Configuration

Overview

This section explains how to completely configure a WorkflowGen database container. Everything is configurable via an environment variable.

Notes

Environment variables

Variables specific to the base images

Some variables are available in the base images that provide functionalities related to SQL Server. For the Linux version, see the mcr.microsoft.com/mssql/server Docker Hub page and the Configure SQL Server container images on Docker Microsoft article. For the Windows version, see the microsoft/mssql-server-windows-express Docker Hub page.

Some environment variables in the base images are required. For example, you have to provide a value for the SA_PASSWORD environment variable.

Variables specific to WorkflowGen

The WorkflowGen database container adds special environment variables to enable additional features related to WorkflowGen. The following table provides descriptions for each of them:

Variable

Description & values

WFGEN_DATABASE_NAME

The name of the WorkflowGen database

Default value: WFGEN

WFGEN_DATABASE_CONTAINMENT

Sets the WorkflowGen database to contain database users for more portability (see contained database authentication Server Configuration Option for more information)

Possible values: Y (default), N

WFGEN_DATABASE_USER_USERNAME

The username of the database user that has access to the WorkflowGen database

Default value: WFGEN_USER

WFGEN_DATABASE_USER_PASSWORD

Required variable

The password of the database user that has access to the WorkflowGen database

WFGEN_DATABASE_FILE_PATH

Do not modify for Linux version

Internal path to the .mdf and .ldf database files inside the container

Default value:

  • Windows: C:\wfgen\sql

  • Linux: /var/opt/mssql/data

WFGEN_ADMIN_USERNAME

The username of the WorkflowGen administrative user

Default value: wfgen_admin

WFGEN_ADMIN_PASSWORD

Required variable

The password of the WorkflowGen administrative user

WFGEN_AUTH_APPLICATION

Indicates if the authentication method of WorkflowGen is applicative or not

Possible values: Y (default), N

Format-based environment variables

Secrets

When using an orchestrator such as Kubernetes, you'll probably want to secure secrets using their built-in secret management tools. Follow the specific guide for your orchestrator to know how to create a secret.

For Kubernetes, see https://kubernetes.io/docs/concepts/configuration/secret/.

It's recommended to inject secrets into WorkflowGen containers as files because they won't be exposed as environment variables and they'll be removed from the container when it's stopped or removed.

Secrets management is only possible using an orchestrator.

In order to get the secret value in the file, you need to suffix any environment variable you want to get the value of in this way with _FILE and set its value to the path of the file containing the secret. The container will then get the value in the file at the specified path and set the environment variable without the suffix with that value.

For example, let's say you want to set sa account password in SQL Server to strong(!)Pass using the environment variable SA_PASSWORD, but you want to use a secret for the value. All you have to do is suffix the environment variable name with _FILEso that it becomes SA_PASSWORD_FILE. Then, set the value of this variable to the path of the file containing the password.

Here's an example with the Docker Swarm orchestrator:

PowerShell
Bash
PowerShell
# Create the secret for the license serial number
'strong(!)Pass' | docker secret create SA_PASSWORD -
# Create the container service in Docker Swarm
docker service create `
# ...
--env WFGEN_APP_SETTING_ApplicationSerialNumber_FILE=/run/secrets/SA_PASSWORD `
--secret SA_PASSWORD `
# ...
advantys/workflowgen-sql:7.18.3-ubuntu-18.04
Bash
# Create the secret for the license serial number
echo 'strong(!)Pass' | docker secret create SA_PASSWORD -
# Create the container service in Docker Swarm
docker service create \
# ...
--env WFGEN_APP_SETTING_ApplicationSerialNumber_FILE=/run/secrets/SA_PASSWORD \
--secret SA_PASSWORD \
# ...
advantys/workflowgen-sql:7.18.3-ubuntu-18.04

For Kubernetes, you would create a ConfigMap that complements your secret like this:

apiVersion: v1
kind: ConfigMap
metadata:
name: database-config
data:
SA_PASSWORD_FILE: /mnt/secrets/SA_PASSWORD
---
apiVersion: v1
kind: Secret
type: Opaque
metadata:
name: database-secret
data:
# "c3Ryb25nKCEpUGFzcwo=" is the base64-encoded value of "strong(!)Pass"
SA_PASSWORD: 'c3Ryb25nKCEpUGFzcwo='

Then, you would map the ConfigMap as environment variables and mount the secret as a volume like this:

apiVersion: apps/v1
kind: StatefulSet
metadata:
name: wfgen-database
spec:
selector:
matchLabels:
# ...
template:
metadata:
labels:
# ...
spec:
containers:
- name: database
image: advantys/workflowgen-sql:7.18.3-ubuntu-18.04
# ...
envFrom: # ConfigMap as environment variables
- configMapRef:
name: database-config
# ...
volumeMounts:
# ...
- mountPath: /mnt/secrets # Mount Secret as a volume
readOnly: true
name: secrets
volumes:
# ...
- name: secrets # Mount Secret as a volume
secret:
secretName: database-secret

Using an orchestrator

Kubernetes

Kubernetes also has a built-in object called ConfigMap to manage pod configuration. See the Configure a Pod to Use a ConfigMap Kubernetes article for more information and how to use it. You should use this object to configure environment variables for WorkflowGen.

You can also manage sensitive information by protecting it further in the orchestrator in a secure area. See the Secrets Kubernetes article for more information and instructions on how to use it. You should use this object to protect sensitive information such as the WorkflowGen license key, usernames, passwords, cryptographic keys, API keys, etc.

Using an external configuration manager

Some popular configuration managers support Docker containers out-of-the-box. Here are a few links to their specific documentation to get you started:

Chef

Ansible

Puppet

About security features

The Linux version of the database has some security features that can be used to improve the overall security of the database. For more information on security features in SQL Server for Linux, see Configure SQL Server container images on Docker in the Microsoft SQL Server documentation.

The Windows version of the container doesn't have the security features of the Linux version. It's advised to use the Windows version only for development and testing purposes.

Performance & high availability

You can configure replication with this container, but you'll have to make a custom image. For more information about making a custom image, see the Custom Image page of this section. For more information about configuring replication in SQL Server, see Configure a SQL Server Availability Group for read-scale on Linux in the Microsoft documentation.

Use with Kubernetes

You should always deploy the database container within a StatefulSet so that each container has its own separated storage. It also ensures that each container has a unique DNS name inside the cluster so that it can be found easily by other containers. You can also configure each of the instances based on an incremental identifier so that you can set a read/write instance and several read-only instances. Here's an example of a simple StatefulSet deployment with the WorkflowGen database container:

apiVersion: v1
kind: Service
metadata:
name: database
spec:
type: ClusterIP
clusterIP: None
ports:
- port: 1433
targetPort: mssql
protocol: TCP
name: mssql
selector:
app.kubernetes.io/name: workflowgen
app.kubernetes.io/component: database
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: database
spec:
replicas: 1
serviceName: database
selector:
matchLabels:
app.kubernetes.io/name: workflowgen
app.kubernetes.io/component: database
template:
metadata:
labels:
app.kubernetes.io/name: workflowgen
app.kubernetes.io/component: database
spec:
terminationGracePeriodSeconds: 10
nodeSelector:
kubernetes.io/os: linux
containers:
- name: database
image: advantys/workflowgen-sql:7.18.3-ubuntu-18.04
imagePullPolicy: Always
securityContext:
runAsUser: 0
runAsGroup: 0
resources:
requests:
memory: "1Gi"
cpu: "500m"
limits:
memory: "2Gi"
cpu: "1"
envFrom:
- configMapRef:
name: database-config
ports:
- name: mssql
containerPort: 1433
livenessProbe:
initialDelaySeconds: 30
timeoutSeconds: 5
exec:
command:
- pwsh
- -NoLogo
- -NoProfiles
- /usr/local/bin/healthcheck.ps1
readinessProbe:
initialDelaySeconds: 20
timeoutSeconds: 5
exec:
command:
- pwsh
- -NoLogo
- -NoProfiles
- /usr/local/bin/healthcheck.ps1
volumeMounts:
- mountPath: /var/opt/mssql
name: sqldata
- mountPath: /mnt/secrets
readOnly: true
name: secrets
volumes:
- name: secrets
secret:
secretName: database-sec
volumeClaimTemplates:
- metadata:
name: sqldata
spec:
accessModes:
- ReadWriteOnce
storageClassName: default
resources:
requests:
storage: 100Gi

You can use this example as a starting point to configure multiple database containers. For more information about StatefulSets, see StatefulSets in the Kubernetes documentation. You might need custom code to be able to configure multiple instances properly. See the Custom Image page of this section for more information about how you can add custom code to the container.