invoke_function in aws lambda runtime: UnrecognizedClientException

[bneigher]

Please specify whether your issue is about:

• [x] a possible bug
• [ ] a question about package functionality
• [ ] a suggested code or documentation change, improvement to the code, or feature request

## load package
library("aws.lambda")

Sys.setenv("AWS_DEFAULT_REGION" = "us-west-2") # Needed for me to do manually for some reason
Sys.setenv(TZ = "GMT")

handler <- function(...) {
  lambdaFunction = paste(
    Sys.getenv("ENVIRONMENT"), Sys.getenv("LAMBDA_FN_NAME"),
    sep = "-"
  )
  
  payload = list(user_id = "1", event = "events.invite.email")
  result <- invoke_function(
    name = lambdaFunction,
    payload = toJSON(payload, auto_unbox = TRUE),
    type = "RequestResponse",
    log = "None"
  )
  return(fromJSON(toJSON(list(code = 0))))
}

Session Info:

R version 3.6.1 (2019-07-05)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Amazon Linux AMI 2018.03

Matrix products: default
BLAS:   /opt/R/lib/libRblas.so
LAPACK: /opt/R/lib/libRlapack.so

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
 [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
 [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
 [7] LC_PAPER=en_US.UTF-8       LC_NAME=C                 
 [9] LC_ADDRESS=C               LC_TELEPHONE=C            
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] lubridate_1.7.4   feather_0.3.5     aws.lambda_0.1.6  aws.s3_0.3.12    
[5] data.table_1.12.2 jsonlite_1.6      httr_1.4.1        logging_0.10-108 

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.2          magrittr_1.5        xml2_1.2.2         
 [4] hms_0.5.1           aws.signature_0.5.2 R6_2.4.0           
 [7] rlang_0.4.0         stringr_1.4.0       tools_3.6.1        
[10] digest_0.6.20       tibble_2.1.3        crayon_1.3.4       
[13] base64enc_0.1-3     vctrs_0.2.0         curl_4.1           
[16] zeallot_0.1.0       stringi_1.4.3       compiler_3.6.1     
[19] pillar_1.4.2        backports_1.1.4     pkgconfig_2.0.2 

Note I am using a custom runtime in aws lambda to execute this code. Communication to aws.s3 works great and I know the correct roles are being assumed.

This works fine when running on my local machine which makes me think there is something wrong with how this package performs specifically when running on the aws lambda runtime environment