ludown-library.md

Ludown as a library

Ludown can be used within a Node.js application as an imported library. Install locally:

npm install ludown --save

Parsing lu files

To parse LU files, you can use the parseFile() method.

const ludown = require('ludown');
const luContent1 = `# Greeting
- hi`;
const log = false;
const locale = 'en-us';
ludown.parser.parseFile(luContent1, log, locale)
    .then(function(parsedContent) {
        // Parsed LUIS object
        console.log(JSON.stringify(parsedContent.LUISJsonStructure, 2, null));
        // Parsed QnA content
        console.log(JSON.stringify(parsedContent.additionalFilesToParse, 2, null));
        // Additional files to parse
        console.log(JSON.stringify(parsedContent.additionalFilesToParse, 2, null));
    })
    .catch(function(err) {
        let errObj = new ludown.helperClasses.Exception(err);
        // err is of type ludown.helperClasses.Exception. 
        // Possible error codes are available under ludown.helperEnums.errorCodes
        if(errObj.errCode === ludown.helperEnums.errorCodes.INVALID_INPUT) {
            // do something specific to this error code
        } else {
            console.log(errObj.text);
        }
    })

Validating parsed lu files

You can use the available validateLUISBlob() function to verify if the parsed LUIS blob is valid. This helps catch name conflicts, invalid labelled utterances etc.

const ludown = require('ludown');
const luContent = `# Greeting
- hi {userName=bob}
$userName:first=
-vishwac`;
const log = false;
const locale = 'en-us';
async function parseContent() {
    let parsedContent;
    try {
        parsedContent = await ludown.parser.parseFile(luContent, log, locale);
    } catch (err) {
        let errObj = new ludown.helperClasses.Exception(err);
        // err is of type ludown.helperClasses.Exception. 
        // Possible error codes are available under ludown.helperEnums.errorCodes
        if(errObj.errCode === ludown.helperEnums.errorCodes.INVALID_INPUT) {
            // do something specific to this error code
        } else {
            console.log(errObj.text);
        }
    }
    // validate the parsed luis content
    ludown.parser.validateLUISBlob(parsedContent.LUISJsonStructure)
        .then(res => res)
        .catch(function(err) {
            let exception = new ludown.helperClasses.Exception(err);
            console.error('Oops, invalid LUIS content!\n');
            console.error(exception.errCode + ' : ' + exception.text);
        })
}

parseContent();

Generating lu content from LUIS JSON

You can generate lu content from LUIS and QnA maker JSON using constructMdFromLUIS() and constructMdFromQnA() methods. Here's an example code snippet.

#!/usr/bin/env node
const ludown = require('ludown');
const luContent = `# Greeting
- hi
$userName:first=
-vishwac`;
const log = false;
const locale = 'en-us';
async function parseContent() {
    let parsedContent;
    try {
        parsedContent = await ludown.parser.parseFile(luContent, log, locale);
    } catch (err) {
        let errObj = new ludown.helperClasses.Exception(err);
        // err is of type ludown.helperClasses.Exception. 
        // Possible error codes are available under ludown.helperEnums.errorCodes
        if(errObj.errCode === ludown.helperEnums.errorCodes.INVALID_INPUT) {
            // do something specific to this error code
        } else {
            console.log(errObj.text);
        }
    }
    
    if(await ludown.parser.validateLUISBlob(parsedContent.LUISJsonStructure)) {
        // reconstruct md content
        ludown.refresh.constructMdFromLUIS(parsedContent.LUISJsonStructure)
        .then(function(result){
            console.log(result);
        })
        .catch(function(err) {
            let exception = new ludown.helperClasses.Exception(err);
            console.error('Oops, invalid LUIS content!\n');
            console.error(exception.errCode + ' : ' + exception.text);
        })
    }

}

parseContent();

Translating lu files

You can take advantage of the Microsoft text translation API to automatically machine translate .lu files to one or more than 60+ languages supported by the Microsoft text translation cognitive service.

To translate lu file content, you can simply use the parseAndTranslate() method. Here's a code snippet.

const ludown = require('ludown');
const luContent = `# Greeting
- hi
$userName:first=
-vishwac`;
const log = false;
const targetLanguage = 'de';
const subscriptionKey = '<YOUR TEXT TRANSLATION KEY>';
const translateComments = true;
const translateLinkText = true;
ludown.translate.parseAndTranslate(luContent, subscriptionKey, targetLanguage, '', translateComments, translateLinkText, log)
    .then(function(result) {
        console.log(result);
    })
    .catch(function(err){
        let exception = new ludown.helperClasses.Exception(err);
        console.error(exception.errCode + ' : ' + exception.text);
    })