This release of the Python agent is a bug fix release which improves our introductory support for instrumenting Tornado 4 applications. Full details about the status of our Tornado 4 support can be found on our Introductory Tornado 4 support page.
For a list of known issues with the Python agent, see Status of the Python agent.
New attributes captured for Tornado 4 applications
The following attributes are now captured for requests made to Tornado 4 applications:
Potentially too many metrics created for
tornado.httpclientinstrumentation for Tornado 4 applications could cause a "metric grouping issue" in the function traces it created, if it was used to make requests to a large number of unique URLs. To address this issue, the URL is no longer included in the name of the function trace.
Transactions in Tornado 4 applications could be created with invalid agent settings
In the prior release, if a transaction started before the agent had completed registration with the collector, the transaction could have invalid settings, which would result in various errors in the agent log, including an
AttributeErrorwhen an external call was made during the transaction. These errors only happened at application startup until registration was complete. With this release, transactions cannot start with invalid settings.
httplib2instrumentation did not process the cross application tracing headers in the response
Failing to process the response headers resulted in the inability to link to cross application tracing details in the Transaction Trace Details view, as well as missing
ExternalAppmetrics. Now, the
httplib2instrumentation in the agent processes the cross application tracing headers correctly.
Known Tornado 4 Limitations Addressed
Explain plans for queries made with psycopg2's "async mode" are disabled automatically
Currently, the Python agent does not support explain plans for queries made in psycopg2's "async mode." In the prior release, it was necessary to add the configuration setting
transaction_tracer.explain_enabled = falseto disable explain plans, or else errors would occur during data harvest, potentially causing loss of data. With this release, the agent disables explain plans automatically when async mode is detected.
Added support for Synthetics Transaction Traces
Tornado 4 applications will now recognize incoming requests from Synthetics and generate transaction traces for Synthetic requests.
Status of Tornado 4 Support
A current list of known limitations can be found on our Introductory Tornado 4 support page. No new known limitations have been added since our introductory release (v18.104.22.168). In the next few releases, we plan to continue addressing these issues.