Book Image

Microsoft Azure Development Cookbook Second Edition

Book Image

Microsoft Azure Development Cookbook Second Edition

Overview of this book

Table of Contents (15 chapters)
Microsoft Azure Development Cookbook Second Edition
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Setting properties and metadata for a blob


The Azure Blob service allows metadata and properties to be associated with a blob. The metadata comprises a sequence of developer-defined, name-value pairs. The properties comprise HTTP request headers, which include Cache-Control, Content-Encoding, Content-MD5, and Content-Type. The Blob service also supports metadata and properties for blob containers. Requesting a download of the blob attributes, its metadata, and properties is an efficient way of checking blob existence, as only a small amount of data is downloaded.

The Blob service uses the Content-MD5 property to validate blob upload. When specified, the Content-MD5 property must be set to the base64-encoded value of the MD5 hash's blob data. The Blob service returns an error if this value does not match the value it calculates from the uploaded blob content.

In this recipe, we'll learn how to set and get blob properties and metadata. We will also learn how to calculate the Content-MD5 property...