fael.gabriel
Need to create a body for Tesla with duplicate map keys
Hey all,
I am using Tesla to make a POST request and I need to post a body with duplicate keys, like this map:
%{
"id[]" => "1",
"id[]" => "2",
"id[]" => "3"
}
The problem is that when I try to create this map, it does not keep the duplicated keys id[], so how can I generate this kind of body with a list of duplicated keys?
What I have so far:
I have this map as input:
ids = %{
"1" => "any-value",
"2" => "any-value",
"3" => "any-value"
}
and I am trying to convert that to this output to post as the body in Tesla:
%{
"id[]" => "1",
"id[]" => "2",
"id[]" => "3"
}
with this code:
ids |> Enum.map(fn {id, _} -> %{"id[]" => id} end) |> Enum.reduce(&Map.merge/2)
but as I said this keeps only one id[] in the map, e.g: %{"id[]" => "1"}.
Does anyone have any thoughts on how can I achieve this?
Thanks in advance,
Rafael.
Most Liked
chulkilee
What’s the format of the body? Seems like you want application/x-www-form-urlencoded, so time to use Tesla.Middleware.FormUrlencoded, which uses URI.encode_query/1 under the hood.
client = Tesla.client([
{Tesla.Middleware.BaseUrl, "https://httpbin.org/"},
Tesla.Middleware.EncodeFormUrlencoded,
Tesla.Middleware.DecodeJson,
Tesla.Middleware.Logger
])
client |> Tesla.post("/post", [{"id[]", "1"},{"id[]", "2"}])
Output excerpt:
>>> REQUEST >>>
(no query)
content-type: application/x-www-form-urlencoded
id%5B%5D=1&id%5B%5D=2
<<< RESPONSE <<<
{
"args": {},
"data": "",
"files": {},
"form": {
"id[]": [
"1",
"2"
]
},
"headers": {
"Content-Length": "21",
"Content-Type": "application/x-www-form-urlencoded",
"Host": "httpbin.org",
},
"json": null,
"url": "https://httpbin.org/post"
}
Please note
[]notation to take values into array is not a standard but just common convention. e.g. See Plug.Conn.Query- Elixir’s URI.decode_query returns a map, which is convenient but it’s wrong to use parse a string in urlencoded form, since WHATWG defines it as list of key/value, not map!
For that exact reason I wrote whatwg/lib/whatwg/url/www_form_urlencoded.ex at main · chulkilee/whatwg · GitHub a while ago.
Popular in Questions
Other popular topics
Latest on Elixir Forum
Sponsor Spotlight
Build Elixir applications with speed and confidence.
Categories:
Sub Categories:
Forums
Our Sponsors
Build Elixir applications with speed and confidence.
Supporting innovation across the BEAM ecosystem.
We build reliable cloud platforms for business-critical systems.
Catch errors, track performance, monitor hosts and more.
Real-time error tracking, performance insights, and observability for devs.
Practical resources that improve the lives of professional developers.
Producing high quality Elixir screencasts since 2017.
The deployment platform built for Elixir: PaaS ease, VPS control.
Courses that'll move you from confusion to "Aha, now I get it!"