:
# Imports the BigQuery client library
from google.cloud import bigquery
def hello_world(request):
# Replace these values according to your project
project_name = "YOUR_PROJECT_ID"
bucket_name = "YOUR_BUCKET"
dataset_name = "YOUR_DATASET"
table_name = "YOUR_TABLE"
destination_uri = "gs://{}/{}".format(bucket_name, "bq_export.csv.gz")
bq_client = bigquery.Client(project=project_name)
dataset = bq_client.dataset(dataset_name, project=project_name)
table_to_export = dataset.table(table_name)
job_config = bigquery.job.ExtractJobConfig()
job_config.compression = bigquery.Compression.GZIP
extract_job = bq_client.extract_table(
table_to_export,
destination_uri,
# Location must match that of the source table.
location="US",
job_config=job_config,
)
return "Job with ID {} started exporting data from {}.{} to {}".format(extract_job.job_id, dataset_name, table_name, destination_uri)
Specify the client library dependency in the requirements.txt file
by adding this line:
google-cloud-bigquery
Create a Cloud Scheduler job. Set the Frequency you wish for
the job to be executed with. For instance, setting it to 0 1 * * 0
would run the job once a week at 1 AM every Sunday morning. The
crontab tool is pretty useful when it comes to experimenting
with cron scheduling.
Choose HTTP as the Target, set the URL as the Cloud
Function's URL (it can be found by selecting the Cloud Function and
navigating to the Trigger tab), and as HTTP method choose GET.
Once created, and by pressing the RUN NOW button, you can test how the export
behaves. However, before doing so, make sure the default App Engine service account has at least the Cloud IAM roles/storage.objectCreator role, or otherwise the operation might fail with a permission error. The default App Engine service account has a form of YOUR_PROJECT_ID#appspot.gserviceaccount.com.
If you wish to execute exports on different tables,
datasets and buckets for each execution, but essentially employing the same Cloud Function, you can use the HTTP POST method
instead, and configure a Body containing said parameters as data, which
would be passed on to the Cloud Function - although, that would imply doing
some small changes in its code.
Lastly, when the job is created, you can use the Cloud Function's returned job ID and the bq CLI to view the status of the export job with bq show -j <job_id>.
Not sure if this was in GA when this question was asked, but at least now there is an option to run an export to Cloud Storage via a regular SQL query. See the SQL tab in Exporting table data.
Example:
EXPORT DATA
OPTIONS (
uri = 'gs://bucket/folder/*.csv',
format = 'CSV',
overwrite = true,
header = true,
field_delimiter = ';')
AS (
SELECT field1, field2
FROM mydataset.table1
ORDER BY field1
);
This could as well be trivially setup via a Scheduled Query if you need a periodic export. And, of course, you need to make sure the user or service account running this has permissions to read the source datasets and tables and to write to the destination bucket.
Hopefully this is useful for other peeps visiting this question if not for OP :)
You have an alternative to the second part of the Maxim answer. The code for extracting the table and store it into Cloud Storage should work.
But, when you schedule a query, you can also define a PubSub topic where the BigQuery scheduler will post a message when the job is over. Thereby, the scheduler set up, as described by Maxim is optional and you can simply plug the function to the PubSub notification.
Before performing the extraction, don't forget to check the error status of the pubsub notification. You have also a lot of information about the scheduled query; useful is you want to perform more checks or if you want to generalize the function.
So, another point about the SFTP transfert. I open sourced a projet for querying BigQuery, build a CSV file and transfert this file to FTP server (sFTP and FTPs aren't supported, because my previous company only used FTP protocol!). If your file is smaller than 1.5Gb, I can update my project for adding the SFTP support is you want to use this. Let me know

Importing data from Excel sheet to DynamoDB table

I am having a problem importing data from Excel sheet to a Amazon DynamoDB table. I have the Excel sheet in an Amazon S3 bucket and I want to import data from this sheet to a table in DynamoDB.
Currently I am following Import and Export DynamoDB Data Using AWS Data Pipeline but my pipeline is not working normally.
It gives me WAITING_FOR_RUNNER status and after sometime the status changed to CANCELED. Please suggest what I am doing wrong or is there any other way to import data from an Excel sheet to a DynamoDB table?
The potential reasons are as follows:-
Reason 1:
If your pipeline is in the SCHEDULED state and one or more tasks
appear stuck in the WAITING_FOR_RUNNER state, ensure that you set a
valid value for either the runsOn or workerGroup fields for those
tasks. If both values are empty or missing, the task cannot start
because there is no association between the task and a worker to
perform the tasks. In this situation, you've defined work but haven't
defined what computer will do that work. If applicable, verify that
the workerGroup value assigned to the pipeline component is exactly
the same name and case as the workerGroup value that you configured
for Task Runner.
Reason 2:-
Another potential cause of this problem is that the endpoint and
access key provided to Task Runner is not the same as the AWS Data
Pipeline console or the computer where the AWS Data Pipeline CLI tools
are installed. You might have created new pipelines with no visible
errors, but Task Runner polls the wrong location due to the difference
in credentials, or polls the correct location with insufficient
permissions to identify and run the work specified by the pipeline
definition.

Access Celery's subprocess stdout and stderr in my Django app

I put Celery in my Django app so that the two other python programs can process the input from my Django app via doing subprocess method.
My question is how do I access the output from the subprocess? Back then when I made just a python program, I access the log files (output from the two apps) via stdout and stderr. Is this the same when I use Celery in Django? Is the value of CELERY_RESULT_BACKEND (if I should assign my Django app's db here) affected by the log files?
So far what I've done is:
Access the two apps via subprocess in my tasks.py
I assigned my broker's db, Redis, as my db for now for CELERY_RESULT_BACKEND. My plan is to get the log files and then save them to my Django app's db so that I can just access that db.
Can you offer some help?
Typically, you only care about the task result, which is the return value of the celery task, and that is stored in your result_backend for at least result_expires time (usually 1 day). So, to the extent that you want to access any particular task's result, you can just do so using the task ID.

Using celery beat as a scheduler for irregular intervals?

I have a single django application that allows the user to create multiple distinct blogs. Each blog needs to collect model data (e.g. number of visits, clicks, etc.) hourly/daily/weekly etc. and the interval at which data is collected may be different between blogs. Additionally, at some point in time, the users may want to change the frequency of data collection e.g. from weekly to daily on the user interface.
Looking into Periodic Tasks from the official documentation, it appears that I would have to 'hardcode' the interval values into the settings file and I can only specify the interval once e.g.
from celery.schedules import crontab
CELERYBEAT_SCHEDULE = {
# Executes every Monday morning at 7:30 A.M
'add-every-monday-morning': {
'task': 'tasks.add',
'schedule': crontab(hour=7, minute=30, day_of_week=1),
'args': (16, 16),
},
}
How do I go about this or is it even possible for celery to schedule multiple tasks of the same kind at different intervals AND change the values through the user interface (via AJAX)?
As noted by #devxplorer, django-celery provides a database backend. You could either use this to manage tasks via the Django admin, programmatically, or expose the model through an API.
from djcelery.models import PeriodicTask
PeriodicTask(
name="My First Task",
...
).create()
all_tasks = PeriodicTask.objects.all()
...
Then starting the beat process with
$ celery -A proj beat -S djcelery.schedulers.DatabaseScheduler