State store configuration

In this section, you will learn how to set up state stores in Taskurai.

State stores are defined in the Taskurai configuration (YAML) and are deployed and managed using the Taskurai CLI.

State store deployment configuration

A state store is deployed using a configuration section in the solution yaml.

Reference state store configuration

This is a reference state store configuration sample:

• Internal state stores:
  • DefaultStateStore: stored in the default container and database.
  • ShoppingCartStore: stored in the cart container and database, scoped to the ShoppingCartWorker.
• Dedicated state stores:
  • VideoState: Uses the custom database and standard storage account, stored in the videostate container and database, scoped to the TranscriptionWorker and VideoEncodeWorker.
  • AudioState: Uses the custom database and standard storage account, stored in the audiostate container and database.
  • PremiumVideoState: Uses the premium database and premium storage account, stored in the premiumvideo container and database, scoped to the TranscriptionWorker and VideoEncodeWorker.

stateStores:
  DefaultStateStore:
    type: DefaultStateStore
    kind: Dedicated
    hub: DefaultHub
    environment:
    - name: containerName
      value: default
  ShoppingCartStore:
    type: DefaultStateStore
    kind: Dedicated
    hub: DefaultHub
    environment:
    - name: containerName
      value: cart
    scopes:
      - ShoppingCartWorker
  VideoState:
    type: DefaultStateStore
    kind: Dedicated
    hub: DefaultHub
    environment:
    - name: accountName
      value: custom
    - name: storageTier
      value: Standard_LRS
    - name: containerName
      value: videostate
    scopes: 
      - TranscriptionWorker
      - VideoEncodeWorker
  AudioState:
    type: DefaultStateStore
    kind: Dedicated
    hub: DefaultHub
    environment:
    - name: accountName
      value: custom
    - name: storageTier
      value: Standard_LRS
    - name: containerName
      value: audiostate
  PremiumVideoState:
    type: DefaultStateStore
    kind: Dedicated
    hub: DefaultHub
    environment:
    - name: accountName
      value: premium
    - name: storageTier
      value: Premium_ZRS
    - name: containerName
      value: premiumvideo
    scopes: 
      - TranscriptionWorker
      - VideoEncodeWorker

State store configuration

Property	Type	Required	Additional requirements	Description
name	string	No	1-20 alphanumeric characters and hyphens	Override state store name (default: state store key)
type	State store type	Yes		State store type
kind	State store kind	Yes		State store kind
hub	string	Yes		State store hub
secrets	List of secrets	No		List of secrets
environment	List of environment variables	Yes		List of state store configuration
scopes	List of workers names (string)	No		Limit access of state stores to a list of workers

State store type

State store kind	Description
DefaultStateStore	State store with database and storage container

State store kind

State store type	Description
Dedicated	A Dedicated state store can be configured to either share or have dedicated database and storage accounts, providing more throughput and avoiding noisy neighbor issues. You can choose between a standard or premium storage account, depending on your needs, such as storing large files with optimal performance and low latency.

Secret configuration

Each state store can contain secrets to be used in environment variables.

Secret properties:

Property	Type	Required	Description
name	string	Yes	Secret name
secretReference	string	No	Global secret reference (recommended)
value	string	No	Secret value (not recommended)

While it is technically possible to define a secret value directly in the state store configuration, it is highly recommended to use globally defined secrets in Taskurai and reference them in the state store.

options:
  ...
secrets:
  - myglobalcontainerregistrypassword
  - myglobalsecret
workers:
  TestWorker:
    container:
      ...
      passwordSecretReference: containerregistrypassword
      ...
    secrets: 
      - name: containerregistrypassword
        secretReference: myglobalcontainerregistrypassword
      - name: mycontainersecret
        secretReference: myglobalsecret
    environment:
      - name: ENV_WITH_SECRET
        secretReference: mycontainersecret
      - name: ENV_WITH_VALUE
        value: myvalue
      ...

Notice that the global Taskurai secret can only be referenced in the state store secret configuration. To use secrets within the state store itself, the local secrets defined in the state store should be used.

Environment configuration

Environment variables can be set to be used in containers.

Environment variable properties:

Property	Type	Required	Description
name	string	Yes	Variable name
secretReference	string	No	Reference to a state store secret
value	string	No	Variable value

An environment variable can either be a plain text value or can reference a state store secret.

options:
  ...
secrets:
  - myglobalcontainerregistrypassword
  - myglobalsecret
stateStores:
  ShoppingCartStore:
    ...
    secrets: 
      ...
      - name: mycontainersecret
        secretReference: myglobalsecret
    environment:
      - name: ENV_WITH_SECRET
        secretReference: mycontainersecret
      - name: ENV_WITH_VALUE
        value: myvalue
      ...

Dedicated state stores

Dedicated state stores can be configured to either share or have dedicated database and storage accounts, providing more throughput and avoiding noisy neighbor issues.

You can choose between a standard or premium storage account, depending on your needs, such as storing large files with optimal performance and lower latency.

Depending on the Taskurai Plan, it is possible to define multiple Dedicated state stores, either sharing the same resources or being set up with dedicated resources.

Dedicated state store configuration

State stores are configured using the following environment variables:

Property	Type	Required	Default	Additional requirements	Description
accountName	string	Yes		1-9 lowercase alphanumeric characters and hyphens	State database and storage account name
storageTier	Storage tier	Yes			State database and storage container name
containerName	string	Yes		1-20 lowercase alphanumeric characters and hyphens	State database and storage container name
consistencyLevel	Consistency level	No	Session		Default state store consistency level

Storage tier

Storage tier	Description
Standard_LRS	Standard Storage Account, Locally-redundant storage
Standard_GRS	Standard Storage Account, Geo-redundant storage
Standard_ZRS	Standard Storage Account, Zone-redundant storage
Standard_GZRS	Standard Storage Account, Geo-Zone-redundant storage
Premium_LRS	Premium Storage Account, Locally-redundant storage
Premium_ZRS	Premium Storage Account, Zone-redundant storage

Consistency level

Reflects the Cosmos DB consistency levels:

Consistency level	Description
Strong	Strong Consistency guarantees that read operations always return the value that was last written.
BoundedStaleness	Bounded Staleness guarantees that reads are not too out-of-date.
Session	Session Consistency guarantees monotonic reads (you never read old data, then new, then old again), monotonic writes (writes are ordered) and read your writes (your writes are immediately visible to your reads) within any single session.
ConsistentPrefix	ConsistentPrefix Consistency guarantees that reads will return some prefix of all writes with no gaps. All writes will be eventually be available for reads.
Eventual	Eventual Consistency guarantees that reads will return a subset of writes. All writes will be eventually be available for reads.

Pricing

info

Taskurai deploys database and storage resources in a Taskurai Hub, installed in your Azure subscription, to implement states stores. RU-based billing and additional Azure resource costs apply.

For more information:

Pricing information of Azure Cosmos DB

Pricing information of Azure Storage