Package httr2 for pipeable API for working with web APIs

Example 1: call US weather API

Code

pak::pkg_install('httr2')

https://api.weather.gov/points/38.8894,-77.0352

Code

library(httr2)
library(tidyverse)

API link

Code

NWS_base_url <- 'https://api.weather.gov'

NWS_response_link <- request(NWS_base_url) |> 
  req_url_path_append(
    'points',
    '38.8894,-77.0352'
  ) 

NWS_response_link

create response and check connection

Code

NWS_response=NWS_response_link|> req_perform()
NWS_response

get forecast hourly url from response

Code

NWS_response |> 
  resp_body_json() |> 
  glimpse()

Code

forecast_url <- NWS_response |> 
  resp_body_json() |> 
  pluck('properties', 'forecastHourly')

forecast_url

make forecast hourly response

Code

forecast_response <- request(forecast_url) |> 
  req_perform()

forecast_response |> 
  resp_body_json() |> 
  glimpse()

get forecast hourly data

Code

extracted_data <- forecast_response |> 
  resp_body_json() |> 
  pluck('properties', 'periods') |> 
  map_dfr( # iterates over each list and binds rows to a tibble
    \(x) {
      tibble(
        time = x |> pluck('startTime'),
        temp_F = x |> pluck('temperature'),
        rain_prob = x |> pluck('probabilityOfPrecipitation', 'value'),
        forecast = x |> pluck('shortForecast')
      )
    }
  )

extracted_data

Example 2 :openweathermap

https://home.openweathermap.org/

Code

pak::pkg_install('httr2')

Code

library(httr2)

create response

Code

library(keyring)
openweathermap_base_url <- 'https://api.openweathermap.org/data/2.5'

openweathermap_api_key=key_get("openweathermap_api_key")

city='Bangkok'

openweathermap_response_link <- request(openweathermap_base_url) |> 
  req_url_path_append(
    paste0('weather?q=',city,'&appid=',openweathermap_api_key,'&units=metric')
  ) 

openweathermap_response_link

Code

openweathermap_response=openweathermap_response_link|> req_perform()
openweathermap_response

get data from response

Code

openweathermap_response |> 
  resp_body_json() |> 
  glimpse()

Code

openweathermap_response |> 
  resp_body_json() |> 
  pluck('main', 'temp') 

a=openweathermap_response |> 
  resp_body_json() |> 
  pluck('weather') 

(a[[1]])$main

openweathermap_response |> 
  resp_body_json() |> 
  pluck('name') 

openweathermap_response |> 
  resp_body_json() |> 
  pluck('coord', 'lon') 

openweathermap_response |> 
  resp_body_json() |> 
  pluck('coord', 'lat')

London air_pollution:

http://api.openweathermap.org/data/2.5/air_pollution?lat=51.5085&lon=-0.1257&appid=625ae405e4f11b5b957af484b77fbd62

Reference

https://httr2.r-lib.org/

https://www.youtube.com/watch?v=8tilyqp4bZY

https://www.youtube.com/watch?v=hmtE4QGIOuk

https://openweathermap.org/current

--- title: "使用R httr2 调用API" subtitle: "Using R httr2 to call API" author: "Tony Duan" date: "2025-03-15" categories: - Tool - R execute: warning: false error: false eval: false image: 'logo.png' --- Package httr2 for pipeable API for working with web APIs # Example 1: call US weather API ```{r} pak::pkg_install('httr2') ``` https://api.weather.gov/points/38.8894,-77.0352 ```{r} library(httr2) library(tidyverse) ``` ## API link ```{r} NWS_base_url <- 'https://api.weather.gov' NWS_response_link <- request(NWS_base_url) |> req_url_path_append( 'points', '38.8894,-77.0352' ) NWS_response_link ``` ## create response and check connection ```{r} NWS_response=NWS_response_link|> req_perform() NWS_response ``` ## get forecast hourly url from response ```{r} NWS_response |> resp_body_json() |> glimpse() ``` ```{r} forecast_url <- NWS_response |> resp_body_json() |> pluck('properties', 'forecastHourly') forecast_url ``` ## make forecast hourly response ```{r} forecast_response <- request(forecast_url) |> req_perform() forecast_response |> resp_body_json() |> glimpse() ``` ## get forecast hourly data ```{r} extracted_data <- forecast_response |> resp_body_json() |> pluck('properties', 'periods') |> map_dfr( # iterates over each list and binds rows to a tibble \(x) { tibble( time = x |> pluck('startTime'), temp_F = x |> pluck('temperature'), rain_prob = x |> pluck('probabilityOfPrecipitation', 'value'), forecast = x |> pluck('shortForecast') ) } ) extracted_data ``` # Example 2 :openweathermap https://home.openweathermap.org/ ```{r} pak::pkg_install('httr2') ``` ```{r} library(httr2) ``` ## create response ```{r} library(keyring) openweathermap_base_url <- 'https://api.openweathermap.org/data/2.5' openweathermap_api_key=key_get("openweathermap_api_key") city='Bangkok' openweathermap_response_link <- request(openweathermap_base_url) |> req_url_path_append( paste0('weather?q=',city,'&appid=',openweathermap_api_key,'&units=metric') ) openweathermap_response_link ``` ```{r} openweathermap_response=openweathermap_response_link|> req_perform() openweathermap_response ``` ## get data from response ```{r} openweathermap_response |> resp_body_json() |> glimpse() ``` ```{r} openweathermap_response |> resp_body_json() |> pluck('main', 'temp') a=openweathermap_response |> resp_body_json() |> pluck('weather') (a[[1]])$main openweathermap_response |> resp_body_json() |> pluck('name') openweathermap_response |> resp_body_json() |> pluck('coord', 'lon') openweathermap_response |> resp_body_json() |> pluck('coord', 'lat') ``` London air_pollution: http://api.openweathermap.org/data/2.5/air_pollution?lat=51.5085&lon=-0.1257&appid=625ae405e4f11b5b957af484b77fbd62 # Reference https://httr2.r-lib.org/ https://www.youtube.com/watch?v=8tilyqp4bZY https://www.youtube.com/watch?v=hmtE4QGIOuk https://openweathermap.org/current