[MKP/doc] Update doc for changes of service account credential. (#2309)

* Update README for MKP development. Remove managed SQL part and update verison tag.

* Update guide for MKP deployment.

* Small fix.

* fix one missing thing

manifests/gcp_marketplace/README.md

@@ -115,12 +115,6 @@ Creat the namespace
 kubectl create namespace $NAMESPACE
 ```
 
-Download token for your service account which you want to use for calling GCP APIs from the pipelines.
-```shell
-gcloud iam service-accounts keys create application_default_credentials.json --iam-account [your-service-account]
-export SERVICE_ACCOUNT_TOKEN="$(cat application_default_credentials.json | base64 -w 0)"
-```
-
 Follow the [instruction](https://github.com/GoogleCloudPlatform/marketplace-k8s-app-tools/blob/master/docs/tool-prerequisites.md#tool-prerequisites) and install mpdev
 TODO: The official mpdev won't work because it doesn't have permission to deploy CRD. The latest unofficial build will have right permission. Remove following instruction when change is in prod.
 ```
@@ -134,15 +128,10 @@ export MARKETPLACE_TOOLS_IMAGE=gcr.io/cloud-marketplace-staging/marketplace-k8s-
 Run the install script
 
 ```shell
-mpdev scripts/install  --deployer=gcr.io/ml-pipeline/google/pipelines/deployer:0.2   --parameters='{"name": "'$APP_INSTANCE_NAME'", "namespace": "'$NAMESPACE'", "serviceAccountCredential": "'$SERVICE_ACCOUNT_TOKEN'"}'
+mpdev scripts/install  --deployer=gcr.io/ml-pipeline/google/pipelines/deployer:0.1   --parameters='{"name": "'$APP_INSTANCE_NAME'", "namespace": "'$NAMESPACE'"}'
 
 ```
 
-Or if using CloudSQL and GCS,
-```
-mpdev scripts/install  --deployer=gcr.io/ml-pipeline/google/pipelines/deployer:0.2   --parameters='{"name": "'$APP_INSTANCE_NAME'", "namespace": "'$NAMESPACE'", "serviceAccountCredential": "'$SERVICE_ACCOUNT_TOKEN'", "managedstorage.enabled": true, "managedstorage.cloudsqlInstanceConnectionName": "[your-name]", "managedstorage.dbPassword": "[your-pwd]"}'
-```
-
 Watch the deployment come up with
 
 ```shell

manifests/gcp_marketplace/guide.md

@@ -17,26 +17,43 @@ Specify a [Kubenetes namespace](https://kubernetes.io/docs/concepts/overview/wor
 ## App instance name
 Specify an app instance name to help you identify this instance.
 
+## Deploy
+Click `Deploy` to start deploying Kubeflow Pipelines into the cluster you specified.
+Deployment might take few minutes, so please be patient. After deployment is complete, go to the [Pipelines Console](http://pantheon.corp.google.com/ai-platform/pipelines) to access the Kubeflow Pipelines instance.
+
 ## GCP Service Account credentials
-This deployment requires a [GCP service account](https://cloud.google.com/iam/docs/service-accounts) to use for authentication when calling other GCP services. This includes Cloud Storage and Cloud SQL if you are using managed storage, as well as other services your pipeline might need, for example Dataflow. Specify the base64-encoded credentials for the service account you want to use.
+After deployment, you can grant KFP proper permission by specifying its service account and binding
+proper role to it.
 
-You can get these credentials by running the following command in a terminal window. This command will create a new key under the service account. Please note that a single service account can only have 10 keys. 
+Usually a functional KFP pipeline requires a [GCP service account](https://cloud.google.com/iam/docs/service-accounts) to use for 
+authentication when calling other GCP services. This includes Cloud Storage as well as other services your pipeline might need, 
+for example Dataflow, Dataproc. Specify the base64-encoded credentials for the service account you want to use.
 
+This can be done through command line using `kubectl`.
 ```
-$ gcloud iam service-accounts keys create application_default_credentials.json --iam-account [your-service-account] && cat application_default_credentials.json | base64
+export CLUSTER=<cluster-where-kfp-was-installed>
+export ZONE=<zone-where-kfp-was-installed>
+# Configure kubectl to connect with the cluster
+gcloud container clusters get-credentials "$CLUSTER" --zone "$ZONE"
 ```
-
-Existing key also can be used.
-
+Then you can create and inject service account credential.
 ```
-cat existing_credentials.json | base64
+export PROJECT=<my-project>
+export SA_NAME=<my-account>
+# Create service account
+gcloud iam service-accounts create $SA_NAME --display-name $SA_NAME
+gcloud projects add-iam-policy-binding $PROJECT --member=serviceAccount:my-account@$PROJECT.iam.gserviceaccount.com --role=roles/storage.admin
+# Also do this binding for other roles you need. For example, dataproc.admin and dataflow.admin
+gcloud iam service-accounts keys create application_default_credentials.json --iam-account $SA_NAME@$PROJECT.iam.gserviceaccount.com
+export SERVICE_ACCOUNT_TOKEN="$(cat application_default_credentials.json | base64 -w 0)"
+echo -e "apiVersion: v1\nkind: Secret\nmetadata:\n  name: \"user-gcp-sa\"\n  namespace: \"${NAMESPACE}\"\n  labels:\n    app: gcp-sa\n    app.kubernetes.io/name: \"${APP_INSTANCE_NAME}\"\ntype: Opaque\ndata:\n  application_default_credentials.json: ${SERVICE_ACCOUNT_TOKEN}\n  user-gcp-sa.json: $SERVICE_ACCOUNT_TOKEN" > secret.yaml
+kubectl apply -f secret.yaml
+# Remove secret files
+rm application_default_credentials.json test.yaml
 ```
 
-If you are running this command on Linux, please use `base64 -w 0` to disable line wrapping.
-
-## Deploy
-Click `Deploy` to start deploying Kubeflow Pipelines into the cluster you specified.
-Deployment might take few minutes, so please be patient. After deployment is complete, go to the [Pipelines Console](http://pantheon.corp.google.com/ai-platform/pipelines) to access the Kubeflow Pipelines instance.
+Note that the above commands use `base64 -w 0` to disable line wrapping, this could be slightly different
+across platforms.
 
 ## Tips