Questions tagged [smartpy]
Discussion about the SmartPy language
122
questions
0
votes
2answers
58 views
How can I do string interpolation on smartpy?
I'm trying to provide better error messages. I've tried several things already that don't work such as regular python fstrings, regular string concatenation. I'm tried to using the sp.string function ...
2
votes
1answer
270 views
How to store and load custom FA2 NFT metadata?
First time I'm writing a smart contract. If anything doesn't make sense at all, feel free to call out what specifically doesn't make sense and suggest a better approach. Thanks!
At a high level I just ...
1
vote
2answers
158 views
Best Language to Use with Tezos
There are a lot of options when it comes to coding Smart Contracts on Tezos. My question is simple, which of the supported languages is the best in terms of support, east of use, documentation, and ...
0
votes
1answer
34 views
import_script_from_url syntax
i'd like to ask if it's possible to load another smart contract from an IPFS Hash or from a SmartPy url. What would be the best way to handle them with urls?
Contract A: https://smartpy.io/ide?cid=...
0
votes
1answer
82 views
Smartpy transfer contract balance to an address
I'm trying to figure out how to withdraw money from the contract within a smartpy entrypoint, and test the result in my scenario.
When I test the entrypoint:
@sp.entry_point
def withdraw(self, ...
0
votes
1answer
20 views
Is SmartPy package inside All Michaelson Supported Languages?
I've discovered that Liquidity, LigoLang and Ocamel Support Tezos development, but I've only found 1 resource that states that SmartPy supports only LigoLang. I wanted to use the right language to ...
-1
votes
1answer
58 views
Tezos SmartPy Developer Course video 1.2
How do I get find the Tezos test net as opposed to the web browser smart py interface?
Regards
WF
1
vote
1answer
34 views
How to compare a mutez value with int in smartpy
When trying to check the transferred value is positive I get an error that TMutez is not TIntOrNat.:
sp.verify(sp.amount > 0, "Amount should be positive")
1
vote
1answer
118 views
SmartPy Contract: Receive a balance?
I'm learning SmartPy and I'm trying to make a simple escrow contract. I read that contract.balance can be used to access the balance of a contract. In that case, how would I go about receiving XTZ to ...
1
vote
1answer
45 views
How to resolve sp.TKey is not sp.TAddress error in SmartPy?
I have a function like this
@sp.entry_point
def _verifySigPersonalSign(self,req,sig):
sp.verify((req.deadline != sp.timestamp(0)) | (sp.now<=req.deadline), "request ...
1
vote
1answer
36 views
How to compare timestamps in tezos smartpy?
req passed to _verifySigPersonalSign will be of type ERC
import smartpy as sp
ERC = sp.TRecord(sender=sp.TAddress,to=sp.TAddress,deadline=sp.TTimestamp)
class StoreValue(sp.Contract):
@sp....
2
votes
1answer
46 views
What is the correct usage of sp.unpack()?
*Note that the answer to this question may be very similar to this one.
I tried out the code below within a part of a larger lambda function and got the following error. The purpose is just to convert ...
2
votes
2answers
51 views
How can I avoid sp.TOption type when using sp.unpack()?
Within my smartpy contract, I want to convert from one type into another using sp.pack() and sp.unpack.
Below is an example of the method I am trying to use, converting a string to bytes.
...
1
vote
1answer
58 views
Can a Dapp buy or sell (usdtz or tzbtc) from dexter?
Looking for a way for a dapp to buy tzBTC automatically after receiving tez from a baker.
1
vote
2answers
137 views
Implementing Contract Metadata (tzip-16) on an already originated FA1.2 Smart Contract
Referring to the documents and examples of tzip-16, how would one implement the contract metadata on a Fa1.2 contract on SmartPy? In order to provide balance updates and offchain events.
1
vote
1answer
49 views
What's the best way to convert from TMutez to TBytes?
Previously when I asked about converting types, I got this useful suggestion:
For mutez, you could start to convert to int (by dividing by 1 mutez) and then use the same techniques.
I'm wondering if ...
1
vote
2answers
74 views
How to Integrating SmartPy compiler within the browser?
I have been trying to integrate the SmartPy compiler toolchain within Cryptoverse wars Learning interface and have been going through this video (OCaml Under The Hood: SmartPy) and have encountered ...
1
vote
1answer
46 views
In a SmartPy smart contract, is there 'continue' or 'break' for loop?
In a SmartPy smart contract, is there 'continue' or 'break' for loop?
When I use 'continue' for loop, an error occurred. 'Error: invalid syntax'
1
vote
1answer
57 views
How do you set the time of a transfer when testing contracts with SmartPy?
Previously, to set the (virtual) time a transaction happened in SmartPy I used the flag now when running a command like run. Now it seems to cause an error (seems like something changed in an update). ...
1
vote
1answer
70 views
How to create a contract which would delegate XTZs and receive rewards?
I am trying to write a contract that receives rewards from the baker using a default entry point and should only allow me to change the baker from a different entry point.
I am using the smartpy tool ...
1
vote
1answer
25 views
How can I manually create an on chain contract call?
Using tezos sandbox mode, I am trying to test an on chain contract call in isolation of the main contract which calls it. If my contract was the Collatz template, it would like be trying to run the ...
2
votes
1answer
80 views
1
vote
1answer
32 views
How should sp.if be used?
I find I run into some unexpected behavior when using sp.if. e.g.
a = False
sp.if 1 > 2:
a = True
seems to result in a == True.
The example below is doing so in the ...
1
vote
1answer
22 views
SmartPy: How to test an invalid transaction sent from a contract call
I am testing a contract in SmartPy that uses a contract call (similar to the Collatz example).
Contract 'A' sends a transaction to contract 'B' with some data.
Contract 'B' does some computation and ...
1
vote
2answers
100 views
How can I write On Chain Contract Calls in Tezos Sandbox?
I am trying to write a test case in Tezos Sandbox that uses an On Chain Contract Call. To start with, I am trying to implement the example from SmartPy "On Chain Contract Calls - Collatz" ...
1
vote
1answer
31 views
in smartpy, local variable param, what's difference?
in smartpy
def aa(self) {
value_in_func = "1234"
msg = "abc" + value_in_func
hex_string = msg.encode("utf-8")
thingToSign = sp.bytes("0x" + ...
2
votes
0answers
67 views
how to hook function in smartpy FA2
when calling transfer method, how to call hook method on received smart contract.
I'm using fa2 in smartpy
1
vote
1answer
22 views
How does sp.record arrange data into pairs?
For example if I have the following code:
sp.record(one = one, two = two, three = three, four = four, five = five)
Would the format of the result be
pair(one pair(two pair(three pair(four five))))
or
...
1
vote
1answer
37 views
Can we have a Time clocked transaction in Tezos?
I want to make an escrow contract where the transaction can be done after an interval. Is it possible / any hack that can make it happen?
The balance should get deducted from the sender beforehand and ...
1
vote
1answer
55 views
How do you do sp.record(sp.pack()) outside of SmartPy?
I have a smart contract which verifies a signature from Bob in order to do something. The contract was made using SmartPy and for testing the scenario I used the following code to produce a signature:
...
1
vote
1answer
32 views
What guarantees do we have when verifying the sender's identity (in SmartPy)?
When we check the address that called the current entry point e.g. in SmartPy:
sp.verify(self.data.authorizedAddr == sp.sender)
What guarantees do we have? For example, is it possible for someone ...
2
votes
1answer
100 views
Why does smartpy use sp.for/sp.while instead of the default loops provided by python?
So I just started out with smartpy and I am kinda confused about the point of having separate expression for loops. My understanding is that it is may be because it's a part of on-chain computations, ...
3
votes
4answers
117 views
Is it possible to use natural logarithmic in your smartpy code?
If not,is there any alternative way to implement a natural log component into your smart contract code?
4
votes
1answer
113 views
Calling view of Fa1.2 contract
From my understanding, getBalance, getAllowance, getTotalSupply & getAdministrator entrypoint requires another contract to read the values. How will the entry point of the second contract look ...
2
votes
4answers
128 views
Is there a formula to build parameter messages to be passed to smart contract entrypoints?
When calling a smart contract entrypoint, it is required to pass the needed entrypoint parameters. This is done through a message that must be sent in JSON/Pairs format. My doubt is: Is there a ...
2
votes
1answer
131 views
How to get a contract storage data from another contract in smartPy?
I'm trying to access a storage data of a contract from another one using the continuous passing style in smartPy.
import smartpy as sp
class XXIFA12(sp.Contract):
def __init__(self, admin):
...
1
vote
2answers
121 views
How to get a contract storage data or call a "get" entrypoint from another contract in smartPy?
I want to interact with the FA12.py smart contract (https://smartpy.io/demo/index.html?template=FA1.2.py) and get the balance of a user, from another smart contract.
the FA12 function that I tried to ...
3
votes
3answers
126 views
How to delegate the balance of a smart contract?
I am looking to create a smart contact that will delegate the funds it is storing.
1) How does an originated KT address delegate to a baker?
2) If a KT address delegates, can it do anything else?
I ...
1
vote
1answer
88 views
Trouble with calling a function with parameters with Taquito
I'm trying to use taquito to call a method in my contract. Note my contract was programmed in SmartPy (if that makes any difference).
I am able to call contract.storage() without any problem.
When ...
1
vote
2answers
100 views
Send tezos to contract address after origination using conseiljs
I am trying to send tez from my tz1-AAA account to KT1-AAA contract address means I want my contract address to hold some tez.
Disclaimer - I have knowingly replaced some part of address with "....(s)...
2
votes
0answers
56 views
how can i call specific smartpy tezos contract entrypoint using ConseilJs?
I am trying to set UI that allow users to interact with tezos smart contract by pressing some buttons that have to call the corresponding function in the smart contract with relative arguments
1
vote
1answer
30 views
set a ui to allow to nodes interact via smartpy contract
Hii have wrote a smart contract using smartpy where i have two nodes that should interact with each other, now i want to set the user interface to simulate the nodes interact what should i use and ...
-1
votes
1answer
56 views
Encryption in smartpy tezos
I wanted to give encryption to a string before storing it in smart contract.
For example I have "hello" its 256 equivalent should be "2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824"
...
2
votes
1answer
60 views
Cyclic inter contract calling in smartpy
What I am trying to achieve is that, once I receive data from another contract my contract should return data after computation to same contract who has sent the data.
Computational Contract
import ...
5
votes
1answer
47 views
bigmap.get(key, "") with default param in case of no entry for key in the map with Taquito
Can we do something similar to myMap.get(key, defaultValue = None) of smartPy with Taquito?
An instruction like:
const myContract = await Tezos.contract.at(contractAddress);
const contractStorage = ...
1
vote
1answer
86 views
sending data from one contract to another smartpy tezos
I am trying to send data from one contract to another in smartpy
Remote Contract
import smartpy as sp
class Try(sp.Contract):
def __init__(self):
self.init(mynum = sp.int(0))
@sp....
1
vote
2answers
127 views
Taquito default entrypoint not found
I have deployed a smart contract on carthagenet.
The contract only has a single entry point.
Taquito is not able to find that single entry point. I tried both default and root methods and it doesn'...
1
vote
1answer
28 views
Get current ChainId in smartPy contract
I'm trying to get the chain_id of the current chain evaluating a transaction or containing the smart contract with smartPy, but I got always error in init and in entrypoints when I try to affect the ...
2
votes
1answer
106 views
How do we use getBalance() function in FA1.2 token contract in SmartPy?
https://smartpy.io/demo/index.html?template=FA1.2.py&source=post_page---------------------------
This is the token contract link.
It is deployed on the https://babylonnet.SmartPy.io node with the ...
0
votes
2answers
130 views
how to transfer tezos to contract
I deployed a contract at babylonnet, source code is https://smartpy.io/demo/index.html?code=eJzVV22L3DYQ_r6_Qvg@xOaM2beQcODSvJAmDRtKbkkox2F0tnatnld2JTl7m5L89owkv0j2ZrMf2tIaDuzRaPTMM8@...
