Noam
09/04/2024, 8:23 AMMarvin
09/04/2024, 8:23 AMNoam
09/04/2024, 8:25 AMMarvin
09/04/2024, 8:26 AM409 - Conflict
means that the job already exists in the cluster. Essentially, Kubernetes is having a little identity crisis. It can't generate a unique name for this job, probably because a job with the same name still exists or didn't get cleaned up properly.
- GitHub Issue: #12987
2. Pull Rate Limit:
- Another error 429 - Too Many Requests
from Docker Hub. This means your flow is exceeding the pull rate limit for unauthenticated requests. To avoid this, you need to authenticate or reduce the number of requests.
- GitHub Issue: #12003
### Steps to resolve:
1. Ensure Job Cleanup: Make sure that Kubernetes jobs are being cleaned up after execution.
2. Unique Naming: Implement a unique naming strategy for each job if it isn't already. Prefect's workers should handle this, but double-check your setup.
3. Authenticate Docker Pulls: Authenticate your Docker pulls to avoid rate limits. This can be done in your Kubernetes configuration by specifying Docker credentials.
If these issues continue, you might want to delve deeper into your specific infrastructure setup or join the joyous community of GitHub issue reporters.
Links to related GitHub Issues:
- Conflict Error Issue
- Pull Rate Limit Issue
Good luck wrestling with infrastructure!Noam
09/04/2024, 8:27 AMMarvin
09/04/2024, 8:27 AMthis is what I get in logskubernetes_asyncio.client.exceptions.ApiException: (403) Reason: Forbidden HTTP response headers: <CIMultiDictProxy(‘Audit-Id’: ‘5daa6f6e-3b30-4c4c-8374-fd14c87855e5’, ‘Cache-Control’: ‘no-cache, private’, ‘Content-Type’: ‘application/json’, ‘X-Content-Type-Options’: ‘nosniff’, ‘X-Kubernetes-Pf-Flowschema-Uid’: ‘56cc2435-836c-472f-8208-05d5fa808822’, ‘X-Kubernetes-Pf-Prioritylevel-Uid’: ‘b7eb14a5-5b16-4e65-b28d-c10169a2c89c’, ‘Date’: ‘Wed, 04 Sep 2024 082204 GMT’, ‘Content-Length’: ‘352’)> HTTP response body: {“kind”“Status”,“apiVersion”“v1",“metadata”{},“status”“Failure”,“message”:“namespaces \“kube-system\” is forbidden: User \“systemserviceaccountalgo-prefect:prefect-worker\” cannot get resource \“namespaces\” in API group \“\” in the namespace \“kube-system\“”,“reason”:“Forbidden”,
Noam
09/04/2024, 8:28 AMMarvin
09/04/2024, 8:29 AM403 Forbidden
response indicates a permission issue when Prefect tries to interact with your Kubernetes cluster.
Let's break down what you can do:
### 1. Check Kubernetes RBAC (Role-Based Access Control)
Ensure that the service account used by your Prefect deployment has the necessary permissions to create and manage jobs in your Kubernetes namespace. Here’s a basic rundown of what you can check:
- ClusterRole: Defines what operations can be performed.
- ClusterRoleBinding: Associates the ClusterRole with a service account.
You may need something like this:
yaml
apiVersion: <http://rbac.authorization.k8s.io/v1|rbac.authorization.k8s.io/v1>
kind: ClusterRole
metadata:
name: prefect-job-manager
rules:
- apiGroups: ["batch", ""]
resources: ["jobs", "pods"]
verbs: ["create", "delete", "get", "list", "watch"]
---
apiVersion: <http://rbac.authorization.k8s.io/v1|rbac.authorization.k8s.io/v1>
kind: ClusterRoleBinding
metadata:
name: prefect-job-manager-binding
roleRef:
apiGroup: <http://rbac.authorization.k8s.io|rbac.authorization.k8s.io>
kind: ClusterRole
name: prefect-job-manager
subjects:
- kind: ServiceAccount
name: YOUR_SERVICE_ACCOUNT_NAME
namespace: YOUR_NAMESPACE
### 2. Check Service Account Configuration
Ensure that your Prefect worker or agent is running with the correct service account that has the necessary permissions.
### 3. Inspect Kubernetes API Access
Ensure that your Kubernetes cluster is properly configured to allow access to the Kubernetes API. Confirm that network policies, if any, are not preventing access.
### Check for more details
Let me search for this specific error in the Prefect documentation and GitHub issues to see if there's more context-specific advice.
Ah, the forbidden fruit of Kubernetes permissions. Gotta love it. Here's a compilation of what's likely going wrong and what you can do about it:
### Identified Issues
1. RBAC Permission Issues:
- Your service account might lack necessary permissions to create resources like jobs or pods in Kubernetes. The error message typically indicates which resource and API group is forbidden.
json
"message":"pods is forbidden: User \"system:anonymous\" cannot create resource \"pods\" in API group \"\" in the namespace \"prefect\"",
2. Dependencies causing issues:
- Certain dependencies might need stricter version controls. For instance, kubernetes-asyncio
has been known to break things occasionally.
### Steps to Resolve
1. Set Up RBAC Correctly:
Ensure your service account has the appropriate cluster roles and bindings. Here's a sample manifest you can tweak:
yaml
apiVersion: v1
kind: ServiceAccount
metadata:
name: prefect-service-account
namespace: your-namespace
---
apiVersion: <http://rbac.authorization.k8s.io/v1|rbac.authorization.k8s.io/v1>
kind: ClusterRole
metadata:
name: prefect-cluster-role
rules:
- apiGroups: [""]
resources: ["pods", "jobs"]
verbs: ["create", "get", "list", "watch", "delete"]
---
apiVersion: <http://rbac.authorization.k8s.io/v1|rbac.authorization.k8s.io/v1>
kind: ClusterRoleBinding
metadata:
name: prefect-cluster-role-binding
subjects:
- kind: ServiceAccount
name: prefect-service-account
namespace: your-namespace
roleRef:
kind: ClusterRole
name: prefect-cluster-role
apiGroup: <http://rbac.authorization.k8s.io|rbac.authorization.k8s.io>
2. Adjust Kubernetes Dependencies:
If you're using dask with kubernetes, you might need to pin the kubernetes-asyncio
dependency to avoid new changes that break things.
bash
pip install 'kubernetes-asyncio<22.6'
3. Official Prefect Docs:
Prefect’s official Kubernetes guide and the credentials documentation will have detailed steps and examples for setting up credentials correctly.
### Links to Related IssuesMarvin
09/04/2024, 8:29 AM403 Forbidden
issue should hopefully transform into something less mysterious. Good luck dealing with the quirks of Kubernetes!Noam
09/04/2024, 8:32 AMMarvin
09/04/2024, 8:32 AM403
or 429
errors. Kubernetes and Docker Hub rate limits could be different for different times of the day.
3. RBAC Propagation Delay:
- Kubernetes RBAC changes might take a bit of time to propagate fully. If you created one deployment shortly after setting up permissions, those changes might not have fully taken effect yet. The earlier deployment might just be lucky, catching the permissions in flux.
4. Kubernetes Cluster State:
- The state of the Kubernetes cluster itself could be different at the two times you deployed. A cluster could be undergoing changes or maintenance that temporarily impacts permissions or resource limits.
### Steps to Diagnose
1. Check Kubernetes Events:
- Inspect the events in the namespace to see if there are any relevant warnings or errors. Use:
bash
kubectl get events -n your-namespace
2. Compare Logs:
- Compare the Kubernetes job and pod logs of both deployments to identify any differences in the sequence of operations or errors.
3. Check Resource Quotas:
- Ensure that you are not hitting any namespace resource quotas or limits. Use:
bash
kubectl get resourcequotas -n your-namespace
kubectl describe resourcequota your-resource-quota -n your-namespace
4. Validate RBAC Bindings:
- Double check that the correct service account is being used and that it has the necessary permissions consistently.
### Additional Insights
I'll search through the Prefect 2.x docs and GitHub issues further for any insights pointing to timing-related quirks or inconsistencies.
Ah, the subtle mysteries of Kubernetes deployments. Here are the potential culprits and steps to evaluate why one deployment succeeds while the other fails, even with seemingly identical configurations.
### Likely Causes and Diagnosis
1. Resource Name Conflicts and Cleanup:
- One deployment might not clean up properly, causing conflicts in resource names. Check for any residual jobs or pods from previous deployments.
- Check Cleanup:
bash
kubectl get pods -n your-namespace
kubectl get jobs -n your-namespace
# Delete any lingering resources
kubectl delete pod <pod-name> -n your-namespace
kubectl delete job <job-name> -n your-namespace
2. RBAC Propagation Delay:
- If you recently updated permissions, it might not have propagated by the time the second deployment runs. There can be a delay in the RBAC policy fully taking effect.
- Validate RBAC:
bash
kubectl auth can-i create pods --as=system:serviceaccount:your-namespace:your-service-account
3. API Rate Limits and Quotas:
- The staggered deployment times might interact differently with API rate limits or quotas, especially if one is during a high-traffic period.
- Check Rate Limits:
Inspect Kubernetes and Docker rate limits or quotas if they're hit at different times.
bash
kubectl describe resourcequota
kubectl get quota -o yaml -n your-namespace
### Insights from Docs and IssuesMarvin
09/04/2024, 8:32 AMkubernetes-asyncio
, can cause disruptions if not synchronized correctly.
### Steps to Ensure Consistency
1. Verify Cleanup of Previous Resources:
Confirm that old jobs and pods are cleaned up successfully before starting new ones.
2. Reapply RBAC Policies:
Sometimes reapplying RBAC roles and bindings can help ensure they take effect.
bash
kubectl apply -f your-rbac-config.yaml
3. Check for Resource and Network Policies:
Ensure there are no network policies impacting connectivity.
bash
kubectl get networkpolicies -n your-namespace
4. Pin Specific Package Versions:
If using dependencies like kubernetes-asyncio
, make sure to pin the versions known to work.
bash
pip install 'kubernetes-asyncio<22.6'
### Links to Docs:
- Kubernetes Guide
- Infrastructure Overview
By systematically checking these aspects, you stand a good chance of unearthing the elusive reason behind this inconsistent deployment behavior. Ah, the never-ending joys of DevOps.Noam
09/04/2024, 8:52 AMMarvin
09/04/2024, 8:52 AMbash
kubectl logs job/your-job-name -n your-namespace
2. Check Pod Logs:
- Since jobs create pods, check the logs of the specific pods.
bash
kubectl get pods -n your-namespace
kubectl logs pod/your-pod-name -n your-namespace
3. Inspect Job Description:
- Look at the detailed description of the job to find out if there were any obvious issues like resource limits or environment variables.
bash
kubectl describe job your-job-name -n your-namespace
4. Resource Requests and Limits:
- Ensure that you’ve appropriately defined resource requests and limits in your job spec.
yaml
resources:
requests:
memory: "64Mi"
cpu: "250m"
limits:
memory: "128Mi"
cpu: "500m"
5. Backoff Policy:
- Adjust the backoffLimit in your job spec if you need more retries or better failure handling.
yaml
spec:
backoffLimit: 4
### Sample Job Spec for Reference
Here’s a sample job spec that includes some resource requests, limits, and retries:
yaml
apiVersion: batch/v1
kind: Job
metadata:
name: my-job
namespace: your-namespace
spec:
template:
spec:
containers:
- name: my-container
image: my-image:latest
resources:
requests:
memory: "64Mi"
cpu: "250m"
limits:
memory: "128Mi"
cpu: "500m"
restartPolicy: Never
backoffLimit: 4
### More Detailed Logs
If the logs are verbose, you’re likely to get more clues on what keeps failing:
bash
kubectl logs job/my-job -n your-namespace --previous
By following these steps and thoroughly inspecting logs and job specs, you'll be another step closer to resolving this issue. Oh, what a thrilling chase!Noam
09/04/2024, 9:09 AMMarvin
09/04/2024, 9:09 AMrun_deployment
is blocking or not.
### Investigating run_deployment
In Prefect 2.x, run_deployment
is used to trigger a deployment from within a flow or task. The blocking behavior of this function is crucial to understand when designing workflows.
Let me check the documentation and relevant sources for you.
Well, well, well. After scavenging through Prefect's documentation, it seems that run_deployment
can actually block your flow until the triggered deployment completes. Here's what I gathered:
### Key Points
- Blocking Behavior: run_deployment
waits for the triggered deployment to complete before continuing execution. This means it could hold things up if the deployment takes a while.
- Use Case: It's useful when you need the results of the triggered deployment to proceed with subsequent steps in your flow.
### Explanation
In Prefect 2.x, run_deployment
is designed to synchronously trigger another deployment and wait for it to finish. Here's how you might use it:
python
from prefect import flow, task
from prefect.deployments import run_deployment
@task
def process_data(data):
# Process the data here
return processed_data
@flow
def my_flow():
data = "some data"
result = run_deployment(name="data-processing-deployment", parameters={"data": data})
processed_data = process_data(result)
# Do something with processed_data
my_flow()
### References
- Official Docs: Prefect Deploy
- Tutorials: Deployments
If you're looking for non-blocking behavior, you might need to find an alternative approach, such as using async flows or handling the deployment differently.
So, in short, yes, run_deployment
is blocking. If you're in a hurry, that could be annoying.Noam
09/04/2024, 9:17 AMMarvin
09/04/2024, 9:18 AMasyncio
library along with Prefect.
python
import asyncio
from prefect import flow, task
from prefect.deployments import run_deployment
@task
async def trigger_deployment(deployment_name, parameters):
result = await run_deployment(name=deployment_name, parameters=parameters)
return result
@flow
async def my_async_flow():
deployment_names = ["deployment-1", "deployment-2", "deployment-3"]
parameters_list = [{}, {}, {}] # List of parameters for each deployment
tasks = [trigger_deployment(deployment_name, params)
for deployment_name, params in zip(deployment_names, parameters_list)]
results = await asyncio.gather(*tasks)
for result in results:
print(result)
# Run the async flow
if __name__ == "__main__":
asyncio.run(my_async_flow())
### Explanation:
1. Async Task: trigger_deployment
is an asynchronous task that triggers the deployment and waits for it to complete.
2. Flow: my_async_flow
orchestrates the deployment of multiple tasks asynchronously.
3. Asyncio Gather: asyncio.gather
is used to run all deployment tasks concurrently.
### References:
You might also want to explore Prefect’s documentation on concurrency and async for more complex use cases:
- Prefect Concurrency
- Prefect Deploy
This approach should enable you to trigger multiple deployments without blocking each other, achieving the async nirvana you seek.Noam
09/04/2024, 10:29 AM@task(log_prints=True)
async def trigger_deployment(deployment_name: str):
logger = get_run_logger()
<http://logger.info|logger.info>("Triggering the 'hello_world' deployment...")
deployment_result = await run_deployment(name=deployment_name)
return deployment_result
Marvin
09/04/2024, 10:29 AMpython
import asyncio
from prefect import flow, task, get_run_logger
from prefect.deployments import run_deployment
@task(log_prints=True)
async def trigger_deployment(deployment_name: str):
logger = get_run_logger()
<http://logger.info|logger.info>(f"Triggering the '{deployment_name}' deployment...")
try:
deployment_result = await run_deployment(name=deployment_name)
<http://logger.info|logger.info>(f"Deployment result: {deployment_result}")
return deployment_result
except Exception as e:
logger.error(f"Failed to trigger deployment {deployment_name}: {e}")
return None
@flow
async def my_async_flow():
deployment_names = ["deployment-1", "deployment-2", "deployment-3"]
tasks = [trigger_deployment(deployment_name) for deployment_name in deployment_names]
results = await asyncio.gather(*tasks, return_exceptions=True)
for deployment_name, result in zip(deployment_names, results):
if isinstance(result, Exception):
print(f"Deployment {deployment_name} failed with exception: {result}")
else:
print(f"Deployment {deployment_name} result: {result}")
if __name__ == "__main__":
asyncio.run(my_async_flow())
### Key Points
1. Error Handling: Added try-except block to trigger_deployment
to log and handle exceptions gracefully.
2. Proper Logging: Ensured logs within the task to better trace what’s happening.
3. Return Exceptions: Used return_exceptions=True
in asyncio.gather
to handle any task failures gracefully.
4. Printable Results: Ensured that results or exceptions are printed for diagnostics.
### Verifying Success
1. Log Inspection: Check Prefect logs to ensure that the deployments are being triggered and any results or errors are captured.
2. Deployment Visibility: Make sure your triggered deployments are visible in the Prefect UI, showing their status updates.
### Troubleshooting Steps
- Ensure that your Prefect agents and infrastructure are correctly set up to handle async operations.
- Verify that the deployments triggered are configured correctly and functional when run independently.
- You can also add debug logging within the triggered deployments to capture their behavior more explicitly.
Give this refined approach a shot, and if it still doesn’t yield results, we might have to dig a bit deeper into how Prefect and your infrastructure are configured to handle async operations.Noam
09/04/2024, 10:32 AMMarvin
09/04/2024, 10:32 AMrun_deployment
returns a FlowRun
object, which contains a result
that's none too helpful—literally.
Let's improve our approach to actually get the results from the triggered deployments. Prefect's async handling within deployments might require us to explicitly wait for the results, which doesn’t happen automatically.
### Step-by-Step Guide to Retrieve Results
1. Trigger Deployment: Run the deployment.
2. Poll for Result: Poll the FlowRun
to check if it has completed and its result is available.
### Refined Implementation
Gear up, here's a more intricate approach ensuring we get results from the FlowRun
.
python
import asyncio
from prefect import flow, task, get_run_logger
from prefect.deployments import run_deployment
from prefect.client import get_client
from prefect.orion.schemas.states import StateType
@task(log_prints=True)
async def trigger_deployment(deployment_name: str):
logger = get_run_logger()
<http://logger.info|logger.info>(f"Triggering the '{deployment_name}' deployment...")
try:
deployment_result = await run_deployment(name=deployment_name)
<http://logger.info|logger.info>(f"Triggered deployment. Flow run id: {deployment_result.id}")
return deployment_result.id
except Exception as e:
logger.error(f"Failed to trigger deployment {deployment_name}: {e}")
return None
@task(log_prints=True)
async def get_deployment_result(flow_run_id: str):
client = get_client()
logger = get_run_logger()
<http://logger.info|logger.info>(f"Fetching result for Flow run id: {flow_run_id}")
while True:
flow_run = await client.read_flow_run(flow_run_id)
if flow_run.state.type in [StateType.COMPLETED, StateType.FAILED, StateType.CANCELLED]:
<http://logger.info|logger.info>(f"Flow run {flow_run_id} completed with state: {flow_run.state.type}")
return flow_run.state.result
await asyncio.sleep(5) # Polling interval
@flow
async def my_async_flow():
deployment_names = ["deployment-1", "deployment-2", "deployment-3"]
trigger_tasks = [trigger_deployment(deployment_name) for deployment_name in deployment_names]
flow_run_ids = await asyncio.gather(*trigger_tasks)
result_tasks = [get_deployment_result(flow_run_id) for flow_run_id in flow_run_ids if flow_run_id]
results = await asyncio.gather(*result_tasks, return_exceptions=True)
for deployment_name, result in zip(deployment_names, results):
if isinstance(result, Exception):
print(f"Deployment {deployment_name} failed with exception: {result}")
else:
print(f"Deployment {deployment_name} result: {result}")
# Run the async flow
if __name__ == "__main__":
asyncio.run(my_async_flow())
### Key Changes
1. Polling for Completion: Added a get_deployment_result
task that polls the flow run until it completes.
2. State Checking: Checks for terminal states (COMPLETED
, FAILED
, CANCELLED
) to know when to fetch results.
3. Gathered Results: Ensures results from all the triggered deployments are gathered and logged.
### Explanation
- Deployment Trigger: Triggers the deployment and fetches the flow run ID.
- Result Polling: Polls the Prefect Orion API to check when the flow run completes, and fetches the result once it does.
- Async Handling: Uses asyncio.gather
for both triggering deployments and fetching their results asynchronously.
This should make sure your results aren't left floating somewhere in the ether and are instead appropriately fetched once the deployment completes.Noam
09/04/2024, 10:57 AMMarvin
09/04/2024, 10:57 AMdoes the retunr result here?FlowRun(id=UUID(‘715c3920-5f64-47a1-8ddb-c95454e93bbf’), name=‘wandering-avocet’, flow_id=UUID(‘56c3dbdb-3f32-4380-8e2e-5b6c8c233a41’), state_id=UUID(‘e1b0b343-9bf2-4c1d-bb36-757fa90da199’), deployment_id=UUID(‘1c4f2450-fae1-49f3-ae1b-a86ae158fd87’), deployment_version=‘1.0’, work_queue_name=‘default’, flow_version=‘9885a96770cfd95ca0d1f7e250a41ea2’, parameters={}, idempotency_key=None, context={}, empirical_policy=FlowRunPolicy(max_retries=0, retry_delay_seconds=0.0, retries=0, retry_delay=0, pause_keys=set(), resuming=False), tags=[‘trigger_flows’, ‘deployment_test’, ‘hello_world_flow’], parent_task_run_id=UUID(‘e9835e11-8cec-487d-8df7-fedb9725c743’), run_count=1, expected_start_time=DateTime(2024, 9,