Processor: Accumulate
The Accumulate processor used in IBA probes creates one number or discrete state time-series on output for each input with the same properties; each time the input changes, it takes its timestamp and value and appends them to the corresponding output series. If total duration (total_duration) is set and the length of the output time series in time is greater than duration, it removes old samples from the time series until this is no longer the case. If max samples (max_samples) is set and the length of the output time series in terms of number of samples is greater than max_samples, it removes old samples from the time series until this is no longer the case.
Parameter | Description |
---|---|
Input Types | Table (number or discrete state) |
Output Types | Table (number or discrete state, accumulate=True) |
Max Samples (max_samples) | Limits the maximum number of samples or an expression that evaluates to number of samples (default:1024) |
Total Duration (total_duration) | Limits the number of samples by their total duration. (in seconds) or an expression that evaluates to number of seconds (default:0) |
Graph Query (graph_query) |
One or more queries on graph specified as strings, or a list of such queries. (String will be deprecated in a future release.) Multiple queries should provide all the named nodes referenced by the expression fields (including additional_properties). Graph query is executed on the "operation" graph. Results of the queries can be accessed using the "query_result" variable with the appropriate index. For example, if querying property set nodes under name "ps", the result will be available as "query_result[0]["ps"]". In collector processors ( In other processors it is used for general parameterization and it is only supported as a list of queries. graph_query: "node("system", role="leaf", name="system"). out("hosted_interfaces"). node("interface", name="iface").out("link"). node("link", role="spine_leaf")" graph_query: ["node("system", role="leaf", name="system")", "node("system", role="spine", name="system")"] Non-collector processors containing the
graph_query: [node("property_set", label="probe_propset", name="ps")] duration: int(query_result[0]["ps"].values["accumulate_duration"]) Another example is a that probes can validate a compliance requirement; the compliance value may change over time and/or it can be used by more than one probe. Also, a probe can validate NOS versions on devices. In this case, property sets can be used to define the current NOS version requirement. If it changes tomorrow: change the property set value, instead of going under the probe stage. |
Enable Streaming (enable_streaming) | Makes samples of output stages streamed if enabled. An optional boolean that defaults to False. If set to True, all output stages of this processor are streamed in the generic protobuf schema. |
Example: Accumulate
Assume a configuration of
max_samples: 3 total_duration: 0
Assume the following input at time t=1
[if_name=eth0] : "up" [if_name=eth1] : "down" [if_name=eth3] : "up"
We have the following output at time t=1
[if_name=eth0] : [{"up", 1 second"}] [if_name=eth1] : [{"down", 1 second"}] [if_name=eth3] : [{"up", 1 second"}]
Assume the following input at time t=2
[if_name=eth0] : "down" [if_name=eth1] : "down" [if_name=eth3] : "up"
We have the following output at time t=2
[if_name=eth0] : [{"up", 1 second"}, {"down", 2 seconds"}] [if_name=eth1] : [{"down", 1 second"}] [if_name=eth3] : [{"up", 1 second"}]
Assume the following input at time t=3
[if_name=eth0] : "up" [if_name=eth1] : "down" [if_name=eth3] : "up"
We have the following output at time t=3
[if_name=eth0] : [{"up", 1 second"}, {"down", 2 seconds"}, {"up", 3 seconds"}] [if_name=eth1] : [{"down", 1 second"}] [if_name=eth3] : [{"up", 1 second"}]
Assume the following input at time t=4
[if_name=eth0] : "down" [if_name=eth1] : "down" [if_name=eth3] : "up"
We have the following output at time t=4
[if_name=eth0] : [{"down", 2 seconds"}, {"up", 3 seconds"}, {"down", 4 seconds"}] [if_name=eth1] : [{"down", 1 second"}] [if_name=eth3] : [{"up", 1 second"}]
If the expressions are used for max_samples or total_duration, then they are evaluated for each input item and the corresponding key is added for each output item.
max_samples: context.ref_max_samples * 2 total_duration: context.ref_duration * 2
Sample input:
[if_name=eth0, ref_max_samples=10, ref_duration=60] : "up" [if_name=eth1, ref_max_samples=20, ref_duration=120] : "down"
Output
[if_name=eth0, max_samples=20, duration=120] : "up" [if_name=eth1, max_samples=40, duration=240] : "down"