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@rafat
Created January 18, 2024 16:56
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Created using remix-ide: Realtime Ethereum Contract Compiler and Runtime. Load this file by pasting this gists URL or ID at https://remix.ethereum.org/#version=soljson-v0.8.19+commit.7dd6d404.js&optimize=false&runs=200&gist=
// SPDX-License-Identifier: MIT
pragma solidity 0.8.19;
// Deploy on Fuji
import {FunctionsClient} from "@chainlink/contracts/src/v0.8/functions/dev/v1_0_0/FunctionsClient.sol";
import {ConfirmedOwner} from "@chainlink/contracts/src/v0.8/shared/access/ConfirmedOwner.sol";
import {FunctionsRequest} from "@chainlink/contracts/src/v0.8/functions/dev/v1_0_0/libraries/FunctionsRequest.sol";
contract TemperatureFunctions is FunctionsClient {
using FunctionsRequest for FunctionsRequest.Request;
// State variables to store the last request ID, response, and error
bytes32 public s_lastRequestId;
bytes public s_lastResponse;
bytes public s_lastError;
// Custom error type
error UnexpectedRequestID(bytes32 requestId);
// Event to log responses
event Response(
bytes32 indexed requestId,
string temperature,
bytes response,
bytes err
);
// Hardcoded for Fuji
// Supported networks https://docs.chain.link/chainlink-functions/supported-networks
address router = 0xA9d587a00A31A52Ed70D6026794a8FC5E2F5dCb0;
bytes32 donID =
0x66756e2d6176616c616e6368652d66756a692d31000000000000000000000000;
//Callback gas limit
uint32 gasLimit = 300000;
// Your subscription ID.
uint64 public s_subscriptionId;
// JavaScript source code
string public source =
"const city = args[0];"
"const apiResponse = await Functions.makeHttpRequest({"
"url: `https://wttr.in/${city}?format=3`,"
"responseType: 'text'"
"});"
"if (apiResponse.error) {"
"throw Error('Request failed');"
"}"
"const { data } = apiResponse;"
"return Functions.encodeString(data);";
string public lastCity;
string public lastTemperature;
constructor(uint64 subscriptionId) FunctionsClient(router) {
s_subscriptionId = subscriptionId;
}
function getTemperature(
string memory _city
) external returns (bytes32 requestId) {
string[] memory args = new string[](1);
args[0] = _city;
FunctionsRequest.Request memory req;
req.initializeRequestForInlineJavaScript(source); // Initialize the request with JS code
if (args.length > 0) req.setArgs(args); // Set the arguments for the request
// Send the request and store the request ID
s_lastRequestId = _sendRequest(
req.encodeCBOR(),
s_subscriptionId,
gasLimit,
donID
);
lastCity = _city;
return s_lastRequestId;
}
/**
* @notice Callback function for fulfilling a request
* @param requestId The ID of the request to fulfill
* @param response The HTTP response data
* @param err Any errors from the Functions request
*/
function fulfillRequest(
bytes32 requestId,
bytes memory response,
bytes memory err
) internal override {
if (s_lastRequestId != requestId) {
revert UnexpectedRequestID(requestId); // Check if request IDs match
}
s_lastError = err;
// Update the contract's state variables with the response and any errors
s_lastResponse = response;
lastTemperature = string(response);
// Emit an event to log the response
emit Response(requestId, lastTemperature, s_lastResponse, s_lastError);
}
}
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