regex - 用于用户输入验证的 Azure Blob 存储正则表达式模式

Question

我在 PowerShell (.NET Framework) 中开发了一个函数，用于从任何给定的 Azure Blob 存储中检索数据:到目前为止，一切顺利。

不幸的是，当涉及到验证用户的输入时，我不能依赖外部模块或库，例如 NameValidator Class适用于 .NET 的 Azure SDK。

尽管如此，文章Naming and Referencing Containers, Blobs, and Metadata详细介绍了命名规则，因此正则表达式模式可能会派上用场。

对于容器名称，我想出了这个，它似乎很合适:

(?=^.{3,63}$)(?!.*--)[^-][a-z0-9-]*[^-]

容器名称

A container name must be a valid DNS name, conforming to the following naming rules:

• Container names must start or end with a letter or number, and can contain only letters, numbers, and the dash (-) character.
• Every dash (-) character must be immediately preceded and followed by a letter or number; consecutive dashes are not permitted in container names.
• All letters in a container name must be lowercase.
• Container names must be from 3 through 63 characters long.

对于Blob名称，但是我无法绕过路径段的计数:

(?=^.{1,1024}$)(?<=^|\/)(\S*?)[^\.] (?=\/|$)

注意:Azure 存储模拟器已被弃用，因此超出了范围。

Blob 名称

A blob name must conforming to the following naming rules:

• A blob name can contain any combination of characters.
• A blob name must be at least one character long and cannot be more than 1,024 characters long, for blobs in Azure Storage.
• The Azure Storage emulator supports blob names up to 256 characters long. For more information, see Use the Azure storage emulator for development and testing.
• Blob names are case-sensitive.
• Reserved URL characters must be properly escaped.
• The number of path segments comprising the blob name cannot exceed 254. A path segment is the string between consecutive delimiter characters (e.g., the forward slash '/') that corresponds to the name of a virtual directory.
• Note Avoid blob names that end with a dot (.), a forward slash (/), or a sequence or combination of the two. No path segments should end with a dot (.).

The Blob service is based on a flat storage scheme, not a hierarchical scheme. However, you may specify a character or string delimiter within a blob name to create a virtual hierarchy. For example, the following list shows valid and unique blob names. Notice that a string can be valid as both a blob name and as a virtual directory name in the same container:

/a
/a.txt
/a/b
/a/b.txt

You can take advantage of the delimiter character when enumerating blobs.

注意:就在问这个问题之前，我发现这个问题可以回答我自己已经解决的问题或使用上述类:

Azure Container Name RegEx

How to validate Azure storage blob names

顺便问一下，有人知道 PowerShell 使用哪种风格的正则表达式吗？

Answer 1

您需要使用

^(?!.{1025})/?[^/]*[^/.](?:/[^/]*[^/.]){0,253}$
^(?=.{1,1024}$)/?[^/]*[^/.](?:/[^/]*[^/.]){0,253}$

请参阅regex demo .

详细信息:

• ^ - 字符串开头
• (?=.{1,1024}$) - 字符串应包含 1 到 1024 个字符
• (?!.{1025}) - 字符串包含的字符不能超过 1025 个
• /? - 可选的 /
• [^/]*[^/.] - 除 / 之外的零个或多个字符，然后是 / 以外的字符以及。
• (?:/[^/]*[^/.]){0,253} - 出现 0 到 253 次 /，后跟零个或多个除/ 然后是 / 和 之外的字符。
• $ - 字符串结尾。