[BUG] Azure core retry policy

[jiminwen-msft]

Describe the bug
Parent task with context: Task 2934101: [Android] requesting send message with no network, return no status code - Boards (visualstudio.com). I think the retry-policy library provided by azure-core needs to add checking for null response. Our clients are seeing NPE when the network is closed/poor. The reason is that there is no response in this situation, but retry-policy class still tries to get status code: azure-sdk-for-android/RetryPolicy.java at bd9aeea4b47c945943ca918c63a2d49015f66057 · Azure/azure-sdk-for-android (github.com).

Exception or Stack Trace
com.azure.android.core.http.policy.RetryPolicy.calculateRetryDelay(RetryPolicy.java:169)
com.azure.android.core.http.policy.RetryPolicy.retryIfRequired(RetryPolicy.java:129)
com.azure.android.core.http.policy.RetryPolicy.access$000(RetryPolicy.java:23)
com.azure.android.core.http.policy.RetryPolicy$1.onError(RetryPolicy.java:92)
com.azure.android.core.http.HttpPipelinePolicyChainImpl.completedError(HttpPipelinePolicyChainImpl.java:202)
com.azure.android.core.http.PolicyCompleter.completedError(PolicyCompleter.java:53)
com.azure.android.core.http.policy.CookiePolicy$1.onError(CookiePolicy.java:81)
com.azure.android.core.http.policy.CookiePolicy$1.onError(CookiePolicy.java:81)
com.azure.android.core.http.HttpPipelinePolicyChainImpl.completedError(HttpPipelinePolicyChainImpl.java:202)
com.azure.android.core.http.HttpPipelinePolicyChainImpl.completedError(HttpPipelinePolicyChainImpl.java:208)
com.azure.android.core.http.PolicyCompleter.completedError(PolicyCompleter.java:53)
com.azure.android.core.http.policy.HttpLoggingPolicy$1.onError(HttpLoggingPolicy.java:202)
...(Skipping a few lines)
...
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1137)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:637)
java.lang.Thread.run(Thread.java:1012)

To Reproduce
Steps to reproduce the behavior:
Using chat SDK sample APP:

1. Close the network
2. Run chat sample APP
3. Send new message using the APP

Code Snippet

azure-sdk-for-android/sdk/core/azure-core-http/src/main/java/com/azure/android/core/http/policy/RetryPolicy.java

Line 169 in bd9aeea

final int code = response.getStatusCode();

Expected behavior
NPE being thrown

Screenshots
If applicable, add screenshots to help explain your problem.

Setup (please complete the following information):

• OS: Android
• IDE : Android Studio
• Version of the Library used: azureCoreVersion = "1.0.0-beta.10"

Additional context
Add any other context about the problem here.

Information Checklist
Kindly make sure that you have added all the following information above and checkoff the required fields otherwise we will treat the issuer as an incomplete report

• [Y ] Bug Description Added
• [Y ] Repro Steps Added
• [Y] Setup information Added

[vcolin7]

Hi @jiminwen-msft, I'm looking into this and should have a fix soon.