support voice prompt translation in 4 languages

README.md

@@ -94,13 +94,37 @@ The tests cover the following cases:
 
 
 ###### API Specification:
-Request Type | API Endpoint | Parameters | Returns | Purpose
------------- | ------------- | ------------- | ------------- | -------------
-HTTP GET | / or /status | | OK | Returns "OK" if the service is running
-HTTP POST | /captcha | request body: { nonce: string } | {  "nonce": string,  "captcha": string,  validation": JSON}| Retrieve a captcha to be displayed to a user
-HTTP POST | /captcha/audio | request body: { validation: JSON } | {  "audio": dataUri}| Retrieve the audio for a given captcha validation object, returns MP3 in DataUri format
-HTTP POST | /verify/captcha | request body: { nonce: string, answer: string, validation: JSON } | { valid: true/false, jwt: JWT } | Compare the answer to the encryptedAnswer, return a signed JWT if successful
-HTTP POST | /verify/jwt | request body: { nonce: string, token: JWT } | { valid: true/false } | Validate a signed JWT by resource server
+
+* GET / or /status 
+    * returns: "OK" if the service is running
+* POST /captcha
+    * input: request body: { nonce: \<string\> }
+    * returns: {nonce: \<string\>,  captcha: \<string\>,  validation: \<JSON\>}
+
+    Retrieve a captcha to be displayed to a user
+* POST /captcha/audio
+    * input: request body: { validation: \<JSON\> [, translation: \<string\>\|true] }
+    * returns: {audio: \<dataUri\>}
+
+    Retrieve the audio for a given captcha validation object, returns MP3 in DataUri format. The audio prompt is spoken in English unless *transaltion* is specified. *transaltion* can be either a string of one of following supported language acronyms    
+
+    * *en* (English)
+    * *fr* (French)
+    * *pa* (Punjabi)
+    * *zh* (Mandarin Chinese)
+
+    or the boolean value of *true*. If *transaltion* is set to *true*, then the first language set in the http *Accept-Language* request header matching the above list is chosen. If there is no match, then fall backs to English.
+
+* POST /verify/captcha
+    * input: request body: { nonce: \<string\>, answer: \<string\>, validation: \<JSON\> }
+    * returns: { valid: true\|false, jwt: \<JWT\> }
+
+    Compare the answer to the encryptedAnswer, return a signed JWT if the answer if valid
+* POST /verify/jwt
+    * input: request body: { nonce: \<string\>, token: \<JWT\> }
+    * returns: { valid: true\|false } 
+
+    Validate a signed JWT by resource server
 
 #### API Demo
 You can try it out the API for yourself at our demo environment by following the above API specs:

app.code-workspace

@@ -5,6 +5,9 @@
 		},
 		{
 			"path": "../text2wav.node.js"
+		},
+		{
+			"path": "../MyGovBC-CAPTCHA-Widget"
 		}
 	],
 	"settings": {}

package.json

@@ -1,6 +1,6 @@
 {
   "name": "mygovbc-captcha-service",
-  "version": "7.1.0",
+  "version": "7.2.0",
   "description": "A reusable, secure and reliable CAPTCHA microservice for service providers to use within online digital services.",
   "main": "lib/index.js",
   "scripts": {
@@ -24,7 +24,7 @@
     "os": "^0.1.1",
     "streamifier": "^0.1.1",
     "svg-captcha": "^1.3.1",
-    "text2wav": "^0.0.7",
+    "text2wav": "^0.0.10",
     "ts-node": "^7.0.1",
     "typescript": "^3.1.3",
     "wav": "^1.0.1",

src/index.ts

@@ -340,9 +340,17 @@ app.post('/verify/captcha', async function (req: Request, res: Response) {
 ////////////////////////////////////////////////////////
 interface GetAudioRequestBody {
   validation: object,
+  translation?: string | boolean,
 }
 
-var getAudio = async function (body: GetAudioRequestBody) {
+const voicePromptLanguageMap: { [index: string]: string } = {
+  en: 'Please type in following letters or numbers', // english
+  fr: 'Veuillez saisir les lettres ou les chiffres suivants', // french
+  pa: 'ਕਿਰਪਾ ਕਰਕੇ ਹੇਠ ਲਿਖੇ ਅੱਖਰ ਜਾਂ ਨੰਬਰ ਟਾਈਪ ਕਰੋ', // punjabi
+  zh: '请输入以下英文字母或数字', // mandarin chinese
+}
+
+var getAudio = async function (body: GetAudioRequestBody, req?: Request) {
   winston.debug(`getting audio for`, body)
   try {
     // Ensure audio is enabled.
@@ -362,11 +370,25 @@ var getAudio = async function (body: GetAudioRequestBody) {
 
     // Insert leading text and commas to slow down reader
     var captchaCharArray = decryptedBody.answer.toString().split("")
-    var spokenCatpcha = "Please type in following letters or numbers: "
+    let language = 'en'
+    if (body.translation) {
+      if (typeof body.translation == 'string') {
+        if (voicePromptLanguageMap.hasOwnProperty(<string>body.translation)) {
+          language = <string>body.translation
+        }
+      }
+      else if (body.translation === true && req && req.headers['accept-language']) {
+        let lang = (<string>req.headers['accept-language']).split(',').map(e => e.split(';')[0].split('-')[0]).find(e => voicePromptLanguageMap.hasOwnProperty(e))
+        if (lang) {
+          language = lang
+        }
+      }
+    }
+    var spokenCatpcha = voicePromptLanguageMap[language] + ": "
     for (var i = 0; i < captchaCharArray.length; i++) {
       spokenCatpcha += captchaCharArray[i] + ", "
     }
-    let audioDataUri = await getMp3DataUriFromText(spokenCatpcha)
+    let audioDataUri = await getMp3DataUriFromText(spokenCatpcha, language)
     // Now pass back the full payload ,
     return {
       audio: audioDataUri
@@ -380,7 +402,7 @@ var getAudio = async function (body: GetAudioRequestBody) {
 }
 
 app.post('/captcha/audio', async function (req: Request, res: Response) {
-  let ret = await getAudio(req.body)
+  let ret = await getAudio(req.body, req)
   return res.send(ret)
 })
 
@@ -440,7 +462,7 @@ app.post('/verify/jwt', async function (req: Request, res: Response) {
  * Audio routines
  */
 ////////////////////////////////////////////////////////
-function getMp3DataUriFromText(text: string) {
+function getMp3DataUriFromText(text: string, language: string = 'en') {
   winston.debug("Starting audio generation...")
   return new Promise(async function (resolve) {
 
@@ -480,7 +502,7 @@ function getMp3DataUriFromText(text: string) {
 
     // Generate audio, Base64 encoded WAV in DataUri format including mime type header
     winston.debug("Generate speach as WAV in ArrayBuffer")
-    var audioArrayBuffer = await text2wav(text)
+    let audioArrayBuffer = await text2wav(text, { voice: language })
 
     // convert to buffer
     winston.debug("Convert arraybuffer to buffer")