I. wechat interface documents

• Navigation: wechat official documentation –> Server –> interface call credentials –> getAccessToken
• Specific call please go to the official document to view

Access_token storage and update

It’s in the interface documentation. Please read the interface documentation carefully

• access_tokenStorage should be retained at least512Character space;
• access_tokenIs currently valid for2 hours, need to periodically refresh, repeated acquisition will result in the last acquisitionaccess_tokenFailure;
• It is recommended that developers use the central control server for unified access and refreshaccess_token, used by other business logic serversaccess_tokenAll are from the central control server, should not be refreshed separately, otherwise it is easy to cause conflicts, resulting inaccess_tokenCoverage affects business;
• access_tokenThe validity period is returned byexpires_inTo convey, for now7200 secondsThe central control server needs to refresh in advance according to this effective time. In the refresh process, the central control server can continue to output the oldaccess_tokenAt this time, the public platform background will be guaranteed in5 minutesThe new and oldaccess_tokenAre available, which ensures a smooth transition of third-party services;
• access_tokenThe effective time may be adjusted in the future, so the central control server not only needs internal timing active refresh, but also needs to provide passive refreshaccess_tokenTo make it easy for the business server to learn from the API callaccess_tokenCan be triggered if the timeout has expiredaccess_tokenRefresh process.

For details, please refer to the document “Obtaining Access_Token” of wechat Public Platform.

PHP generates access_token for wechat applets

1, code,

public function test() {
    $accessToken = self::getAccessToken();
    echo "access_token is {$accessToken}";
}

public function getAccessToken() {
    $url = 'https://api.weixin.qq.com/cgi-bin/token';
    $data = [
        'grant_type'= >'client_credential'./ / fill in client_credential
        'appid'= >'wx523***********'.// Applet unique credentials: AppID 16-bit hexadecimal (lowercase)
        'secret'= >'c4ca4238a0************9a6f75849b' // Applets unique credentials: AppSecret 32-bit hexadecimal (lowercase) => similar to MD5 ()
    ];
    $apiUrl = self::getUrl($url.$data);
    $result =  json_decode(self::curlGet($apiUrl),true);
    $accessToken = isset($result['access_token'])?$result['access_token'] : ' ';
    if (!$accessToken) {
        die(json_encode($result, JSON_UNESCAPED_UNICODE)); // Output error
    }
    return $accessToken;
}

/ / url generator
public function getUrl($apiUrl.$param = []){
    $param = http_build_query($param);
    return $apiUrl . '? ' . $param;
}

public function curlGet($url.$header = []) {
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_HTTPGET, true);
    if ($header) {
        curl_setopt($ch, CURLOPT_HTTPHEADER, $header);
    }
    curl_setopt($ch, CURLOPT_TIMEOUT, 30); // Set the timeout period to 30s
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE); // Ignore SSL detection
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); //1 or TRUE returns information retrieved by curl_exec() as a string rather than output it directly. -
    curl_setopt($ch, CURLINFO_HEADER_OUT, true); // trace the request string for the handle when TRUE, available as of PHP 5.1.3. And this is key, is to allow you to see the request header
    $output = curl_exec($ch);
    if (!$output) {
// echo "request $url fail:", (array)curl_error($ch); // Log
    }
    curl_close($ch);
// echo "request $url success:" . json_encode(array($url, $header, $output), true); // Log
    return $output;
}
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2, print,

• Due to theappid.secretNot true and valid, so print it below

{"errcode":40013,"errmsg":"invalid appid rid: 609deb67-3288bef4-69fe5dee"}
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• Return to normal

{"access_token":"ACCESS_TOKEN","expires_in":7200}
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