curl --request POST \
  --url https://api.fincept.in/quantlib/models/short-rate/yield-curve \
  --header 'Content-Type: application/json' \
  --header 'X-API-Key: <api-key>' \
  --data '
{
  "model": "cir",
  "kappa": 0.2,
  "theta": 0.05,
  "sigma": 0.015,
  "r0": 0.025,
  "maturities": [
    0.5,
    1,
    2,
    3,
    5,
    7,
    10,
    20,
    30
  ]
}
'

import requests

url = "https://api.fincept.in/quantlib/models/short-rate/yield-curve"

payload = {
    "model": "cir",
    "kappa": 0.2,
    "theta": 0.05,
    "sigma": 0.015,
    "r0": 0.025,
    "maturities": [0.5, 1, 2, 3, 5, 7, 10, 20, 30]
}
headers = {
    "X-API-Key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'X-API-Key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    model: 'cir',
    kappa: 0.2,
    theta: 0.05,
    sigma: 0.015,
    r0: 0.025,
    maturities: [0.5, 1, 2, 3, 5, 7, 10, 20, 30]
  })
};

fetch('https://api.fincept.in/quantlib/models/short-rate/yield-curve', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.fincept.in/quantlib/models/short-rate/yield-curve",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'model' => 'cir',
    'kappa' => 0.2,
    'theta' => 0.05,
    'sigma' => 0.015,
    'r0' => 0.025,
    'maturities' => [
        0.5,
        1,
        2,
        3,
        5,
        7,
        10,
        20,
        30
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-API-Key: <api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.fincept.in/quantlib/models/short-rate/yield-curve"

	payload := strings.NewReader("{\n  \"model\": \"cir\",\n  \"kappa\": 0.2,\n  \"theta\": 0.05,\n  \"sigma\": 0.015,\n  \"r0\": 0.025,\n  \"maturities\": [\n    0.5,\n    1,\n    2,\n    3,\n    5,\n    7,\n    10,\n    20,\n    30\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("X-API-Key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.fincept.in/quantlib/models/short-rate/yield-curve")
  .header("X-API-Key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"model\": \"cir\",\n  \"kappa\": 0.2,\n  \"theta\": 0.05,\n  \"sigma\": 0.015,\n  \"r0\": 0.025,\n  \"maturities\": [\n    0.5,\n    1,\n    2,\n    3,\n    5,\n    7,\n    10,\n    20,\n    30\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.fincept.in/quantlib/models/short-rate/yield-curve")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["X-API-Key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"model\": \"cir\",\n  \"kappa\": 0.2,\n  \"theta\": 0.05,\n  \"sigma\": 0.015,\n  \"r0\": 0.025,\n  \"maturities\": [\n    0.5,\n    1,\n    2,\n    3,\n    5,\n    7,\n    10,\n    20,\n    30\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "success": true,
  "data": {
    "model": "cir",
    "yield_curve": [
      {
        "maturity": 0.5,
        "yield": 0.0275
      },
      {
        "maturity": 1,
        "yield": 0.0298
      },
      {
        "maturity": 2,
        "yield": 0.0335
      },
      {
        "maturity": 3,
        "yield": 0.0361
      },
      {
        "maturity": 5,
        "yield": 0.0399
      },
      {
        "maturity": 7,
        "yield": 0.0424
      },
      {
        "maturity": 10,
        "yield": 0.0453
      },
      {
        "maturity": 20,
        "yield": 0.0488
      },
      {
        "maturity": 30,
        "yield": 0.0495
      }
    ]
  }
}

{
  "detail": "Invalid API key"
}

{
  "detail": "Insufficient credits. This endpoint requires 5 credits. Current balance: 2 credits."
}

{
  "detail": [
    {
      "loc": [
        "body",
        "kappa"
      ],
      "msg": "field required",
      "type": "value_error.missing"
    }
  ]
}