plugin-log-output

A plugin that delivers workflow execution output to console, files, and multiplexers. It provides unified output management through the Accumulator interface and visual workflow progress display using cowsay ASCII art.

Output Architecture

NodeActor / NodeGroupActor
        |
  MultiplexerAccumulator  (actor name: "outputMultiplexer")
        |
   +----+----+-----------+
   v         v            v
Console    File    DatabaseAccumulator
Accumulator Accumulator  (plugin-log-db)

MultiplexerAccumulator functions as a fan-out hub, simultaneously delivering a single output message to multiple targets.

ConsoleAccumulator

Outputs to console (standard output/standard error).

ConsoleAccumulator console = new ConsoleAccumulator();

// Custom output destination
ConsoleAccumulator console = new ConsoleAccumulator(System.out, System.err);

// Suppress output (only record count)
console.setQuiet(true);

// Output
console.add("node-web1", "stdout", "Deployment complete");
// Displays: [node-web1] Deployment complete

// stderr type outputs to System.err
console.add("node-web1", "stderr", "Warning: deprecated API");

// Summary
String summary = console.getSummary();
int count = console.getCount();

The output format is [source] data, with multi-line data having the prefix added to each line.

FileAccumulator

Outputs to a text file.

FileAccumulator file = new FileAccumulator(Path.of("./output.log"));

file.add("node-web1", "stdout", "Started");
// Immediately flushed to file

Path path = file.getFilePath();
int count = file.getCount();

// Close after use
file.close();

• Thread-safe (synchronized)
• Overwrites existing files
• Auto-flush after each output

MultiplexerAccumulator

Performs fan-out delivery to multiple targets.

MultiplexerAccumulator mux = new MultiplexerAccumulator();

// Add targets
mux.addTarget(consoleAccumulator);
mux.addTarget(fileAccumulator);
mux.addTarget(databaseAccumulator);

// Output (simultaneously delivered to all targets)
mux.add("node-web1", "stdout", "Deploy OK");

// Remove target
mux.removeTarget(fileAccumulator);

// Target count
int targets = mux.getTargetCount();

// Summary (combines summaries from all targets)
String summary = mux.getSummary();

Even if an exception occurs in one target, delivery to other targets continues.

MultiplexerAccumulatorActor

Registered within the actor system under the actor name "outputMultiplexer", allowing other actors to perform output via message sending.

@Action Methods

Action	Arguments (JSON)	Description
add	{source, type, data}	Deliver output message to all targets
getSummary	none	Get summary from all targets
getCount	none	Get cumulative output count
clear	none	Reset counter

MultiplexerLogHandler

A handler that forwards java.util.logging (JUL) logs to the multiplexer.

MultiplexerLogHandler handler = new MultiplexerLogHandler(actorSystem);
Logger.getLogger("").addHandler(handler);

Sends JUL log records to the multiplexer in the following format:

• Format: "timestamp LEVEL message"
• Type: "log-INFO", "log-WARNING", "log-SEVERE", etc.
• Source name mapping:
  • com.scivicslab.turingworkflow.* -> "turing-workflow"
  • com.scivicslab.pojoactor.* -> "pojo-actor"
  • Others -> simple class name

WorkflowStreamingAccumulator

A StreamingAccumulator that provides cowsay ASCII art display during workflow transitions.

WorkflowStreamingAccumulator acc = new WorkflowStreamingAccumulator();

// Set cowfile (optional)
acc.setCowfile("tux");       // tux penguin
acc.setCowfile("dragon");    // dragon
acc.setCowfile(null);        // default cow

// Render cowsay
String cowsay = acc.renderCowsay("deploy-workflow", "step: deploy\naction: kubectl apply");

Output example:

 ________________________________
/ [deploy-workflow]              \
| step: deploy                   |
\ action: kubectl apply          /
 --------------------------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

List available cowfiles:

String[] cowfiles = WorkflowStreamingAccumulator.listCowfiles();

Dependencies

• org.json:json:20231013 - JSON parsing
• com.github.ricksbrown:cowsay:1.1.0 - cowsay ASCII art
• No dependencies on other plugins