# ML Pipeline Development Guideline

This document describes the development guideline to contribute to ML pipeline project. Please check the [main page](https://github.com/kubeflow/pipelines/blob/master/README.md) for instruction on how to deploy a ML pipeline system.

## ML pipeline deployment

The Pipeline system is included in kubeflow. See [Getting Started Guide](https://www.kubeflow.org/docs/started/getting-started/) for how to deploy with Kubeflow.

## Build Image

### GKE
To be able to use GKE, the Docker images need to be uploaded to a public Docker repository, such as [GCR](https://cloud.google.com/container-registry/)

To build the API server image and upload it to GCR:
```bash
# Run in the repository root directory
$ docker build -t gcr.io/<your-gcp-project>/api-server:latest -f backend/Dockerfile .
# Push to GCR
$ gcloud auth configure-docker
$ docker push gcr.io/<your-gcp-project>/api-server:latest
```

To build the scheduled workflow controller image and upload it to GCR:
```bash
# Run in the repository root directory
$ docker build -t gcr.io/<your-gcp-project>/scheduledworkflow:latest -f backend/Dockerfile.scheduledworkflow .
# Push to GCR
$ gcloud auth configure-docker
$ docker push gcr.io/<your-gcp-project>/scheduledworkflow:latest
```

To build the viewer CRD controller image and upload it to GCR:
```bash
# Run in the repository root directory
$ docker build -t gcr.io/<your-gcp-project>/viewer-crd-controller:latest -f backend/Dockerfile.viewercontroller .
# Push to GCR
$ gcloud auth configure-docker
$ docker push gcr.io/<your-gcp-project>/viewer-crd-controller:latest
```

To build the persistence agent image and upload it to GCR:
```bash
# Run in the repository root directory
$ docker build -t gcr.io/<your-gcp-project>/persistenceagent:latest -f backend/Dockerfile.persistenceagent .
# Push to GCR
$ gcloud auth configure-docker
$ docker push gcr.io/<your-gcp-project>/persistenceagent:latest
```

To build the frontend image and upload it to GCR:
```bash
# Run in the repository root directory
$ docker build -t gcr.io/<your-gcp-project>/frontend:latest -f frontend/Dockerfile .
# Push to GCR
$ gcloud auth configure-docker
$ docker push gcr.io/<your-gcp-project>/frontend:latest
```

### Minikube
Minikube can pick your local Docker image so you don't need to upload to remote repository.

For example, to build API server image
```bash
$ docker build -t ml-pipeline-api-server -f backend/Dockerfile .
```

## Python based visualizations

Python based visualizations are a new method to visualize results within the
Kubeflow Pipelines UI. For more information about Python based visualizations
please visit the [documentation page](https://www.kubeflow.org/docs/pipelines/sdk/python-based-visualizations).
To create predefine visualizations please check the [developer guide](https://github.com/kubeflow/pipelines/blob/master/backend/src/apiserver/visualization/developer_guide.md). 

## Unit test

### API server
Run unit test for the API server
```bash
cd backend/src/ && go test ./...
```
### Frontend
TODO: add instruction

### DSL
```bash
pip install ./dsl/ --upgrade && python ./dsl/tests/main.py
pip install ./dsl-compiler/ --upgrade && python ./dsl-compiler/tests/main.py
```

## Integration test & E2E test

Check [this](https://github.com/kubeflow/pipelines/blob/master/test/README.md) page for more details.

## Troubleshooting

**Q: How to access to the database directly?**

You can inspect mysql database directly by running:
```bash
kubectl run -it --rm --image=gcr.io/ml-pipeline/mysql:5.6 --restart=Never mysql-client -- mysql -h mysql
mysql> use mlpipeline;
mysql> select * from jobs;
```

**Q: How to inspect object store directly?**

Minio provides its own UI to inspect the object store directly:
```bash
kubectl port-forward -n ${NAMESPACE} $(kubectl get pods -l app=minio -o jsonpath='{.items[0].metadata.name}' -n ${NAMESPACE}) 9000:9000
Access Key:minio
Secret Key:minio123
```

**Q: I see an error of exceeding Github rate limit when deploying the system. What can I do?**

See [Ksonnet troubleshooting page](https://github.com/ksonnet/ksonnet/blob/master/docs/troubleshooting.md#github-rate-limiting-errors)

**Q: How do I check my API server log?**

API server logs are located at /tmp directory of the pod. To SSH into the pod, run:
```bash
kubectl exec -it -n ${NAMESPACE} $(kubectl get pods -l app=ml-pipeline -o jsonpath='{.items[0].metadata.name}' -n ${NAMESPACE}) -- /bin/sh
```
or
```bash
kubectl logs -n ${NAMESPACE} $(kubectl get pods -l app=ml-pipeline -o jsonpath='{.items[0].metadata.name}' -n ${NAMESPACE})
```

**Q: How to check my cluster status if I am using Minikube?**

Minikube provides dashboard for deployment
```bash
minikube dashboard
```
