@digitowl/backend-utilities

Getting Started

Bind the dependencies

import { UtilitiesDependencies } from '@digitowl/backend-utilities';

const newContainer = new Container();

const registrationList = [
    // ...Other dependencies
    UtilitiesDependencies,
];

for (const reg of registrationList) {
    new reg().register(newContainer);
}

export const container = newContainer;

Bind the dependency types

import { UtilitiesDependencyTypes } from '@digitowl/backend-utilities';

export const types = {
    // ...Other dependency types
    ...UtilitiesDependencyTypes
}

Map errors

export class ExceptionToFailure {
    public failureMap = new Map<string, Map<string, boolean>>([
        [CoreFailureEnums.UPSTREAM_FAILURES, new Map<string, boolean>([
            ...CoreExceptionToFailure.failureMap.get(CoreFailureEnums.UPSTREAM_FAILURES),
            ...UtilityExceptionToFailure.failureMap.get(UtilityFailureEnums.UPSTREAM_FAILURES)
        ])],

        // ...Others failure mapping
    ]);

    // ...Converter function
}

JSONToCSVParserOperation

generateFile

The generateFile method is responsible for converting a given JSON data structure into a CSV formatted string, and then returning the resulting CSV content as a Buffer. The method uses a json2csv parser service that handles the parsing operation asynchronously

Example

const jsonData = [
    { name: "John", age: 30 },
    { name: "Jane", age: 25 }
];

// Read more: https://github.com/juanjoDiaz/json2csv/blob/main/packages/node/README.md#options-1
const parseOptions = {
    delimiter: ",",
    includeHeader: true,
    quoteChar: '"'
};

const csvBuffer = await jsonToCSVParserOperation.generateFile(jsonData, parseOptions);

// Do something with the buffer

JSZipFileCompressOperation

The JSZipFileCompressOperation class provides methods to create and manage ZIP files by adding files from external sources or in-memory buffers and generating the final compressed file. It leverages JSZip for ZIP file operations and uses fetch for downloading external resources.

addFileFromExternalSourceToZip

Adds a file from an external source to the ZIP file.

addFileFromBufferToZip

Adds a file from an in-memory buffer to the ZIP file.

generateFile

Generates the ZIP file and returns its content as a Node.js Buffer.

Example

...
@inject(types.iJSZipFileCompressOperation)
private zipFileCompressOperation: iJSZipFileCompressOperation,

await zipFileCompressOperation.addFileFromExternalSourceToZip({
    sourceExternalLink: "https://example.com/file.txt",
    destPathInZipFile: "folder/file.txt",
})

const fileBuffer = Buffer.from("Hello, world!");
await zipFileCompressOperation. .addFileFromBufferToZip({
    sourceFile: fileBuffer,
    destPathInZipFile: "hello.txt",
})

const zipBuffer = await this.zipFileCompressOperation.generateFile();

// Do something with the zip buffer

PuppeteerHeadlessBrowserOperation

The PuppeteerHeadlessBrowserOperation class provides functionality to generate a PDF file from an EJS template using Puppeteer, a headless browser automation library. This class is designed to handle the entire flow from rendering an EJS template to creating a PDF document.

generatePDFFromEJSTemplate

Generates a PDF from an EJS template with the provided data and PDF options.

Example

@inject(types.iPuppeteerHeadlessBrowserOperation)
private puppeteerHeadlessBrowserOperation: iPuppeteerHeadlessBrowserOperation,

const templatePath = "path/to/template.ejs";
const data = { title: "Sample Title", content: "Sample Content" };
const pdfOptions = { format: "A4", printBackground: true };

await this.puppeteerHeadlessBrowserOperation.generatePDFFromEJSTemplate(
    templatePath,
    data,
    pdfOptions
)