在R中调用Google Maps API计算多地址对出行时间无结果求助

我是编程新手，已经尽可能跟着教程写代码，但所有地址对的出行时间计算都返回“无出行时间”，怀疑问题出在Google Maps API端而非代码本身。

我的代码 #

api_key <- 'IthinkIshouldNdtTellYOU'

desired_arrival_time <- as.POSIXct(paste(next_wednesday, "09:00:00"), tz = "America/New_York")
arrival_epoch_time <- as.numeric(desired_arrival_time)

get_travel_time <- function(origin, destination, api_key, arrival_time) {
  base_url <- "https://maps.googleapis.com/maps/api/directions/json?"
  query <- paste0("origin=", URLencode(origin),
              "&destination=", URLencode(destination),
              "&mode=transit",
              "&arrival_time=", arrival_time,
              "&key=", api_key)
  response <- GET(paste0(base_url, query))

  if (response$status_code == 200) {
    data <- fromJSON(rawToChar(response$content))
    if (length(data$routes) > 0) {
      travel_time <- data$routes[[1]]$legs[[1]]$duration$text
      return(travel_time)
    } else {
      return(NA)
    }
  } else {
    stop("API request failed with status code: ", response$status_code)
  }
}

address_pairs$travel_time <- NA

for (i in 1:nrow(address_pairs)) {
  travel_time_result <- try(
    get_travel_time(
      origin = address_pairs$OriginAdd[i],
      destination = address_pairs$DestinAdd[i],
      api_key = api_key,
      arrival_time = arrival_epoch_time
    ),
    silent = TRUE  # 设为TRUE避免直接打印错误信息
  )

  if (class(travel_time_result) == "try-error") {
    address_pairs$travel_time[i] <- NA
    print(paste("Error on row", i, ":", travel_time_result))
  } else {
    # 无错误时，检查函数是否返回有效数据
    if (!is.na(travel_time_result) && length(travel_time_result) > 0) {
      address_pairs$travel_time[i] <- travel_time_result
    } else {
      # 函数返回NA或空值时赋值NA
      address_pairs$travel_time[i] <- NA
      print(paste("No travel time returned for row", i))
    }
  }

  Sys.sleep(0.2) # 注意API调用频率限制
}

运行结果 #

No travel time returned for row 1208
No travel time returned for row 1209
No travel time returned for row 1210

地址样本 #

OriginAdd                           DestinAdd
365 Fifth Ave, Manhattan, New York  120 Schermerhorn St, Brooklyn, NY 11201
3280 46th Avenue, Queens, Corona, NY    265 E 161 St, Bronx, NY 10451
106-05 37 Avenue, Queens, New York .    125-01 Queens Blvd, Queens, NY 11415
3280 46th Street, Queens, NY    265 E 161 St, Bronx, NY 10451
475 48th Ave, Queens, New York 11109    100 Centre St, New York, NY 10013

疑问点 #

• 能看到API密钥被调用，但始终无结果；地址均为纽约市地址，Google Maps在该区域服务正常，RStudio查询耗时较长但无返回
• 看不懂Google Cloud账户里的内容，想确认该操作是否会产生费用，以及是否已经超出API配额
• 代码主要借助ChatGPT生成

内容的提问来源于stack exchange，提问作者David J.