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This blog will give a quick overview of setting development environment for Headless Development with ASP.Net Rendering SDK using the Helix Examples and the docker.
Although there are videos and blogs around same I will do a quick walk through on setting Helix Examples and any errors I faced whilst setting up the environment.
Refer the following for same – https://github.com/Sitecore/Helix.Examples/tree/master/examples/helix-basic-aspnetcore
Install .Net core 3.1 on your machine and this is required to create any rendering or platform projects later to extend the Helix Examples Solution or compiling the existing code.
Whilst installing Visual Studio 2022 select the .Net Framework project and templates option as the platform projects uses .Net Framework 4.8 version. This will also help further if you want to extend the solution.
At time when the Ganache tool is re-opened all the Transactions and Constracts are reset. Whilst deploying contract you might see the error –
ContractNotFound: No contract deployed at{address}
PS C:\Projects\Blockchain\Solidity\brownie_fundme> brownie run .\scripts\deploy.py --network ganache-local
INFO: Could not find files for the given pattern(s).
Brownie v1.19.0 - Python development framework for Ethereum
BrownieFundmeProject is the active project.
File "C:\Users\sandeep\.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\_cli\__main__.py", line 64, in main
importlib.import_module(f"brownie._cli.{cmd}").main()
File "C:\Users\sandeep\.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\_cli\run.py", line 45, in main
network.connect(CONFIG.argv["network"])
File "C:\Users\sandeep\.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\main.py", line 55, in connect
p._load_deployments()
File "C:\Users\sandeep\.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\project\main.py", line 370, in _load_deployments
contract = ProjectContract(self, build, build_json.stem)
File "C:\Users\sandeep\.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\contract.py", line 1305, in __init__
_DeployedContractBase.__init__(self, address, owner, tx)
File "C:\Users\sandeep\.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\contract.py", line 708, in __init__
raise ContractNotFound(f"No contract deployed at {address}")
ContractNotFound: No contract deployed at 0x7465E5ca8aFeFba39eFD83bd056ACAafa3d16646
Solution-
Delete all the files and folders in Deployment folder as closing the Ganache tool will reset contracts etc. the deployment folder has references to old contract.
Ganache is the development tool used to run local blockchain for Ethereum development.
Ganache can be used to deploy the contract to local Blockchain. Its a simutated environemnt like Javascript VM when developing on Remix. It helps spin up a local Blockchain.
Decentralised – Having no single point of authority
Transperancy and Flexibility
Speed and Effeciency
Security and Immutability
Removal of counterparty risk
Trust minimised agreements
Hybrid smart conrtract with Chain Link (Oracle)
Terms and Abbrevations used in Blockchain-
DAO’s – Decentralised Autonomous Organization’s
Testnet – are free and for testing smart contracts
Mainnet – cost money and are considered “live”
Faucet – is and application that gives us free test token, like free test Rinkeby Ethereum
Block Explorer – an application that allows us to “view” transactions that happen on a blockchain.
Gas – is a unit of computational measure. The more computation a transaction uses the more “gas” you have to pay for.
Every transaction that happens on-chain pays a “gas fee” to node operators.
The amount of “gas” used and how much you pay depends on how “computationally expensive” your transaction is.
Sending ETH to 1 address would be “cheaper” than sending ETH to 1,000 addresses.
Gwei (giga-wei) – denomination or a small unit of Ether 1 Ether is 1 billion Gwei. It is used to measure cost of transaction i.e. used in the Ethereum network to but and sell goods and services.
Gas – Measure of computation use
Gas Price – How much it costs per unit of gas.
Gas Limit – Max amount of gas in a transaction
Transaction Fee – Gas used X Gas Price i.e. 21,000 gas @ 1GWEI per gas =21,000 GWEI
Gas Price of Ehtereum fluctuates based on the demand of the blockchain. More perople using or want to make transactions, the higher the gas price and therefore the higher the transaction fees.
Gnesis Block – First block in a blockchain
Hash – Unique fixed length string to identify a piece of data
Hash Algorithm – A function or algorithm that computes data into a unique hash.
Mining – The precess of finding the “solution” to the blockchain “problem”. Node get paid for mining blocks.
Block – A list of transactions mined together
Nonce – A “number used once” to find the “solution” to the blockchain problem. It’s also used to define the transaction number for an account/address.
Public Key – Is derived from your private key. Anyone can “see” it, and user it, and user it to verify that a transaction came from you.
Private key – Only know to the keyholder, its used to “sign” transactions.
Elliptic Curve Digital Signature Algorithm (ECDSA) – generates public key using private key.
Signing Transactions – A “one way” process. Someone with a private key signs a transaction by their private key being hashed with their transaction data. Anyone can then verify this new transaction hash with your public key.
Node: Single instance in a decentralized network. Anyone can join the network. Blockchains are resilient. Blockchain nodes keep lists of the transactions that occur. They are immutable- nothing can corrupt them.
—Consensus – is the mechanism used to agree on the state of a blockchain.
Broken into 2 :-
— Chain Selection –
— Sybil Resistance – Proof of work. Block Author, defends on fake blockchains
— — PoW – Minners. Uses lot of electricity and is hence costly.
-Transaction Fees and Block Reward.- compete each other to find the answer to the problems. Whoever finds first get the transaction fees.
Sybil Attack – creates fake accounts to influence the network
51% attack –
Longest Chain Rule
– — PoS — Validators – nodes put up collateral as a sybil resistance mechanism. Uses less energy. Slightly less decentralised.
ABI– ApplicationBinary Interface- tells Solidity how it can interact with another contract. What functions can be called from the contract. Interfaces compile down to ABI.
Class Methods are like Class Varaibles which works on Class but not on object level.
So this methods are bound to class and not object. See class varaibles here
Clas Methods are decorated with @classmethod attribute to the method in class.
This method can be called without creating instance of the class.
See below example definition and usage of class method.
In the above example get_instance_counter() method is decorated as @classmethod and a cls variable is passed. This holdsthe class reference for which the method is called.
The constructor works normal with __init__ method and updates calss variable counter increments the counter when an instance is created. This class variable accessed in the get_instance_counter() method.
You can also provision Python class to have multiple constructor with class method. See here – How to add multiple constructor to Python class?
Create a seperate image for each application. Containers can talk to each other and can form a single large application and helps to scale each application
Don’t sotre data in Images
Images are read-only layer. When a container or image is deleted the data is lost
Use Cache Busting strategy
Install the repositories and packages together. As the docker file ises layered architecture having a seperate command for updating repositories and packages may not gurantee the repsoitories will be upto date and may result in dependency issue.
Use Version Pinning
When installing packages specifiy which version you want to install as everytime the image is build it will install the latest package where a application may not be compatible. Version pinning will always ensure the image will have specific version which your application supports.
Create slim images
This will help pull the images from which ever repository you are using quickly
Install only necessary or required packages
This will make image slim or with minimal packages and no unwanted packages are installed so every time image is build with minimal packages the build is fast and light weight. Also the containers created from such images are light weight and fast.
Maintain different images for different environements
Development images may contain debug tools and temprorary files required for debugging and bulding your application. However there tools are not required for production images. Hence remvoe any temporary files/folder and such tools for prodcution by creating a seperate image for different environments.
Use multi-stage builds to create images
Multi-stage build helps to or uses multiple FROM statements where each FROM instruction can use a different base, and each of them begins with new stage of the build and everything that is required for application is in the final image leaving behind unwanted files. This will avoid executing any script that was done traditionaly.
Exclude any unwanted files and folders using .dockerignore file
Use .dockerignore to exlcude any unwanted files and folders e.g.:- temp folder etc. this make the image lighter.
Use CMD instructions to run software in Image
Use CMD instructions to run the software contained in your image along with arguments. CMD should be used in JSON format that is the command and parameters should be seperated by comma.
Minimize build times
By avoiding to send unwanted files to the build context using .dockerengine
3. Search Category with newly created extended property i.e. DisplayType
First search all categories with Catalog Id “0001”. Following results will be shown-
Now lets try and search with extended properties i.e. Catalog Id “0001” and DisplayType as Text. For this use “Add Filter” option and key as “xp.DisplayType” and Filter Value as “Text”.
This request wont show any results and hence Xp Indices needs to created for Category
4. Create XP Indices
Navigate to Seller => Xp Indices
Indexable resources Catagory “Add Index” => “xp.DisplayType” and Save Changes
Now search the Catagories same as in Step 3 with Filter option and this time you should be able to see the results-
