Php 如何仅使用Google Drive'；检查访问令牌是否有效；什么是RESTAPI？

我正在用PHP实现对的答案，其中已经有转换的代码

但是，当我运行该代码时，我会收到：

HTTP/1.1 400 Bad Request
Vary: X-Origin
Content-Type: application/json; charset=UTF-8
Date: Wed, 06 Sep 2017 22:29:24 GMT
Expires: Wed, 06 Sep 2017 22:29:24 GMT
Cache-Control: private, max-age=0
X-Content-Type-Options: nosniff
X-Frame-Options: SAMEORIGIN
X-XSS-Protection: 1; mode=block
Server: GSE
Alt-Svc: quic=":443"; ma=2592000; v="39,38,37,35"
Accept-Ranges: none
Vary: Origin,Accept-Encoding
Transfer-Encoding: chunked

{
 "error": "unsupported_grant_type",
 "error_description": "Invalid grant_type: "
}

---

我的帖子字段的格式与JavaScript答案中的格式完全相同，甚至URL编码的格式与PHP中的格式完全相同。我在中打开了相同的刷新令牌，在尝试刷新访问令牌时收到了相同的消息。

两周前完成了此操作，但忘记发布我自己的答案。以下是我创建的用于获取令牌和下载文件的方法：

const CLIENT_ID = "";
const CLIENT_SECRET = "";

private $refresh_token;
private $access_token;
private $file_id;
private $output_path;
private $token_filename;

public function is_token_valid() {
    $startTime = new \DateTime();

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Checking if access token ' . trim($this->access_token) . ' is valid...');

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, "https://www.googleapis.com/oauth2/v3/tokeninfo?access_token="  . urlencode($this->access_token));
    curl_setopt($ch, CURLOPT_PORT, 443);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    $response = curl_exec($ch);

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Checking token information...');
    if ($response === false) {
        error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Error while checking access token...');
        throw new \Exception("Token check triggered cURL error " + curl_errno($ch) . ": " . curl_error($ch));
    }

    $response = json_decode($response, true);

    return !(isset($response['error']) || isset($response['error_description']));
}

public function get_access_token() {
    $startTime = new \DateTime();
    $post_fields = "grant_type=refresh_token&client_id=" . urlencode(self::CLIENT_ID) . "&client_secret=" . urlencode(self::CLIENT_SECRET) . "&refresh_token=" . urlencode($this->refresh_token);

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Getting access token for refresh token ' . urlencode($this->refresh_token) . ' ...');
    //error_log($post_fields);

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, "https://www.googleapis.com/oauth2/v4/token");
    curl_setopt($ch, CURLOPT_PORT , 443);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_POST, 1);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $post_fields);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HEADER, false);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array("Content-Type: application/x-www-form-urlencoded"));
    $response = curl_exec($ch);
    $response = json_decode($response, true);

    if ($response === false) {
        throw new \Exception("Fetching access token triggered cURL error " + curl_errno($ch) . ": " . curl_error($ch));
    }

    if (!isset($response['access_token'])) {
        throw new \Exception("Error fetching access token: " . json_encode($response));
    }
    $this->access_token = $response['access_token'];
    file_put_contents($this->token_filename, $this->access_token);

    return $this->access_token;
}

public function download_file() {
    $startTime = new \DateTime();
    $url = "https://www.googleapis.com/drive/v3/files/{$this->file_id}/export?mimeType=text/csv";

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Downloading CSV with URL ' . $url . ' ...');

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_PORT , 443);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HEADER, false);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array("Authorization: Bearer " . $this->access_token));
    $response = curl_exec($ch);

    if (curl_getinfo($ch, CURLINFO_HTTP_CODE) != 200) {
        $response = json_decode($response);
        throw new \Exception("CSV download was not successful: " + json_encode($response));
    }

    $tmp = tmpfile();
    $path = stream_get_meta_data($tmp)['uri'];
    file_put_contents($path, $response);

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Saved URL to ' . $path . ' ...');

    return $path;
}

// ...

if (!$this->is_token_valid()) {
    $this->get_access_token();
}
$this->download_file();

---

为什么不试试这个？它有一个用于在到期时刷新令牌的示例。@noogui这必须自动执行，据我所知，PHP库需要同意。请先尝试一下。@noogui我应该更具体一些。在我们的系统中，我们目前正在使用google api php客户端在用户同意的情况下在前端从google下载CSV，但对于新客户端，我们需要每小时自动下载CSV。我可以获得一个新的访问令牌，但我不知道如何在运行API调用之前验证我当前的访问令牌是否有效。

const CLIENT_ID = "";
const CLIENT_SECRET = "";

private $refresh_token;
private $access_token;
private $file_id;
private $output_path;
private $token_filename;

public function is_token_valid() {
    $startTime = new \DateTime();

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Checking if access token ' . trim($this->access_token) . ' is valid...');

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, "https://www.googleapis.com/oauth2/v3/tokeninfo?access_token="  . urlencode($this->access_token));
    curl_setopt($ch, CURLOPT_PORT, 443);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    $response = curl_exec($ch);

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Checking token information...');
    if ($response === false) {
        error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Error while checking access token...');
        throw new \Exception("Token check triggered cURL error " + curl_errno($ch) . ": " . curl_error($ch));
    }

    $response = json_decode($response, true);

    return !(isset($response['error']) || isset($response['error_description']));
}

public function get_access_token() {
    $startTime = new \DateTime();
    $post_fields = "grant_type=refresh_token&client_id=" . urlencode(self::CLIENT_ID) . "&client_secret=" . urlencode(self::CLIENT_SECRET) . "&refresh_token=" . urlencode($this->refresh_token);

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Getting access token for refresh token ' . urlencode($this->refresh_token) . ' ...');
    //error_log($post_fields);

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, "https://www.googleapis.com/oauth2/v4/token");
    curl_setopt($ch, CURLOPT_PORT , 443);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_POST, 1);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $post_fields);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HEADER, false);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array("Content-Type: application/x-www-form-urlencoded"));
    $response = curl_exec($ch);
    $response = json_decode($response, true);

    if ($response === false) {
        throw new \Exception("Fetching access token triggered cURL error " + curl_errno($ch) . ": " . curl_error($ch));
    }

    if (!isset($response['access_token'])) {
        throw new \Exception("Error fetching access token: " . json_encode($response));
    }
    $this->access_token = $response['access_token'];
    file_put_contents($this->token_filename, $this->access_token);

    return $this->access_token;
}

public function download_file() {
    $startTime = new \DateTime();
    $url = "https://www.googleapis.com/drive/v3/files/{$this->file_id}/export?mimeType=text/csv";

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Downloading CSV with URL ' . $url . ' ...');

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_PORT , 443);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HEADER, false);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array("Authorization: Bearer " . $this->access_token));
    $response = curl_exec($ch);

    if (curl_getinfo($ch, CURLINFO_HTTP_CODE) != 200) {
        $response = json_decode($response);
        throw new \Exception("CSV download was not successful: " + json_encode($response));
    }

    $tmp = tmpfile();
    $path = stream_get_meta_data($tmp)['uri'];
    file_put_contents($path, $response);

    error_log('[' . $startTime->format('Y-m-d h:i:s') . '] Saved URL to ' . $path . ' ...');

    return $path;
}

// ...

if (!$this->is_token_valid()) {
    $this->get_access_token();
}
$this->download_file();