What You Will Learn Today
- Code Refactoring
- Creating Modules In Python
- Send ALGO Token From Account A To account B To C.
- Check Account' Status.
As an upcoming Algorand developer, using Python a language, you will find this resource useful as you progress in your programming endeavor/career. What cannot be taken away from you is the fundamental knowledge you will gain and its right application. Before we proceed to another topic, we will need to refactor our previous codes.
lines 2 to 10in fig 1 above every time we need to connect to Algorand testnet/node to submit a transaction. How about creating a function in a module that will contain these codes so we can reuse it each time the need for connection arises?
connect.py, in which is contained a class
Connect(), inside the class there is a function named
connectToNetwork()that does the job. Only a function would do but in future, we might probably need some of the properties contained in the class.
algod.AlgodClient(algod_token, algod_address, myProject_token).
Nothing much has change so far except that we replaced the variable
in previous lessons with
returnbeing what is required to use a function in other files.
Notice that I have changed the previous file name from
pythonTutorial.py so you don't get confused. In
pythonTutorial.py, we imported the module
connect and from it, we are able to access ``connectToNetwork() function. So far so good, the behavior of our program has not changed but for the code, therefore, refactoring can be said to have taken place.
Sending Algo Token From Account A To Account B
lines 10 to 27in fig.4. For this tutorial, we need a book to record details of the accounts generated hence the
accountsvariable of type
line 4. The function
generateAccounts()creates two wallets from
lines 12 and 13, holds each account in variables
accounts_2, then stores them in
accounts. The need for the global variable
accountsis to enable us access it easily from other files/modules.
sendTransaction.pyfile - fig.5.
line 1, we imported modules
encodingfrom algorand SDK,
Connectfrom self-created module
Set a default account from which we will initiate a transfer to
account_1, from there to
account_2, and its private key
private_key_alcto approve Algo transfer.
Lines 8 to 12 for use in
line 15allowing the network to suggest transaction parameters. Check resources for more information on transaction fields.
Activate network connection -
txnis a type dictionary encompassing suggested parameters will be returned by the network including ones we defined ==> (
notefields). We will get the defined parameters as at when the function is called - a simple hack for auto-dual transfer between 3 accounts.
trxnprepares and encode the required transaction data. Notice trxn is preceded by double asterisks? In Python, it is a way of taking in arbitrary arguments or object with several properties. It is usually represented in parameter as
signTrxnsigns the transaction with account's private key. Remember, we are expecting
trxn_idgets transaction ID.
tryblock, we provide for error that may be encountered while sending transaction.
headers is essential if you are using a third party API service such as Purestake.
In Fig.5, we execute all other files/modules.
prints the result to the consoleand
prints an empty line.
16prints account information of default account from which we will initiate the first transfer.
19gets address of generated account_1, stores it in
20gets address of generated account_2, stores it in
21stores private key of account_1 since we will send token to account_2.
sendTransaction()initiating the first transfer, and we parsed into it expected arguments -
amount. Next, print the result.
Line 26saves us the time for writing code for waiting for confirmation before we send the second transaction in
line 30. On Algorand, block finality are swift standing between 4 to 8 seconds. We need time to wait for the first transaction to confirm before initiating another transfer from
time.sleep(60). Notice we import time module on the top of the file -
line 4. Argument
sleep()function is inn seconds so we would have enough time for the first transaction to confirm before the next transaction is executed
35prints current status of all accounts in this context. Below you can read from the output.