How to interpolate string into RCurl's URL? [duplicate] - r

Is there any way to assign variable to a http GET request form using rcurl?
eg:
getURL("https://testme.com/www//LoginService/login?login=xyz&password=<variable>")
I need to pass the value of password as a variable.
Regards ...

What about using paste0?
library("RCurl")
mypw <- "may1989"
basereq <- "https://testme.com/www//LoginService/login?login=xyz&password="
fullreq <- paste0( basereq, mypw, "/" )
So the full request looks like:
fullreq
## [1] "https://testme.com/www//LoginService/login?login=xyz&password=may1989/"
which you can curl in:
getURL(fullreq)

Try httr:
library(httr)
GET("https://testme.com/www/LoginService/login",
query = list(login = "xyz", password = variable)
)
httr will automatically escape variable as needed.

Related

paste0() adds an escape forward backslash in call to API?

I need to dynamically make a call to an API using the following format:
auth_secret <- paste0("Bearer ", secret)
headers = c(
`Authorization` = auth_secret,
`Notion-Version` = '2022-02-22',
`Content-Type` = 'application/json' )
res <- httr::PATCH(url = paste0('https://api.notion.com/v1/pages/', id),
httr::add_headers(.headers = headers),
body = payload,
encode = "json")
d <- httr::content(res)
This payload works:
payload <- "{\"properties\":{\"Project\":{\"relation\":[{\"id\":\"1d148a9e-783d-47a7-b3e8-2d9c34210355\"}]}}}"
But if I want to create it dynamically, using a paste0 (so it is inside of a function), I get some backslashes added before and after:
payload <- paste0('"{\"properties\":{\"',property_name,'\":{\"relation\":[{\"id\":\"',value,'\"}]}}}"')
print(payload)
"\"{\"properties\":{\"%7CAK%5E\":{\"relation\":[{\"id\":\"8cb9519e72ca4bbe9e0448807acb8e10\"}]}}}\""
I presume this is due to some weird escape character being added but have run out of ideas. I've added two \ and have gotten same issue. Call fails as JSON is not passed correctly. Is there a workaround?
This is obviously something to do with the fact that paste0 is escaping even the double quotes you do not want to escape.
No doubt someone is aware of the details. However, when I get weird stuff with paste0, I just use sprintf, which seems to work in this case:
property_name = "Projects"
value = "1d148a9e-783d-47a7-b3e8-2d9c34210355"
payload <- sprintf(
"{\"properties\":{\"%s\":{\"relation\":[{\"id\":\"%s\"}]}}}",
property_name, value
)
print(payload)
# [1] "{\"properties\":{\"Projects\":{\"relation\":[{\"id\":\"1d148a9e-783d-47a7-b3e8-2d9c34210355\"}]}}}"

How to read R Plumber function parameters data from another script?

Let say there is R code for REST API based on using the "plumber" package.
Here is a function from it.
#' Date of sale
#' #get /date_of_sale
#' #param auth_key Auth key
#' #param user_id User ID
#' #example https://company.com/date_of_sale?auth_key=12345&user_id=6789
function(auth_key, user_id) {
# ...
}
Let say there is another R script that uses API request to this server like
api_string <- "https://company.com/date_of_sale?auth_key=12345&user_id=6789"
date_of_sale <- jsonlite::fromJSON(api_string)
Is it possible to get a description of the parameters "auth_key" and "user_id" in the second script to have a full explanation of what means each parameter? For example, get for "auth_key" a string "Auth key"? Or how it will be possible to get access to function "date_of_sale" metadata at all?
Thanks for any ideas?
Using a file plumber.R with content as you provided. Assuming it is in the working directory.
In R
pr_read <- plumber::pr("plumber.R")
spec <- pr_read$getApiSpec()
spec$paths$`/date_of_sale`$get$parameters
spec is an R list with the same structure as an OpenAPI document.
If you do not have access to API plumber file but your API is running somewhere you have access to.
spec <- jsonlite::fromJSON("{api_server}/openapi.json", simplifyDataFrame = FALSE)
spec$paths$`/date_of_sale`$get$parameters
Again this follows the OpenAPI documentation standards.
Since this is an API GET request you can not access the description of the variable unless you explicitly include it in the API response.
I've learned some R script purely for this question, my guess is this is how you've prepared your JSON API response.
You can do something like this in your JSON request.
library(rjson)
auth_key <- "some_key";
user_id <- "340";
x <- list(auth_key = list(
type = typeof(auth_key),
lenght = length(auth_key),
attributes = attributes(auth_key),
string = auth_key
),
user_id = list(
type = typeof(user_id),
lenght = length(user_id),
attributes = attributes(user_id),
string = user_id
),
data = "your_data"
);
#x
json <- toJSON(x, indent=0, method="C" )
fromJSON( json )
You might want to look a these.
https://stat.ethz.ch/R-manual/R-devel/library/base/html/typeof.html
https://ramnathv.github.io/pycon2014-r/learn/structures.html https://rdrr.io/cran/rjson/man/toJSON.html https://www.rdocumentation.org/packages/base/versions/3.6.2/topics/attributes

How to Change Part of URL With a Function Input in R?

Let's say we have a url in R like:
url <- 'http://google.com/maps'
And the objective is to change the 'maps' part of it. I'd like to write a function where basically I can just input something (e.g. 'maps', 'images'), etc., and the relevant part of the url will automatically change to reflect what I'm typing in.
Is there a way to do this in R, where part of the url can be changed by typing something into a function?
Thanks!
You have to store the part you type into a variable and paste this to the base URL:
base_url <- "http://google.com/"
your_extension <- "maps"
paste0(base_url, your_extension)
[1] "http://google.com/maps"
If you have to start with a fixed URL, use sub to replace the last part:
sub("\\w+$", 'foo', url)
# "http://google.com/foo"
You can use dirname to remove the last part of the URL and paste it with additional custom string.
change_url_part <- function(base_url, string) {
paste(dirname(base_url), string, sep = '/')
}
change_url_part('http://google.com/maps', 'images')
#[1] "http://google.com/images"

Running a POST request to get a Service Ticket inside a for loop

I'm working with the NIH/NLM REST API and attempting to programmatically pull lots of data at once. I've never worked with an API that validates with Service Tickets (TGT and ST) instead of OAUTH, that need to be refreshed for every GET request you make, so I'm not sure if I"m even going about this the right way. Any help much appreciated.
Here's the code I currently have:
library(httr)
library(jsonlite)
library(xml2)
UTS_API_KEY <- 'MY API KEY'
# post to the CAS endpoint
response <- POST('https://utslogin.nlm.nih.gov/cas/v1/api-key', encode='form', body=list(apikey = 'MY API KEY'))
# print out the status_code and content_type
status_code(response)
headers(response)$`content-type`
doc <- content(response)
action_uri <- xml_text(xml_find_first(doc, '//form/#action'))
action_uri
# Service Ticket
response <- POST(action_uri, encode='form', body=list(service = 'http://umlsks.nlm.nih.gov'))
ticket <- content(response, 'text')
ticket #this is the ST I need for every GET request I make
# build search_uri using the paste function for string concatenation
version <- 'current'
search_uri <- paste('https://uts-ws.nlm.nih.gov/rest/search/', version, sep='')
# pass the the query params into httr GET to get the response
query_string <- 'diabetic foot'
response <- GET(search_uri, query=list(ticket=ticket, string=query_string))
## print out some of the results
search_uri
status_code(response)
headers(response)$`content-type`
search_results_auto_parsed <- content(response)
search_results_auto_parsed
class(search_results_auto_parsed$result$results)
search_results_data_frame <- fromJSON(content(response,'text'))
search_results_data_frame
This code works perfectly for just a handful of GET requests, however, I'm attempting to pull 300-something medical terms. For example, in query string, I'd like to loop through an array of strings (e.g., "diabetes", "blood pressure", "cardiovascular care", "EMT", etc.). I'd need to make the POST request and pass the ST into the GET parameter for every string in the array.
I've played around with this code:
for (i in 1:length(Entity_Subset$Entities)){
ent = Entity_Subset$Entities[i] #Entities represents my df of strings
url <- paste(' https://uts-ws.nlm.nih.gov/rest/search/current?string=',
ent,'&ticket=', sep = "")
print(url)
}
But haven't had much luck piecemealing together the POST and GET requests after putting the strings into the (GET) HTTPS request.
Sidebar: I also attempted writing some pre-scripts in Postman, but oddly the Service Ticket doesn't return as JSON (no key-value pair to grab and pass). Just plain text.
Thank you for any advice you can provide!
I think you can simply wrap both POST and GET requests in a function. Then, lapply that function to a list of characters.
library(httr)
library(jsonlite)
library(xml2)
fetch_data <- function(query_string = 'diabetic foot', UTS_API_KEY = 'MY API KEY', version = 'current') {
response <- POST('https://utslogin.nlm.nih.gov/cas/v1/api-key', encode='form', body=list(apikey = UTS_API_KEY))
# print out the status_code and content_type
message(status_code(response), "\n", headers(response)$`content-type`)
action_uri <- xml_text(xml_find_first(content(response), '//form/#action')); message(action_uri)
# Service Ticket
response <- POST(action_uri, encode = 'form', body=list(service = 'http://umlsks.nlm.nih.gov'))
ticket <- content(response, 'text'); message(ticket)
# build search_uri using the paste function for string concatenation
search_uri <- paste0('https://uts-ws.nlm.nih.gov/rest/search/', version)
# pass the the query params into httr GET to get the response
response <- GET(search_uri, query=list(ticket=ticket, string=query_string))
## print out some of the results
message(search_uri, "\n", status_code(response), "\n", headers(response)$`content-type`)
fromJSON(content(response, 'text'))
}
# if you have a list of query strings, then
lapply(Entity_Subset$Entities, fetch_data, UTS_API_KEY = "blah blah blah")
# The `lapply` above is logically equivalent to
result <- vector("list", length(Entity_Subset$Entities))
for (x in Entity_Subset$Entities) {
result[[x]] <- fetch_data(x, "blah blah blah")
}

Problem with authorization to COINAPI REST API with custom header and key in R

I would like to connect to COINAPI resources. They provide two types of authorization. https://docs.coinapi.io/#authorization
Custom authorization header named X-CoinAPI-Key
Query string parameter named apikey
When I am using the first method, it is working with basic requests. But respond with an error in more advanced.
endpoint<-"/v1/exchangerate/BTC?apikey="
But when I specify endpoint like this:
endpoint <- "/v1/trades/BITSTAMP_SPOT_BTC_USD/history?time_start=2016-01-01T00:00:00/?apikey="
I got error 401.
The second method is not working so far, I do not really understand how can I specify custom header name here.
I need to get data from here:
https://rest.coinapi.io/v1/ohlcv/BTC/USD/history?period_id=1DAY&time_start=2017-01-02T00:00:00.0000000Z&time_end=2019-01-02T00:00:00.0000000Z&limit=10000&include_empty_items=TRUE
I would appreciate any help on this issue.
1. method (working)
library(httr)
library(jsonlite)
base <- "https://rest.coinapi.io"
endpoint <- "/v1/exchangerate/BTC?apikey="
api_key <- <KEY>
call <- paste0(base, endpoint, api_key)
call
get_prices <- GET(call)
http_status(get_prices)
class(get_prices)
get_prices_text <- content(get_prices, "text", encoding = 'UTF-8')
get_prices_json <- fromJSON(get_prices_text, flatten = TRUE)
names(get_prices_json)
get_prices_json$asset_id_base
head(get_prices_json$rates)
data<-as.data.frame(get_prices_json)
2. method (not working)
key<-<KEY>
GET(
url = sprintf("https://rest.coinapi.io/v1/exchangerate/BTC"),
add_headers(`Authorization` = sprintf("X-CoinAPI-Key: ", key))
) -> res
http_status(res)
From reading the examples in the documentation, it looks like it's just looking for a simple header, not an "Authorization" header specifically. Try this
GET(
url = sprintf("https://rest.coinapi.io/v1/exchangerate/BTC"),
add_headers(`X-CoinAPI-Key` = key)
) -> res
http_status(res)

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