Scheduled a cron job to hit empty endpoints just to keep the instance running. How do I check the instance has been running for how long just to make sure it's the same instance that has been running since start.
Got it, so in Instances menu under App Engine it shows information related to the instance which includes Start Time.
You have three ways to check how much time the instance has been running.
The first one is through the Instances menu, as you said.
The second one would be through the Rest API. In the response you can see the start time as one of the json attributes.
The third one would be through the gcloud command line console with the command:
gcloud app instances describe --service=SERVICE --version=VERSION NAME
That will return you similar information as in the API request that also includes the start time.
Related
I have been racking my brains on this for a few weeks now, trying different variations from Google Cloud service offerings but can't seem to find the proper one.
I have a python script with dependencies etc, that I have containerized, pushed, and deploy to GCR.
The script is a bot that connects to an external websocket receiving signals perpetually to then do other processing via API against another external service.
What would be the best service offering from Google Cloud to run this?
So far, I've tried:
GCR Web Service - requires listening service (:8080) which I do not provide in this use case, and, it scales down your service when there is no traffic so no go.
GCR Job Service - Seems like the next ideal option (no HTTP port requirement) - however, since the script (my entry point), upon launch, doesn't 'return' unless it quits, the service launch just allows it to run for a minute or so, until the jobs API declares it as 'failed' - basically, it is launching it via my entry point which just executes the script as if it was running locally and my script isn't meant to return anything.
To try and get around this, I went the google's recommended way and built a main.py with they standard boilerplate, and built it as a wrapper to act as a launcher for the actual script. I did this via a simple subprocess.Popen using their sample main.py as shown below.
main.py
import json
import os
import sys
import subprocess
# Retrieve Job-defined env vars
TASK_INDEX = os.getenv("CLOUD_RUN_TASK_INDEX", 0)
TASK_ATTEMPT = os.getenv("CLOUD_RUN_TASK_ATTEMPT", 0)
# Define main script
def main():
print(f"Starting Task #{TASK_INDEX}, Attempt #{TASK_ATTEMPT}...")
subprocess.Popen(["python3", "myscript.py"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
print(f"Completed Task #{TASK_INDEX}.")
# Start script
if __name__ == "__main__":
try:
main()
except Exception as err:
message = f"Task #{TASK_INDEX}, " \
+ f"Attempt #{TASK_ATTEMPT} failed: {str(err)}"
print(json.dumps({"message": message, "severity": "ERROR"}))
sys.exit(1) # Retry Job Task by exiting the process
My thinking being, this would allow the job to execute my script and mark the job as completed, while the actual script remains running. Also, since subprocess.Popen sets its stdout and stderr to PIPE, my thinking is it would get caught by the google logging and I would see the output.
The job runs and marks it as succeed, however, I see no indication of the actual script executing anywhere.
I had similar issue with Google Cloud functions. Jobs seemed like an ideal option since I can run on their scheduler to make sure it is launching after saying, every hour (my script uses a lock file so it doesn't run again if running).
Am I just missing the point on how these cloud services run?
Do offerings like google cloud run jobs/functions, etc meant to execute jobs that return and quit until launched again by however scheduled?
Do I need to consider Google Computing engine as an option for this use case that is, a full running VM instead of stateless/serverless options?
I am trying to use this in a containerized, scalable as needed, fashion to both make my project portable and minimize costs as much as possible given the always running nature of the job.
Lastly, I know services like pythonanywhere as I am sure others, make this kinda stuff easier, but I would like to learn how to do this via standard cloud offerings like GCR, AWS, etc.
thanks for any insight / advice!
Cloud Run best fit is for HTTP Rest APIs serving (stateless services). There are also Jobs in beta.
One of the top feature of Run is that it scales to 0, when there are not requests to your service (your service instance gets totally destroyed).
If your bot needs to stay alive "for ever", Run is not for you... (Even if you can configure Run to keep at least one instance live).
I would consider instead AppEngine or Compute.
I successfully deployed a twitter screenshot bot on Google App Engine.
This is my first time deploying.
First thing I noticed was that the app didn't start running until I clicked the link.
When I did, the app worked successfully (replied to tweets with screenshots) as long as the tab was loading and open.
When I closed the tab, the bot stopped working.
Also, in the cloud shell log, I saw:
Handling signal: term
[INFO] Worker exiting (pid 18)
This behaviour surprises me as I expect it to keep running on google server indefinitely.
My bot works by streaming with Twitter api. Also the "worker exiting" line above surprises me.
Here is the relevant code:
def get_stream(set):
global servecount
with requests.get(f"https://api.twitter.com/2/tweets/search/stream?tweet.fields=id,author_id&user.fields=id,username&expansions=author_id,referenced_tweets.id", auth=bearer_oauth, stream=True) as response:
print(response.status_code)
if response.status_code == 429:
print(f"returned code 429, waiting for 60 seconds to try again")
print(response.text)
time.sleep(60)
return
if response.status_code != 200:
raise Exception(
f"Cannot get stream (HTTP {response.status_code}): {response.text}"
)
for response_line in response.iter_lines():
if response_line:
json_response = json.loads(response_line)
print(json.dumps(json_response, indent=4))
if json_response['data']['referenced_tweets'][0]['type'] != "replied_to":
print(f"that was a {json_response['data']['referenced_tweets'][0]['type']} tweet not a reply. Moving on.")
continue
uname = json_response['includes']['users'][0]['username']
tid = json_response['data']['id']
reply_tid = json_response['includes']['tweets'][0]['id']
or_uid = json_response['includes']['tweets'][0]['author_id']
print(uname, tid, reply_tid, or_uid)
followers = api.get_follower_ids(user_id='1509540822815055881')
uid = int(json_response['data']['author_id'])
if uid not in followers:
try:
client.create_tweet(text=f"{uname}, you need to follow me first :)\nPlease follow and retry. \n\n\nIf there is a problem, please speak with my creator, #JoIyke_", in_reply_to_tweet_id=tid, media_ids=[mid])
except:
print("tweet failed")
continue
mid = getmedia(uname, reply_tid)
#try:
client.create_tweet(text=f"{uname}, here is your screenshot: \n\n\nIf there is a problem, please speak with my creator, #JoIyke_", in_reply_to_tweet_id=tid, media_ids=[mid])
#print(f"served {servecount} users with screenshot")
#servecount += 1
#except:
# print("tweet failed")
editlogger()
def main():
servecount, tries = 1, 1
rules = get_rules()
delete = delete_all_rules(rules)
set = set_rules(delete)
while True:
print(f"starting try: {tries}")
get_stream(set)
tries += 1
If this is important, my app.yaml file has only one line:
runtime: python38
and I deployed the app from cloud shell with gcloud app deploy app.yaml
What can I do?
I have searched and can't seem to find a solution. Also, this is my first time deploying an app sucessfully.
Thank you.
Google App Engine works on demand i.e. when it receives an HTTP(s) request.
Neither Warmup requests nor min_instances > 0 will meet your needs. A warmup tries to 'start up' an instance before your requests come in. A min_instance > 0 simply says not to kill the instance but you still need an http request to invoke the service (which is what you did by opening a browser tab and entering your Apps url).
You may ask - since you've 'started up' the instance by opening a browser tab, why doesn't it keep running afterwards? The answer is that every request to a Google App Engine (Standard) app must complete within 1 - 10 minutes (depending on the type of scaling) your App is using (see documentation). For Google App Engine Flexible, the timeout goes up to 60 minutes. This tells you that your service will timeout after at most 10 minutes on GAE standard or 60 minutes on GAE Flexible.
I think the best solution for you on GCP is to use Google Compute Engine (GCE). Spin up a virtual server (pick the lowest configuration so you can stick within the free tier). If you use GCE, it means you spin up a Virtual Machine (VM), deploy your code to it and kick off your code. Your code then runs continuously.
App Engine works on demand, i.e, only will be up if there are requests to the app (this is why when you click on the URL the app works). As well you can set 1 instance to be "running all the time" (min_instances) it will be an anti-pattern for what you want to accomplish and App Engine. Please read How Instances are Managed
Looking at your code you're pulling data every minute from Twitter, so the best option for you is using Cloud Scheduler + Cloud Functions.
Cloud Scheduler will call your Function and it will check if there is data to process, if not the process is terminated. This will help you to save costs because instead of have something running all the time, the function will only work the needed time.
On the other hand I'm not an expert with the Twitter API, but if there is a way that instead of pulling data from Twitter and Twitter calls directly your function it will be better since you can optimize your costs and the function will only run when there is data to process instead of checking every n minutes.
As an advice, first review all the options you have in GCP or the provider you'll use, then choose the best one for your use case. Just selecting one that works with your programming language does not necessarily will work as you expect like in this case.
I've created an application and I'd like to test how well it scales to large numbers of users.
To run my application a user has to go to the homepage, sign in to a Google account, click a button and then upload a video file.
First of all, is this possible to emulate using JMeter? I'm signed into my Google account locally but am not sure whether simulated users will have access to it?
Secondly, I've recorded a session in JMeter doing the actions above and have run the test with 10 simulated users, however, the App Engine dashboard doesn't detect any activity. I've followed the steps mentioned here but obviously with details of my application etc.
Here's a screenshot of the summary report.
Is there anything obvious I might be doing wrong? Am I using JMeter in the correct way to test the application as desired?
Apologies for my JMeter inexperience.
This is not something you will be able to record and replay, my expectation is that your application is protected by OAuth so you will need some token in order to execute your calls.
Not knowing the details of your application implementation it's quite hard to guess what's went wrong, I would recommend
Running your test with 1 user and 1 loop first to ensure that it's doing what it is supposed to be doing by adding View Results Tree listener and inspecting request and response details for each sampler (especially for failed ones).
Once you figure out what's wrong with this particular request - amend JMeter configuration so it would be successful. Repeat until you're happy with the test end-to-end.
Add load only after that and be careful as test might be sensitive to extra users/loops, especially if you're using a single login account (which is not recommended)
References:
How to Handle Correlation in JMeter
How to Run Performance Tests on OAuth Secured Apps with JMeter
I noticed this:
(Note that I deployed this service just 2 days ago and no one know it!!)
The only valid request here is the one to "/extract" at 4:10, because it is correct and it is at the scheduled time (of the cron job).
(You can also notice that the user agent is "AppEngine")
I created some routing for the "hacking try" paths to reply with a "F*** Y**".
Then I decided to use a dos.yaml file to define a blacklist.
I was taking note of the IPs and I noticed that the IP of the valid request is also used in this request (and probably other "malicious" ones):
I noticed that every execution of the my scheduled "cron job" (automated one or using "Run now") has a different IP. Also all the malicious requests have different IPs but you can see that some of them are executed programmatically:
How is it possible?
My explanation is that Google Cloud Platform is hosting a lot of malicious services.
Also, the documentation says that cron jobs are issued by the IP 0.1.0.1.
Someone can explain me this unexpected behavior or where is the fault in my argument?
Alex
I planning to create a NodeJS program, that work 24/7, that ping and make requests to an external server (outside of google cloud) every minute. Just to see that it the external services are are live.
If there is any error it will notify me by SMS & Email.
I don't need any front-end for this app, and no one needs to connect to it. Just simple NodeJS program.
The monitoring and configuration will be by texts files.
Now the questions:
It looks like it will cost me just $1.64. It sounds very cheap. Am I missing something?
It needs to work around the clock, I will request it to start it once, and it need to continue working, (by using setInterval). Is it will be aborted?
What it is exactly mean buy 1 instance. What an instance can do? Only respond to one request or what?
I tried to search in Google: appengine timeout, but didn't found anything that helps.
Free Quota
If you write your application in Python, PHP, Go or Java it can fit in free usage quota:
https://cloud.google.com/appengine/docs/quotas
So there will be absolutely no costs to run it on Google App Engine platform.
There are limit of 657,000 UrlFetch API Calls per day (more than 450 calls per minute in 24/7 mode) for free apps. 4GB traffic may also be sufficient for this kind of work.
Keep in mind there is no SMS sending services provided by Google App Engine and you will need to spend additional UrlFetch API calls to use external SMS services.
Email sending is also limited to 100 Emails per day (or 5000 Emails to admin address), so try not so send repeated notifications about same monitored server every minute, or you'll deplete your Email quote in 1.5 hours.
Scheduled Tasks
There is no way to run single process indefinitely without interruption on App Engine. But you don't have to!
You'll need to encapsulate all the work you're planning to execute in every iteration into single task and then schedule it to run every minute with Cron. See this documentation for Python: https://cloud.google.com/appengine/docs/python/config/cron
It is recommended to have some configuration page where you can set some internal configuration or see monitoring statistics, at least manage flag to temporarily pause tasks execution without redeploying your app.