R:从公司内部API获取PDF文档

我正在尝试使用R从API获取文档。感谢您在 this post .我已经部分成功地执行了上述步骤,但在获取文档内容的最后一步仍然失败:

1. 查找您感兴趣的文档归档(例如,为公司提出归档历史请求1)。在“links”:“document_metadata”:“link uri fragment here”字段中分析指向文档的链接的响应。

没问题:

library(httr)
library(jsonlite)
library(openssl)

### retrieving filing history ####
company_num = 'FC013908'
key = 'my_key'
fh_path = paste0('/company/', str_to_upper(company_num), "/filing-history")
fh_url <- modify_url("https://api.companieshouse.gov.uk/", path = fh_path)
fh_test <- GET(fh_url, authenticate(key, "")) #status_code = 200
fh_parsed <- jsonlite::fromJSON(content(fh_test, "text",encoding = "utf-8"), flatten = TRUE)
docs <- fh_parsed$items

完成。

2对于给定的文档,通过ch document api3请求文档元数据。分析响应以获得可用的文档(mime)类型以及到实际文档数据(文档uri片段)的链接。

这里没有问题:

md_meta_url = docs$links.document_metadata[1]  
key_pass <- paste0(key,":")
decoded_auth <- paste0('Basic ', base64_encode(key_pass))

md_test <- GET(md_meta_url,
               add_headers(Authorization = decoded_auth)
               )
md_test #status_code = 200!
md_parsed <- jsonlite::fromJSON(content(md_test, "text",encoding = "utf-8"), flatten = TRUE)

这样我就可以获得内容URL:

cont_url = md_parsed$links$document

请求实际文档9,指定mime类型(例如“application/pdf”)。

我在不遵循重定向的情况下执行此操作,如预期的那样,我使用 location 标题:

accept = 'application/pdf'
cont_test <- GET(cont_url, 
           add_headers(Authorization = decoded_auth,
                       Accept = accept),
           config(followlocation = FALSE)
)

final_url <- cont_test$headers$location

> final_url
[1] "https://s3-eu-west-1.amazonaws.com/document-api-images-prod/docs/LjBouRHeXXpIYAvqYIPWL06iXaliPz6Pucp1OXCXQhI/application-pdf?AWSAccessKeyId=ASIAJX7TVURFXZTY5DNQ&Expires=1529483765&Signature=uUQx6RTW7XBLqx4L6pYr5tOUySg%3D&x-amz-security-token=FQoDYXdzEP%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaDGxe7meYGe3OYhNwcSK3AwcVYJUXaUMf19oVO9s4qNPWN8AHjNNd5rrZhgE9YTkF1OmzyZSL5xHbls664kDP%2Bxd7dz9PIU5O1D%2BVxoDyoYcFiS6acDnO28KpfFE56lUZNfedf1jys%2FP0SJ8f%2F50Cbn93bfOlm0MZA9%2BQ2DYQvPfkWSvrDjMyCXHbu57gpZHjQKPNRTgzGXzUUCvFwREytGMM4eThhn4Glvvx%2FA8IiLbnsvgmEKw9iAj7KWIenhoJq3cTRytUpVeipLnQoBVLau8dFYkKdAHZaYM2Tlx0z6ObRb%2BGdm7W7eOVA1bFXuUXmUmnAHruDIwwLlgOVN2IJ9CxmJU22lY8jrEm%2BUivtrdp2oofn32PryBEJ8jJOg9cIpLbBBx%2FeOkng9zJwnZbute7Nmh%2BnaY2btsId6JjraFNsTvR%2B1qEZX9uuznUdJdqgVfTMj2gGrAmntwk0JAkILlvamzjWC%2F9vAqK7Xvt8aC6hlIMB2vdzTCU9Jf%2FrIMTClTJkk0BzBuvJ86t1l%2BXb4rF5Pab%2FegFpJ6nvZKqde%2F77wMMiTyG35EndmYx4AWqTIh9EofYwKZa9uciNvRT0E2%2BYnT5jZMo%2BdWn2QU%3D"

但是,当我试图

再次从Amazon请求此URI,并再次传递所需的内容类型。 我得到400个错误:

 final_test <- GET(final_url, 
                 add_headers(Authorization = decoded_auth,
                             Accept = accept
                             ))

> final_test
Response [https://s3-eu-west-1.amazonaws.com/document-api-images-prod/docs/LjBouRHeXXpIYAvqYIPWL06iXaliPz6Pucp1OXCXQhI/application-pdf?AWSAccessKeyId=ASIAJX7TVURFXZTY5DNQ&Expires=1529483765&Signature=uUQx6RTW7XBLqx4L6pYr5tOUySg%3D&x-amz-security-token=FQoDYXdzEP%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaDGxe7meYGe3OYhNwcSK3AwcVYJUXaUMf19oVO9s4qNPWN8AHjNNd5rrZhgE9YTkF1OmzyZSL5xHbls664kDP%2Bxd7dz9PIU5O1D%2BVxoDyoYcFiS6acDnO28KpfFE56lUZNfedf1jys%2FP0SJ8f%2F50Cbn93bfOlm0MZA9%2BQ2DYQvPfkWSvrDjMyCXHbu57gpZHjQKPNRTgzGXzUUCvFwREytGMM4eThhn4Glvvx%2FA8IiLbnsvgmEKw9iAj7KWIenhoJq3cTRytUpVeipLnQoBVLau8dFYkKdAHZaYM2Tlx0z6ObRb%2BGdm7W7eOVA1bFXuUXmUmnAHruDIwwLlgOVN2IJ9CxmJU22lY8jrEm%2BUivtrdp2oofn32PryBEJ8jJOg9cIpLbBBx%2FeOkng9zJwnZbute7Nmh%2BnaY2btsId6JjraFNsTvR%2B1qEZX9uuznUdJdqgVfTMj2gGrAmntwk0JAkILlvamzjWC%2F9vAqK7Xvt8aC6hlIMB2vdzTCU9Jf%2FrIMTClTJkk0BzBuvJ86t1l%2BXb4rF5Pab%2FegFpJ6nvZKqde%2F77wMMiTyG35EndmYx4AWqTIh9EofYwKZa9uciNvRT0E2%2BYnT5jZMo%2BdWn2QU%3D]
  Date: 2018-06-20 08:37
  Status: 400
  Content-Type: application/xml
  Size: 523 B
<BINARY BODY>

不用说,执行

browseURL(final_test$url)

退货 Access Denied 错误。我怀疑这可能与亚马逊的授权问题有点类似 here .有什么办法来解决这个最后的障碍吗?

谢谢!