Hello guys, here are the slides from the workshop on Blockchain Tests that I gave earlier this week, as well as some responses to the issues that were addressed during the session. I can say as my first presential workshop after pandemic, it was a great experience with a full room 😃
Unfortunately, there is no recording of it, but you may clone the repo and follow the coding instructions to build the test class and methods, then compare to version 2 of the project, which has the most recent version.
The require Solidity function guarantees validity of conditions that cannot be detected before execution. It checks inputs, contract state variables and return values from calls to external contracts.
The address type comes in two flavours, which are largely identical:
address: Holds a 20 byte value (size of an Ethereum address).
address payable: Same as address, but with the additional members transfer and send.
The idea behind this distinction is that address payable is an address you can send Ether to, while a plain address cannot be sent Ether.
Type conversions
Implicit conversions from address payable to address are allowed, whereas conversions from address to address payable must be explicit via payable(<address>).
Explicit conversions to and from address are allowed for uint160, integer literals, bytes20 and contract types.
Other tools that you can use to test Blockchain applications
Today I am going to post a quick snippet that I used recently and it quite made me spent a lot of time just because I didn’t read the Jmeter documentation in the first place 😅
In the pom.xml you will need to set some jmeter configurations:
Now you can run your jmeter tests passing a json code to the maven command line and if you don’t pass this parameter, then Jmeter is going to use the default one.
Hello guys !! After my talk about Testing Blockchain Applications on the #TechKnowDay, I thought it was worth posting a guide on the same topic as I felt it was complex to also understand Blockchain. So, this is a quick tutorial on how to run tests with Truffle Framework.
If you are still wondering where you can use Blockchain, here it’s a table with the percentage of companies that are focusing on it and the use cases.
We are going to use a bit of Javascript for the web part and Solidity for the blockchain project. For this project you will need to have installed NPM and Node already. We are going to install Truffle as part of the setup. You will also need MetaMask and Ganache, all of them you can find bellow:
Open your MetaMask plugin and click on new Custom RPC Network. Type the following (Currency Symbol will be automatically populated after you type the Chain ID) and save.
Open Ganache, click on Quick Start (Ethereum). Double check if the server has this configuration clicking on the on top right and then Server tab.
Click on Show keys of the account you have created and copy the private key.
Back on MetaMask, click on Import Account and add the private key you have copied from the previous step.
Setting up the project
On your terminal run:
npm install -g truffle
If you want to follow the test steps only, then you need to download the first release that contains the installation files of the project already:
If you want to try the installation for yourself from the scratch, then just go to this link and follow the Getting Started guide. This guide won’t be focusing on the installation of the framework or the setup of the contracts and migrations.
Just a heads up that for this project I am using the pet-shop box instead of the MetaCoin from the Getting Started guide.
Installation
After downloading the project, you will need to run some commands to set it up. Open your terminal on the root of the project and run:
Run the development console
truffle develop
Compile and migrate the smart contracts. Inside the development console you don’t need to type the truffle command.
compile
migrate
To get out of the truffle console type
.exit
Create a new file inside of the test folder called TestAdoption.sol and import all the needed modules, such as assertions, new instances of deployed addresses and the contract that will be tested.
Add the testUserCanAdoptPet() function below the variables block.
Note that here you are creating a function that will test you can adopt a pet and for this you will need to get the address related to the adoption transaction and compare the returnedId with the expectedPetId address
Try to explore and add other asserts like checking if it’s not returning null.
function testUserCanAdoptPet() public {
uint256 returnedId = adoption.adopt(expectedPetId);
Assert.equal(
returnedId,
expectedPetId,
"Adoption of the expected pet should match what is returned."
);
}
Asserting the adopter of the pet
Add the testGetAdopterAddressByPetId() function below the previous function.
This function will check if the adopter address for that pet is the same from the adopters list
Try to explore and add other asserts like comparing the age of the pet is returning correctly, for that you would need to add the age on the Adoption.sol contract, then compile and migrate again.
function testGetAdopterAddressByPetId() public {
address adopter = adoption.adopters(expectedPetId);
Assert.equal(
adopter,
expectedAdopter,
"Owner of the expected pet should be this contract"
);
}
Asserting the list of adopters
Now add the testGetAdopterAddressByPetIdInArray() function below the previous function.
This function will check if the memory address for this petId is the same as the expectedAdopter
Almost the same test as before, but this time we are explicitly storing adopters in memory rather than contract’s storage and then comparing them.
function testGetAdopterAddressByPetIdInArray() public {
address[16] memory adopters = adoption.getAdopters();
Assert.equal(
adopters[expectedPetId],
expectedAdopter,
"Owner of the expected pet should be this contract"
);
}
}
You should have something like this:
pragma solidity >=0.5.0;
// The first two imports are referring to global Truffle files, not a `truffle` directory.
// Gives us various assertions to use in our tests.
import "truffle/Assert.sol";
// When running tests, Truffle will deploy a fresh instance of the contract being tested to the blockchain.
import "truffle/DeployedAddresses.sol";
// The smart contract we want to test.
import "../contracts/Adoption.sol";
contract TestAdoption {
// The address of the adoption contract to be tested
Adoption adoption = Adoption(DeployedAddresses.Adoption());
// The id of the pet that will be used for testing
uint256 expectedPetId = 8;
//The expected owner of adopted pet is this contract
address expectedAdopter = address(this);
// Testing the adopt() function
function testUserCanAdoptPet() public {
uint256 returnedId = adoption.adopt(expectedPetId);
Assert.equal(
returnedId,
expectedPetId,
"Adoption of the expected pet should match what is returned."
);
}
// Testing retrieval of a single pet's owner
function testGetAdopterAddressByPetId() public {
address adopter = adoption.adopters(expectedPetId);
Assert.equal(
adopter,
expectedAdopter,
"Owner of the expected pet should be this contract"
);
}
// Testing retrieval of pet owner storing getAdopters in memory
function testGetAdopterAddressByPetIdInArray() public {
// Store adopters in memory rather than contract's storage
address[16] memory adopters = adoption.getAdopters();
Assert.equal(
adopters[expectedPetId],
expectedAdopter,
"Owner of the expected pet should be this contract"
);
}
}
Running the tests
Open your terminal on the root of the project and run:
truffle test
If everything went okay you will see green checks on your terminal like this:
You can check the final code with the latest release (Spoiler alert: You will see pictures of my dog, my dog’s best friend, my friend’s cat and my previous dog)
Hello all, I have been wondering what will be the trends for this year. Last year, I noticed an increase in accessibility and performance tests concerns because of the increased number of users going online due to the pandemic.
I believe this is going to continue this year and then we will definitely have an increase on the other trends that were already around for the past years. I have condensed some of these trends here:
Blockchain
Think about how the world changed after the internet, everybody is connected. Billions and billions of transactions are made per second, because of that, the concern with the security is even more important. Blockchain arrived with the idea of making it difficult or impossible to change, hack, or cheat the system. Blockchain is essentially a digital ledger of transactions and smart contract (chaincode) services to applications that is distributed across an entire network of computer systems.
This has been a hot topic in the past years, so nothing really new, but you will definitely see an increase as people are still learning and understanding what are the benefits of it and what are the problems that Blockchain solves. Once you understand you never go back.
Augmented Reality
Again nothing really new here, you can see videogames have been using this a lot and it was definitely a boom when you could catch Pokemons in the middle of the street !
With Augmented reality (AR) you can have a real-world interactive experience. The objects from the real world are enhanced by the computer-generated perceptual information, or even combined with digital created objects. You can see an increase on this trend as again people are getting more and more online and avoiding going to the stores because of the pandemic. Now you have the ability to try clothes online for example.
I have never really joined a project with Augmented Reality, but this would be another challenge since you need to keep in mind things like speed you move, lights, objects and other variants.
Chatbots and Artificial Intelligence
I know many people hate chatbots but, for someone that hates calls or just wants to make a quick question, or even just want things to be solved as fast as possible like me, this is the right option. Of course there is still a lot to improve on the machine learning side of the technology, but depending on the how you were able to train the bot, you can even think you are talking to a real person.
I am not going to deny that there is a lot of training of words and phrases until it feels like talking to a human but, some chatbots are really useful, for example if you need to return a purchase on Wish app. Today, chatbots are used most commonly in the customer service space, assuming roles traditionally performed by living, breathing human beings such as Tier-1 support operatives and customer satisfaction reps.
Artificial Intelligence (AI) is here to stay since the beginning of its creation. Big companies like Tesla, Amazon (Alexa), Apple (Siri) are more and more sophisticated. You can expect Machine Learning to be used in the automated tests more and more and also to think about the tests you will need to perform on AI projects.
Mobile Apps (Fitness, Mental Health, E-commerce, Services in general)
It is rare to find a person that doesn’t have a smartphone nowadays, even kids need to have so the parents can contact them to see if everything is okay. The pandemic brought more people to look for mental health and fitness apps than ever, is this going to stay even after our current situation ?
Mobile tests are way more full of details, things you need to consider, like the speed of the internet connection, orientation of the screen, sending the app to the background and opening again… The market is flooded with millions of apps and we have too many options now, so how will new apps find their place? Quality of the service, Usability and Price.
Usability and Accessibility Testing
This is another hot topic as the pandemic pushed more people to go for online services. Keeping accessibility tests in mind you will help people with disabilities to be able to navigate and interact with websites and tools. It also means that they can contribute equally without barriers.
Usability Tests is more about the design of the products. People don’t want to tap 300 times to be able to login or pay for a product, your app needs to be efficient, effective and satisfying. A lot of people don’t realise how this is important, but once you lose a client because of a small mistake it might be hard to get it back.
Internet Of Things (IoT)
Share data and automate services are a must have ! Nowadays you need to have the option to share your fitbit steps with your scale, for example. There is a huge demand to access, create, use and share data from any device.
The thrust is to provide greater insight and control, over various interconnected IOT devices. Which means you need to have the option to tell Alexa to turn on or off the lights when you are too tired to get out of the bed to do it.
I particularly didn’t see too much movement in this area last year, maybe because of all the other more urgent things we had to deal with, but this is another thing that is going to continue increasing, even though I can see a lot of security concerns around having everything connected. Imagine if somebody is able to hack your printer and then getting access to your front door lock ?
Data Protection and Security Tests
This is something you need to keep in mind every time you have a new feature coming up, or even updating a current feature. We need to identify the threats in the system and measure its potential vulnerabilities, so the threats can be encountered and the system does not stop functioning or can not be exploited.
Security tests were always important, but I always felt it was a bit neglected until something bad happens, then was treated as first priority. Here in Europe we need to be super careful with the GDPR rules and make sure we are not exposing personal data anywhere. So, another thing to keep in mind as if we have more people accessing the internet, it means we have more people trying to steal data as well.
Coding Skills and QAOps
Another name for the QA role, like we don’t have enough 😂 (QA, Tester, SDET, Software Developer in Test, Test Automation Engineer, Full Stack QA and the list goes on…). What is this new QAOps name ?
It is a combination of Quality Assurance (QA) and software operations. QAOps combines QA practices with software development and IT operations to develop a long-term, integrated operational delivery model.
This month I’ve completed 10 years blogging, time flies! I can’t believe that I used to blog about investments and economy as well, another subject that I love.
So here I am, after 10 years. I slowed down a lot last year, I used to post every week non-stop for so many years and last year due to to other priorities I started posting monthly. This year I still have other priorities, but will plan ahead and see what is possible.
Those other priorities included some meetups, presentations, courses and I even had to deal with my boiler exploding! So I was completely drained in the end of the year.
My plan for this year is going back to post on this blog every 2 weeks, take my British citizenship, continue with my STEM Ambassador activities, continue active on the QA community, continue exercising and eating healthy and finally play drums every week again.
Here it is what I use to help me to organise myself:
This is helping me a lot, every time I receive an email or something that I need to solve but not now, I just create an event and that’s it, I don’t need to think about remembering or checking, I receive a notification as soon it is due.
I create recurrent events for example, prep meals for the week or study X or Y, so they help me to keep going. I also send emails to myself to remember about something that I need to do as soon as possible, but for that to work you need to have a clean inbox, otherwise you will end up with loads of unfinished things.
I bought a white board to write and plan things that are a bit more complex, or just to help my mind to focus on the big picture of the next achievements. It helps when you have something to look forward to and get you excited and makes you get a bit of discipline.
The last one that is not a tool is actually an action. It changed my routine completely: Getting out of social media, not all of them of course. I am still on Twitter and Linkedin, but all of the others were just draining my time when I was bored and I found myself opening these apps out of impulse. Now I am connected with people that really matter to me.
Hey guys, this is a long due meetup post that I haven’t shared here. It was a great discussion, sharing ideas and meeting new people with different experiences. I highly recommend everyone to join a meetup like this one day or another as it is really dynamic and enjoyable.
The link to the meetup is here, but as you can see it is from the middle of the last year.
What is Quality and Who Cares About It? Roundtable Event (No Spaces Available)
Thursday, Jul 23, 2020, 5:30 PM
Online event ,
1 Advocates Went
We’ll be sharing a recording of a roundtable discussion, as we have set up a small group to discuss the meaning behind quality within organisations.
Hello all, today I am going to post about a topic that I am a huge enthusiast about: Blockchain !
Nowadays data is one of the most valuable product that you can own, and as we are surrounded by fake data coming from thousands of different places, it is hard to know what is trustworthy or not.
What is Blockchain ?
It is basically the second phase of the internet. The Internet democratized the exchange of information, blockchain promises to democratize the exchange of real value. It was created in 2008 by Satashi Nakamoto, which the identity is still unknown.
An example of how blockchain can be used is when you want to make a transaction of £10 from a X to Y. Nowadays what happens is this transaction goes through a third-party app or payment processing system. Then, X’s bank will need to check the details of Y’s bank and once this is done the transfer of the amount will initiate with a certain amount of deductions, of course. In the end both banks will record the transaction deducting the transaction fee, meaning Y will receive something like £9.95. Even though this process is quite secure and has many redundancies in place to make sure that it stays secure and accurate, there are some basic fundamental issues with this process:
Delay in processing (using this middle agent and all the bureaucracy)
Dependency on a single intermediary whose effectiveness is never 100 percent (dependency on a national state)
In case of any gap in the transaction, no one takes the responsibility and people keep on blaming each other (not concrete proof to check the transaction)
Blockchain is a system where you no longer have to worry about these problems, you just need to perform a transaction and there is a chain of people who are able to validate your transactions every second. This mechanism is called as Proof of block and this is done based on the public key provided for the encrypted data, and it is done by all listeners in the peer-to-peer network. They are real people/identities, not bots. Since there is not a single transaction validating authority (banks, national state) who are centralising the transaction service, the process is effectively decentralized, public and transparent for everybody to see.
Once a specified number of people validates the transaction, the transaction details are stored in the form of a block and that block is added to the existing blockchain. Once the blocks are validated, nobody can change them, just add another one on top, they are immutable. These blocks have a specific hash associated with every block. These hashes are like fingerprints and are unique to every block. Every person that is validating the transaction process is called a miner. The more miners, the better efficiency of the transaction.
A block containsdata, a hash, and the hash of the previous block. Since it contains a hash of a previous block, all the blocks contain data for the previous blocks and it becomes almost impossible for a blockchain to be corrupt.
What types of tests can I perform in a Blockchain app ?
API Testing: In API testing, we ensure that the interaction between applications in the blockchain ecosystem is as expected
Block/Peer/Node Testing: All the blocks on the Network should be tested individually to ensure proper cooperation. All diverse nodes on the Network must be tested independently to ensure smooth cooperation. Do the nodes in the network sync with other validating peers? Is the integrity of the network and shared ledger maintained throughout the testing?
Functional Testing: In Functional Testing, we evaluate the work of various functional parts of the Blockchain (e.g., smart contracts).
Performance Testing: Details like network latency based on block size, network size, expected transaction size, and how long a query takes to return the output with the specialized authentication protocol
Security Testing: Here, we ensure that the application is not vulnerable to attacks and the systems can protect the data and are capable of handling malicious attacks, etc.
Integration Testing: In Integration testing, we ensure that all the components of the application are integrated properly and performing the actions appropriately
Smart Contract Testing: Smart Contract testing is about performing detailed functional testing of business logic and process. It refers to the set of software constructs that automatically execute transactions when predefined conditions and business logic are met. Testing smart contracts involve simulation of all possible expected and unexpected variables for every contract and the triggers that execute transactions.
Benefits of Blockchain Apps
Decentralized System: No need to have a middle agent for the transactions. Beneficial in various industries like finance, real estate etc.
Better Security: As it uses multiple nodes to complete and authenticate transactions, you don’t rely only on a transaction system that is controlled by a centralized group of identities.
Authenticity: Allows the unique algorithm to process data, like a fingerprint.
Increased Capacity: Increases the capacity of the entire Network as it is completely decentralized and real people can verify the blockchain.
Challenges in Blockchain Testing
Understanding the Technology: Blockchain is a new technology and understanding it is very important in order to test it. Where does regulatory compliance overlap with quality? How do you fix a defect that has been deployed as part of an immutable smart contract? How do you predict transaction fees and determine the correct behaviour of your application if transaction fees and network volume increase unexpectedly?
Lack of Blockchain Testing Tools: Blockchain-based applications testing is all about tools. Selecting the right tool as per application is one of the important decisions.
Defining Test Strategy: Designing Test Strategy for Blockchain application is quite complex exactly because you need to have a good understanding and in-depth knowledge of the technology.
Block and Chain Size: Testing for block size and chain size is quite important as the application may fail without proper validation of block size and chain size and creating a false-positive verification.
Integration Testing: Should be done properly and frequently to test that all the components are properly integrated.
Performance and Load: You need to perform load testing to give better insight into how the Blockchain application performs in the real world, check if it is scalable and what are the limits. Check the example that was done to Ethereum and the Cryptokitties.
Security: Securing the data should be the most important thing in a Blockchain Application, to be honest, in any application. Even bitcoin is not bug free !
What do you need to consider when testing a Blockchain Application?
Here it goes an example with Bitcoin transaction tests:
Block Size: The maximum fixed limit of a block is 1 megabyte. After the introduction of Bitcoin, the average size of a block for the first 18 months came out to be under 30 KB. But in December 2017, it hovered around 1 MB. What if the size of a block exceeds beyond 1 MB?
Chain Size: There is no limit on the size of the chain. So, it is fun to test it for its function and performance. For example, the Bitcoin chain’s size keeps on increasing day by day.
Load: With so many people on the blockchain, the load becomes a major parameter to test in a blockchain. Bitcoin currently has a maximum throughput of 3.3 – 7 transactions per second, but what if the transaction/second increases as in the case of Visa(2000), Paypal(193), etc? The load remains a major problem with blockchain because performance drops when the load increases.
Security: Since there are many miners involved with a transaction, ensuring security is a little complex. Well, there is a multi-layered security system in a blockchain. If one of the layers has been hacked, the instantaneous transactions cannot be stopped. It is, therefore, to be tested that one security layer doesn’t affect the other.
Transmission of data: Encrypted and decrypted data is transferred from computer to computer, so it is necessary to test if the transmission process is working flawlessly. Is the data being sent received on the other end, or is there a loss in between?
Addition of block: Every new block is added to the chain once the transaction’s validity is authenticated. So, it must be tested that there should not be any leak in the block addition system and the block must be added after authentication.
Cryptographical data: Cryptography is the backbone of blockchain technology. Therefore, it is necessary to make sure that the data is properly encrypted and decrypted.
Blockchain Testing Tools
Ethereum Tester: It is an open-source testing library available as a Github repo. Its setup is pretty easy with a manageable API support for various Testing requirements.
BitcoinJ: It is a Java-based framework built for Bitcoin-based apps that enables you to interact with the real BTC network and various testing activities. In order to use it, you don’t have to download the standard BTC Core files from Bitcoin.com. You can even approach a user forum in case you need clarification or are facing hiccups in the testing process. It is an open network available for assistance.
Populus: This framework has the testing functionality of Ethereum embedded in the form of a set of features for test contract deployment. It’s developed around the py.test framework. Hence, it is relatively easy to implement.
Truffle: It’s a commonly referred name for Ethereum developers, which brings in good testing features, such as automated contract testing. The framework holds capabilities beyond just testing functionality within the Blockchain application.
Embark: It is a testing framework that focuses on developing decentralized applications (dApps) that run on various systems or nodes. It has integrations with Ethereum blockchain, IPFS, and a decentralized communication platforms such as Whisper and Orbit.
Hello all, after a small burnout and a month break from my extra work activities (2nd lockdown here in London and winter vibes definitely didn’t help), I am finally back on track and I thought it was worth sharing this CI/CD Pactworkshop that was published in the middle of this year.
They use Node, but you don’t need to be an expert to try this workshop. Once you have finished, you will be able to fit Pact and Pactflow into your CI/CD pipelines and understand the workflow when changing the consumer and provider.
I followed all the steps and after around 1h20m I finished it. It is pretty straight forward and it includes the new feature pending pact that is equivalent to the pending tests tag, just make sure you are copying the right tokens and using the right URLs.
The link to the workshop with the instructions and requirements are here:
A friend of mine has recently passed the CTFL Exam after one week of a lot of study and effort. CTFL is a popular Certified Tester Foundation Level exam in software testing. It examines your professional knowledge around software testing discipline. The exam has 40 questions and takes 60 minutes.
Should I take the exam ?
This is a very debatable subject and people can discuss for hours about it’s value.
If you are thinking about if this is for you or not, these are some things that you can keep in mind and help you to decide:
Experience always has more value than any certification. Certifications don’t provide the exposure and training you get while working on real life projects !
THIS CERTIFICATION CAN HELP YOU TO GET YOUR FIRST QA JOB. If you are changing careers, never worked with Software Testing before, then this certification might help you to be selected for an interview. This would be part of your portfolio and as you might not have any experience in this field, this can be used as a parameter when filtering the candidates.
THE CERTIFICATION DOESN’T MEAN YOU ARE AN EXPERT OR THAT YOU ARE GETTING THE JOB. Most of the professionals applied to this certification in the beginning of their career and then never study the Syllabus again. This is because you start to use your experience more than the base knowledge you got when studying for the exam. Again the certification doesn’t mean you will get the job, experience and exposure to different projects will.
One technique that I use for actually most of the exams that I apply is practicing the mock exams and once I pass 3 times in a row then it means I am mostly ready to take the real one. You might have other ways to see when you are actually ready, but whatever you follow make sure to prepare and dedicate yourself !
Ada Lovelace was an english mathematician and is recognised as “the first computer programmer” due to the creation of an algorithm for a computing machine in the mid-1800s. She was one of my first inspirations after my parents and my oldest brother to come to the Technology area.
Her childhood background also resembles mine, she had ability with math since little, focused on studying as much as possible and not having a father figure when little ! She is a truly inspiration to me and hopefully to many other women out there.
The Ada Lovelace Day was created in 2009 by Suw Charman-Anderson and it is now held every year on the second Tuesday of October. It is an international celebration of the achievements of women in science, technology, engineering and maths (STEM). The goal of this celebration is to motivate and bring more women in STEM, creating new role models and support women already working in this area.
on top right and then Server tab.
Rafaela Azevedo 