TulipeContract safety
In cases ...
- your DApp is not initialized yet
- or if it is neither connected to any wallet nor to any network
- or if the connected wallet or network is not in the ones you've configured
... using the dapp.contracts.<contractName> instance is considered unsafe since it is simply unavailable or can lead to errors and/or unexpected behaviors.
So Tulipe provides developers with many safers that allows you to easily write safe code when your are using a dapp.contracts.<contractName> object, here are them.
In scripts
Read
To make a piece of code that is safe when using a read method of a contract (a method that doesn't mutate any on-chain data), you can use the onReadSafe() method of the dapp.contracts.<contractName> object :
js
import { dapp } from "tulipe";
dapp.contracts.MyContract.onReadSafe(() => {
// Code here will be executed only when the dapp.contracts.MyContract is safe to read.
})
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And if at some point in your code you have to test if the dapp.contracts.<contractName> object is safe to be read, you can use the isReadSafe computed property of the dapp.contracts.<contractName> object :
js
import { dapp } from "tulipe";
if (dapp.contracts.MyContract.isReadSafe.value) {
console.log("The DApp contract is read safe !")
}
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Write
To make a piece of code that is safe when using a write method of a contract (a method that doesn't mutate any on-chain data), you can use the onWriteSafe() method of the dapp.contracts.<contractName> object :
js
import { dapp } from "tulipe";
dapp.contracts.MyContract.onWriteSafe(() => {
// Code here will be executed only when the dapp.contracts.MyContract is safe to write.
})
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And if at some point in your code you have to test if the dapp.contracts.<contractName> object is safe to be write, you can use the isWriteSafe computed property of the dapp.contracts.<contractName> object :
js
import { dapp } from "tulipe";
if (dapp.contracts.MyContract.isWriteSafe.value) {
console.log("The DApp contract is write safe !")
}
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In templates
Read
To make a part of a template safe when using a read method of dapp.contracts.<contractName>, you can wrap it in the OnReadSafe component of the dapp.contracts.<contractName> object :
html
<template>
<dapp.contracts.MyContract.OnReadSafe>
<p>If I'm rendered is that the DApp contract is safe to read</p>
</dapp.contracts.MyContract.OnReadSafe>
</template>
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And if you want to define a content to render when the DApp contract is unsafe to be read and a content to render when the DApp contract is safe to be read you can use the #safe and #unsafe slots of the component :
html
<template>
<dapp.contracts.MyContract.OnReadSafe>
<template #safe>
<p>If I'm rendered is that the DApp contract is safe to read</p>
</template>
<template #unsafe>
<p>If I'm rendered is that the DApp contract is NOT safe to read</p>
</template>
</dapp.contracts.MyContract.OnReadSafe>
</template>
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Write
To make a part of a template safe when using a write method of dapp.contracts.<contractName>, you can wrap it in the OnWriteSafe component of the dapp.contracts.<contractName> object :
html
<template>
<dapp.contracts.MyContract.OnWriteSafe>
<p>If I'm rendered is that the DApp contract is safe to write</p>
</dapp.contracts.MyContract.OnWriteSafe>
</template>
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And if you want to define a content to render when the DApp contract is unsafe to be write and a content to render when the DApp contract is safe to be write you can use the #safe and #unsafe slots of the component :
html
<template>
<dapp.contracts.MyContract.OnWriteSafe>
<template #safe>
<p>If I'm rendered is that the DApp contract is safe to write</p>
</template>
<template #unsafe>
<p>If I'm rendered is that the DApp contract is NOT safe to write</p>
</template>
</dapp.contracts.MyContract.OnWriteSafe>
</template>
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