natural-language-api-google/utils/sentiment.js

// Imports the Google Cloud client library
const language = require('@google-cloud/language').v2

// Creates a client
const client = new language.LanguageServiceClient()

const sentiment = async (text) => {

    // Prepares a document, representing the provided text
    const document = {
        content: text,
        type: 'PLAIN_TEXT',
    }  

    let status = null

    try {
        // Detects the sentiment of the document
        const [result] = await client.analyzeSentiment({ document })

        const sentiment = result.documentSentiment

        if (sentiment.score <= -0.25)
            status = 'negative'
        else if (sentiment.score <= 0.25)
            status = 'neutral'
        else
            status = 'positive' 

    } catch (error) {
        console.log(`Error in sentiment fuction on sentiment.js file: ${error}`)
    }

    return status
}

module.exports = sentiment