Javascript

Cypress testing your IndexedDb contents with @this-dot/cypress-indexeddb

Published Jan 6, 2022

Updated Feb 13, 2023

4 min read

This article was written over 18 months ago and may contain information that is out of date. Some content may be relevant but please refer to the relevant official documentation or available resources for the latest information.

IndexedDb is a browser API for storing significant amounts of structured data locally. It is very useful when you are working on a PWA, and you need to support offline mode. Developers have been using IndexedDb to store the data changes while the user is offline, and to send those to the server when the user goes online again. But that is not the only use-case. Sometimes, there are very long forms that need to be saved locally so if the user refreshes or comes back later the previously entered data is not lost. The same scenario can be useful for a web shop's checkout logic, so users can go back to their abandoned shopping carts weeks later even.

Whether you implement your IndexedDb logic, or you use a wrapper library, such as localforage to handle IndexedDb for you, it is not that straightforward to test these implementations. If you would like to check out the source code, feel free to visit our repository.

Our example application

For our example, we have a simple user form with a few input fields. This form saves every entry that comes from the user. It uses a debounce logic that waits for 1 second before saving the form contents into indexedDb. When the user submits the form, it waits for the last write operation. After that finishes, it submits the form and then clears the indexedDb. If the proper fields are saved to the database, and if the user opens this page, those values are loaded.

This example application uses localforage to populate IndexedDb. The database name is FORM_CACHE and will have a keyvaluepairs object-store created by localforage. Inside the object-store, we will use the user_form key to store the values. Let's write our tests!

Installing the plugin

To use the helper functions, we need to install the package first.

npm install @this-dot/cypress-indexeddb

After the install finishes, go inside your Cypress support folder, and add the following line to your commands.ts file:

import '@this-dot/cypress-indexeddb';

Create a cypress-indexeddb-namespace.ts file inside the same support folder, and add the following typings:

  declare namespace Cypress {
    interface Chainable<Subject> {
      clearIndexedDb(databaseName: string): void;
      openIndexedDb(databaseName: string, version?: number): Chainable<IDBDatabase>;
      createObjectStore(storeName: string): Chainable<IDBObjectStore>;
      getStore(storeName: string): Chainable<IDBObjectStore>;
      createItem(key: string, value: unknown): Chainable<IDBObjectStore>;
      readItem<T = unknown>(key: IDBValidKey | IDBKeyRange): Chainable<T>;
      updateItem(key: string, value: unknown): Chainable<IDBObjectStore>;
      deleteItem(key: string): Chainable<IDBObjectStore>;
    }
  }

Finally, import the cypress-indexeddb-namespace.ts contents in the index.ts file of the same support folder.

import './commands';
import './namespace';

Now that you are all set up, you can use the commands in your tests.

Test setup

Since IndexedDb stores data locally, it is imperative to delete previous databases before every test run. That way, we can make sure that the tests run in isolation, and data from other tests won't leak out. After deleting the database, we also want to set up the connections so we can access and manipulate the database in our tests later.

describe(`User Form`, () => {

  beforeEach(() => {
    cy.clearIndexedDb('FORM_CACHE');
    cy.openIndexedDb('FORM_CACHE')
      .as('formCacheDB')
      .createObjectStore('keyvaluepairs')
      .as('objectStore');
  })

});

When we open a connection to the FORM_CACHE database and create the keyvaluepairs object-store, we can use the .as() method to alias them for later access. The .get() command could not be overwritten, so we have the getIndexedDb and the getStore methods to retrieve them.

Reading from the database

We have our before hook, so let's test the saving functionality of the form. We enter some values into the form with cypress, then we wait for the debounced write operation. After that, we simply access the database, read the contents and assert them.

describe(`User Form`, () => {

  // beforeEach

  it(`entering data into the form saves it to the indexedDb`, () => {
    cy.visit('/user-form');

    cy.get('#firstName').should('be.visible').type('Hans');
    cy.get('#lastName').should('be.visible').type('Gruber');
    cy.get('#country').should('be.visible').type('Germany');
    cy.get('#city').should('be.visible').type('Berlin');

    cy.log('Waiting for the debounceTime to start a db write').wait(1100);

    cy.getStore('@objectStore').readItem('user_form').should('deep.equal', {
      firstName: 'Hans',
      lastName: 'Gruber',
      country: 'Germany',
      city: 'Berlin',
      address: '',
      addressOptional: '',
    });
  });

});

We can use the .getStore('@objectStore') method to retrieve a previously aliased store instance for ourselves. The .readItem(key) method retrieves the contents of that key in the store. We can use the .should() method to assert the retrieved value. Here we use the deep.equal assertion.

Deleting from the database

Sometimes users delete everything that is stored locally. They can do it from the developer tools, or maybe they run clean-up software that removes these for them. Anyways, if something like that happens, they cannot get back to the state they left the form in. Let's simulate it by deleting items from the database.

describe(`User Form`, () => {

  // beforeEach

  it(`when the indexedDb is deleted manually and then the page reloaded, the form does not populate`, () => {
    cy.visit('/user-form');

    cy.get('#firstName').should('be.visible').type('Hans');
    cy.get('#lastName').should('be.visible').type('Gruber');
    cy.get('#country').should('be.visible').type('Germany');
    cy.get('#city').should('be.visible').type('Berlin');

    cy.log('Waiting for the debounceTime to start a db write').wait(1100);

    cy.log('user manually clears the IndexedDb')
      .getStore('@objectStore')
      .deleteItem('user_form')
      .reload();

    cy.get('#firstName').should('be.visible').and('have.value', '');
    cy.get('#lastName').should('be.visible').and('have.value', '');
    cy.get('#country').should('be.visible').and('have.value', '');
    cy.get('#city').should('be.visible').and('have.value', '');
  });

});

We again get the previously aliased store and we call the .deleteItem(key) method on it. After that, we can chain other cypress methods off. For example, we reload the page in this particular test.

Adding data to the database

We can see that if we empty the database, the values won't load into the form. We should write a test to populate these values before loading the page and test if they are loaded into the form properly.

describe(`User Form`, () => {

  // beforeEach

  it(`when there is relevant data in the indexedDb, the form gets populated when the page opens`, () => {
    cy.getStore('@objectStore').createItem('user_form', {
      firstName: 'John',
      lastName: 'McClane',
      country: 'USA',
      city: 'New York',
    });

    cy.visit('/user-form');

    cy.get('#firstName').should('be.visible').and('have.value', 'John');
    cy.get('#lastName').should('be.visible').and('have.value', 'McClane');
    cy.get('#country').should('be.visible').and('have.value', 'USA');
    cy.get('#city').should('be.visible').and('have.value', 'New York');
  });

});

We can call the .createItem(key, value) method to populate the provided key in an object-store. We can use any value.

Testing if our code clears the database properly

We can create/update and read data in our database. We can even delete values from it using our library, but what about testing our code? We have a wrapper class around localforage in the codebase that handles database deletion on submit. We should test that functionality as well!

describe(`User Form`, () => {

  // beforeEach

  it(`submitting the form clears the indexedDb`, () => {
    cy.getStore('@objectStore').createItem('user_form', {
      firstName: 'John',
      lastName: 'McClane',
      country: 'USA',
      city: 'New York',
    });

    cy.visit('/user-form');

    cy.get('#address').type('23rd Street 12');
    cy.get(`[data-test-id="submit button"]`).should('be.visible').and('not.be.disabled').click();

    cy.log('Waiting for the save event and DB write to occur').wait(1100);

    cy.getStore('@objectStore').readItem('user_form').should('be.undefined');
  });

});

We use the .createItem() method to make sure that there are values populated into the database. Then, we use cypress to make our app put some other values into the database. After, we submit the form we wait for the debounce handlers to handle the operations and lastly, we validate that the value that we previously populated should now be undefined.

How to run the above tests

If you would like to see it in action, please check out our git repository. After running npm install you should be able to start the tests by running the npm run e2e:debug command.

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About the author(s)

Balázs Tápai
He is a Software Engineer with a passion for automated testing. He loves Angular on the Front-End and NestJS on the Back-End. He also uses Cypress to reduce developer anxiety before demo meetings.
@TapaiBalazs @TapaiBalazs

Introduction to Zod for Data Validation

As web developers, we're often working with data from external sources like APIs we don't control or user inputs submitted to our backends. We can't always rely on this data to take the form we expect, and we can encounter unexpected errors when it deviates from expectations. But with the Zod library, we can define what our data ought to look like and parse the incoming data against those defined schemas. This lets us work with that data confidently, or to quickly throw an error when it isn't correct. Why use Zod? TypeScript is great for letting us define the shape of our data in our code. It helps us write more correct code the first time around by warning us if we are doing something we shouldn't. But TypeScript can't do everything for us. For example, we can define a variable as a string or a number, but we can't say "a string that starts with user_id_ and is 20 characters long" or "an integer between 1 and 5". There are limits to how much TypeScript can narrow down our data for us. Also, TypeScript is a tool for us developers. When we compile our code, our types are not available to the vanilla JavaScript. JavaScript can't validate that the data we actually use in our code matches what we thought we'd get when we wrote our TypeScript types unless you're willing to manually write code to perform those checks. This is where we can reach for a tool like Zod. With Zod, we can write data schemas. These schemas, in the simplest scenarios, look very much like TypeScript types. But we can do more with Zod than we can with TypeScript alone. Zod schemas let us create additional rules for data parsing and validation. A 20-character string that starts with user_id_? It's z.string().startsWith('user_id_').length(20). An integer between 1 and 5 inclusive? It's z.number().int().gte(1).lte(5). Zod's primitives give us many extra functions to be more specific about *exactly* what data we expect. Unlike TypeScript, Zod schemas aren't removed on compilation to JavaScript—we still have access to them! If our app receives some data, we can verify that it matches the expected shape by passing it to your Zod schema's parse function. You'll either get back your data in exactly the shape you defined in your schema, or Zod will give you an error to tell you what was wrong. Zod schemas aren't a replacement for TypeScript; rather, they are an excellent complement. Once we've defined our Zod schema, it's simple to derive a TypeScript type from it and to use that type as we normally would. But when we really need to be sure our data conforms to the schema, we can always parse the data with our schema for that extra confidence. Defining Data Schemas Zod schemas are the variables that define our expectations for the shape of our data, validate those expectations, and transform the data if necessary to match our desired shape. It's easy to start with simple schemas, and to add complexity as required. Zod provides different functions that represent data structures and related validation options, which can be combined to create larger schemas. In many cases, you'll probably be building a schema for a data object with properties of some primitive type. For example, here's a schema that would validate a JavaScript object representing an order for a pizza: ` Zod provides a number of primitives for defining schemas that line up with JavaScript primitives: string, number, bigint, boolean, date, symbol, undefined, and null. It also includes primitives void, any, unknown, and never for additional typing information. In addition to basic primitives, Zod can define object, array, and other native data structure schemas, as well as schemas for data structures not natively part of JavaScript like tuple and enum. The documentation contains considerable detail on the available data structures and how to use them. Parsing and Validating Data with Schemas With Zod schemas, you're not only telling your program what data should look like; you're also creating the tools to easily verify that the incoming data matches the schema definitions. This is where Zod really shines, as it greatly simplifies the process of validating data like user inputs or third party API responses. Let's say you're writing a website form to register new users. At a minimum, you'll need to make sure the new user's email address is a valid email address. For a password, we'll ask for something at least 8 characters long and including one letter, one number, and one special character. (Yes, this is not really the best way to write strong passwords; but for the sake of showing off how Zod works, we're going with it.) We'll also ask the user to confirm their password by typing it twice. First, let's create a Zod schema to model these inputs: ` So far, this schema is pretty basic. It's only making sure that whatever the user types as an email is an email, and it's checking that the password is at least 8 characters long. But it is *not* checking if password and confirmPassword match, nor checking for the complexity requirements. Let's enhance our schema to fix that! ` By adding refine with a custom validation function, we have been able to verify that the passwords match. If they don't, parsing will give us an error to let us know that the data was invalid. We can also chain refine functions to add checks for our password complexity rules: ` Here we've chained multiple refine functions. You could alternatively use superRefine, which gives you even more fine grained control. Now that we've built out our schema and added refinements for extra validation, we can parse some user inputs. Let's see two test cases: one that's bound to fail, and one that will succeed. ` There are two main ways we can use our schema to validate our data: parse and safeParse. The main difference is that parse will throw an error if validation fails, while safeParse will return an object with a success property of either true or false, and either a data property with your parsed data or an error property with the details of a ZodError explaining why the parsing failed. In the case of our example data, userInput2 will parse just fine and return the data for you to use. But userInput1 will create a ZodError listing all of the ways it has failed validation. ` ` We can use these error messages to communicate to the user how they need to fix their form inputs if validation fails. Each error in the list describes the validation failure and gives us a human readable message to go with it. You'll notice that the validation errors for checking for a valid email and for checking password length have a lot of details, but we've got three items at the end of the error list that don't really tell us anything useful: just a custom error of Invalid input. The first is from our refine checking if the passwords match, and the second two are from our refine functions checking for password complexity (numbers and special characters). Let's modify our refine functions so that these errors are useful! We'll add our own error parameters to customize the message we get back and the path to the data that failed validation. ` Now, our error messages from failures in refine are informative! You can figure out which form fields aren't validating from the path, and then display the messages next to form fields to let the user know how to remedy the error. ` By giving our refine checks a custom path and message, we can make better use of the returned errors. In this case, we can highlight specific problem form fields for the user and give them the message about what is wrong. Integrating with TypeScript Integrating Zod with TypeScript is very easy. 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Typically you have to move the current focus to the active dialog when showing them, but with the dialog element that’s done for you. By default, the focus will be set on the first focusable element in the dialog. You can optionally change which element receives focus first by setting the autofocus attribute on the element you want the focus to start on, as seen in the previous example where that attribute was added to the close element. Using the .showModal() method to open the dialog also implicitly adds the dialog ARIA role to the dialog element. This helps screen readers understand that a modal has appeared and the screen so it can act accordingly. Adding forms to dialogs Forms can also be added to dialogs, and there’s even a special method value for them. If you add a element with the method set to dialog then the form will have some different behaviors that differ from the standard get and post form methods. First off, no external HTTP request will be made with this new method. 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How to host a full-stack app with AWS CloudFront and Elastic Beanstalk

How to host a full-stack JavaScript app with AWS CloudFront and Elastic Beanstalk Let's imagine that you have finished building your app. You have a Single Page Application (SPA) with a NestJS back-end. You are ready to launch, but what if your app is a hit, and you need to be prepared to serve thousands of users? You might need to scale your API horizontally, which means that to serve traffic, you need to have more instances running behind a load balancer. Serving your front-end using a CDN will also be helpful. In this article, I am going to give you steps on how to set up a scalable distribution in AWS, using S3, CloudFront and Elastic Beanstalk. The NestJS API and the simple front-end are both inside an NX monorepo The sample application For the sake of this tutorial, we have put together a very simple HTML page that tries to reach an API endpoint and a very basic API written in NestJS. The UI The UI code is very simple. 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For example, if this is going to be your production deployment I recommend having -prod in the name so you will be able to see at a glance, that this bucket contains your production front-end and nothing should get deleted accidentally. We go with the defaults for this bucket setting it to the us-east-1 region. Let's set up the bucket to block all public access, because we are going to allow get requests through CloudFront to these files. We don't need bucket versioning enabled, because these files will be deleted every time a new front-end version will be uploaded to this bucket. If we were to enable bucket versioning, old front-end files would be marked as deleted and kept, increasing the storage costs in the long run. Let's use server-side encryption with Amazon S3-managed keys and create the bucket. When the bucket is created, upload the front-end files to the bucket and let's go to the CloudFront service and create a distribution. As the origin domain, choose your S3 bucket. Feel free to change the name for the origin. For Origin access, choose the Origin access control settings (recommended). Create a new Control setting with the defaults. I recommend adding a description to describe this control setting. At the Web Application Firewall (WAF) settings we would recommend enabling security protections, although it has cost implications. For this tutorial, we chose not to enable WAF for this CloudFront distribution. In the Settings section, please choose the Price class that best fits you. If you have a domain and an SSL certificate you can set those up for this distribution, but you can do that later as well. As the Default root object, please provide index.html and create the distribution. When you have created the distribution, you should see a warning at the top of the page. Copy the policy and go to your S3 bucket's Permissions tab. Edit the Bucket policy and paste the policy you just copied, then save it. If you have set up a domain with your CloudFront distribution, you can open that domain and you should be able to see our front-end deployed. If you didn't set up a domain the Details section of your CloudFront distribution contains your distribution domain name. If you click on the "Hello" button on your deployed front-end, it should not be able to reach the /api/hello endpoint and should display an error message on the page. Hosting the API in Elastic Beanstalk Elastic beanstalk prerequisites For our NestJS API to run in Elastic Beanstalk, we need some additional setup. Inside the apps/api/src folder, let's create a Procfile with the contents: web: node main.js. Then open the apps/api/project.json and under the build configuration, extend the production build setup with the following (I only ) ` The above settings will make sure that when we build the API with a production configuration, it will generate a package.json and a package-lock.json near the output file main.js. To have a production-ready API, we set up a script in the package.json file of the repository. Running this will create a dist/apps/api and a dist/apps/frontend folder with the necessary files. ` After running the script, zip the production-ready api folder so we can upload it to Elastic Beanstalk later. ` Creating the Elastic Beanstalk Environment Let's open the Elastic Beanstalk service in the AWS console. And create an application. An application is a logical grouping of several environments. We usually put our development, staging and production environments under the same application name. The first time you are going to create an application you will need to create an environment as well. We are creating a Web server environment. Provide your application's name in the Application information section. You could also provide some unique tags for your convenience. In the Environment information section please provide information on your environment. Leave the Domain field blank for an autogenerated value. When setting up the platform, we are going to use the Managed Node.js platform with version 18 and with the latest platform version. Let's upload our application code, and name the version to indicate that it was built locally. This version label will be displayed on the running environment and when we set up automatic deployments we can validate if the build was successful. As a Preset, let's choose Single instance (free tier eligible) On the next screen configure your service access. For this tutorial, we only create a new service-role. You must select the aws-elasticbeanstalk-ec2-role for the EC2 instance profile. If can't select this role, you should create it in AWS IAM with the AWSElasticBeanstalkWebTier, AWSElasticBeanstalkMulticontainerDocker and the AWSElasticBeanstalkRoleWorkerTier managed permissions. The next step is to set up the VPC. For this tutorial, I chose the default VPC that is already present with my AWS account, but you can create your own VPC and customise it. In the Instance settings section, we want our API to have a public IP address, so it can be reached from the internet, and we can route to it from CloudFront. Select all the instance subnets and availability zones you want to have for your APIs. For now, we are not going to set up a database. We can set it up later in AWS RDS but in this tutorial, we would like to focus on setting up the distribution. Let's move forward Let's configure the instance traffic and scaling. This is where we are going to set up the load balancer. In this tutorial, we are keeping to the defaults, therefore, we add the EC2 instances to the default security group. In the Capacity section we set the Environment type to Load balanced. This will bring up a load balancer for this environment. Let's set it up so that if the traffic is large, AWS can spin up two other instances for us. Please select your preferred tier in the instance types section, We only set this to t3.micro For this tutorial, but you might need to use larger tiers. Configure the Scaling triggers to your needs, we are going to leave them as defaults. Set the load balancer's visibility to the public and use the same subnets that you have used before. At the Load Balancer Type section, choose Application load balancer and select Dedicated for exactly this environment. Let's set up the listeners, to support HTTPS. Add a new listener for the 443 port and connect your SSL certificate that you have set up in CloudFront as well. For the SSL policy choose something that is over TLS 1.2 and connect this port to the default process. Now let's update the default process and set up the health check endpoint. We set up our API to have the health check endpoint at the /api route. Let's modify the default process accordingly and set its port to 8080. For this tutorial, we decided not to enable log file access, but if you need it, please set it up with a separate S3 bucket. At the last step of configuring your Elastic Beanstalk environment, please set up Monitoring, CloudWatch logs and Managed platform updates to your needs. For the sake of this tutorial, we have turned most of these options off. Set up e-mail notifications to your dedicated alert e-mail and select how you would like to do your application deployments. At the end, let's configure the Environment properties. We have set the default process to occupy port 8080, therefore, we need to set up the PORT environment variable to 8080. Review your configuration and then create your environment. It might take a few minutes to set everything up. After the environment's health transitions to OK you can go to AWS EC2 / Load balancers in your web console. If you select the freshly created load balancer, you can copy the DNS name and test if it works by appending /api/hello at the end of it. Connect CloudFront to the API endpoint Let's go back to our CloudFront distribution and select the Origins tab, then create a new origin. Copy your load balancer's URL into the Origin domain field and select HTTPS only protocol if you have set up your SSL certificate previously. If you don't have an SSL certificate set up, you might use HTTP only, but please know that it is not secure and it is especially not recommended in production. We also renamed this origin to API. Leave everything else as default and create a new origin. Under the Behaviors tab, create a new behavior. Set up the path pattern as /api/* and select your newly created API origin. At the Viewer protocol policy select Redirect HTTP to HTTPS and allow all HTTP methods (GET, HEAD, OPTIONS, PUT, POST, PATCH, DELETE). For this tutorial, we have left everything else as default, but please select the Cache Policy and Origin request policy that suits you the best. Now if you visit your deployment, when you click on the HELLO button, it should no longer attach an error message to the DOM. --- Now we have a distribution that serves the front-end static files through CloudFront, leveraging caching and CDN, and we have our API behind a load balancer that can scale. But how do we deploy our front-end and back-end automatically when a release is merged to our main branch? For that we are going to leverage AWS CodeBuild and CodePipeline, but in the next blog post. Stay tuned....

Sep 11, 2023

12 mins

NestJSAWSTypeScriptNodeJS

Building a Stripe App: A Step-by-Step Guide to QR Code Generation

Building a Stripe App: A Step-by-Step Guide to QR Code Generation Why Build a Stripe App? I recently participated in an audio space with the Stripe team, and something they said really stuck with me: the Stripe app store is a growing area that isn't overly saturated yet. There's a lot of potential for new apps, and companies can use this opportunity to grow. I work at a company called This Dot Labs, and we've created several Stripe apps and even own one. After looking at the data, I can confirm that the Stripe team was right! Creating a QR Code Generator App For this tutorial, we'll build a QR code app that can take a URL and generate a code for it. This is a good use case to help you understand the ins and outs of Stripe's developer tools. Why QR Codes? QR codes are useful tools that have become common in e-commerce, restaurants, and other industries. While Stripe already has a QR code tool, we'll make our own to familiarize ourselves with their syntax and problem-solving approaches. Project Structure Before we dive into the implementation, let's look at the structure of our Stripe App QR Code project: * .vscode: Contains settings for Visual Studio Code * source/views: Holds the main application views * .gitignore: Specifies files to ignore in version control * stripe-app.json: Defines the Stripe app configuration * ui-extensions.d.ts: TypeScript declaration file for UI extensions * .build: this is where the built Stripe app gets placed. Step-by-Step Implementation 1\. Install Stripe Locally First, you need to install Stripe on your local machine. The documentation provides great instructions for this: * For Mac users: Use Brew to install * For Windows users: Download the package and add it to your environment variables You can find the details here in the stripe docs to install the Stripe CLI https://docs.stripe.com/stripe-cli When using Windows, you must do stripe login from Powershell, NOT from Git bash or any other tool. After the server is up, then you can continue using git bash for everything else. After stripe login, you need to enter stripe apps start. Once you do that, the server is up and running and you can go back to using git bash or any other tool. 2\. Install Dependencies We'll be using an extra package for QR code generation. Install it using npm: ` 3\. Set Up the Main Component Let's look at the home.tsx file, where we'll use Stripe's UI components: ` These components are similar to other UI libraries like Bootstrap or Tailwind CSS. 4\. Create the UI Structure Our app will have: * An input field for the URL * Validation using a regex pattern * Error handling for invalid URLs * QR code generation and display Here is the Home.tsx file that is located in the src/views folder ` * ContextView` is at the top level of the app where we see the Title and the link to the Stripe Docs that we placed in our Context View. * Box is how you use Divs. * Banners can be used to show notification errors or any other item you wish to display. * Textfields are input fields. * Everything else is pretty self-explanatory. 5\. Handle Content Security Policy One problem I personally ran into was when I tried to redirect users, the Stripe policies would block it since I did not express that I knew what it was doing. I had to go into the stripe-app.json file and mention the specific security policies. For this particular exercise, I kept these as null. This is my stripe-app.json file. ` 6\. Configure App Views As you can see here, the stripe-app.json file shows the views for each file I have. The Home.tsx file and the Invoice.tsx are also included This is our way of saying that for each view we have, show the app functionality on that page. Our stripe-app.json file will show it but also, the manifest.js file in our .build folder will also show the same. Any view that doesn't have a file will not show the application's functionality. So, if I were to go to transactions, the app would not show the same logic as the home or invoices page. By following these steps, you'll have a fully functional QR code generator app for Stripe. This is just a simple example, but the potential for Stripe apps is massive, especially for businesses serving e-commerce customers. If you need help or get stuck, don't hesitate to reach out, danny.thompson@thisdot.co. The Stripe team is also very active in answering questions, so leverage them as a resource. Happy coding!...

Dec 18, 2024

4 mins

stripe

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Cypress testing your IndexedDb contents with @this-dot/cypress-indexeddb

Our example application

Installing the plugin

Test setup

Reading from the database

Deleting from the database

Adding data to the database

Testing if our code clears the database properly

How to run the above tests

Balázs Tápai

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