Python agent release notesRSS

Fixes:

• Addressed a performance issue which would cause high CPU load, when parsing SQL queries which had a large number of values for a SQL 'IN' clause.
• Agent version was not reported in form A.B.C.D in all cases. This was causing UI to warn that Python agent was out of date even when running version newer than the minimum recommended version.
• When 'feedparser' module is used, now correctly track external web service requests where URI used 'feed' or feed:http' for scheme.
• Illegal non ASCII characters in a URL could cause the agent to generate Unicode conversion warnings or outright fail a request with an exception where the character sequence could not be decoded to Unicode using the Python system default encoding.
• The table name for a SQL query was not being correctly derived when the SQL contained a select sub query or table name aliases were being used.
• Number of nodes captured for a slow transaction trace was not being capped properly resulted in too much data being sent through to core application. This could result in details of slow transaction being rejected by core application, or result in a timeout in UI when attempting to display the slow transaction trace.
• SQL calls made using 'psycopg2' were failing where optional parameters argument was not supplied to database cursor 'execute()' method and the SQL contained a '%' character such as in a 'LIKE' clause.
• Was not ignoring exception of type 'bottle.HTTPError' raised within application using Bottle. This is not a true exception but is used to programmatically indicate a non 200 HTTP response so shouldn't have been recorded as an error.
• The 'django-piston' instrumentation was failing when an error occurred in users handler and it tried to generate an error response. This was because 'django-piston' was assuming that a handler would always be a normal function. It would therefore fail for a decorator/wrapper implemented using a class object as is used by the agent instrumentation.

New features:

• Added support for capturing explain plans for slow SQL when using MySQL and PostgreSQL.
• Added preliminary public API for manually instrumenting additional functions in user code and interacting with the current transaction to override how and what details about the transaction are recorded.
• Added the 'transaction_tracer.function_trace' setting in the agent configuration file for providing a simplified way of specifying additional Python functions for which time metrics should be collected. Time spent in these functions will then appear in web transaction performance break down and slow transaction traces.
• Added new or improved support for tracking external web service requests made using the 'urllib', 'urllib2', 'urllib3', 'httplib', 'httplib2' and 'requests' modules. Note that only time taken for the initial connect for the HTTP connection may be recorded. Uninstrumented time which appears immediately after an external web service request in a slow transaction trace made using one of these modules, will therefore possibly be the time then taken to send request data, wait for a response and consume that response data.
• Added support for tracking external requests to a Solr service using the 'pysolr' and 'solrpy' modules. Time spent making the request will show on the overview charts as Solr time. Metrics for individual types of requests will also be listed in web transaction performance breakdown and slow transaction traces.
• Added Django application called 'newrelic.extras.framework_django' which explicitly adds in 'newrelic_tags' tag library containing template tags for manually adding in RUM header and footer. Reliance on the old method whereby template tag library was added automatically is now deprecated and will be removed in a future version.
• Added support for Bottle 0.10.X in Bottle specific instrumentation.
• Added support for Redis using the 'redis' module. Support consists of tracking time spent connecting to and issuing commands against the Redis service.
• Added support for MongoDB using the 'pymongo' module. Support consists of tracking time spent connecting to and issuing commands against the MongoDB service.

Features changed:

• The 'capture_params' setting was defaulting to 'true' rather than 'false' resulting in the request query string parameters being reported against errors and slow transaction traces. If upgrading you will need to change the agent configuration file you are already using to change it to 'false' if capturing parameters is not desired.
• Rollup metrics against web transactions for external web service requests will now only be recorded against the host and will not be broken out based on resource requested on the remote service.

Fixes:

• Details of errors were not being captured and passed back to the core application to be displayed by the UI when the URL for the request had query string parameters. The problem was not causing failure of the overall web application but that a problem was occuring would have been identifiable though a Python agent exception and traceback being recorded in the Python agent log file with message:
• NameError: global name 'request_params' is not defined
• Slow transactions were never being recorded when agent run using method where no agent configuration file was being used. This is the case for example when using Heroku.

New features:

• Added support for the distributed task queuing system Celery. Tasks executed by a Celery server can be tracked and reported as background tasks against an application in the New Relic UI.
• Added support for tracking as external web service requests calls made out via the pywapi module.
• Added support for automatic wrapping of WSGI application entry point when using flup WSGI adapter for FASTCGI, SCGI and AJP.
• Added support for meinheld as standalone WSGI server and also as a worker class when using gunicorn.
• Added support for recording database transactions when using pyodbc.

Fixes:

• Where instrumentation was not available for the web framework or toolkit being used and web transactions were being named according to the original URL, metric normalization rules were not being correctly applied when metric grouping issues occurred due to a large number of unique URLs. This was resulting in grouping of web transactions metrics under incorrect names leading to the data presented by the UI being unhelpful or misleading.
• Agent would fail when collecting WSGI hosting environment information when an older version of Tornado web server was used which did not provide version information. This would lead to no web transactions metrics being reported as failure occured when agent was trying to register with the New Relic core application.
• Instrumentation of the feedparser module was not catering for the fact that the parse() function could be supplied arguments beyond just the URL to be retreived. This would result in an exception and the web transaction always failing when such additional arguments were supplied.
• Instrumentation for Django was improved so that view handler function name was reported against a web transaction rather than URL when using Django static files mechanism.
• Instrumentation for Django was improved so that technical 404 and 500 response handler function name was used for web transaction when appropriate.
• Instrumentation for Django was improved to ensure that request middleware function name was always used for web transaction name when it returned a valid response.

Features changed:

• Attributes captured from WSGI request environment such as 'REQUEST_METHOD', 'HTTP_REFERER' and 'HTTP_USER_AGENT' are now shown under the 'Request environment' category in error details and slow transaction traces rather than under 'Custom parameters'.
• The HTTP response status for a web transaction is now shown as 'STATUS' under the 'Response properties' category in error details and slow transaction traces rather than under 'Custom parameters'.