Merge pull request #217699 from PallabPaul/pallabpaul/confidential-ledger-python-quickstart-fix

[Confidential Ledger] Update Python Quickstart Document

Author: prmerger-automator[bot]

articles/confidential-ledger/quickstart-python.md

@@ -97,7 +97,7 @@ We'll finish setup by setting some variables for use in your application: the re
   > Each ledger must have a globally unique name. Replace \<your-unique-ledger-name\> with the name of your ledger in the following example.
 
 ```python
-resource_group = "myResourceGroup"
+resource_group = "<azure-resource-group>"
 ledger_name = "<your-unique-ledger-name>"
 subscription_id = "<azure-subscription-id>"
 
@@ -166,7 +166,7 @@ network_identity = identity_client.get_ledger_identity(
 
 ledger_tls_cert_file_name = "networkcert.pem"
 with open(ledger_tls_cert_file_name, "w") as cert_file:
-    cert_file.write(network_identity.ledger_tls_certificate)
+    cert_file.write(network_identity['ledgerTlsCertificate'])
 ```
 
 Now we can use the network certificate, along with the ledger URL and our credentials, to create a confidential ledger client.
@@ -179,21 +179,29 @@ ledger_client = ConfidentialLedgerClient(
 )
 ```
 
-We are prepared to write to the ledger.  We will do so using the `create_ledger_entry` function.
+We are prepared to write to the ledger. We will do so using the `create_ledger_entry` function.
 
 ```python
-append_result = ledger_client.create_ledger_entry(entry_contents="Hello world!")
-print(append_result.transaction_id)
+sample_entry = {"contents": "Hello world!"}
+append_result = ledger_client.create_ledger_entry(entry=sample_entry)
+print(append_result['transactionId'])
 ```
 
 The print function will return the transaction ID of your write to the ledger, which can be used to retrieve the message you wrote to the ledger.
 
 ```python
-latest_entry = ledger_client.get_current_ledger_entry(transaction_id=append_result.transaction_id)
+entry = ledger_client.get_ledger_entry(transaction_id=append_result['transactionId'])['entry']
+print(f"Entry (transaction id = {entry['transactionId']}) in collection {entry['collectionId']}: {entry['contents']}")
+```
+
+If you would simply like the latest transaction that was committed to the ledger, you can use the `get_current_ledger_entry` function.
+
+```python
+latest_entry = ledger_client.get_current_ledger_entry()
 print(f"Current entry (transaction id = {latest_entry['transactionId']}) in collection {latest_entry['collectionId']}: {latest_entry['contents']}")
 ```
 
-The print function will return "Hello world!", as that is the message in the ledger that that corresponds to the transaction ID.
+The print function will return "Hello world!", as that is the message in the ledger that that corresponds to the transaction ID and is the latest transaction.
 
 ## Full sample code
 
@@ -210,12 +218,11 @@ from azure.mgmt.confidentialledger.models import ConfidentialLedger
 
 from azure.confidentialledger import ConfidentialLedgerClient
 from azure.confidentialledger.certificate import ConfidentialLedgerCertificateClient
-from azure.confidentialledger import TransactionState
 
 # Set variables
 
-rg = "myResourceGroup"
-ledger_name = "<unique-ledger-name>"
+resource_group = "<azure-resource-group>"
+ledger_name = "<your-unique-ledger-name>"
 subscription_id = "<azure-subscription-id>"
 
 identity_url = "https://identity.confidential-ledger.core.azure.com"
@@ -250,14 +257,14 @@ ledger_properties = ConfidentialLedger(**properties)
 
 # Create a ledger
 
-confidential_ledger_mgmt.ledger.begin_create(rg, ledger_name, ledger_properties)
+confidential_ledger_mgmt.ledger.begin_create(resource_group, ledger_name, ledger_properties)
 
 # Get the details of the ledger you just created
 
-print(f"{rg} / {ledger_name}")
+print(f"{resource_group} / {ledger_name}")
 
 print("Here are the details of your newly created ledger:")
-myledger = confidential_ledger_mgmt.ledger.get(rg, ledger_name)
+myledger = confidential_ledger_mgmt.ledger.get(resource_group, ledger_name)
 
 print (f"- Name: {myledger.name}")
 print (f"- Location: {myledger.location}")
@@ -274,7 +281,7 @@ network_identity = identity_client.get_ledger_identity(
 
 ledger_tls_cert_file_name = "networkcert.pem"
 with open(ledger_tls_cert_file_name, "w") as cert_file:
-    cert_file.write(network_identity.ledger_tls_certificate)
+    cert_file.write(network_identity['ledgerTlsCertificate'])
 
 
 ledger_client = ConfidentialLedgerClient(
@@ -284,14 +291,35 @@ ledger_client = ConfidentialLedgerClient(
 )
 
 # Write to the ledger
-append_result = ledger_client.create_ledger_entry(entry_contents="Hello world!")
-print(append_result.transaction_id)
+sample_entry = {"contents": "Hello world!"}
+ledger_client.create_ledger_entry(entry=sample_entry)
 
 # Read from the ledger
-entry = ledger_client.get_current_ledger_entry(transaction_id=append_result.transaction_id)
+latest_entry = ledger_client.get_current_ledger_entry()
 print(f"Current entry (transaction id = {latest_entry['transactionId']}) in collection {latest_entry['collectionId']}: {latest_entry['contents']}")
 ```
 
+## Pollers
+
+If you would like to wait for your write transaction to be committed to your ledger you can use the `begin_create_ledger_entry` function. This will return a poller to wait until the entry is durably committed.
+
+```python
+sample_entry = {"contents": "Hello world!"}
+ledger_entry_poller = ledger_client.begin_create_ledger_entry( 
+    entry=sample_entry
+)
+ledger_entry_result = ledger_entry_poller.result()
+```
+
+Querying an older ledger entry requires the ledger to read the entry from disk and validate it. You can use the `begin_get_ledger_entry` function to create a poller that will wait until the queried entry is in a ready state to view.
+
+```python
+get_entry_poller = ledger_client.begin_get_ledger_entry(
+    transaction_id=ledger_entry_result['transactionId']
+)
+entry = get_entry_poller.result()
+```
+
 ## Clean up resources
 
 Other Azure confidential ledger articles can build upon this quickstart. If you plan to continue on to work with subsequent quickstarts and tutorials, you may wish to leave these resources in place.