Http Module

HTTP client for making network requests.

The Http module uses a request-as-data pattern: functions like Http.get return a Request record (pure data), and only Http.send performs the side effect. Requests are composable via the pipe operator |>.

Common patterns

import Http

-- GET request with headers
let response = Http.get "https://api.example.com/users"
    |> Http.setHeader "Accept" "application/json"
    |> Http.setTimeout 5000
    |> Http.send

-- POST with JSON body
let result = Http.post "https://api.example.com/users"
    |> Http.setJsonBody { name = "Alice" }
    |> Http.send

Security

Variable	Effect
`KEEL_HTTP_DISABLED=0`	Enable HTTP requests (disabled by default)
`KEEL_HTTP_ALLOWED_HOSTS=a.com,b.com`	Restrict to listed domains

Functions

Request construction

`Http.get`

String -> Request

Create a GET request for the given URL.

Example:

import Http

Http.get "https://example.com"

Try it

Notes: Returns a Request record. Use Http.send to execute.

See also: Http.post, Http.send

`Http.post`

String -> Request

Create a POST request for the given URL.

Example:

import Http

Http.post "https://example.com/api"

Try it

See also: Http.get, Http.setBody, Http.setJsonBody

`Http.put`

String -> Request

Create a PUT request for the given URL.

Example:

import Http

Http.put "https://example.com/api/1"

Try it

See also: Http.post, Http.patch

`Http.patch`

String -> Request

Create a PATCH request for the given URL.

Example:

import Http

Http.patch "https://example.com/api/1"

Try it

See also: Http.put, Http.post

`Http.delete`

String -> Request

Create a DELETE request for the given URL.

Example:

import Http

Http.delete "https://example.com/api/1"

Try it

See also: Http.get

`Http.request`

String -> String -> Request

Create a request with a custom HTTP method.

Example:

import Http

Http.request "OPTIONS" "https://example.com"

Try it

Notes: First argument is the HTTP method, second is the URL.

See also: Http.get, Http.post

Request modification

`Http.setHeader`

String -> String -> Request -> Request

Add a header to the request.

Example:

import Http
Http.get "https://example.com" |> Http.setHeader "Accept" "application/json"

Try it

Notes: Request is the last argument for pipe-friendliness.

See also: Http.setHeaders

`Http.setHeaders`

[(String, String)] -> Request -> Request

Add multiple headers to the request.

Example:

import Http

Http.get "https://example.com"
    |> Http.setHeaders [("Accept", "text/html"), ("X-Custom", "value")]

Try it

See also: Http.setHeader

`Http.setBody`

String -> Request -> Request

Set the request body as a string.

Example:

import Http

Http.post "https://example.com/api"
    |> Http.setBody "data"

Try it

See also: Http.setJsonBody

`Http.setJsonBody`

a -> Request -> Request

Set the request body as JSON-encoded value and add Content-Type header.

Example:

import Http
Http.post "https://example.com/api" |> Http.setJsonBody { name = "Alice" }

Try it

Notes: Automatically sets Content-Type to application/json.

See also: Http.setBody

`Http.setTimeout`

Int -> Request -> Request

Set the request timeout in milliseconds.

Example:

import Http

Http.get "https://example.com"
    |> Http.setTimeout 5000

Try it

Notes: Default timeout is 30000ms (30 seconds).

`Http.setQueryParam`

String -> String -> Request -> Request

Add a query parameter to the request URL.

Example:

import Http

Http.get "https://example.com"
    |> Http.setQueryParam "page" "1"

Try it

Execution

`Http.send`

Request -> Result Response HttpError

Send the HTTP request and return a Result with the Response or an error.

Example:

import Http

Http.get "https://example.com"
    |> Http.send

Try it

Notes: This is the only function that performs IO. Requires KEEL_HTTP_DISABLED=0.

See also: Http.responseJson

`Http.responseJson`

Response -> Result a HttpError

Parse the response body as JSON.

Example:

import Http

let response =
    { status = 200, body = "{}" }

response
    |> Http.responseJson

Try it

Notes: Returns Err if the body is not valid JSON.

See also: Http.send, Http.responseText, Json.parse

Other

`Http.responseText`

Response -> String

Extract the response body as a raw string.

Example:

import Http

Http.get "https://example.com"
    |> Http.send
    |> Result.map Http.responseText

Try it

Notes: Returns the raw body string without any parsing. Use Http.responseJson to parse as JSON.

See also: Http.responseJson, Http.send