storr_external

storr for fetching external resources. This driver is used where
will try to fetch from an external data source if a resource can
not be found locally. This works by checking to see if a key is
present in the storr (and if so returning it). If it is not
found, then the function <code>fetch_hook</code> is run to fetch it.

Creates and manages simple key-value stores.  These can
use a variety of approaches for storing the data.  This package
implements the base methods and support for file system, in-memory
and DBI-based database stores.

Rich FitzJohn

storr

Simple Key Value Stores

storr_external function

<dl><dt>storage_driver</dt>
<dd>Another <code>storr</code> driver to handle the
actual storage.</dd>
<dt>fetch_hook</dt>
<dd>A function to run to fetch data when a key is
not found in the store. This function must take arguments
<code>key</code> and <code>namespace</code> and return an R object. It must
throw an error if the external resource cannot be resolved.</dd>
<dt>default_namespace</dt>
<dd>Default namespace (see
storr)</dd></dl>

Arguments

Storr that looks for external resources — storr_external

<dl>

<dt>storage_driver</dt>
<dd>Another <code>storr</code> driver to handle the
actual storage.</dd>


<dt>fetch_hook</dt>
<dd>A function to run to fetch data when a key is
not found in the store. This function must take arguments
<code>key</code> and <code>namespace</code> and return an R object. It must
throw an error if the external resource cannot be resolved.</dd>


<dt>default_namespace</dt>
<dd>Default namespace (see
storr)</dd>

</dl>

storr_external: Storr that looks for external resources

Description

Usage

Arguments

Details