Step1: 制作签名

人脸检测API接口签名方法需遵循“AWS API 2.0 签名规范”。

需要将签名字段按照如下方法进行拼接，并按照指定Hash算法计算后，以base64编码方式进行编码。

签名地址字段

签名参数字段

签名内容拼接

将签名地址、签名参数（字典序排序后）以 拼接成string类型的字符串：

例如：

POST\nmosapi.meituan.com/mcs/v1\nAWSAccessKeyId=8b5ad48388a347c185b6b7b0ba9e6225&Action=GetBalance&Format=json&SignatureMethod=HmacSHA256&SignatureVersion=2&Timestamp=2016-11-14T03%3A10%3A55.000Z

生成签名

用SECRET KEY作为秘钥对拼接后的签名内容以HmacSHA256算法进行Hash加密，并进行base64编码，最终获得签名:

例如：

xOnd5MauvUn8Kx8225Nh7tSYnuIB0oi5H2Jb00UU788=

Step2: 接口调用

接口：https://mosapi.meituan.com/mcs/v1

方法：POST

请求参数

返回参数

返回类型：json

返回结果结构如下：

{
  "code": 200,
  "err": "",
  "ret": {
    "face_results": [
      {
        "face_rect": {
          "y": 115,
          "h": 570,
          "w": 570,
          "x": 133
        },
        "gender": "男",
        "angleZ": 1.4695221198907404,
        "angleY": -3.1243755636241892,
        "angleX": -7.797419873311128,
        "landmark_results": {
          "1": {
            "y": 352,
            "x": 317
          },
          "3": {
            "y": 351,
            "x": 364
          },
          "4": {
            "y": 352,
            "x": 466
          },
          "6": {
            "y": 354,
            "x": 514
          },
          "7": {
            "y": 449,
            "x": 365
          },
          "9": {
            "y": 453,
            "x": 448
          },
          "10": {
            "y": 512,
            "x": 347
          },
          "11": {
            "y": 515,
            "x": 459
          },
          "26": {
            "y": 502,
            "x": 402
          },
          "27": {
            "y": 509,
            "x": 402
          },
          "29": {
            "y": 619,
            "x": 396
          },
          "70": {
            "y": 181,
            "x": 421
          },
          "91": {
            "y": 475,
            "x": 258
          },
          "93": {
            "y": 580,
            "x": 303
          },
          "96": {
            "y": 589,
            "x": 508
          },
          "98": {
            "y": 486,
            "x": 568
          }
        }
      }
    ],
    "landmark_image_content": "XX"
  }
}

示例代码

Python示例代码

• 示例代码采用Python3版本
• action字段内容对应Action内容
• access_key、secret_key对应控制台中的Access Key ID、Access Key Secret

#! /usr/bin/env python3
#-*- coding:utf-8 -*-

import base64
import datetime
import hmac
import hashlib
import urllib
import urllib.parse
import requests
import json

access_key = ''  # Access Key ID
secret_key = ''  # Secret Key
image = '' # 图片文件所在地址
landmark_image = False

action = 'PersonFaceFeature'
url = 'https://mosapi.meituan.com/mcs/v1'

def get_utf8_value(value):
    if not isinstance(value, str): #and not isinstance(value, unicodedata):#(python2版本需要此句）
        value = str(value)
    if isinstance(value, str): #unicode):#(python2版本需要此句）
        return value.encode('utf-8')
    else:
        return value

def sign(params):
    pairs = []
    for key in params.keys():
        val = get_utf8_value(params[key])
        val = urllib.parse.quote(val, safe='-_~')
        pairs.append(urllib.parse.quote(key, safe='') + '=' + val)
    query = '&'.join(sorted(pairs))
    msg = ('POST\nmosapi.meituan.com\n/mcs/v1\n%s' % query)
    content = hmac.new(secret_key.encode('utf-8'), msg.encode('utf-8'), hashlib.sha256).digest()
    ret = base64.b64encode(content).decode()
    return ret

def get_image():
    with open(image,'rb') as image1:
        pic = base64.b64encode(image1.read())
    return pic

def pack_data():
    data = {
        'AWSAccessKeyId':access_key,
        'Action': action,
        'Format': 'json',
        'SignatureMethod': 'HmacSHA256',
        'SignatureVersion': '2',
        'Timestamp': datetime.datetime.now().isoformat()[0:-3]+'Z',
        'landmark_image': landmark_image,
    }
    data.update({'Signature' : sign(data)})
    data.update({'image_content' : get_image()})
    return data

def request():
    data = urllib.parse.urlencode(pack_data())
    headers = {
        'Content-type': 'application/x-www-form-urlencoded',
        'Accept': 'text/plain'
    }
    response = requests.post(
        url = url, data = data, headers = headers, verify = True
    )
    resp_format = json.loads(response.content.decode('utf-8'))
    return resp_format

if __name__ == '__main__':
    print(request())

PHP示例代码

$key_id = '您自己的 key_id';
$key_secret = '您自己的 key_secret';
$url = 'https://mosapi.meituan.com/mcs/v1';
$image_location = '您自己的本地图片路径';

function signature($post_array){
    $string_to_sign = "POST\n";
    $string_to_sign .= "mosapi.meituan.com\n";
    $string_to_sign .= "/mcs/v1\n";
    $string_to_sign .= array2xform($post_array);
    global $key_secret;
    $signature = base64_encode(hash_hmac('sha256', $string_to_sign, $key_secret, true));
    return $signature;
}
function array2xform($post_array){
    $string='';
    foreach ($post_array as $k => $v) {
        $string .= "&$k=".rawurlencode($v);
    }
    $string = substr($string, 1);
    return $string;
}
$file = fopen($image_location, 'rb');
$data = fread($file,filesize($image_location));
fclose($file);
$image_content = base64_encode($data);

$ch = curl_init();  
curl_setopt($ch, CURLOPT_URL, $url);
$post_array = array(
    'AWSAccessKeyId' => $key_id,
    'Action' => 'PersonFaceFeature',
    'Format' => 'json',
    'SignatureMethod' => 'HmacSHA256',
    'SignatureVersion' => 2,
    'Timestamp' => date('Y-m-d\TH:i:s.0000\Z', time()),
    'landmark_image' => 'false'
);
$post_array['Signature'] = signature($post_array);
$post_array['image_content'] = $image_content;
$post_string = array2xform($post_array);
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_string);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$out = curl_exec($ch);
curl_close($ch);
echo $out;