chore: refactor token examples

CHANGELOG.md

@@ -23,6 +23,7 @@ This changelog is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.
 
 ### Changed
 
+
 - Renamed `examples/nft_allowance.py` to `examples/account_allowance_nft.py` for consistency with account class naming scheme
 - Added changelog conflict resolution examples to `docs/common_issues.md`
 - Refactored `examples/topic_create.py` to be more modular by splitting functions and renaming `create_topic()` to `main()`.
@@ -33,8 +34,10 @@ This changelog is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.
 - docs: Improved the contributing section in the README.md file
 - Refactored `examples/transfer_nft.py` to be more modular by isolating transfer logic.
 - Renamed `examples/hbar_allowance.py` to `examples/account_allowance_hbar.py` for naming consistency
+- Refactored token-related example scripts (`token_delete.py`, `token_dissociate.py`, etc.) for improved readability and modularity. [#370]
 - Converted monolithic function in `token_create_nft_infinite.py` to multiple modular functions for better structure and ease.
 
+
 ### Fixed
 
 - Add type hints to `setup_client()` and `create_new_account()` functions in `examples/account_create.py` (#418)

examples/token_delete.py

@@ -1,8 +1,10 @@
-"""
-uv run examples/token_delete.py
-python examples/token_delete.py
+# uv run examples/token_delete.py
+# python examples/token_delete.py
 
 """
+A full example that creates a token and then immediately deletes it.
+"""
+
 import os
 import sys
 from dotenv import load_dotenv
@@ -19,37 +21,38 @@
 # Load environment variables from .env file
 load_dotenv()
 
-
-def create_and_delete_token():
-    """
-    A full example that creates a token and then immediately deletes it.
-    """
-    # 1. Setup Client
-    # =================================================================
+def setup_client():
+    """Setup Client """
     print("Connecting to Hedera testnet...")
     client = Client(Network(network='testnet'))
 
     # Get the operator account from the .env file
     try:
         operator_id = AccountId.from_string(os.getenv('OPERATOR_ID'))
-        # NOTE: Assumes your operator key is a raw Ed25519 key
         operator_key = PrivateKey.from_string(os.getenv('OPERATOR_KEY'))
+
     except (TypeError, ValueError):
         print("Error: Please check OPERATOR_ID and OPERATOR_KEY in your .env file.")
         sys.exit(1)
-
+    # Set the operator (payer) account for the client
     client.set_operator(operator_id, operator_key)
     print(f"Using operator account: {operator_id}")
+    return client, operator_id, operator_key
+
+def generate_admin_key():
+    """Generate a new admin key within the script:
+    This key will be used to create the token with admin privileges
+    """
 
-    # 2. Generate a new admin key within the script
-    # =================================================================
     print("\nGenerating a new admin key for the token...")
     admin_key = PrivateKey.generate_ed25519()
     print("Admin key generated successfully.")
+    return admin_key
+
+def create_new_token(client, operator_id, operator_key, admin_key):
+    """ Create the Token"""
     token_id_to_delete = None
 
-    # 3. Create the Token
-    # =================================================================
     try:
         print("\nSTEP 1: Creating a new token...")
         create_tx = (
@@ -67,14 +70,18 @@ def create_and_delete_token():
         create_receipt = create_tx.execute(client)
         token_id_to_delete = create_receipt.token_id
         print(f"✅ Success! Created token with ID: {token_id_to_delete}")
+        return token_id_to_delete
 
-    except Exception as e:
+    except (ValueError, TypeError) as e:
         print(f"❌ Error creating token: {e}")
         sys.exit(1)
 
 
-    # 4. Delete the Token
-    # =================================================================
+def delete_token(admin_key, token_id_to_delete, client, operator_key):
+    """
+    Delete the Token we just created
+    """
+
     try:
         print(f"\nSTEP 2: Deleting token {token_id_to_delete}...")
         delete_tx = (
@@ -85,13 +92,26 @@ def create_and_delete_token():
             .sign(admin_key)     # Sign with the same admin key used to create it
         )
 
-        delete_receipt = delete_tx.execute(client)
-        print(f"✅ Success! Token deleted.")
+        delete_tx.execute(client)
+        print("✅ Success! Token deleted.")
 
-    except Exception as e:
+    except (ValueError, TypeError) as e:
         print(f"❌ Error deleting token: {e}")
         sys.exit(1)
 
+def main():
+    """
+    1. Call create_new_token() to create a new token and get its admin key, token ID, client, and operator key.
+    2. Build a TokenDeleteTransaction using the token ID.
+    3. Freeze the transaction with the client.
+    4. Sign the transaction with both the operator key and the admin key.
+    5. Execute the transaction to delete the token.
+    6. Print the result or handle any errors.
+    """
+    client, operator_id, operator_key = setup_client()
+    admin_key = generate_admin_key()
+    token_id_to_delete = create_new_token(client, operator_id, operator_key, admin_key)
+    delete_token(admin_key, token_id_to_delete, client, operator_key)
 
 if __name__ == "__main__":
-    create_and_delete_token()
+    main()

examples/token_dissociate.py

@@ -1,7 +1,8 @@
+# uv run examples/token_dissociate.py
+# python examples/token_dissociate.py
 """
-uv run examples/token_dissociate.py
-python examples/token_dissociate.py
-
+A full example that creates an account, two tokens, associates them,
+and finally dissociates them.
 """
 import os
 import sys
@@ -17,36 +18,36 @@
     TokenCreateTransaction,
     TokenAssociateTransaction,
     TokenDissociateTransaction,
+    TokenType,
+    AccountInfoQuery,
+    ResponseCode,
 )
 
 # Load environment variables from .env file
 load_dotenv()
 
-
-def token_dissociate():
-    """
-    A full example that creates an account, two tokens, associates them,
-    and finally dissociates them.
-    """
-    # 1. Setup Client
-    # =================================================================
+def setup_client():
+    """Setup Client"""
     print("Connecting to Hedera testnet...")
     client = Client(Network(network='testnet'))
 
     try:
         operator_id = AccountId.from_string(os.getenv('OPERATOR_ID'))
         operator_key = PrivateKey.from_string(os.getenv('OPERATOR_KEY'))
         client.set_operator(operator_id, operator_key)
+        return client, operator_id, operator_key
+
     except (TypeError, ValueError):
         print("❌ Error: Please check OPERATOR_ID and OPERATOR_KEY in your .env file.")
         sys.exit(1)
 
     print(f"Using operator account: {operator_id}")
 
-    # 2. Create a new account to associate/dissociate with
-    # =================================================================
+def create_new_account(client, operator_id, operator_key):
+    """Create a new account to associate/dissociate with tokens"""
     print("\nSTEP 1: Creating a new account...")
-    recipient_key = PrivateKey.generate("ed25519")
+    recipient_key = PrivateKey.generate_ed25519()
+
     try:
         # Build the transaction
         tx = (
@@ -59,65 +60,128 @@ def token_dissociate():
         receipt = tx.freeze_with(client).sign(operator_key).execute(client)
         recipient_id = receipt.account_id
         print(f"✅ Success! Created new account with ID: {recipient_id}")
-    except Exception as e:
+        return client, operator_key, recipient_id, recipient_key, operator_id
+
+    except (ValueError, RuntimeError) as e:
         print(f"❌ Error creating new account: {e}")
         sys.exit(1)
-
-    # 3. Create two new tokens
-    # =================================================================
+def create_token(client, operator_key, recipient_id, recipient_key, operator_id):
+    """Create two new tokens (one NFT and one fungible) for demonstration purposes. """
     print("\nSTEP 2: Creating two new tokens...")
     try:
-        # Create First Token
-        tx1 = TokenCreateTransaction().set_token_name("First Token").set_token_symbol("TKA").set_initial_supply(1).set_treasury_account_id(operator_id)
-        receipt1 = tx1.freeze_with(client).sign(operator_key).execute(client)
-        token_id_1 = receipt1.token_id
-
-        # Create Second Token
-        tx2 = TokenCreateTransaction().set_token_name("Second Token").set_token_symbol("TKB").set_initial_supply(1).set_treasury_account_id(operator_id)
-        receipt2 = tx2.freeze_with(client).sign(operator_key).execute(client)
-        token_id_2 = receipt2.token_id
-
-        print(f"✅ Success! Created tokens: {token_id_1} and {token_id_2}")
-    except Exception as e:
+        # Generate supply key for NFT
+        supply_key = PrivateKey.generate_ed25519()
+        # Create NFT Token
+        nft_tx = (
+            TokenCreateTransaction()
+            .set_token_name("NFT Token")
+            .set_token_symbol("NFTK")
+            .set_token_type(TokenType.NON_FUNGIBLE_UNIQUE)
+            .set_initial_supply(0)
+            .set_treasury_account_id(operator_id)
+            .set_supply_key(supply_key)
+        )
+        nft_receipt = nft_tx.freeze_with(client).sign(operator_key).execute(client)
+        nft_token_id = nft_receipt.token_id
+
+        # Create Fungible Token
+        fungible_tx = (
+            TokenCreateTransaction()
+            .set_token_name("Fungible Token")
+            .set_token_symbol("FTK")
+            .set_initial_supply(1)
+            .set_treasury_account_id(operator_id)
+        )
+        fungible_receipt = fungible_tx.freeze_with(client).sign(operator_key).execute(client)
+        fungible_token_id = fungible_receipt.token_id
+
+        print(f"✅ Success! Created NFT token: {nft_token_id} and fungible token: {fungible_token_id}")
+        return client, nft_token_id, fungible_token_id, recipient_id, recipient_key
+
+    except (ValueError, RuntimeError) as e:
         print(f"❌ Error creating tokens: {e}")
         sys.exit(1)
 
-    # 4. Associate the tokens with the new account
-    # =================================================================
-    print(f"\nSTEP 3: Associating tokens with account {recipient_id}...")
+def token_associate(client, nft_token_id, fungible_token_id, recipient_id, recipient_key):
+    """
+    Associate the tokens with the new account.
+
+    Note: Tokens must be associated with an account before they can be used or dissociated.
+    Association is a prerequisite for holding, transferring, or later dissociating tokens.
+    """
+
+    print(f"\nSTEP 3: Associating NFT and fungible tokens with account {recipient_id}...")
+    print("Note: Tokens must be associated with an account before they can be used or dissociated.")
     try:
         receipt = (
             TokenAssociateTransaction()
             .set_account_id(recipient_id)
-            .add_token_id(token_id_1)
-            .add_token_id(token_id_2)
+            .add_token_id(nft_token_id)
+            .add_token_id(fungible_token_id)
             .freeze_with(client)
             .sign(recipient_key)  # Recipient must sign to approve
             .execute(client)
         )
         print(f"✅ Success! Token association complete. Status: {receipt.status}")
-    except Exception as e:
+        return client, nft_token_id, fungible_token_id, recipient_id, recipient_key
+    except (ValueError, RuntimeError) as e:
         print(f"❌ Error associating tokens: {e}")
         sys.exit(1)
 
-    # 5. Dissociate the tokens from the new account
-    # =================================================================
-    print(f"\nSTEP 4: Dissociating tokens from account {recipient_id}...")
+def verify_dissociation(client, nft_token_id, fungible_token_id, recipient_id):
+    """Verify that the specified tokens are dissociated from the account."""
+    print("\nVerifying token dissociation...")
+    info = AccountInfoQuery().set_account_id(recipient_id).execute(client)
+    associated_tokens = [rel.token_id for rel in getattr(info, 'token_relationships', [])]
+    if nft_token_id not in associated_tokens and fungible_token_id not in associated_tokens:
+        print("✅ Verified: Both tokens are dissociated from the account.")
+    else:
+        print("❌ Verification failed: Some tokens are still associated.")
+
+def token_dissociate(client, nft_token_id, fungible_token_id, recipient_id, recipient_key):
+    """
+    Dissociate the tokens from the new account.
+
+    Why dissociate?
+    - To remove unwanted tokens from your account
+    - To reduce account costs (some tokens may incur fees)
+    - For security or privacy reasons
+    - To comply with business or regulatory requirements
+    """
+
+    print(f"\nSTEP 4: Dissociating NFT and fungible tokens from account {recipient_id}...")
     try:
         receipt = (
             TokenDissociateTransaction()
             .set_account_id(recipient_id)
-            .add_token_id(token_id_1)
-            .add_token_id(token_id_2)
+            .add_token_id(nft_token_id)
+            .add_token_id(fungible_token_id)
             .freeze_with(client)
             .sign(recipient_key) # Recipient must sign to approve
             .execute(client)
         )
-        print(f"✅ Success! Token dissociation complete.")
-    except Exception as e:
+        print(f"✅ Success! Token dissociation complete for both NFT and fungible tokens, Status: {ResponseCode(receipt.status).name}")
+
+    except (ValueError, RuntimeError) as e:
         print(f"❌ Error dissociating tokens: {e}")
         sys.exit(1)
 
+def main():
+    """
+    1-create new account
+    2-create two tokens
+    3-associate the tokens with the new account
+    4-dissociate the tokens from the new account
+    5-verify dissociation
+    """
+    client, operator_id, operator_key = setup_client()
+    client, operator_key, recipient_id, recipient_key, operator_id =create_new_account(client, operator_id, operator_key)
+    client, nft_token_id, fungible_token_id, recipient_id, recipient_key = create_token(client, operator_key, recipient_id, recipient_key, operator_id)
+    token_associate(client, nft_token_id, fungible_token_id, recipient_id, recipient_key)
+    token_dissociate(client, nft_token_id, fungible_token_id, recipient_id, recipient_key)
+    # Optional: Verify dissociation
+    verify_dissociation(client, nft_token_id, fungible_token_id, recipient_id)
+
 
 if __name__ == "__main__":
-    token_dissociate()
+    main()