Upgradeable Smart Contracts: Immutable to Mutable

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Solidity - Upgradeable Smart Contracts
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Smart Contracts - Are They Really Smart?

• Smart contracts govern the way in which a
  blockchain function.
• The immutability of the blockchain extends into
  smart contracts as well - a smart contract once
  coded cannot be modified.
• This is one of the primary reasons for the
  blockchain and the data in the blockchain being
  super-secure. 
• There is no way to edit the data on the
  blockchain, and there is no way to circumvent the
  conditions laid out on the smart contract.

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Smart Contracts - Are They Really Smart?

• This advantage has made blockchain highly
  dependable for financial transactions, maximizing
  security and minimizing efforts and expenses,
  both in time and money. 
• However, sometimes, the biggest boon also becomes
  the biggest bane. Any software is supposed to
  have some room to evolve and smart contracts,
  by virtue of their immutability, lack that
  attribute. 
• Anything that doesnt change according to the
  changing times cannot be honored with the prefix
  smart, and smart contracts should not be an
  exception.

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Upgradable Smart Contracts

• Sometimes, to stay relevant, it might be
  essential to lose a quality that made you
  relevant in the first place.
• In the case of smart contracts, the solution
  lies in using upgradable smart contracts. This
  type of smart contracts solves many crucial
  problems.
• Before we proceed to discuss this revolution, we
  will need to understand the areas where
  upgradation of smart contracts in Solidity might
  be expensive and the ways to optimize the costs
  and resources.

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The Processing Cost - Block Gas Limit

• The transactions involving upgradation of smart
  contracts are relatively large, owing to the
  amount of processing that needs to be done. The
  steps include the deploying of smart contract,
  movement of data and the references.

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Inter-Contract Dependencies

• In most cases, when a smart contract is compiled,
  all the imports are originally compiled into the
  smart contract.
• This would mean that a small change in one of the
  contracts might trickle down to the other
  contracts that might reference one particular
  smart contract that is awaiting an upgrade.
• Upgradable smart contracts surely present a big
  bliss. However, the points that have been quoted
  above will have to be taken into consideration.
• These dependencies affect the size of the
  transacton. We have given below, the workarounds
  to minimize the cost and not suffer any lapse in
  the safety and security offered by Solidity.

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Avoid Copying of Large Data

• One of the most expensive parts of a smart
  contract is in storing of data. Upgradation of
  the smart contract containing large storage
  variables might have a chance of hitting the
  transaction gas limit during the data-copying
  process. 
• Therefore it is suggested that you isolate the
  data store from the rest of your code and make it
  as flexible as possible so that this hassle might
  not be always necessary.

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Avoid Copying of Large Data

• Depending on the circumstances, the size of the
  datastore you need, and the frequency of expected
  structural changes, you might want to choose a
  strict definition or a loosely typed flat store.
• The second type ensures that the data schema
  changes can be implemented any upgrades to the
  smart contract.
• If there needs to be a smart contract upgrade,
  switching the upgraded smart contract to eternal
  storage smart contract instance ensures that you
  dont have to copy any data and waste your gas on
  those operations.

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Using Libraries to Encapsulate Logic

• Libraries are special forms of contracts that do
  not allow any storage variables and exist as
  singletons.
• These libraries present a great advantage when it
  comes to smart contract upgrades - they allow
  encapsulation of business logic or date
  management logic.
• This would mean that the frequency changing
  elements of a smart contract can be coded in a
  library as opposed to the actual smart contract.
• While it might seem that every call has a gas
  overhead, the benefit of avoiding upgradation
  weighs over the expense of frequent calls. There
  have been instances where the usage of libraries
  costed 10 less.

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Using Interfaces to Decouple Inter-Contract
Communication

• In this method, abstraction of contract
  implementation happens behind and interface that
  only defines its function signatures.
• This method is quite similar to the concept of
  abstraction in object-oriented programming.
  Instead of importing the entire contract, an
  interface containing the function signatures is
  used.
• Any possible upgrades to the smart contract that
  dont affect the interface are eased. This model
  can be implemented without redeploying the
  calling contract.

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Conclusion
IMMUTABLE

• It is to be understood that, while on paper, the
  smart contract code is immutable, there is always
  a possible workaround.
• The immutable smart contract can be made
  mutable by default by having chunks of codes in
  different contracts, and the address of a
  contract can be called for execution.
• The domino-effect of an upgraded smart contract,
  in effect, renders any smart contract modifiable.

MUTABLE
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Blockchain App Factorys Upgradable Smart
Contract Services

• Blockchain App Factory, in addition to its smart
  contract development and smart contract audit
  services, also brings you enhancement of smart
  contracts on Solidity.
• Get in touch with our expert team to take your
  Solidity upgradable smart contract development
  forward to its business-relevance!!

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Touch with Blockchain App Factory

• Mail info_at_blockchainappfactory.com
• Web https//www.blockchainappfactory.com/smart-co
  ntract-development
• Mobile [phone]