JavaScript code API Reference
JavaScript source code for a Functions request should comply with certain restrictions:
- Allowed Modules: Vanilla Deno and module imports.
- Return Type: Must return a JavaScript
Buffer
object representing the response bytes sent back to the invoking contract. - Time Limit: Scripts must execute within a 10-second timeframe; otherwise, they will be terminated, and an error will be returned to the requesting contract.
HTTP requests
For making HTTP requests, use the Functions.makeHttpRequest
function.
Syntax
const response = await Functions.makeHttpRequest({
url: "http://example.com",
method: "GET", // Optional
// Other optional parameters
})
Parameters
Parameter | Optionality | Description | Default Value |
---|---|---|---|
url | Required | The target URL. | N/A |
method | Optional | HTTP method to be used. | 'GET' |
headers | Optional | HTTP headers for the request. | N/A |
params | Optional | URL query parameters. | N/A |
data | Optional | Body content for the request. | N/A |
timeout | Optional | Maximum request duration in milliseconds. | 3000 ms |
responseType | Optional | Expected response type. | 'json' |
Return Object
Response Type | Fields | Description |
---|---|---|
Success | data | Response data sent by the server. |
status | Numeric HTTP status code. | |
statusText | Textual representation of HTTP status. | |
headers | HTTP headers sent by the server in the response. | |
Error | error | Indicates an error occurred (true ). |
message | Optional error message. | |
code | Optional error code. | |
response | Optional server response. |
Data encoding functions
The Functions library includes several encoding functions, which are useful for preparing data for blockchain contracts.
Function | Input Type | Output Type | Description |
---|---|---|---|
Functions.encodeUint256 | Positive Integer | 32-byte Buffer | Converts a positive integer to a 32-byte Buffer for a uint256 in Solidity. |
Functions.encodeInt256 | Integer | 32-byte Buffer | Converts an integer to a 32-byte Buffer for an int256 in Solidity. |
Functions.encodeString | String | Buffer | Converts a string to a Buffer for a string type in Solidity. |
Note: Using these encoding functions is optional. The source code must return a Uint8Array which represents the bytes
that are returned onchain.
const myArr = new Uint8Array(ARRAY_LENGTH)