Prepare a sponsored transaction
curl --request POST \
--url https://harness.chance.cc/api/v1/gas/prepare \
--header 'Content-Type: application/json' \
--header 'x-api-key: <api-key>' \
--data '
{
"scanId": "<string>",
"calls": [
{
"to": "<string>",
"data": "<string>",
"value": "<string>"
}
]
}
'import requests
url = "https://harness.chance.cc/api/v1/gas/prepare"
payload = {
"scanId": "<string>",
"calls": [
{
"to": "<string>",
"data": "<string>",
"value": "<string>"
}
]
}
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({
scanId: '<string>',
calls: [{to: '<string>', data: '<string>', value: '<string>'}]
})
};
fetch('https://harness.chance.cc/api/v1/gas/prepare', 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://harness.chance.cc/api/v1/gas/prepare",
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([
'scanId' => '<string>',
'calls' => [
[
'to' => '<string>',
'data' => '<string>',
'value' => '<string>'
]
]
]),
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://harness.chance.cc/api/v1/gas/prepare"
payload := strings.NewReader("{\n \"scanId\": \"<string>\",\n \"calls\": [\n {\n \"to\": \"<string>\",\n \"data\": \"<string>\",\n \"value\": \"<string>\"\n }\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://harness.chance.cc/api/v1/gas/prepare")
.header("x-api-key", "<api-key>")
.header("Content-Type", "application/json")
.body("{\n \"scanId\": \"<string>\",\n \"calls\": [\n {\n \"to\": \"<string>\",\n \"data\": \"<string>\",\n \"value\": \"<string>\"\n }\n ]\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://harness.chance.cc/api/v1/gas/prepare")
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 \"scanId\": \"<string>\",\n \"calls\": [\n {\n \"to\": \"<string>\",\n \"data\": \"<string>\",\n \"value\": \"<string>\"\n }\n ]\n}"
response = http.request(request)
puts response.read_body{
"signatureRequests": [
{
"i": 123,
"type": "<string>",
"rawPayload": "<string>",
"data": "<unknown>"
}
]
}
Gas sponsorship
Prepare a sponsored transaction
Step 1 of gas sponsorship for trader instances on Polygon. Checks the submitted calls against an ALLOW verification and returns the hashes to sign. One sponsorship per verification. Free.
POST
/
api
/
v1
/
gas
/
prepare
Prepare a sponsored transaction
curl --request POST \
--url https://harness.chance.cc/api/v1/gas/prepare \
--header 'Content-Type: application/json' \
--header 'x-api-key: <api-key>' \
--data '
{
"scanId": "<string>",
"calls": [
{
"to": "<string>",
"data": "<string>",
"value": "<string>"
}
]
}
'import requests
url = "https://harness.chance.cc/api/v1/gas/prepare"
payload = {
"scanId": "<string>",
"calls": [
{
"to": "<string>",
"data": "<string>",
"value": "<string>"
}
]
}
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({
scanId: '<string>',
calls: [{to: '<string>', data: '<string>', value: '<string>'}]
})
};
fetch('https://harness.chance.cc/api/v1/gas/prepare', 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://harness.chance.cc/api/v1/gas/prepare",
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([
'scanId' => '<string>',
'calls' => [
[
'to' => '<string>',
'data' => '<string>',
'value' => '<string>'
]
]
]),
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://harness.chance.cc/api/v1/gas/prepare"
payload := strings.NewReader("{\n \"scanId\": \"<string>\",\n \"calls\": [\n {\n \"to\": \"<string>\",\n \"data\": \"<string>\",\n \"value\": \"<string>\"\n }\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://harness.chance.cc/api/v1/gas/prepare")
.header("x-api-key", "<api-key>")
.header("Content-Type", "application/json")
.body("{\n \"scanId\": \"<string>\",\n \"calls\": [\n {\n \"to\": \"<string>\",\n \"data\": \"<string>\",\n \"value\": \"<string>\"\n }\n ]\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://harness.chance.cc/api/v1/gas/prepare")
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 \"scanId\": \"<string>\",\n \"calls\": [\n {\n \"to\": \"<string>\",\n \"data\": \"<string>\",\n \"value\": \"<string>\"\n }\n ]\n}"
response = http.request(request)
puts response.read_body{
"signatureRequests": [
{
"i": 123,
"type": "<string>",
"rawPayload": "<string>",
"data": "<unknown>"
}
]
}
Authorizations
ApiKeyAuthBearerAuth
An API key (chance_sk_live_…) from https://harness.chance.cc/keys.
Body
application/json
Response
Hashes to sign.
Show child attributes
Show child attributes
