Local Storage Agent - C Sharp

Read and write value in local storage.

Logic Type	Available
Generic logic	✅
Aggregator logic	❌

Local Storage

Unlike a task's session storage, the local storage is implemented in Kubernetes' etcd database and can be accessed by different tasks. Data can stay persistent after executions for a limit amount of time.

The local storage is not meant as the primary way to exchange data across tasks, more like a debugging or testing tool.

Import and Usage

The agent can be used without using additional namespaces:

public static class Logic
{

    public static async Task Run(Context ctx)
    {
        var data = (await LocalStorageAgent.Get("data"))?.JsonValue;
    }

    public static async Task HandleError(Context ctx, Exception error)
    {
        // ... same
    }
}

Class Reference

Type

• Public static class LocalStorageAgent

Method: Get Local Value

public async static Task<StorageValue?> Get(string key) {}

Parameter	Description
key	Key of local data

Returns a StorageValue value from local storage (null if not exist).

Method: Write Local Value

public async static Task Put(string key, StorageValue value, ulong? timeoutSeconds = null) {}

Parameter	Description
key	Key of local data
value	StorageValue data
timeout	(Optional) data persistent time (seconds; default 300, maximum 86400 = 1 day)

Write a StorageValue value into local storage. Overwrite if already exists.

Method: Delete Local Value

public async static Task Delete(string key) {}

Parameter	Description
key	Key of local data

Delete a value in local storage. Do nothing if not exist.

Sub Class Reference

StorageValue

Refer to: StorageValue

Examples

See the example of session storage agent for more detailed examples (replace LocalStorageAgent to SessionStorageAgent and without the timeout parameter).

Write String Data Into Local Storage

await LocalStorageAgent.Put(
    "data",
    StorageValue.FromString("so long, and thanks for all the fish"),
    86400  // persistent for 1 day
);

Write JSON Data Into Local Storage

await LocalStorageAgent.Put(
    "data",
    StorageValue.FromJson(
        new Dictionary<string, object?>()
        {
            // ...
        }
    ),
    86400  // persistent for 1 day
);

// or

/*
- import the following namespace:

using System.Text.Json.Nodes;
*/
await LocalStorageAgent.Put(
    "data",
    StorageValue.FromJson(
        new JsonObject
        {
            // ...
        }
    ),
    86400  // persistent for 1 day
);

Read String Data from Local Storage

string? data = (await LocalStorageAgent.Get("data"))?.StringValue;

Set a default value if the local data does not exist (returns null):

string data = (await LocalStorageAgent.Get("data"))?.StringValue ?? "default value";

Read Json Data from Local Storage

Import namespace(s)

using System.Text.Json.Nodes;

JsonNode? data = (await LocalStorageAgent.Get("data"))?.JsonValue;

// get values (null if not found)
string? name = data?["name"]?.GetValue<string>();
int? age = data?["age"]?.GetValue<int>();