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Tutorial: Set up a vcpkg asset cache

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All asset caches are configured through the X_VCPKG_ASSET_SOURCES environment variable. The value of X_VCPKG_ASSET_SOURCES follows a specific configuration syntax.

In this tutorial you'll learn how to:

Prerequisites

  • A terminal
  • vcpkg

1 - Create an asset cache directory

You can use the Azure Blob Storage backend "x-azurl", to store assets. Alternatively, you can use a filesystem directories to store your download assets, including network locations. To do so, you need to use the file:// protocol in your asset cache URL.

In this tutorial, you'll create a local asset cache location to store downloaded artifacts. If you have an Azure DevOps Blob Storage you want to use instead, replace the URL and provide a SAS token as the second parameter in the configuration string.

  1. Create a directory to serve as an asset cache location (substitute with any locations of your choosing):
mkdir D:\vcpkg\asset-cache

mkdir /home/vcpkg/asset-cache

2 - Configure X_VCPKG_ASSET_SOURCES

Next set the value of X_VCPKG_ASSET_SOURCES as follows:

$env:X_VCPKG_ASSET_SOURCES="clear;x-azurl,file://D:/vcpkg/asset-cache,,readwrite"

set X_VCPKG_ASSET_SOURCES="clear;x-azurl,file://D:/vcpkg/asset-cache,,readwrite"

This X_VCPKG_ASSET_SOURCES configuration adds the following source strings:

  • clear, disables any previously configured asset cache
  • x-azurl,file://C:/vcpkg/asset-cache,,readwrite, sets a filesystem asset cache, located in D:\vcpkg\asset-cache, with read-write permissions.
export X_VCPKG_ASSET_SOURCES="clear;x-azurl,file:///home/vcpkg/asset-cache,,readwrite"

This X_VCPKG_ASSET_SOURCES configuration adds the following source strings:

  • clear, disables any previously configured asset cache
  • x-azurl,file:///home/vcpkg/asset-cache,,readwrite, sets a filesystem asset cache, located in home/vcpkg/asset-cache, with read-write permissions.

Next steps

Here are other tasks to try next: