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+Output Interface
+-----------------
+
+Output classes are responsible for submitting metrics gathered in a
+Logster run to a specific output. Each output class should implement
+at least the following method:
+
+* `submit(self, metrics)`: the submit method is invoked at the end of
+  each run, and is responsible for sending the collected metrics values
+  to the output backend.
+  The `metrics` parameter is an iterable of [MetricObject][metric_object]
+  objects.
+
+There's a base class provided at [logster.logster_helper.LogsterOutput][logsteroutput].
+If your output class extends LogsterOutput, it needs to provide an implementation
+for the `submit` method but will get access to the [get_metric_name][logster_output]
+function for generating metric names using supplied prefix/suffix options.
+
+
+Optionally, an output class can override the constructor:
+
+* `__init__(self, parser, options, logger)`: The output is instantiated
+  before invoking the parser on new log lines.
+  Parameters: `parser` is the optparse.OptionParser instance, `options`
+  are the parsed optparse options, `logger` is the python logging instance
+
+If your ouput needs to take custom options on the commandline, it can implement
+the `add_options` classmethod to add its own options to an optparse.OptionParser
+instance:
+
+* @classmethod
+  `add_options(cls, parser)`: Called during optparse option parsing to add custom
+  commandline options for this output.
+  Parameters: `parser` is teh optparse.OptionParser instance.
+
+
+[metric_object]: ../logster/logster_helper.py
+[logster_output]: ../logster/logster_helper.py