From 62fe93e88edf3b317fe2159b6f894bc25920aea6 Mon Sep 17 00:00:00 2001
From: dankito <git@dankito.net>
Date: Tue, 17 Sep 2024 17:23:30 +0200
Subject: [PATCH] Added example for reading TAN from command line

---
 README.md                                     | 29 +++++++++++++++++--
 .../client/fints4k/example/ShowUsage.kt       | 16 ++++++++--
 2 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index 03ced598..66b6aa3b 100644
--- a/README.md
+++ b/README.md
@@ -82,7 +82,10 @@ class ShowUsage {
 
 This fetches the booked account transactions of the last 90 days. In most cases no TAN is required for this.
 
-You can also specify options e.g. which transactions should be retrieved:
+
+#### GetAccountData parameter
+
+You can also specify options e.g. which transactions you would like to retrieve:
 
 ```kotlin
 val options = GetAccountDataOptions(
@@ -95,15 +98,35 @@ val options = GetAccountDataOptions(
 val response = client.getAccountData(options)
 ```
 
-Retrieving transactions older than 90 days requires a TAN, so add TAN handling in Client Callback:
+### TAN handling
+
+Retrieving transactions older than 90 days or sometimes even log in requires a TAN, so add TAN handling in Client Callback:
 
 ```kotlin
 val client = FinTs4kBankingClientForUser(bankCode, loginName, password, SimpleBankingClientCallback { tanChallenge, callback ->
-    val tan: String? = null // if a TAN is required, add a UI or ...
+    val tan: String? = null // if a TAN is required, read TAN from command line, add a UI, ...
     callback.invoke(EnterTanResult(tan)) // ...  set a break point here, get TAN e.g. from your TAN app, set tan variable in debugger view and resume debugger
 })
 ```
 
+E.g. TAN handling on the command line:
+
+```kotlin
+println("Enter password for $bankCode:")
+val password = readln() // as an alternative for hard coding password; of course can also be done for bankCode and login name
+
+val client = FinTs4kBankingClientForUser(bankCode, loginName, password, SimpleBankingClientCallback { tanChallenge, callback ->
+    println("A TAN is required for ${tanChallenge.forAction}. Selected TAN method is '${tanChallenge.selectedTanMethod.displayName}'. Messsage of your credit institute:")
+    println(tanChallenge.messageToShowToUser)
+    println("Get TAN from your TAN app etc., enter it and press Enter (or press Enter without an input to abort process):")
+
+    val tan: String? = readlnOrNull().takeUnless { it.isNullOrBlank() } // map empty input to null to abort process
+    callback.invoke(EnterTanResult(tan))
+})
+```
+
+### Error handling
+
 Add some error handling by checking `response.error`:
 
 ```kotlin
diff --git a/SampleApp/src/main/kotlin/net/codinux/banking/client/fints4k/example/ShowUsage.kt b/SampleApp/src/main/kotlin/net/codinux/banking/client/fints4k/example/ShowUsage.kt
index 0651899c..b3d96f5c 100644
--- a/SampleApp/src/main/kotlin/net/codinux/banking/client/fints4k/example/ShowUsage.kt
+++ b/SampleApp/src/main/kotlin/net/codinux/banking/client/fints4k/example/ShowUsage.kt
@@ -42,9 +42,16 @@ class ShowUsage {
     }
 
     fun getAccountDataFullExample() {
+        println("Enter password for $bankCode:")
+        val password = readln() // as an alternative for hard coding password; of course can also be done for bankCode and login name
+
         val client = FinTs4kBankingClientForUser(bankCode, loginName, password, SimpleBankingClientCallback { tanChallenge, callback ->
-            val tan: String? = null // if a TAN is required, add a UI or ...
-            callback.invoke(EnterTanResult(tan)) // ...  set a break point here, get TAN e.g. from your TAN app, set tan variable in debugger view and resume debugger
+            println("A TAN is required for ${tanChallenge.forAction}. Selected TAN method is '${tanChallenge.selectedTanMethod.displayName}'. Messsage of your credit institute:")
+            println(tanChallenge.messageToShowToUser)
+            println("Get TAN from your TAN app etc., enter it and press Enter (or press Enter without an input to abort process):")
+
+            val tan: String? = readlnOrNull().takeUnless { it.isNullOrBlank() } // map empty input to null to abort process
+            callback.invoke(EnterTanResult(tan))
         })
 
         val options = GetAccountDataOptions(
@@ -65,7 +72,10 @@ class ShowUsage {
 
 
     fun updateAccountTransactions() {
-        val client = FinTs4kBankingClientForUser(bankCode, loginName, password, SimpleBankingClientCallback())
+        val client = FinTs4kBankingClientForUser(bankCode, loginName, password, SimpleBankingClientCallback { tanChallenge, callback ->
+            val tan: String? = readlnOrNull() // if a TAN is required, read TAN from command line, add a UI, ...
+            callback.invoke(EnterTanResult(tan)) // ...  set a break point here, get TAN e.g. from your TAN app, set tan variable in debugger view and resume debugger
+        })
 
         // simulate account transactions we retrieved last time
         val today = Clock.System.now().toLocalDateTime(TimeZone.currentSystemDefault()).date