Question

我需要在nodejs中解析Azure Blob URI并提取存储帐户名，容器名和blob名。

我调查了azure-sdk-for-node和azure-storage-node但我找不到这样做的方法。

如果Blob URI无效，我也想检测一下，所以可能正则表达式（如果可能的话）是一个很好的方法。

Blob URI的一些示例：

https://myaccount.blob.core.windows.net/mycontainer/myblob
http://myaccount.blob.core.windows.net/myblob
https://myaccount.blob.core.windows.net/$root/myblob

Answer 1

通过关注specification from Azure，我想出了以下函数（gist），它使用正则表达式来解析blob uri，如果blob uri无效，它也会抛出错误。

存储帐户名称和容器名称应该完全正确/精确，只有blob名称我有点松散，因为定义起来比较复杂。

/**
 * Validates and parses given blob uri and returns storage account, 
 * container and blob names.
 * @param {string} blobUri - Valid Azure storage blob uri.
 * @returns {Object} With following properties:
 *   - {string} storageAccountName
 *   - {string} containerName
 *   - {string} blobName
 * @throws {Error} If blobUri is not valid blob uri.
 */
const parseAzureBlobUri = (blobUri) => {
  const ERROR_MSG_GENERIC = 'Invalid blob uri.'

  const storageAccountRegex = new RegExp('[a-z0-9]{3,24}')
  const containerRegex = new RegExp('[a-z0-9](?!.*--)[a-z0-9-]{1,61}[a-z0-9]')
  const blobRegex = new RegExp('.{1,1024}')  // TODO: Consider making this one more precise.
  const blobUriRegex = new RegExp(
    `^http[s]?:\/\/(${ storageAccountRegex.source })\.blob.core.windows.net\/`
    + `(?:(\$root|(?:${ containerRegex.source }))\/)?(${ blobRegex.source })$`
  )
  const match = blobUriRegex.exec(blobUri)
  if (!match) throw Error(ERROR_MSG_GENERIC)

  return {
    storageAccountName: match[1],
    // If not specified, then it is implicitly root container with name $root.
    containerName: match[2] || '$root',
    blobName: match[3]
  }
}

Answer 2

您可以使用url.parse。

我的主要原因是避免使用正则表达式，它也更容易理解，阅读和修改。

以下是示例代码：

const url = require('url')

const parseAzureBlobUri = (blobUrl) => {
    let uri = url.parse(blobUrl)

    // Extract the storage account name
    let storageAccountName = uri.hostname.split('.')[0]        

    // Remove the 1st trailing slash then extract segments
    let segments = uri.pathname.substring(1).split('/')

    // If only one segment, this is the blob name
    if(segments.length === 1){
        return {
            storageAccountName,
            containerName: '$root',
            blobName: segments[0]
        }
    }

    // get the container name
    let containerName = segments[0]

    // Remove the containername from the segments
    segments.shift()

    return {
        storageAccountName,
        containerName,
        blobName: segments.join('/')
    }
}

如何在nodejs / javascript中解析Azure Blob URI？

2 个答案: