## io.Storage


Options for the object store tables live in (credentials, region,


Usage

``` python
io.Storage(options=None)
```


endpoint), given once and passed to every source and sink that needs them: `DeltaSource(uri, storage_options=s3)`.

[options](io.Storage.md#sverify.io.Storage.options) is either a fixed mapping or a function returning a fresh one, called every time a table is opened, so a long-running job can renew an expiring token. sverify keeps no result of that function, and `repr` shows option names, never values. Prefer what the store's default chain finds (environment variables, `~/.aws` profiles, instance or pod roles) or a function that fetches short-lived credentials over literal keys, which travel with any object holding them.

The options are delta-rs's (`deltalake`'s `storage_options`), such as `AWS_REGION`, `AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`, `AWS_SESSION_TOKEN`, `GOOGLE_SERVICE_ACCOUNT` or `AZURE_STORAGE_ACCOUNT_NAME`. A source or sink of your own can take a [Storage](io.Storage.md#sverify.io.Storage) too and call [options()](io.Storage.md#sverify.io.Storage.options).


## Parameters


`options: Mapping[str, str] | Callable[[], Mapping[str, str]] | None = None`  
The options, or a function returning them. Default: none, the store's default chain.


## Examples

``` python
import boto3
from sverify.io import DeltaSink, DeltaSource, Storage


def credentials():
    c = boto3.Session().get_credentials().get_frozen_credentials()
    return {
        "AWS_REGION": "eu-central-1",
        "AWS_ACCESS_KEY_ID": c.access_key,
        "AWS_SECRET_ACCESS_KEY": c.secret_key,
        "AWS_SESSION_TOKEN": c.token or "",
    }


s3 = Storage(credentials)
orders = DeltaSource("s3://lake/orders", storage_options=s3)
sink = DeltaSink("s3://lake/paid", storage_options=s3)
```


## Methods

| Name | Description |
|----|----|
| [options()](#options) | The options now: the mapping, or what the function returns. |

------------------------------------------------------------------------


#### options()


The options now: the mapping, or what the function returns.


Usage

``` python
options()
```


##### Returns


`dict[str, str]`  
A new dict of options.