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.
Code Refactoring
lines 2 to 10
in 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
algod_client
in previous lessons with
return
being what is required to use a function in other files.
Notice that I have changed the previous file name from day_4.py
file to 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 27
in fig.4. For this tutorial, we need a book to record details of the accounts generated hence the accounts
variable of type dictionary
- line 4
. The function generateAccounts()
creates two wallets from lines 12 and 13
, holds each account in variables account_1
and accounts_2
, then stores them in accounts
. The need for the global variable accounts
is to enable us access it easily from other files/modules.sendTransaction.py
file - fig.5.From
line 1
, we imported modulesalgod
,transaction
,encoding
from algorand SDK,Connect
from self-created moduleconnect.py
file andaccounts
fromgenerateaccounts
file.Set a default account from which we will initiate a transfer to
account_1
, from there toaccount_2
, and its private keyprivate_key_alc
to approve Algo transfer.Lines 8 to 12 for use in
line 15
allowing the network to suggest transaction parameters. Check resources for more information on transaction fields.Activate network connection -
line 14
.Inside
sendTransaction()
function,txn
is a type dictionary encompassing suggested parameters will be returned by the network including ones we defined ==> (my_address
,receiver
,amount
andnote
fields). We will get the defined parameters as at when the function is called - a simple hack for auto-dual transfer between 3 accounts.trxn
prepares 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**kwargs
.signTrxn
signs the transaction with account's private key. Remember, we are expectingprivatekey
as input.trxn_id
gets transaction ID.In the
try
block, we provide for error that may be encountered while sending transaction.
Note: Argument headers
is essential if you are using a third party API service such as Purestake.
In Fig.5, we execute all other files/modules.
Lines 11
,12
and13
callsgenerateAccounts()
function,prints the result to the console
andprints an empty line.
16
prints account information of default account from which we will initiate the first transfer.19
gets address of generated account_1, stores it inalc_2_addr
.20
gets address of generated account_2, stores it inalc_2_addr
.21
stores private key of account_1 since we will send token to account_2.trxn_1
callssendTransaction()
initiating the first transfer, and we parsed into it expected arguments -privateKey
,sender
,receiver
andamount
. Next, print the result.Line 26
saves us the time for writing code for waiting for confirmation before we send the second transaction inline 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 fromaccount_1
hencetime.sleep(60)
. Notice we import time module on the top of the file -line 4
. Argument60
passed intosleep()
function is inn seconds so we would have enough time for the first transaction to confirm before the next transaction is executed33
,34
and35
prints current status of all accounts in this context. Below you can read from the output.