sdk/R/R/HttpRequest.R

   1 source("./R/custom_classes.R")
   2
   3 HttpRequest <- setRefClass(
   4
   5     "HttrRequest",
   6
   7     fields = list(
   8         send_method         = "character",
   9         server_base_url     = "character",
  10         server_relative_url = "character",
  11         auth_token          = "character",
  12         allowed_methods     = "list",
  13         query_filters       = "ANY",
  14         response_limit      = "ANY",
  15         query_offset        = "ANY"
  16     ),
  17
  18     methods = list(
  19         initialize = function(method,
  20                               token,
  21                               base_url,
  22                               relative_url,
  23                               filters = NULL,
  24                               limit = 100,
  25                               offset = 0)
  26         {
  27             send_method         <<- method
  28             auth_token          <<- token
  29             server_base_url     <<- base_url
  30             server_relative_url <<- relative_url
  31             query_filters       <<- filters
  32             response_limit      <<- limit
  33             query_offset        <<- offset
  34         },
  35
  36         execute = function()
  37         {
  38             http_method <- switch(send_method,
  39                                   "GET"    = .self$getRequest,
  40                                   "POST"   = .self$postRequest,
  41                                   "PUT"    = .self$putRequest,
  42                                   "DELETE" = .self$deleteRequest,
  43                                   "PATCH"  = .self$pathcRequest)
  44             http_method()
  45         },
  46
  47         getRequest = function()
  48         {
  49             requestHeaders <- httr::add_headers(Authorization = .self$getAuthHeader())
  50             requestQuery   <- .self$generateQuery()
  51             url            <- paste0(server_base_url, server_relative_url, requestQuery)
  52
  53             server_data <- httr::GET(url    = url,
  54                                      config = requestHeaders)
  55         },
  56
  57         #Todo(Fudo): Try to make this more generic
  58         postRequest = function()
  59         {
  60             #Todo(Fudo): Implement this later on.
  61             print("POST method")
  62         },
  63
  64         putRequest = function()
  65         {
  66             #Todo(Fudo): Implement this later on.
  67             print("PUT method")
  68         },
  69
  70         deleteRequest = function()
  71         {
  72             #Todo(Fudo): Implement this later on.
  73             print("DELETE method")
  74         },
  75
  76         pathcRequest = function()
  77         {
  78             #Todo(Fudo): Implement this later on.
  79             print("PATCH method")
  80         },
  81
  82         getAuthHeader = function()
  83         {
  84             auth_method <- "OAuth2"
  85             auth_header <- paste(auth_method, auth_token)
  86         },
  87
  88         generateQuery = function()
  89         {
  90             #Todo(Fudo): This function is a mess, refactor it
  91             finalQuery <- "?alt=json"
  92
  93             if(!is.null(query_filters))
  94             {
  95                 filters <- sapply(query_filters, function(filter)
  96                 {
  97                     if(length(filter) != 3)
  98                         stop("Filter list must have exacthey 3 elements.")
  99
 100                     attributeAndOperator = filter[c(1, 2)]
 101                     filterList = filter[[3]]
 102                     filterListIsPrimitive = TRUE
 103                     if(length(filterList) > 1)
 104                         filterListIsPrimitive = FALSE
 105
 106                     attributeAndOperator <- sapply(attributeAndOperator, function(component) {
 107                         component <- paste0("\"", component, "\"")
 108                     })
 109
 110                     filterList <- sapply(unlist(filterList), function(filter) {
 111                         filter <- paste0("\"", filter, "\"")
 112                     })
 113
 114                     filterList <- paste(filterList, collapse = ",+")
 115
 116                     if(!filterListIsPrimitive)
 117                         filterList <- paste0("[", filterList, "]")
 118
 119                     filter <- c(attributeAndOperator, filterList)
 120
 121                     queryParameter <- paste(filter, collapse = ",+")
 122                     queryParameter <- paste0("[", queryParameter, "]")
 123
 124                 })
 125
 126                 filters <- paste(filters, collapse = ",+")
 127                 filters <- paste0("[", filters, "]")
 128
 129                 encodedQuery <- URLencode(filters, reserved = T, repeated = T)
 130
 131                 finalQuery <- paste0(finalQuery, "&filters=", encodedQuery)
 132
 133                 #Todo(Fudo): This is a hack for now. Find a proper solution.
 134                 finalQuery <- stringr::str_replace_all(finalQuery, "%2B", "+")
 135             }
 136
 137             if(!is.null(response_limit))
 138             {
 139                 if(!is.numeric(response_limit))
 140                     stop("Limit must be a numeric type.")
 141
 142                 finalQuery <- paste0(finalQuery, "&limit=", response_limit)
 143             }
 144
 145             if(!is.null(query_offset))
 146             {
 147                 if(!is.numeric(query_offset))
 148                     stop("Offset must be a numeric type.")
 149
 150                 finalQuery <- paste0(finalQuery, "&offset=", query_offset)
 151             }
 152
 153             finalQuery
 154         }
 155     )
 156 )