NodeJs is used to translate JS/TS files

As for realizing the function of translation (taking Chinese-English translation as an example), we can divide it into several steps:

Read the file
Find out the Chinese in the text
Put the Chinese phrases or sentences in the text into an array
Invoke a common translation interface for asynchronous translation
The translated English will be backfilled in the meeting documents

First, build the environment

Open the terminal and type: node -v

-bash: node: Command not found

The Node environment is not set up. Please go to the official website to download.

If a version number like v10.16.0 appears on the terminal, your Node environment is set up.

Second, read the file

We first read the fixed file, and then we will try to translate the uploaded file. If you need it, you can move to the later content.

First we create a replace.js file in our folder to write our code.

Then create a js/ts file for us to translate, such as: desutils.ts, the code is as follows:

const desKeyObj = {
  desKey: 'ztesoftbasemobile20160812.. '.ivKey: '01234567890'
}
export default {
  /** * encryption * @param dataStr */
  encrypt: function (dataStr) {
    try {
        console.log("If this is a paragraph. And there's punctuation.");
    } catch (error) {
        console.log('Encryption error' + JSON.stringify(error)); }},/** ** @param dataStr decrypt */
  crypto: function (dataStr) {
    try {
        console.log(' ');
    } catch (error) {
        console.log('Decryption error')}}}Copy the code

Now we start writing the replace.js file to read the desutil.ts file.

First we can use the require command to import the modules we need.

var fs = require('fs');
Copy the code

Node reads and writes files based on a Stream.

There are four flow types under the FS module:

Readable – Readable operation
Writable – Writable operation
Duplex – Readable and write operation
Transform – The operation is written to the data and then read out the result

There are also four types of operations for streams:

Data – Triggered when there is data to read
End – Triggered when there is no more data to read
Error – Triggered when an error occurs during receive and write
Finish – Triggered when all data has been written to the underlying system

Don’t worry, you can understand it through the following code.

Create a readable stream and handle stream events:

// Create a readable stream
let readerStream = fs.createReadStream('DesUtils.ts');
readerStream.setEncoding('UTF8');

let data = ' ';

/ / processing flow
readerStream.on('data', (chunk) => {
   data += chunk;
});

readerStream.on('end', () = > {console.log(data);
});

/ / don't write
readerStream.on('error', (err) => {
   console.log(err.stack);
});
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We have written the code to read the file, now let’s try it:

The terminal goes to the folder, types: node replace.js, and, unsurprisingly, the contents of the file are displayed on the terminal.

List all contents in Chinese

Data processing on the data, we will take out the Chinese text through regular expression. Modify the above code:

readerStream.on('data', (chunk) => {
  const reg = /[\u4e00-\u9fa5]/g;
  while(list = reg.exec(chunk)) {
    console.log(list[0]); }})Copy the code

Ok, now we have taken out all the Chinese, if we need to delete the Chinese, we just need to delete these Chinese.

If it is translated into English, it can not be translated word by word, right?

Therefore, we need to classify the Chinese, which should be phrases into phrases, and which should be sentences into sentences, with an array to store.

My approach is to judge by the index of each word. Is it adjacent to the previous Chinese index? If it is, it should not be separated and stored as a word or sentence. (You may not understand it, you can directly analyze the code ~)

If there is a better method, you can try it yourself

readerStream.on('data', (chunk) => {

  var reg = /[\u4e00-\u9fa5]/g;
  let index = 0;
  let termList = [];    // Iterate over the Chinese array
  let term = ' ';
  data = chunk;

  while (list = reg.exec(chunk)) {
    if((list.index ! == index +1) && term) {
      termList.push(term);
      term = ' ';
    }
    term += list[0];
    index = list.index;
  }
  termList.push(term);
  console.log(termList);    // Print Chinese data
})
Copy the code

Using the code above, we’ve already distinguished phrases, sentences, and so on. The terminal will see the data [‘ encrypt ‘, ‘if this is a paragraph ‘,’ and punctuation ‘, ‘encrypt error ‘,’ decrypt ‘, ‘decrypt error’].

The function of translation will be discussed in the next module. We will first replace the Obtained Chinese content with random content.

4. Replace Chinese

Create a writable stream and replace the query with random characters.

// Create a writable stream to the file replacedesutils.ts
let writerStream = fs.createWriteStream('replaceDesUtils.ts');

readerStream.on('data', (chunk) => {

  var reg = /[\u4e00-\u9fa5]/g;
  let index = 0;
  let termList = [];    // Iterate over the Chinese array
  let term = ' ';

  while(list = reg.exec(chunk)) { ... Omit}if(termList && termList.length) {
    termList.map(item= > {
      data = data.replace(item, '112233');      // So far, all Chinese has been replaced
    })
  }

  writerStream.end(data); // Write the replaced file to replacedesutils.ts
})
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Now you can see that there is a replacedesutils.ts file under the current package. Open it and see if it is successful.

V. Realize translation function

In the call translation interface, reference to a nodejs based on the implementation of a Youdao dictionary translator baidu tutorial documents, friends can do reference.

Let me outline the steps to create the demo (there is 50 yuan in it, which is enough for us to write the demo test) :

Open Youdao Wisdom Cloud to register an account
On the left after logintabFound on theNatural language translation - Examples of translationTo create a new instance, selectText translation(Or you can choose another type, I just triedText translation)
Open on the lefttab 上Application management - My application, create a new application,Access typechooseAPIClick Next to bind the newly created instance.
Check out the app detailsApplication ID 和 Application of keyThese two fields correspond to what you’re going to need in a momentappKey 和 secretKey.

Next, create a translator.js file in that folder and copy it directly to create a Youdao Dictionary translator based on NodeJS.

[img-jqssvVM7-1578552563377] (gitImg/nodeReplace/1-5. JPG)

But this file has some libraries to use that we don’t have. We need to install it manually, and the steps are as follows:

1. Create one under the current packagepackage.jsonFile, copy the code:

{
  "dependencies": {
    "request": "^ 2.88.0"."request-promise": "^ 4.2.5." "}}Copy the code

2. Then run the following command on the terminal:npm ioryarnInstall the library we need.

Ok, go ahead and write our code in replace.js:

Import the translated file and instantiate it
Set the translation configuration
Write public methods to translate (if correctPromiseI don’t quite understand. I will explain it below.
Translate Chinese and write it into a document

var Translator = require('./translator');

let translator = new Translator();

translator.config = {
  from: 'zh_CHS'.to: 'EN'.appKey: '* * * * * * * * *'.secretKey: '* * * * * * * * * * * * * * * *'
}

function translateString(str) {
  return new Promise(function (resolve, reject) {
    letresultStr = translator.translate(str); resolve(resultStr); })}Copy the code

The translateString() method is explained here, because the translation interface we call is asynchronous and there are delays if we don’t use promises.

Promise provides an asynchronous execution mode.

The two arguments provided can be understood as return, and the required data is passed through resolve. Here’s a little test

translateString('come on').then(val= > {
  console.log(val);
})
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The resulting data is a long JSON string, which we escape and intercept. console.log(JSON.parse(val).translation)

Do you find that the translated content has been obtained by us?

Now let’s continue writing the code:

while(list = reg.exec(chunk)) { ... Omit} termList. Push (term);console.log(termList);    // Print Chinese data
translateString(termList).then(val= > {
  let translation = JSON.parse(val).translation;  // Here you can print the data and translate the content to see why the following code is written that way.
  let transList = [];     // The translated array

  if(translation[0] && translation[0].indexOf(', ')! = =- 1) {

    transList = translation[0].split(', '); // There is a space after the comma
    transList.map((item, index) = > {
      console.log(termList[index], item);
      const res = data.replace(termList[index], item);
      data = res;
    })

    writerStream.write(data, 'UTF8');
    writerStream.end();
    console.log('Write done'); }})Copy the code

Ok guys, now let’s open up replaceDesutils.ts and see what happens.

Later articles will use Express for text manipulation and you can upload custom files for translation.

NodeJs is used to translate JS/TS files

First, build the environment

Second, read the file

List all contents in Chinese

4. Replace Chinese

V. Realize translation function

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