通过R查询AWS Pricing API

Question

我尝试通过R查询AWS pricing端点，但收到403错误。

我到处寻找在R中运行AWS端点的通用示例，但真的找不到太多。有什么想法吗？

library(aws.signature)
library(httr)

# validate arguments and setup request URL
current <- Sys.time()
d_timestamp <- format(current, "%Y%m%dT%H%M%SZ", tz = "UTC")

hdrs <- list(`Content-Type` = "application/x-www-form-urlencoded",
             Host = "apigateway.us-east-1.amazonaws.com",
             `x-amz-date` = d_timestamp)

params <- signature_v4_auth(
  datetime = d_timestamp,
  region = "us-east-1",
  service = "execute-api",
  verb = "GET",
  action = "iMetaAPI",
  query_args = list(),
  canonical_headers = hdrs,
  request_body = "json",
  key = "***********",
  secret = "***************",
  session_token = NULL,
  query = FALSE,
  algorithm = "AWS4-HMAC-SHA256",
  verbose = TRUE)


a <- GET("https://api.pricing.us-east-1.amazonaws.com",
         query = params)

Answer 1

您也可以使用paws程序包查询亚马逊网络服务价目表服务应用编程接口。Paws提供了从R内部访问全套亚马逊网络服务的权限，类似于boto3，Python的官方AWS SDK，为Python用户提供的服务。

在下面的示例中，我使用一个定价客户端来获取亚马逊SageMaker当前可用的所有位置。我使用purrr包来解析响应。我将我的亚马逊网络服务凭证(AWS_ACCESS_KEY_ID、AWS_SECRET_ACCESS_KEY)存储在.Renviron中，这就是您在下面的代码中看不到它们的原因。

library(paws)
library(purrr)

# Create pricing client
pricing_client <- pricing()

# Fetch metadata information of the SageMaker service
sm_metadata <- pricing_client$describe_services(
   ServiceCode = "AmazonSageMaker")

str(sm_metadata)
#> List of 3
#>  $ Services     :List of 1
#>   ..$ :List of 2
#>   .. ..$ ServiceCode   : chr "AmazonSageMaker"
#>   .. ..$ AttributeNames: chr [1:34] "productFamily" "automaticLabel" "volumeType" "memory" ...
#>  $ FormatVersion: chr "aws_v1"
#>  $ NextToken    : chr(0) 

# Store available SageMaker service attribute names in a vector
sm_attributes <- sm_metadata %>% 
  pluck("Services", 1,  "AttributeNames")

tail(sm_attributes)
#> [1] "groupDescription" "currentGeneration" "integratingService" "location" "processorArchitecture" "operation" 

# Fetch all locations where the SageMaker service is available
sm_locations <-  pricing_client$get_attribute_values("AmazonSageMaker", "location") %>% 
  .[["AttributeValues"]] %>% 
  map_chr(function(x) x[["Value"]])

sm_locations
#> [1] "AWS GovCloud (US-West)"    "Any"                       "Asia Pacific (Hong Kong)" 
#> [4] "Asia Pacific (Mumbai)"     "Asia Pacific (Seoul)"      "Asia Pacific (Singapore)" 
#> [7] "Asia Pacific (Sydney)"     "Asia Pacific (Tokyo)"      "Canada (Central)"         
#> [10] "EU (Frankfurt)"            "EU (Ireland)"              "EU (London)"              
#> [13] "EU (Paris)"                "EU (Stockholm)"            "Middle East (Bahrain)"    
#> [16] "South America (Sao Paulo)" "US East (N. Virginia)"     "US East (Ohio)"           
#> [19] "US West (N. California)"   "US West (Oregon)"