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Hi <@U06RKAMK0UC> can you please provide basic fly...
# ask-ai
a
Hi @ancient-wolf-19325 can you please provide basic flyte workflow in podspec and don't use pod template
j
Reasoning Complete! 🤖 🔍 Searched knowledge base: I'll look up the latest information on how to define a basic Flyte workflow using podspec directly, so I can give you a clear and accurate example. • Searching over 10 data sources from the following: File, Github File, Github Issue, Web • Found 56 documents that could be relevant from the following data sources: Github File, Github Issue, Github Pull Request, Web Content. • Filtered down to the top 30 most relevant documents. ✍️ Generated answer: I've found a straightforward example of how to create a Flyte workflow using a PodSpec directly, without relying on pod templates. I'm ready to share the code and explanation with you.
A basic Flyte workflow can be defined using a custom Kubernetes PodSpec directly in the task decorator via the 
task_config
argument, without using a PodTemplate. This is done using the Flytekit Pod plugin, which allows you to specify the full PodSpec for the task. Here’s a minimal example:
Copy code
from flytekit import task, workflow
from flytekitplugins.pod import Pod
from kubernetes.client.models import V1PodSpec, V1Container

@task(
    task_config=Pod(
        pod_spec=V1PodSpec(
            containers=[
                V1Container(
                    name="primary",
                    image="<http://ghcr.io/flyteorg/flytekit:py3.11-latest|ghcr.io/flyteorg/flytekit:py3.11-latest>",
                    command=["python", "-c", "print('Hello from custom pod!')"],
                )
            ]
        )
    )
)
def pod_task() -> str:
    return "Hello from pod task!"

@workflow
def pod_workflow() -> str:
    return pod_task()
This approach uses the Pod plugin and does not require a PodTemplate. For more details, see the Flytekit Kubernetes Pod Plugin README and Flytesnacks pod example. Would you like a step-by-step explanation or more advanced examples? Sources: - Flytesnacks pod example - Flytekit Kubernetes Pod Plugin README 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.
a
from flytekitplugins.pod import Pod ModuleNotFoundError: No module named 'flytekitplugins' Message: ModuleNotFoundError: No module named 'flytekitplugins' i am getting above error @ancient-wolf-19325
j
Reasoning Complete! 🤖 🔍 Searched knowledge base: I'll look up the latest information on how to install and import the Flytekit Pod plugin, so I can help you resolve the ModuleNotFoundError. • Searching over 10 data sources from the following: File, Github File, Github Issue, Web • Found 59 documents that could be relevant from the following data sources: Github File, Github Issue. • Filtered down to the top 30 most relevant documents. ✍️ Generated answer: I've found the cause of your error and the steps to resolve it. I'm ready to provide you with a clear solution.
You need to install the Flytekit Pod plugin to use 
from flytekitplugins.pod import Pod
. Run:
Copy code
pip install flytekitplugins-pod
This will add the required module. See the Flytekit Kubernetes Pod Plugin README and Flytesnacks pod README for reference. Would you like more troubleshooting steps? Sources: - Flytekit Kubernetes Pod Plugin README - Flytesnacks pod README 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.
a
import time from flytekit import task, workflow from flytekitplugins.pod import Pod from kubernetes.client.models import V1PodSpec, V1Container @task( task_config=Pod( primary_container_name="primary", pod_spec=V1PodSpec( containers=[ V1Container( name="second", image="ubuntu:latest", command=["/bin/bash"], args=[ "-c", """sleep 100 && echo sleep is executed && touch /dev/shm/ended """ ] ), # V1Container( # name="third", # image="nginx:latest", # command=["/bin/sh", "-c"], # args=["echo 100 && sleep 200 && echo 100 completed"], # ) ] # init_containers=[ # V1Container( # name="init-base", # image="ubuntu:20.04", # command=["/bin/sh", "-c"], # args=["echo 'Init container running...'"], # security_context=V1SecurityContext(privileged=True), # ) # ], ) ) ) def facil_pod_task() -> str: print('sleep is executing') time.sleep(10) return "Hello from pod task!" @workflow def facil_pod_wf() -> str: return facil_pod_task() why second container is not executing sleep it is exiting with in a seconds what is the reason? @ancient-wolf-19325
j
Reasoning Complete! 🤖 🔍 Searched knowledge base: I'll look up information about how Flyte handles multiple containers in a PodSpec and any known issues with secondary containers, so I can explain why your 'second' container isn't running as expected. • Searching over 10 data sources from the following: File, Github File, Github Issue, Web • Found 56 documents that could be relevant from the following data sources: Github File, Github Issue, Web Content. • Filtered down to the top 30 most relevant documents. ✍️ Generated answer: I've reviewed your code and the typical behavior of Flyte's Pod plugin. The reason your 'second' container exits immediately is likely due to a mismatch between the primary_container_name and the actual container names in your PodSpec, as well as possible issues with how the command and args are passed to the container. I'll explain the details and how to fix it.
It seems likely that the second container (
name="second"
) is exiting immediately because it is not the primary container, and Flyte only injects your Python code into the primary container. The primary container is the one Flyte manages and runs your task logic in; other containers (sidecars) run independently and do not execute the Flyte task code. In your example, you set 
primary_container_name="primary"
, but your only defined container is named 
"second"
, so Flyte will auto-inject a default primary container and your 
"second"
container will not execute your intended logic as the main task. To ensure your custom container runs as the primary, set its name to 
"primary"
and set 
primary_container_name="primary"
. Also, make sure your command and args are correct for the shell you are using. For more, see the Flytesnacks pod example and Flytekit Kubernetes Pod Plugin README. Would you like a step-by-step correction or a working code sample? Sources: - Flytesnacks pod example - Flytekit Kubernetes Pod Plugin README 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.
a
why sleep is not executing in secondary container? import time from pathlib import Path from typing import List from flytekit import ImageSpec, Resources, TaskMetadata, dynamic, map_task, task, workflow from flytekitplugins.pod import Pod from kubernetes.client.models import ( V1Container, V1EmptyDirVolumeSource, V1PodSpec, V1ResourceRequirements, V1Volume, V1VolumeMount, ) image_spec = ImageSpec(registry="ghcr.io/flyteorg", packages=["flytekitplugins-pod"]) _SHARED_DATA_PATH = "/data/message.txt" # %% [markdown] # We define a pod spec with two containers. # While pod tasks generally allow you to customize Kubernetes container attributes, you can still use Flyte directives to specify resources and the image. # Unless you specify the 
container_image
task attribute, the default image built for Flyte tasks will be used. # %% @task( task_config=Pod( pod_spec=V1PodSpec( containers=[ V1Container( name="primary", resources=V1ResourceRequirements( requests={"cpu": "1", "memory": "100Mi"}, limits={"cpu": "1", "memory": "100Mi"}, ), volume_mounts=[ V1VolumeMount( name="shared-data", mount_path="/data", ) ], ), V1Container( name="secondary", image="alpine", command=["/bin/sh"], args=[ "-c", "echo hello", "sleep 100", "echo hi pod world > {}".format(_SHARED_DATA_PATH), ], resources=V1ResourceRequirements( requests={"cpu": "1", "memory": "100Mi"}, limits={"cpu": "1", "memory": "100Mi"}, ), volume_mounts=[ V1VolumeMount( name="shared-data", mount_path="/data", ) ], ), ], volumes=[ V1Volume( name="shared-data", empty_dir=V1EmptyDirVolumeSource(medium="Memory"), ) ], ), ), requests=Resources( mem="1G", ), container_image=image_spec, ) def multiple_containers_pod_task() -> str: # The code defined in this task will get injected into the primary container. while not Path(_SHARED_DATA_PATH).is_file(): time.sleep(5) with open(_SHARED_DATA_PATH, "r") as shared_message_file: return shared_message_file.read() @workflow def multiple_containers_pod_workflow() -> str: txt = multiple_containers_pod_task() return txt @ancient-wolf-19325
j
Reasoning Complete! 🤖 🔍 Searched knowledge base: I'll look up official documentation and known issues about how commands and arguments are handled in multi-container Flyte Pod tasks, especially for secondary containers, to explain why your 'sleep' command isn't running as expected. • Searching over 10 data sources from the following: File, Github File, Github Issue, Web • Found 55 documents that could be relevant from the following data sources: Github File, Github Issue, Github Pull Request, Web Content. • Filtered down to the top 30 most relevant documents. ✍️ Generated answer: I've found the reason your 'sleep' command isn't running in the secondary container: the way the command and args are specified causes only the first command ('echo hello') to run, and the rest are ignored. I'll explain how to fix this.
The 
sleep 100
in your secondary container is not executing because each string in the 
args
list is treated as a separate argument, not as a single shell command. In Kubernetes, when you use 
command=["/bin/sh"]
and 
args=["-c", ...]
, the next argument should be a single string containing the entire shell script. Your current code splits the commands into separate arguments, so only the first (
echo hello
) is executed and the rest are ignored. To fix this, combine your shell commands into a single string in the 
args
list:
Copy code
args=[
    "-c",
    "echo hello && sleep 100 && echo hi pod world > {}".format(_SHARED_DATA_PATH),
],
See the Flytesnacks pod example for correct usage. Would you like a full corrected code sample? Sources: - Flytesnacks pod example 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.
a
Thanks, above one is worked below one is still facing problem import time from pathlib import Path from typing import List from flytekit import ImageSpec, Resources, TaskMetadata, dynamic, map_task, task, workflow from flytekitplugins.pod import Pod from kubernetes.client.models import ( V1Container, V1EmptyDirVolumeSource, V1PodSpec, V1ResourceRequirements, V1Volume, V1VolumeMount, ) image_spec = ImageSpec(registry="ghcr.io/flyteorg", packages=["flytekitplugins-pod"]) @task( container_image=image_spec, task_config=Pod( pod_spec=V1PodSpec( containers=[ V1Container( name="primary", ), V1Container( name="second", image="ubuntu:latest", command=["/bin/bash"], args=[ "-c", "sleep 100 && echo sleep is executed && touch /dev/shm/ended" ] ), ] ) ) ) def facil_pod_task() -> str: print('sleep is executing') time.sleep(10) return "Hello from pod task!" @workflow def facil_pod_wf() -> str: return facil_pod_task() @ancient-wolf-19325
j
Reasoning Complete! 🤖 🔍 Searched knowledge base: I'll look up Flyte documentation and known issues about using multiple containers in a PodSpec, especially with a minimal 'primary' container, to find out why your secondary container isn't working as expected. • Searching over 10 data sources from the following: File, Github File, Github Issue, Web • Found 40 documents that could be relevant from the following data sources: Github File, Github Issue. • Filtered down to the top 30 most relevant documents. ✍️ Generated answer: I've reviewed your code and the way Flyte handles multi-container PodSpecs. I can now explain why your 'second' container's command isn't running as expected and how to fix it.
It seems likely that the 
"second"
container is not running your 
sleep
command because only the 
"primary"
container is managed by Flyte and receives the injected task code. If you do not specify an 
image
for the 
"primary"
container, Flyte will use the default image, and your 
"second"
container will run independently. However, if the 
"primary"
container exits quickly (which it does, since it only runs the Flyte task), the pod may terminate before the 
"second"
container finishes. To ensure the 
"second"
container runs as expected, you should: - Place your logic in the 
"primary"
container, or - Make the 
"primary"
container wait (e.g., with a sleep) so the pod does not exit before the 
"second"
container completes. For more, see the Flytesnacks pod example. Would you like a code sample that ensures both containers run as intended? Sources: - Flytesnacks pod example 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.
a
yes, please provide @ancient-wolf-19325
j
Reasoning Complete! 🤖 🔍 Searched knowledge base: I'll look up official Flyte examples and best practices for running both containers in a multi-container PodSpec, so I can provide you with a working code sample. • Searching over 10 data sources from the following: File, Github File, Github Issue, Web • Found 53 documents that could be relevant from the following data sources: Github File, Github Issue, Web Content. • Filtered down to the top 30 most relevant documents. ✍️ Generated answer: I've gathered all the necessary information and can now provide you with a working code sample and explanation for running both containers in a Flyte PodSpec, ensuring the secondary container completes its work.
Certainly! Here’s a code sample that ensures both containers run as intended: the 
"primary"
container waits for the 
"second"
container to finish by checking for a file created by the 
"second"
container. This pattern is demonstrated in the Flytesnacks pod example:
Copy code
import time
from pathlib import Path
from flytekit import task, workflow
from flytekitplugins.pod import Pod
from kubernetes.client.models import (
    V1Container,
    V1EmptyDirVolumeSource,
    V1PodSpec,
    V1Volume,
    V1VolumeMount,
    V1ResourceRequirements,
)

_SHARED_DATA_PATH = "/data/ended.txt"

@task(
    task_config=Pod(
        pod_spec=V1PodSpec(
            containers=[
                V1Container(
                    name="primary",
                    volume_mounts=[
                        V1VolumeMount(
                            name="shared-data",
                            mount_path="/data",
                        )
                    ],
                ),
                V1Container(
                    name="second",
                    image="ubuntu:latest",
                    command=["/bin/bash"],
                    args=[
                        "-c",
                        f"sleep 10 && echo done > {_SHARED_DATA_PATH}"
                    ],
                    volume_mounts=[
                        V1VolumeMount(
                            name="shared-data",
                            mount_path="/data",
                        )
                    ],
                    resources=V1ResourceRequirements(
                        requests={"cpu": "100m", "memory": "128Mi"},
                        limits={"cpu": "200m", "memory": "256Mi"},
                    ),
                ),
            ],
            volumes=[
                V1Volume(
                    name="shared-data",
                    empty_dir=V1EmptyDirVolumeSource(medium="Memory"),
                )
            ],
        )
    )
)
def facil_pod_task() -> str:
    # Wait for the "second" container to create the file
    while not Path(_SHARED_DATA_PATH).is_file():
        time.sleep(2)
    with open(_SHARED_DATA_PATH, "r") as f:
        return f"Second container says: {f.read().strip()}"

@workflow
def facil_pod_wf() -> str:
    return facil_pod_task()
This ensures the 
"primary"
container waits for the 
"second"
container to finish its work before the pod exits. Sources: - Flytesnacks pod example 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.
a
ok, as per above code, primary container you didn't given any arguments or commands but given a volume_mount to that container now, you are giving some python commands in the function this is logic you build inorder to execute all the containers? @ancient-wolf-19325
j
Reasoning Complete! 🤖 🔍 Searched knowledge base: I'll look up official Flyte documentation to explain how Python code is injected and executed in the primary container, even when no command is set, and how this approach enables coordination with other containers in the pod. • Searching over 10 data sources from the following: File, Github File, Github Issue, Web • Found 50 documents that could be relevant from the following data sources: Github File, Github Issue, Github Pull Request, Web Content. • Filtered down to the top 30 most relevant documents. ✍️ Generated answer: I have all the information needed to explain how Flyte injects your Python code into the primary container and how the volume mount enables coordination between containers. I'll provide a clear answer now.
Yes, that's correct. In Flyte, the code inside the Python 
@task
function is injected and executed in the primary container. You do not need to specify a 
command
or 
args
for the primary container—Flyte automatically runs your Python logic there. The 
volume_mount
allows the primary container to access files written by the secondary container, enabling inter-container communication (e.g., waiting for a file to appear). This pattern is the recommended way to coordinate work between containers in a Flyte pod task: the primary container runs the Flyte task code, while sidecar containers perform supporting actions, and shared volumes are used for communication. See the Flytesnacks pod example for more details. Would you like a deeper explanation of how Flyte injects and runs code in the primary container? Sources: - Flytesnacks pod example 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.
a
@ancient-wolf-19325 update this primary which it is checking for container_ended file in the data directory created by second container # from flytekit import task, workflow # from kubernetes.client import V1PodSpec, V1Container, V1LocalObjectReference, V1SecurityContext, V1ResourceRequirements # # Define PodSpec # facil_pod_spec = V1PodSpec( # #image_pull_secrets=[V1LocalObjectReference(name="my-docker-cred")], # restart_policy="OnFailure", # service_account_name="default", # containers=[ # V1Container( # name="primary", # image="ubuntu:20.04", # command=["/bin/sh", "-c"], # args=[ # """ # until [ -f /dev/shm/recompute_ended ]; do # sleep 1 # done # exit # """ # ], # image_pull_policy="IfNotPresent", # resources=V1ResourceRequirements( # requests={"cpu": "500m", "memory": "512Mi"}, # limits={"cpu": "1", "memory": "1Gi"}, # ), # ), # V1Container( # name="secondary", # image="python:3.9", # command=["python", "-c"], # args=["print('Hello from inside Pod!')"], # image_pull_policy="IfNotPresent", # resources=V1ResourceRequirements( # requests={"cpu": "500m", "memory": "512Mi"}, # limits={"cpu": "1", "memory": "1Gi"}, # ), # ), # ], # init_containers=[ # V1Container( # name="init-base", # image="ubuntu:20.04", # command=["/bin/sh", "-c"], # args=["echo 'Init container running...'"], # security_context=V1SecurityContext(privileged=True), # ) # ], # ) # # Attach PodSpec to Flyte task # @task(pod_spec=facil_pod_spec, primary_container_name="secondary") # def facil_pod_task() -> str: # return "✅ Pod ran successfully!" # # Workflow # @workflow # def facil_pod_wf() -> str: # return facil_pod_task() import time from pathlib import Path from typing import List from flytekit import ImageSpec, Resources, TaskMetadata, dynamic, map_task, task, workflow from flytekitplugins.pod import Pod from kubernetes.client.models import ( V1Container, V1EmptyDirVolumeSource, V1PodSpec, V1ResourceRequirements, V1Volume, V1VolumeMount, ) image_spec = ImageSpec(registry="ghcr.io/flyteorg", packages=["flytekitplugins-pod"]) @task( container_image=image_spec, task_config=Pod( pod_spec=V1PodSpec( containers=[ V1Container( name="primary", volume_mounts=[ V1VolumeMount( name="shared-data", mount_path="/data", ) ], ), V1Container( name="second", image="ubuntu:latest", command=["/bin/bash"], args=[ "-c", "sleep 100 && echo sleep is executed && touch /dev/shm/ended" ] ), ], volumes=[ V1Volume( name="shared-data", empty_dir=V1EmptyDirVolumeSource(medium="Memory"), ) ], ) ) ) def facil_pod_task() -> str: print('sleep is executing') time.sleep(10) return "Hello from pod task!" @workflow def facil_pod_wf() -> str: return facil_pod_task()
j
Reasoning Complete! 🤖 🔍 Searched knowledge base: I'll look up the best way to update your primary container so it waits for a file in the shared /data directory created by the second container, ensuring both containers coordinate correctly. • Searching over 10 data sources from the following: File, Github File, Github Issue, Web • Found 48 documents that could be relevant from the following data sources: Github File, Github Issue, Github Pull Request, Web Content. • Filtered down to the top 30 most relevant documents. ✍️ Generated answer: I have all the information needed to show you how to update your primary container so it waits for a file created by the secondary container in a shared data directory. I'll provide a clear code example and explanation.
To update your Flyte task so that the primary container waits for a file (e.g., 
container_ended
) created by the second container in the 
/data
directory, you should: 1. Mount a shared volume (
/data
) in both containers. 2. In the second container, write the file 
/data/container_ended
after your logic. 3. In the Flyte task (executed in the primary container), poll for the existence of 
/data/container_ended
before returning. Here’s the updated code:
Copy code
import time
from pathlib import Path
from flytekit import task, workflow
from flytekitplugins.pod import Pod
from kubernetes.client.models import (
    V1Container,
    V1EmptyDirVolumeSource,
    V1PodSpec,
    V1Volume,
    V1VolumeMount,
)

_SHARED_DATA_PATH = "/data/container_ended"

@task(
    task_config=Pod(
        pod_spec=V1PodSpec(
            containers=[
                V1Container(
                    name="primary",
                    volume_mounts=[
                        V1VolumeMount(
                            name="shared-data",
                            mount_path="/data",
                        )
                    ],
                ),
                V1Container(
                    name="second",
                    image="ubuntu:latest",
                    command=["/bin/bash"],
                    args=[
                        "-c",
                        f"sleep 10 && echo done > {_SHARED_DATA_PATH}"
                    ],
                    volume_mounts=[
                        V1VolumeMount(
                            name="shared-data",
                            mount_path="/data",
                        )
                    ],
                ),
            ],
            volumes=[
                V1Volume(
                    name="shared-data",
                    empty_dir=V1EmptyDirVolumeSource(medium="Memory"),
                )
            ],
        )
    )
)
def facil_pod_task() -> str:
    # Wait for the second container to create the file
    while not Path(_SHARED_DATA_PATH).is_file():
        time.sleep(2)
    with open(_SHARED_DATA_PATH, "r") as f:
        return f"Second container says: {f.read().strip()}"

@workflow
def facil_pod_wf() -> str:
    return facil_pod_task()
This ensures the primary container waits for the file created by the second container in the shared 
/data
directory, as shown in the Flytesnacks pod example. Sources: - Flytesnacks pod example 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.
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