Add QR encoder to an API. Add rendering of shares as QR codes to front-end.

pom.xml

@@ -48,7 +48,12 @@
             <groupId>rs.in.zivanovic</groupId>
             <artifactId>sss</artifactId>
             <version>1.0.0</version>
-        </dependency>    
+        </dependency>
+        <dependency>
+            <groupId>net.glxn.qrgen</groupId>
+            <artifactId>javase</artifactId>
+            <version>2.0</version>
+        </dependency>
     </dependencies>
 
     <build>

src/main/java/rs/in/zivanovic/share/a/secret/api/controllers/AbstractSasController.java

@@ -0,0 +1,44 @@
+/*
+ * The MIT License
+ *
+ * Copyright 2014 Marko Zivanovic.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package rs.in.zivanovic.share.a.secret.api.controllers;
+
+import org.springframework.validation.BindingResult;
+import rs.in.zivanovic.share.a.secret.api.dto.SasResponse;
+
+/**
+ * Base class for our controllers. It contains common methods used across different controllers.
+ *
+ * @author Marko Zivanovic <marko@zivanovic.in.rs>
+ */
+public abstract class AbstractSasController {
+
+    protected SasResponse processValidationErrors(BindingResult br) {
+        SasResponse r = SasResponse.badRequest();
+        br.getFieldErrors().stream().forEach(err -> {
+            r.withInvalidParameterValueError(err.getField(), err.getRejectedValue(), err.getDefaultMessage());
+        });
+        return r;
+    }
+
+}

src/main/java/rs/in/zivanovic/share/a/secret/api/controllers/QrCodecController.java

@@ -0,0 +1,73 @@
+/*
+ * The MIT License
+ *
+ * Copyright 2014 Marko Zivanovic.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package rs.in.zivanovic.share.a.secret.api.controllers;
+
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+import java.io.ByteArrayOutputStream;
+import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
+import java.util.List;
+import net.glxn.qrgen.core.image.ImageType;
+import net.glxn.qrgen.javase.QRCode;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+import rs.in.zivanovic.share.a.secret.api.dto.SasResponse;
+
+/**
+ *
+ * @author Marko Zivanovic <marko@zivanovic.in.rs>
+ */
+@RestController
+@RequestMapping("/qr")
+public class QrCodecController extends AbstractSasController {
+
+    private static final List<Integer> VALID_SIZES = Arrays.asList(50, 100, 200, 250);
+
+    @RequestMapping(method = RequestMethod.GET, value = "/encode")
+    public ResponseEntity encode(
+            @RequestParam(value = "text", required = true) String text,
+            @RequestParam(value = "size", required = false, defaultValue = "250") int size,
+            @RequestParam(value = "ecl", required = false, defaultValue = "H") ErrorCorrectionLevel ecl) {
+        ResponseEntity response;
+        if (!VALID_SIZES.contains(size)) {
+            response = SasResponse.badRequest().
+                    withError(SasResponse.Error.INVALID_PARAMETER_VALUE,
+                            "Invalid QR code size, supported sizes: " + VALID_SIZES.toString()).build();
+        } else {
+            ByteArrayOutputStream baos = QRCode.from(text).to(ImageType.JPG).
+                    withSize(size, size).withCharset(StandardCharsets.US_ASCII.name()).
+                    withErrorCorrection(ecl).stream();
+            HttpHeaders headers = new HttpHeaders();
+            headers.add("Content-Type", "image/jpeg");
+            response = new ResponseEntity<>(baos.toByteArray(), headers, HttpStatus.OK);
+        }
+        return response;
+    }
+
+}

src/main/java/rs/in/zivanovic/share/a/secret/api/controllers/SasController.java

@@ -50,7 +50,7 @@ import rs.in.zivanovic.sss.ShamirSecretSharing;
  */
 @RestController
 @RequestMapping("/sas")
-public class SasController {
+public class SasController extends AbstractSasController {
 
     @Value("${info.build.version:'<N/A>'}")
     private String version;
@@ -94,14 +94,6 @@ public class SasController {
         return SasResponse.ok().withData(new VersionResponse(version, buildTime)).build();
     }
 
-    private SasResponse processValidationErrors(BindingResult br) {
-        SasResponse r = SasResponse.badRequest();
-        br.getFieldErrors().stream().forEach(err -> {
-            r.withInvalidParameterValueError(err.getField(), err.getRejectedValue(), err.getDefaultMessage());
-        });
-        return r;
-    }
-
     private List<SecretShare> decodeSecretShares(JoinParameters params) {
         List<SecretShare> shares = new ArrayList<>(params.getShares().size());
         params.getShares().stream().forEach(share -> {

src/main/java/rs/in/zivanovic/share/a/secret/api/dto/SplitResponse.java

@@ -24,8 +24,8 @@
 package rs.in.zivanovic.share.a.secret.api.dto;
 
 import java.util.ArrayList;
+import java.util.Base64;
 import java.util.List;
-import org.apache.tomcat.util.codec.binary.Base64;
 import rs.in.zivanovic.sss.SasUtils;
 import rs.in.zivanovic.sss.SecretShare;
 
@@ -40,7 +40,7 @@ public class SplitResponse {
     public SplitResponse(List<SecretShare> shares) {
         this.shares.clear();
         shares.stream().forEachOrdered(share -> {
-            this.shares.add(Base64.encodeBase64String(SasUtils.encodeToBinary(share)));
+            this.shares.add(Base64.getUrlEncoder().encodeToString(SasUtils.encodeToBinary(share)));
         });
     }
 

src/main/resources/static/js/services.js

@@ -22,21 +22,22 @@
  * THE SOFTWARE.
  */
 
-var API_BASE = "https://share-a-secret-api.herokuapp.com/sas";
+//var API_BASE = "https://share-a-secret-api.herokuapp.com";
+var API_BASE = "http://localhost:8080";
 
 angular.module('sasServices', []).
         factory('SasService', ['$resource', function ($resource) {
                 return $resource(API_BASE, {}, {
                     split: {
-                        url: API_BASE + "/split",
+                        url: API_BASE + "/sas/split",
                         method: "POST"
                     },
                     join: {
-                        url: API_BASE + "/join",
+                        url: API_BASE + "/sas/join",
                         method: "POST"
                     },
                     version: {
-                        url: API_BASE + "/version",
+                        url: API_BASE + "/sas/version",
                         method: "GET"
                     }
                 });

src/main/resources/static/split.html

@@ -32,10 +32,10 @@
     </div>
 
     <div class="row" ng-show="shares.length">
-        <div class="row">
-            <hr/>
-            <h1>Here are your secret shares ...</h1>
-        </div>
+        <!--<hr/>-->
+        <h1>Here are your secret shares ...</h1>
+        <!--        <div class="row">
+                </div>-->
 
         <tabset>
             <tab>
@@ -59,6 +59,19 @@
                     </div>
                 </div>
             </tab>
+            <tab>
+                <tab-heading><i class="glyphicon glyphicon-qrcode"></i> QR codes</tab-heading>
+                <div class="panel panel-default">
+                    <div class="panel-body">
+                        <p class="text-muted">Use QR encoded shares for easy scanning into mobile devices.</p>
+                        <div class="row">
+                            <div ng-repeat="share in shares">
+                                <div class="col-md-2"><img ng-src="/qr/encode?text={{share}}&size=200&ecl=M"/></div>
+                            </div>
+                        </div>
+                    </div>
+                </div>
+            </tab>
         </tabset>
     </div>
 </div>