{REST} Capture SSLError in handle_exception

[jiasli]

Description

Split from #14588.

In handle_exception, capture requests.exceptions.SSLError which is generated by directly calling requests's methods, and provide a better error message.

Testing Guide

Enable Fiddler HTTPS decryption and make az rest call like:

az rest -u 'https://management.azure.com/subscriptions/0b1f6471-1bf0-4dda-aec3-cb9272f09590/resourcegroups/fy?api-version=2018-02-01'

Output:

Request failed: Certificate verification failed. This typically happens when using Azure CLI behind a proxy that intercepts traffic with a self-signed certificate. Please add this certificate to the trusted CA bundle. More info: https://docs.microsoft.com/en-us/cli/azure/use-cli-effectively#work-behind-a-proxy.

Error detail: HTTPSConnectionPool(host='management.azure.com', port=443): Max retries exceeded with url: /subscriptions/0b1f6471-1bf0-4dda-aec3-cb9272f09590/resourcegroups/fy?api-version=2018-02-01 (Caused by SSLError(SSLError("bad handshake: Error([('SSL routines', 'tls_process_server_certificate', 'certificate verify failed')])")))

[yonzhan]

REST

[zhoxing-ms]

May I ask why the CLIError is not wrapped here any more?

[jiasli]

If we wrap the exception with CLIError, the exception type will be lost and

azure-cli/src/azure-cli-core/azure/cli/core/util.py

Line 82 in a0f8c8e

if isinstance(ex, (ClientRequestError, SSLError)):

won't be hit anymore.

We are leaving the error handing to handle_exception instead.

[zhoxing-ms]

Got it, thx~

[houk-ms]

Looks good. Add reference #14855

[zhoxing-ms]

LGTM

[arrownj]

Is it always SSLError ?

[jiasli]

No. We throw any exceptions and let handle_exception handle it.