Reporting provenance using Graphviz

The Graphviz project at AT&T Research created the DOT language for graph visualization. SPADE's Graphviz reporter ingests provenance that is emitted by SPADE's Graphviz storage, and is described by the fragment of DOT below.

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Supported fragment of DOT

graph	digraph [ ID ] '{' statement_list '}'
statement_list	[ statement [ ';' ] [ statement_list ] ]
statement	node_statement | edge_statement | attribute_statement
attribute_statement	( graph | node | edge ) attribute_list
attribute_list	'[' [ a_list ] ']' [ attribute_list ]
a_list	ID '=' ID [ ( ';' | ',' ) ] [ a_list ]
edge_statement	node_id '->' node_id [ attribute_list ]
node_statement	node_id [ attribute_list ]
node_id	ID

"Terminals are shown in bold font and nonterminals in italics. Literal characters are given in single quotes. Parentheses ( and ) indicate grouping. Square brackets [ and ] enclose optional items. Vertical bars separate alternatives." An ID can be an alphanumeric string or a numeral.

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Configuring Graphviz reporting

The Graphviz reporter takes a single argument, which is the location in the filesystem where the Graphviz file is located. Note that this must be done in the SPADE controller (after the SPADE server has been started):

-> add reporter Graphviz /tmp/provenance.dot
Adding reporter Graphviz... done

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The reporter can be deactivated using the following command in the SPADE controller:

-> remove reporter Graphviz
Shutting down reporter Graphviz... done