Joshua Caskie
06/25/2024, 12:36 PMflow.from_source(
source=GitRepository(
url="my/git/repo.git",
branch="develop",
credentials=GitLabCredentials.load("repo-prefect")
),
entrypoint="main.py:main"
).deploy(
name="repo-deploy",
work_pool_name="my-docker-pool",
cron="0 0 * * *",
tags=["dev", "repo"],
build=False,
job_variables={"env": {"EXTRA_PIP_PACKAGES": "pandas"} }
)
Error:
prefect.exceptions.ScriptError: Script at '/var/folders/bv/yzk7hd_d19s1c6n0krxwyr340000gq/T/tmp418livpe/repo-develop/main.py' encountered an exception: ModuleNotFoundError("No module named 'pandas._config'")
Marvin
06/25/2024, 12:36 PMpandas
module not being found. This can be related to several potential issues:
1. Dependencies Not Installed: The Docker image or environment where the flow is executing might not have the pandas
library installed, or it failed to install properly.
2. Misconfigured Environment: The EXTRA_PIP_PACKAGES
environment variable is supposed to install pandas
, but it might not be working as intended.
3. Simultaneous Execution: There are known issues where flows using certain packages, such as dbt
, can encounter ModuleNotFoundError
when run concurrently. While this doesn’t directly mention pandas
, it signals a potential problem with package management in concurrent executions.
Steps to Troubleshoot and Fix:
1. Ensure Dependencies Are Installed: Ensure that the Docker image has pandas
installed. You can add a requirements file or explicitly install it in your Dockerfile.
2. Verify Environment Variable Configuration: Make sure the syntax and method you’re using to set EXTRA_PIP_PACKAGES
is correct and effective.
3. Isolation of Dependencies: Ensure that dependencies are isolated correctly or not interfered with other flows. Use virtual environments if needed.
4. Log Outputs for Debugging:
- Check logs for messages about package installation failure.
- Ensure Python and pip are at compatible versions.
### Example Dockerfile Addition
dockerfile
FROM prefecthq/prefect:2-latest
RUN pip install pandas
### Prefect Deployment YAML Example
Ensure your prefect.yaml
file correctly configures environment and dependencies:
yaml
deployments:
- name: repo-deploy
work_pool_name: my-docker-pool
cron: "0 0 * * *"
entrypoint: "main.py:main"
parameters: {}
tags: ["dev", "repo"]
build: false
job_variables:
env:
EXTRA_PIP_PACKAGES: "pandas"
### Sources
- Issue with Simultaneous Running Deployed Flows
- ScriptError when Dependencies Fail to Install
- GitHub Repository Integration with Prefect
By addressing these areas, you should be able to resolve the ModuleNotFoundError
and ensure your flow runs smoothly.Joshua Caskie
06/25/2024, 12:49 PMimage
parameter of flow.deploy()
with an image that has pandas installed? Or should I leave it blank and let Prefect build and name it?Marvin
06/25/2024, 12:49 PMpandas
or any other dependencies are available during the execution of your flow, you should specify the image
parameter in your flow.deploy()
method with a pre-built Docker image that contains these dependencies, such as pandas
.
### Option 1: Specifying a Custom Docker Image
You can create a Docker image that includes all necessary dependencies and specify it in the image
parameter. This ensures that all required libraries are present when the flow runs.
### Example
1. Create Dockerfile:
dockerfile
FROM prefecthq/prefect:2-latest
RUN pip install pandas
2. Build and Push Docker Image:
sh
docker build -t my-repo/my-image:my-tag .
docker push my-repo/my-image:my-tag
3. Deploy Flow Using Custom Image:
python
from prefect import flow
from prefect.deployments import Deployment
git_repo = GitRepository(
url="my/git/repo.git",
branch="develop",
credentials=GitLabCredentials.load("repo-prefect")
)
deployment = Deployment(
flow=flow.from_source(
source=git_repo,
entrypoint="main.py:main"
),
name="repo-deploy",
work_pool_name="my-docker-pool",
cron="0 0 * * *",
image="my-repo/my-image:my-tag",
tags=["dev", "repo"],
job_variables={"env": {"EXTRA_PIP_PACKAGES": "pandas"} },
build=False
)
deployment.deploy()
### Option 2: Allow Prefect to Build the Image
If you prefer to let Prefect handle the image building, ensure that a requirements.txt
file with pandas
listed is present in your repository, and Prefect will include it in the Docker build.
### Example
1. Add requirements.txt
to Your Repo:
txt
pandas
2. Deploy Flow Without Specifying Image:
python
from prefect import flow
from prefect.deployments import Deployment
git_repo = GitRepository(
url="my/git/repo.git",
branch="develop",
credentials=GitLabCredentials.load("repo-prefect")
)
deployment = Deployment(
flow=flow.from_source(
source=git_repo,
entrypoint="main.py:main"
),
name="repo-deploy",
work_pool_name="my-docker-pool",
cron="0 0 * * *",
tags=["dev", "repo"],
job_variables={"env": {"EXTRA_PIP_PACKAGES": "pandas"} },
build=True # Set to True to build image with dependencies
)
deployment.deploy()
### Conclusion
Specifying a custom Docker image ensures that your dependencies are reliably included. Otherwise, if you rely on Prefect’s automated build process, ensure your repository has the proper requirements.txt
.
### Sources
- Prefect Deployment Guide
By following these steps, you should resolve the ModuleNotFoundError
and ensure your flow runs with all required dependencies.Joshua Caskie
06/25/2024, 12:52 PMdevelop
. I have build=True
in the flow.from_source().deploy()
method call. What else might it be?Marvin
06/25/2024, 12:52 PMModuleNotFoundError
for pandas
, even when letting Prefect build the image. Here are a few additional steps and considerations to ensure the environment is correctly set up.
### Verify Docker Build Process
Ensure the Docker build process is properly incorporating your requirements.txt
.
1. Check Docker Build Logs: Verify that during the Docker build process, pandas
is being installed without errors. The logs should show something like:
Collecting pandas
Downloading pandas-1.3.3.tar.gz (4.7 MB)
2. Validate Docker Image: After Prefect builds the Docker image, verify the image has pandas
installed by running a container from the built image.
### Using Prefect's Custom Build Steps
Ensure you are following Prefect's recommended practices for custom build steps.
### Example Prefect YAML Configuration
Your prefect.yaml
should correctly specify the Docker build parameters. Here's an example:
yaml
name: repo-deploy
description: A deployment configuration for the repo flow.
work_pool:
name: my-docker-pool
schedule:
cron: "0 0 * * *"
tags:
- dev
- repo
storage:
- type: prefect_docker.deployments.steps.build_docker_image
requires: prefect-docker>=0.3.0
image_name: my-repo/my-image
tag: my-tag
dockerfile: auto
push: true
job:
env:
EXTRA_PIP_PACKAGES: "pandas"
### Explicitly Specify Dependencies
Add a custom_dockerfile
to ensure dependencies are explicitly included during the build process. This might help in certain edge cases where the automated process fails.
yaml
name: repo-deploy
description: A deployment configuration for the repo flow.
work_pool:
name: my-docker-pool
schedule:
cron: "0 0 * * *"
tags:
- dev
- repo
storage:
- type: prefect_docker.deployments.steps.build_docker_image
requires: prefect-docker>=0.3.0
image_name: my-repo/my-image
tag: my-tag
dockerfile: ./Dockerfile
push: true
job:
env:
EXTRA_PIP_PACKAGES: "pandas"
.build:
steps:
- prefect_docker.deployments.steps.build_docker_image:
image_name: my-repo/my-image
tag: my-tag
dockerfile: "./Dockerfile"
push: true
### Example Dockerfile
Ensure your Dockerfile
is correctly set up in the repository (if not using the auto build):
dockerfile
FROM prefecthq/prefect:2-latest
COPY requirements.txt .
RUN pip install -r requirements.txt
### Conclusion
- Verify Docker Build Logs: Ensure pandas
is installed without errors.
- Inspect Built Image: Validate that the built Docker image contains pandas
.
- Customize Docker Build Steps: Use explicit build steps and configurations in prefect.yaml
.
By ensuring these steps, you should resolve dependency issues and ensure pandas
is included in your Prefect flow execution environment. If problems persist, please share any additional error logs or details for more precise assistance.