handlebars.js VS puppeteer

If you have a bit of Nodejs SSR background, you would already be accustomed to templating libraries like Pug, Handlebars, EJS, etc. If you’re from a PHP background you would be familiar with the Blade templating engine. These templating libraries basically help you render dynamic data from the backend on the frontend. They also help you generate markup with loops based on conditions.

It’s time to create our code template. To do this, we use handlebars js, which allows us to create templates at a basic level. We create a folder called templates in the project home directory and add our template files inside.

Templating engine: SSGs rely on templating engines to define the structure of web pages. These engines enable developers to create reusable templates and incorporate dynamic content. Popular templating engines include Liquid, Handlebars, Mustache, EJS, ERB, HAML, and Slim.

Here's our first usage of the handlebars (docs) template. The .hbs extension will be removed once we run the action. Inside index.ts.hbs, add:

Id use handlerbars JS - https://handlebarsjs.com/

Node.js programming language will be used for simplicity. Handlebars template engine to separate data from the presentation. html2pdf.app to convert HTML to PDF, but as an alternative Puppeteer can be used also (you can find a complete tutorial How to convert HTML to PDF with puppeteer).

Handlebars.js site

But a valid question is: Why not use a template like Handlebars? For the use case inside Woovi, templates won't help us because we would need two core points: reuse our design system and ensure the usage of GraphQL in our payment link.

You might want to brush up on https://handlebarsjs.com/ if you want to make templates.

Once the package is set up, it will provide a MailService class that has a method named sendEmail that will receive some parameters and then send the mail. But first, we need to create the mail template and for that, we will use handlebars. It will allow us, to create HTML templates in which we can pass dynamics parameters, such as the user name or its information, and write inline CSS to style our email.

I am not in any way associated with the developers at puppeteer, but if you are looking for a way to contribute, they are open source

With the advent of tools like Puppeteer and now Playwright, end-to-end testing has become much easier and more reliable. For anyone who's used Selenium in the past, you know what I'm talking about. Puppeteer has opened the way in terms of E2E tooling, but Playwright has taken it to the next level and made it easier to await for certain selectors or conditions to be fulfilled (via locators), thus making tests more reliable and less flaky. Also, it's a game changer that it introduced a test-runner - this made the integration between the headless browser and the actual test code much smoother.

1.Puppeteer: Puppeteer is a Node library that provides a high-level API to control headless Chrome or Chromium using the DevTools Protocol. Key Features: More control over Chrome. Enables web scraping. Allows taking screenshots and generating PDFs for UI testing. Measures load times through the Chrome Performance Analysis tool

HTML to PDF conversion is a common requirement in modern web applications. It allows users to save web pages, reports, and other content in a format that is easy to share and print. There are many libraries and services available for converting HTML to PDF, each with its own strengths and weaknesses. In this article, we will compare some of the most popular HTML to PDF renderers in Node.js, including Puppeteer, Playwright, node-html-pdf, and Onedoc.

Playwright seems to be a superior library for working with headless browsers than Puppeteer, but I will go with Puppeteer.

Puppeteer is a Node library that provides a high-level API to control headless Chrome or Chromium. It's primarily used for browser automation, making it a powerful tool for end-to-end testing of web applications, taking screenshots, and generating pre-rendered content from web pages.

Puppeteer

Website: pptr.dev Repositório: GitHub

# Define variables PYTHON := python3 POETRY := poetry PYTEST := pytest PIP := pip3 PROJECT_NAME := web automation with Pyppeteer .PHONY: install install: $(POETRY) install @echo "Dependency installation complete" $(PIP) install -r requirements.txt @echo "Set env vars LT_USERNAME & LT_ACCESS_KEY" # Procure Username and AccessKey from https://accounts.lambdatest.com/security export LT_USERNAME=himansh export LT_ACCESS_KEY=Ia1MiqNfci .PHONY: install poetry-install: poetry install .PHONY: test test: export NODE_ENV = test .PHONY: test pyunit-pyppeteer: - echo $(EXEC_PLATFORM) - $(PYTHON) tests/pyunit-pyppeteer/test_pyunit_pyppeteer.py .PHONY: test pytest-pyppeteer: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s -n 2 tests/pytest-pyppeteer/test_pytest_pyppeteer_1.py \ tests/pytest-pyppeteer/test_pytest_pyppeteer_2.py .PHONY: test pyunit-pyppeteer-browser-session: - echo $(EXEC_PLATFORM) - $(PYTHON) tests/starting-browser-session/pyunit/test_pyppeteer_browser_session.py .PHONY: test pytest-pyppeteer-browser-session: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s \ tests/starting-browser-session/pytest/test_pyppeteer_browser_session.py .PHONY: test asyncio-run-pyppeteer-browser-session: - echo $(EXEC_PLATFORM) - $(PYTHON) tests/starting-browser-session/asyncio_run/test_pyppeteer_browser_session.py .PHONY: test asyncio-run-complete-pyppeteer-browser-session: - echo $(EXEC_PLATFORM) - $(PYTHON) tests/starting-browser-session/\ asyncio_run_until_complete/test_pyppeteer_browser_session.py .PHONY: test pyppeteer-button-click: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/button-click/test_page_class_click.py .PHONY: test pyppeteer-activate-tab: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/active-tab/test_page_class_bringtofront.py ###### Testing Custom Environment - https://miyakogi.github.io/pyppeteer/reference.html#environment-variables # Available versions: 113, 121, and default .PHONY: test pyppeteer-custom-chromium-version: - echo $(EXEC_PLATFORM) - echo 'Browser Version:' $(CHROMIUM_VERSION) - $(PYTEST) --verbose --capture=no -s tests/custom-configuration/test_launcher_exe_path.py ###### Testing Headless - https://miyakogi.github.io/pyppeteer/reference.html#launcher # Available values: headless and non-headless .PHONY: test pyppeteer-custom-browser-mode: - echo $(EXEC_PLATFORM) - echo $(BROWSER_MODE) - $(PYTEST) --verbose --capture=no -s tests/custom-configuration/test_launcher_headless.py .PHONY: test pyppeteer-generate-pdf: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/generate-pdf/test_page_class_pdf.py .PHONY: test pyppeteer-generate-screenshot: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/generate-screenshots/test_page_class_screenshot.py .PHONY: test pyppeteer-cookies: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/handling-cookies/test_page_class_cookies.py .PHONY: test pyppeteer-dialog-box: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/handling-dialog-box/test_handling_dialog_box.py .PHONY: test pyppeteer-iframe: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/handling-iframe/test_page_class_iframe.py # Like Puppeteer, Navigation operations mentioned below only work in Headless mode # goBack: https://miyakogi.github.io/pyppeteer/reference.html#pyppeteer.page.Page.goBack # goForward: https://miyakogi.github.io/pyppeteer/reference.html#pyppeteer.page.Page.goForward # Bug Link # https://github.com/puppeteer/puppeteer/issues/7739 # https://stackoverflow.com/questions/65540674/how-to-error-check-pyppeteer-page-goback .PHONY: test pyppeteer-navigate-ops: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/navigate-operations/test_page_class_navigation_ops.py .PHONY: test pyppeteer-request-response: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/request-response/test_page_class_req_resp.py .PHONY: test pyppeteer-viewport: - echo $(EXEC_PLATFORM) - echo $(BROWSER_MODE) - $(PYTEST) --verbose --capture=no -s tests/setting-useragent-viewports/\ test_page_class_useragent_viewport.py::test_mod_viewport .PHONY: test pyppeteer-non-headless-useragent: - echo $(EXEC_PLATFORM) - echo $(BROWSER_MODE) - $(PYTEST) --verbose --capture=no -s tests/setting-useragent-viewports/\ test_page_class_useragent_viewport.py::test_get_nonheadless_user_agent .PHONY: test pyppeteer-headless-useragent: - echo $(EXEC_PLATFORM) - echo $(BROWSER_MODE) - $(PYTEST) --verbose --capture=no -s tests/setting-useragent-viewports/\ test_page_class_useragent_viewport.py::test_get_headless_user_agent .PHONY: test pyppeteer-dynamic-content: - echo $(EXEC_PLATFORM) - echo $(BROWSER_MODE) - $(PYTEST) --verbose --capture=no -s -n 4 tests/handling-dynamic-content/\ test_page_class_lazy_loaded_content.py .PHONY: test pyppeteer-web-scraping: - echo $(EXEC_PLATFORM) - $(PYTEST) --verbose --capture=no -s tests/web-scraping-content/\ test_scraping_with_pyppeteer.py .PHONY: clean clean: # This helped: https://gist.github.com/hbsdev/a17deea814bc10197285 find . | grep -E "(__pycache__|\.pyc$$)" | xargs rm -rf rm -rf .pytest_cache/ @echo "Clean Succeeded" .PHONY: distclean distclean: clean rm -rf venv .PHONY: help help: @echo "" @echo "install : Install project dependencies" @echo "clean : Clean up temp files" @echo "pyunit-pyppeteer : Running Pyppeteer tests with Pyunit framework" @echo "pytest-pyppeteer : Running Pyppeteer tests with Pytest framework" @echo "pyunit-pyppeteer-browser-session : Browser session using Pyppeteer and Pyunit" @echo "pytest-pyppeteer-browser-session : Browser session using Pyppeteer and Pytest" @echo "asyncio-run-pyppeteer-browser-session : Browser session using Pyppeteer (Approach 1)" @echo "asyncio-run-complete-pyppeteer-browser-session : Browser session using Pyppeteer (Approach 2)" @echo "pyppeteer-button-click : Button click demo using Pyppeteer" @echo "pyppeteer-activate-tab : Switching browser tabs using Pyppeteer" @echo "pyppeteer-custom-chromium-version : Custom Chromium version with Pyppeteer" @echo "pyppeteer-custom-browser-mode : Headless and non-headless test execution with Pyppeteer" @echo "pyppeteer-generate-pdf : Generating pdf using Pyppeteer" @echo "pyppeteer-generate-screenshot : Generating page & element screenshots with Pyppeteer" @echo "pyppeteer-cookies : Customizing cookies with Pyppeteer" @echo "pyppeteer-dialog-box : Handling Dialog boxes with Pyppeteer" @echo "pyppeteer-iframe : Handling iFrames with Pyppeteer" @echo "pyppeteer-navigate-ops : Back & Forward browser operations with Pyppeteer" @echo "pyppeteer-request-response : Request and Response demonstration using Pyppeteer" @echo "pyppeteer-viewport : Customizing viewports using Pyppeteer" @echo "pyppeteer-non-headless-useragent : Customizing user-agent (with browser in headed mode) using Pyppeteer" @echo "pyppeteer-headless-useragent : Customizing user-agent (with browser in headless mode) using Pyppeteer" @echo "pyppeteer-dynamic-content : Handling dynamic web content using Pyppeteer" @echo "pyppeteer-web-scraping : Dynamic web scraping using Pyppeteer"

This library works by creating an instance of WhatsApp web running inside an instance of headless chrome automated by puppeteer. In my testing, I ran into tons of compatibility issues when trying to use these dependencies inside anything other than a bare-bones Node.js + express server. Also, we can’t spin up a new instance of chrome and WhatsApp web each time a user sends a message, this will exhaust our allowed WhatsApp connections (4 max), not to mention that doing this will make the response times painfully slow.