springboot实现微信小程序二维码生成

痛定思痛。 2022-12-25 11:56 531阅读 0赞

> # 一、微信小程序创建 #

先要去微信公众平台注册一个小程序，每个小程序都有相应的AppID(小程序ID)和AppSecret(小程序密钥)，它们是获取ACCESS\_TOKEN所需要的。微信公众平台地址：

[https://mp.weixin.qq.com/][https_mp.weixin.qq.com]

注册添加小程序后会取得AppID(小程序ID)和AppSecret(小程序密钥)：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA_size_16_color_FFFFFF_t_70][]

> # 二、依赖引入 #

<dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>fastjson</artifactId>
                <version>1.2.41</version>
            </dependency>
            <dependency>
                <groupId>org.apache.httpcomponents</groupId>
                <artifactId>httpclient</artifactId>
            </dependency>
            <dependency>
                <groupId>org.apache.httpcomponents</groupId>
                <artifactId>httpmime</artifactId>
            </dependency>
            <dependency>
                <groupId>com.google.code.gson</groupId>
                <artifactId>gson</artifactId>
            </dependency>

> # 三、核心代码 #

@RequestMapping("/QR")
    @RestController
    public class QRCodeController {
    
        @RequestMapping("/getCode")
        public void createQRCode(String param, String page, HttpServletResponse response) {
            OutputStream stream = null;
            try {
                //获取AccessToken
                String accessToken = getAccessToken();
                //设置响应类型
                response.setContentType("image/png");
                String url = "https://api.weixin.qq.com/wxa/getwxacodeunlimit?access_token=" + accessToken;
                //组装参数
                Map<String, Object> paraMap = new HashMap<>();
                //二维码携带参数 不超过32位 参数类型必须是字符串
                paraMap.put("scene", param);
                //二维码跳转页面
                paraMap.put("page", page);
                //二维码的宽度
                paraMap.put("width", 450);
                //自动配置线条颜色，如果颜色依然是黑色，则说明不建议配置主色调
                paraMap.put("auto_color", false);
                //是否需要透明底色， is_hyaline 为true时，生成透明底色的小程序码
                paraMap.put("is_hyaline", false);
                //执行post 获取数据流
                byte[] result = HttpClientUtils.doImgPost(url, paraMap);
                //输出图片到页面
                response.setContentType("image/jpg");
                stream = response.getOutputStream();
                stream.write(result);
                stream.flush();
                stream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 获取ACCESS_TOKEN
         * 官方文档地址:https://developers.weixin.qq.com/miniprogram/dev/api-backend/open-api/access-token/auth.getAccessToken.html
         * <p>
         * 需要正确的 appid  和 secret  查看自己的微信开放平台
         */
        public String getAccessToken() {
            //这里需要换成你d的小程序appid
            String appid = "wx141ac029d803ce4c";
            //这里需要换成你的小程序secret
            String appSecret = "bb245ef5f0add972bccd718087b7dd50";
            //获取微信ACCESS_TOKEN 的Url
            String accent_token_url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=APPID&secret=APPSECRET";
            String url = accent_token_url.replace("APPID", appid).replace("APPSECRET", appSecret);
            //发送请求
            String result = HttpClientUtils.doGet(url);
            Map<String, Object> resultMap = (Map<String, Object>) JsonUtil.jsonToMap(result);
            System.out.println("access_token------>" + resultMap.get("access_token").toString());
            return resultMap.get("access_token").toString();
        }
    
    }

public class HttpClientUtils {
        private static final Logger LOGGER = LoggerFactory.getLogger(HttpClientUtils.class);
    
        private static ConnectionSocketFactory plainsf = null;
        private static LayeredConnectionSocketFactory sslsf = null;
        private static Registry<ConnectionSocketFactory> registry = null;
        private static PoolingHttpClientConnectionManager cm = null;
    
        private static HttpRequestRetryHandler httpRequestRetryHandler = null;
    
        private static RequestConfig requestConfig = null;
    
        private static CloseableHttpClient httpClient = null;
    
        static {
            plainsf = PlainConnectionSocketFactory.getSocketFactory();
            sslsf = SSLConnectionSocketFactory.getSocketFactory();
            registry = RegistryBuilder.<ConnectionSocketFactory>create()
                    .register("http", plainsf)
                    .register("https", sslsf)
                    .build();
            cm = new PoolingHttpClientConnectionManager(registry);
            // 最大连接数
            cm.setMaxTotal(30);
            // 每个路由基础的连接
            cm.setDefaultMaxPerRoute(10);
            //请求重试处理
            httpRequestRetryHandler = new HttpRequestRetryHandler() {
                @Override
                public boolean retryRequest(IOException exception, int executionCount, HttpContext context) {
                    if (executionCount >= 5) {// 如果已经重试了5次，就放弃
                        return false;
                    }
                    if (exception instanceof NoHttpResponseException) {// 如果服务器丢掉了连接，那么就重试
                        return true;
                    }
                    if (exception instanceof SSLHandshakeException) {// 不要重试SSL握手异常
                        return false;
                    }
                    if (exception instanceof InterruptedIOException) {// 超时
                        return false;
                    }
                    if (exception instanceof UnknownHostException) {// 目标服务器不可达
                        return false;
                    }
                    if (exception instanceof ConnectTimeoutException) {// 连接被拒绝
                        return false;
                    }
                    if (exception instanceof SSLException) {// ssl握手异常
                        return false;
                    }
    
                    HttpClientContext clientContext = HttpClientContext.adapt(context);
                    HttpRequest request = clientContext.getRequest();
                    // 如果请求是幂等的，就再次尝试
                    if (!(request instanceof HttpEntityEnclosingRequest)) {
                        return true;
                    }
                    return false;
                }
            };
    
            requestConfig = RequestConfig.custom()
                    .setConnectionRequestTimeout(5000)
                    .setConnectTimeout(5000)
                    .setSocketTimeout(5000)
                    .build();
    
            httpClient = HttpClients.custom()
                    .setConnectionManager(cm)
                    .setRetryHandler(httpRequestRetryHandler)
                    .build();
    
        }
    
        /**
         * get请求
         *
         * @param url       访问ur
         * @return
         */
        public static String doGet(String url) {
            String result = null;
            CloseableHttpResponse response = null;
            HttpGet httpget = new HttpGet(url);
            try {
                String resultEnc = "UTF-8";
                httpget.setConfig(requestConfig);
                response = httpClient.execute(httpget, HttpClientContext.create());
                result = EntityUtils.toString(response.getEntity(), resultEnc);
            } catch (Exception e) {
                LOGGER.error("get请求 doPost", e);
                return result;
            } finally {
                if (null != response) {
                    try {
                        response.close();
                    } catch (IOException e) {
                        LOGGER.error("get请求 doPost  IOException", e);
                    }
                }
                httpget.abort();
            }
            return result;
        }
    
        /**
         * 获取数据流
         *
         * @param url
         * @param paraMap
         * @return
         */
        public static byte[] doImgPost(String url, Map<String, Object> paraMap) {
            byte[] result = null;
            HttpPost httpPost = new HttpPost(url);
            httpPost.addHeader("Content-Type", "application/json");
            try {
                // 设置请求的参数
                JSONObject postData = new JSONObject();
                for (Map.Entry<String, Object> entry : paraMap.entrySet()) {
                    postData.put(entry.getKey(), entry.getValue());
                }
                httpPost.setEntity(new StringEntity(postData.toString(), "UTF-8"));
                HttpClient httpClient = HttpClientBuilder.create().build();
                HttpResponse response = httpClient.execute(httpPost);
                HttpEntity entity = response.getEntity();
                result = EntityUtils.toByteArray(entity);
            } catch (ConnectionPoolTimeoutException e) {
                e.printStackTrace();
            } catch (ConnectTimeoutException e) {
                e.printStackTrace();
            } catch (SocketTimeoutException e) {
                e.printStackTrace();
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                httpPost.releaseConnection();
            }
            return result;
        }
    }

public class JsonUtil {
    
    	private static Gson gson = new Gson();
    
    	public static Map<?, ?> jsonToMap(String jsonStr) {
    		Map<?, ?> objMap = null;
    		if (gson != null) {
    			Type type = new com.google.gson.reflect.TypeToken<Map<?, ?>>() {
    			}.getType();
    			objMap = gson.fromJson(jsonStr, type);
    		}
    		return objMap;
    	}
    }

> # 四、效果展示 #

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA_size_16_color_FFFFFF_t_70 1][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA_size_16_color_FFFFFF_t_70 2][]

[https_mp.weixin.qq.com]: https://mp.weixin.qq.com/
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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20201201223449402.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA==,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA_size_16_color_FFFFFF_t_70 2]: https://img-blog.csdnimg.cn/20201201223623356.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA==,size_16,color_FFFFFF,t_70