<?php
/**
 * Created by PhpStorm.
 * User: FZS
 * Time: 2019/3/13 17:10
 */
//----------------------------------
// 百度应用token调用类
//----------------------------------
class freeApi{
    private $apiKey = false; //百度应用AppID
    private $secretKey = false; //百度应用API Key
    private $tokenUrl = 'https://aip.baidubce.com/oauth/2.0/token';
    public function __construct($apikey,$secretkey){
        $this->apiKey = $apikey;
        $this->secretKey = $secretkey;
    }
    /**
     * 获取token
     * @return array
     */
    public function getToken(){
        $params = [
            'grant_type' => 'client_credentials',
            'client_id'  => $this->apiKey,
            'client_secret' => $this->secretKey,
        ];
        $o = "";
        foreach ( $params as $k => $v )
        {
            $o.= "$k=" . urlencode( $v ). "&" ;
        }
        $params = substr($o,0,-1);
        return $this->returnArray($this->freeApiCurl($this->tokenUrl,$params,1));
    }
    /**
     * 将JSON内容转为数据，并返回
     * @param string $content [内容]
     * @return array
     */
    public function returnArray($content){
        return json_decode($content,true);
    }

    /**
     * 请求接口返回内容
     * @param  string $url [请求的URL地址]
     * @param  string $params [请求的参数]
     * @param  int $ipost [是否采用POST形式]
     * @return  string
     */
    public function freeApiCurl($url,$params=false,$ispost=0){
        $httpInfo = array();
        $ch = curl_init();
        curl_setopt( $ch, CURLOPT_HTTP_VERSION , CURL_HTTP_VERSION_1_1 );
        curl_setopt( $ch, CURLOPT_HTTP_VERSION , CURL_HTTP_VERSION_1_1 );
        curl_setopt( $ch, CURLOPT_USERAGENT , 'free-api' );
        curl_setopt( $ch, CURLOPT_CONNECTTIMEOUT , 60 );
        curl_setopt( $ch, CURLOPT_TIMEOUT , 60);
        curl_setopt( $ch, CURLOPT_RETURNTRANSFER , true );
        if( $ispost )
        {
            curl_setopt( $ch , CURLOPT_POST , true );
            curl_setopt( $ch , CURLOPT_POSTFIELDS , $params );
            curl_setopt( $ch , CURLOPT_URL , $url );
        }
        else
        {
            if($params){
                curl_setopt( $ch , CURLOPT_URL , $url.'?'.$params );
            }else{
                curl_setopt( $ch , CURLOPT_URL , $url);
            }
        }
        $response = curl_exec( $ch );
        if ($response === FALSE) {
            return false;
        }
        $httpCode = curl_getinfo( $ch , CURLINFO_HTTP_CODE );
        $httpInfo = array_merge( $httpInfo , curl_getinfo( $ch ) );
        curl_close( $ch );
        return $response;
    }

}
$api = new freeApi();
var_dump($api->getToken());

package com.baidu.ai.aip.auth;

import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
import java.util.Map;

/**
 * 获取token类
 */
public class AuthService {

    /**
     * 获取权限token
     * @return 返回示例：
     * {
     * "access_token": "24.460da4889caad24cccdb1fea17221975.2592000.1491995545.282335-1234567",
     * "expires_in": 2592000
     * }
     */
    public static String getAuth() {
        // 官网获取的 API Key 更新为你注册的
        String clientId = "百度云应用的AK";
        // 官网获取的 Secret Key 更新为你注册的
        String clientSecret = "百度云应用的SK";
        return getAuth(clientId, clientSecret);
    }

    /**
     * 获取API访问token
     * 该token有一定的有效期，需要自行管理，当失效时需重新获取.
     * @param ak - 百度云官网获取的 API Key
     * @param sk - 百度云官网获取的 Securet Key
     * @return assess_token 示例：
     * "24.460da4889caad24cccdb1fea17221975.2592000.1491995545.282335-1234567"
     */
    public static String getAuth(String ak, String sk) {
        // 获取token地址
        String authHost = "https://aip.baidubce.com/oauth/2.0/token?";
        String getAccessTokenUrl = authHost
                // 1. grant_type为固定参数
                + "grant_type=client_credentials"
                // 2. 官网获取的 API Key
                + "&client_id=" + ak
                // 3. 官网获取的 Secret Key
                + "&client_secret=" + sk;
        try {
            URL realUrl = new URL(getAccessTokenUrl);
            // 打开和URL之间的连接
            HttpURLConnection connection = (HttpURLConnection) realUrl.openConnection();
            connection.setRequestMethod("GET");
            connection.connect();
            // 获取所有响应头字段
            Map<String, List<String>> map = connection.getHeaderFields();
            // 遍历所有的响应头字段
            for (String key : map.keySet()) {
                System.err.println(key + "--->" + map.get(key));
            }
            // 定义 BufferedReader输入流来读取URL的响应
            BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String result = "";
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
            /**
             * 返回结果示例
             */
            System.err.println("result:" + result);
            JSONObject jsonObject = new JSONObject(result);
            String access_token = jsonObject.getString("access_token");
            return access_token;
        } catch (Exception e) {
            System.err.printf("获取token失败！");
            e.printStackTrace(System.err);
        }
        return null;
    }

}

import urllib, urllib2, sys
import ssl

# client_id 为官网获取的AK， client_secret 为官网获取的SK
host = 'https://aip.baidubce.com/oauth/2.0/token?grant_type=client_credentials&client_id=【官网获取的AK】&client_secret=【官网获取的SK】'
request = urllib2.Request(host)
request.add_header('Content-Type', 'application/json; charset=UTF-8')
response = urllib2.urlopen(request)
content = response.read()
if (content):
    print(content)

#include <iostream>
#include <curl/curl.h>
#include <json/json.h>
#include "access_token.h"
// libcurl库下载链接：https://curl.haxx.se/download.html
// jsoncpp库下载链接：https://github.com/open-source-parsers/jsoncpp/
// 获取access_token所需要的url
const std::string access_token_url = "https://aip.baidubce.com/oauth/2.0/token?grant_type=client_credentials";
// 回调函数获取到的access_token存放变量
// static std::string access_token_result;
/**
 * curl发送http请求调用的回调函数，回调函数中对返回的json格式的body进行了解析，解析结果储存在result中
 * @param 参数定义见libcurl库文档
 * @return 返回值定义见libcurl库文档
 */
static size_t callback(void *ptr, size_t size, size_t nmemb, void *stream) {
    // 获取到的body存放在ptr中，先将其转换为string格式
    std::string s((char *) ptr, size * nmemb);
    // 开始获取json中的access token项目
    Json::Reader reader;
    Json::Value root;
    // 使用boost库解析json
    reader.parse(s,root);
    std::string* access_token_result = static_cast<std::string*>(stream);
    *access_token_result = root["access_token"].asString();
    return size * nmemb;
}

/**
 * 用以获取access_token的函数，使用时需要先在百度云控制台申请相应功能的应用，获得对应的API Key和Secret Key
 * @param access_token 获取得到的access token，调用函数时需传入该参数
 * @param AK 应用的API key
 * @param SK 应用的Secret key
 * @return 返回0代表获取access token成功，其他返回值代表获取失败
 */
int get_access_token(std::string &access_token, const std::string &AK, const std::string &SK) {
    CURL *curl;
    CURLcode result_code;
    int error_code = 0;
    curl = curl_easy_init();
    if (curl) {
        std::string url = access_token_url + "&client_id=" + AK + "&client_secret=" + SK;
        curl_easy_setopt(curl, CURLOPT_URL, url.data());
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0);
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0);
        std::string access_token_result;
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &access_token_result);
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, callback);
        result_code = curl_easy_perform(curl);
        if (result_code != CURLE_OK) {
            fprintf(stderr, "curl_easy_perform() failed: %s
",
                    curl_easy_strerror(result_code));
            return 1;
        }
        access_token = access_token_result;
        curl_easy_cleanup(curl);
        error_code = 0;
    } else {
        fprintf(stderr, "curl_easy_init() failed.");
        error_code = 1;
    }
    return error_code;
}

using System;
using System.Collections.Generic;
using System.Net.Http;

namespace com.baidu.ai
{
	public static class AccessToken

	{
	    // 调用getAccessToken()获取的 access_token建议根据expires_in 时间 设置缓存
	    // 返回token示例
		public static String TOKEN = "24.adda70c11b9786206253ddb70affdc46.2592000.1493524354.282335-1234567";

        // 百度云中开通对应服务应用的 API Key 建议开通应用的时候多选服务
		private static String clientId = "百度云应用的AK";
		// 百度云中开通对应服务应用的 Secret Key
		private static String clientSecret = "百度云应用的SK";

		public static String getAccessToken() {
			String authHost = "https://aip.baidubce.com/oauth/2.0/token";
			HttpClient client = new HttpClient();
			List<KeyValuePair<String, String>> paraList = new List<KeyValuePair<string, string>>();
			paraList.Add(new KeyValuePair<string, string>("grant_type", "client_credentials"));
			paraList.Add(new KeyValuePair<string, string>("client_id", clientId));
			paraList.Add(new KeyValuePair<string, string>("client_secret", clientSecret));

			HttpResponseMessage response = client.PostAsync(authHost, new FormUrlEncodedContent(paraList)).Result;
			String result = response.Content.ReadAsStringAsync().Result;
			Console.WriteLine(result);
			return result;
		}
	}
}

var https = require('https');
var qs = require('querystring');

const param = qs.stringify({
    'grant_type': 'client_credentials',
    'client_id': '您的 Api Key',
    'client_secret': '您的 Secret Key'
});

https.get(
    {
        hostname: 'aip.baidubce.com',
        path: '/oauth/2.0/token?' + param,
        agent: false
    },
    function (res) {
        // 在标准输出中查看运行结果
        res.pipe(process.stdout);
    }
);