sandipchitale/build-task-graph.gradle

## build-task-graph.gradle
apply plugin: PrintTaskExecGraphPlugin

import org.gradle.api.Plugin
import org.gradle.api.Project
import org.gradle.api.execution.TaskExecutionGraph
import org.gradle.api.logging.Logger
import org.gradle.api.logging.Logging
import org.gradle.execution.taskgraph.TaskExecutionPlan
import org.gradle.execution.taskgraph.TaskInfo

import java.lang.reflect.Field

/**
 * Print Task Execution Graph
 *
 * <p>Gradle plugin printing Gradle task execution graphs.</p>
 *
 * @author Sandip Chitale
 */
class PrintTaskExecGraphPlugin implements Plugin<Project> {
    static final Logger LOG = Logging.getLogger(PrintTaskExecGraphPlugin.class)

    /** Platform dependent line separator */
    def ls = System.getProperty("line.separator")

    @Override
    void apply(Project project) {
        project.extensions.create("printteg", PrintTegPluginExtension)

        PrintTegPluginExtension printtegExt = project.printteg
        project.gradle.taskGraph.whenReady { g ->
            if (printtegExt.enabled) {
                // Access private variables of tasks graph
                def tep = getTEP(g)
                // Execution starts on these tasks
                def entryTasks = getEntryTasks(tep)
                // Create output buffer
                def dotGraph = new StringBuilder(
'''<!DOCTYPE html>
<html>
<head>
<title>Task Execution Graph</title>
</head>
<body>
<pre>''').append(ls)
                // Generate graph for each input
                entryTasks.each { et ->
                    def seen = new HashSet<String>()
                    printGraph(printtegExt, dotGraph, ls, et, seen, '', DependencyKind.DEPENDENCY, '')
                }
                dotGraph.append(ls)
                // Finalize graph
                dotGraph.append(
'''
</pre>
</body>
</html>
'''
).append(ls)

                // Save graph
                def outputFile = getDestination(project)
                outputFile.parentFile.mkdirs()
                outputFile.write(dotGraph.toString())

                LOG.info("PrintTEG: Dependency report written into $outputFile")
            }
        }
    }

    private File getDestination(Project p) {
        p.file(p.printteg.destination)
    }

    private TaskExecutionPlan getTEP(TaskExecutionGraph teg) {
        Field f = teg.getClass().getDeclaredField("taskExecutionPlan")
        f.setAccessible(true)
        f.get(teg)
    }

    private Set<TaskInfo> getEntryTasks(TaskExecutionPlan tep) {
        Field f = tep.getClass().getDeclaredField("entryTasks")
        f.setAccessible(true)
        Set<org.gradle.execution.taskgraph.TaskInfo> entryTasks = f.get(tep)
        entryTasks
    }

    void printGraph(PrintTegPluginExtension printtegExt,
                             StringBuilder sb,
                             String ls,
                             TaskInfo entry,
                             HashSet<String> seen,
                             String indent,
                             DependencyKind dependencyKind,
                             String dependee) {

        def ti = entry
        def tproject = ti.task.project
        def tname = ti.task.path
        def tdesc = ti.task.description

        def nodeKind = ti.dependencyPredecessors.empty ? NodeKind.START
                : ti.dependencySuccessors.empty ? NodeKind.END : NodeKind.INNER
        if (nodeKind == NodeKind.START && dependencyKind == DependencyKind.DEPENDENCY) {
            sb.append(indent).append('&#8614;')
        } else {
            sb.append(indent).append('&#x2516')
        }

        switch(dependencyKind) {
            case DependencyKind.MUST:
                sb.append(' must run after');
                break;
            case DependencyKind.SHOULD:
                sb.append(' should run after')
                break;
        }

        sb.append(" $tname")
        if (tdesc != null) {
            sb.append(" - $tdesc")
        }

        switch(dependencyKind) {
            case DependencyKind.FINALIZER:
                sb.append(' finalizes ' + dependee)
                break;
        }

        if (nodeKind == NodeKind.END) {
            sb.append(' &#8867;')
        }
        try {
            if (seen.contains(tname)) {
                sb.append(' &#x2191;')
                return
            }
        } finally {
            sb.append(ls)
        }

        seen.add(tname)

        indent += '   '

        ti.dependencySuccessors.each {succ ->
            def sname = succ.task.path
            printGraph(printtegExt, sb, ls, succ, seen, indent, DependencyKind.DEPENDENCY, null)
        }

        ti.finalizers.each {succ ->
            def sname = succ.task.path
            printGraph(printtegExt, sb, ls, succ, seen, indent, DependencyKind.FINALIZER, tname)
        }

        ti.mustSuccessors.each {succ ->
            def sname = succ.task.path
            printGraph(printtegExt, sb, ls, succ, seen, indent, DependencyKind.MUST, tname)
        }

        ti.shouldSuccessors.each {succ ->
            def sname = succ.task.path
            printGraph(printtegExt, sb, ls, succ, seen, indent, DependencyKind.SHOULD, tname)
        }

    }

    String edgeHash(String from, String to) {
        return from.hashCode()*37 + to.hashCode()
    }

    enum NodeKind {
        START, INNER, END
    }

    enum DependencyKind {
        DEPENDENCY, MUST, SHOULD, FINALIZER
    }
}

class PrintTegPluginExtension {
    /** Enables the plugin for given project */
    boolean enabled = true
    /** Output file destination file */
    String destination = 'build/reports/printteg.html'
}
	apply plugin: PrintTaskExecGraphPlugin

	import org.gradle.api.Plugin
	import org.gradle.api.Project
	import org.gradle.api.execution.TaskExecutionGraph
	import org.gradle.api.logging.Logger
	import org.gradle.api.logging.Logging
	import org.gradle.execution.taskgraph.TaskExecutionPlan
	import org.gradle.execution.taskgraph.TaskInfo

	import java.lang.reflect.Field

	/**
	* Print Task Execution Graph
	*
	* <p>Gradle plugin printing Gradle task execution graphs.</p>
	*
	* @author Sandip Chitale
	*/
	class PrintTaskExecGraphPlugin implements Plugin<Project> {
	static final Logger LOG = Logging.getLogger(PrintTaskExecGraphPlugin.class)

	/** Platform dependent line separator */
	def ls = System.getProperty("line.separator")

	@Override
	void apply(Project project) {
	project.extensions.create("printteg", PrintTegPluginExtension)

	PrintTegPluginExtension printtegExt = project.printteg
	project.gradle.taskGraph.whenReady { g ->
	if (printtegExt.enabled) {
	// Access private variables of tasks graph
	def tep = getTEP(g)
	// Execution starts on these tasks
	def entryTasks = getEntryTasks(tep)
	// Create output buffer
	def dotGraph = new StringBuilder(
	'''<!DOCTYPE html>
	<html>
	<head>
	<title>Task Execution Graph</title>
	</head>
	<body>
	<pre>''').append(ls)
	// Generate graph for each input
	entryTasks.each { et ->
	def seen = new HashSet<String>()
	printGraph(printtegExt, dotGraph, ls, et, seen, '', DependencyKind.DEPENDENCY, '')
	}
	dotGraph.append(ls)
	// Finalize graph
	dotGraph.append(
	'''
	</pre>
	</body>
	</html>
	'''
	).append(ls)

	// Save graph
	def outputFile = getDestination(project)
	outputFile.parentFile.mkdirs()
	outputFile.write(dotGraph.toString())

	LOG.info("PrintTEG: Dependency report written into $outputFile")
	}
	}
	}

	private File getDestination(Project p) {
	p.file(p.printteg.destination)
	}

	private TaskExecutionPlan getTEP(TaskExecutionGraph teg) {
	Field f = teg.getClass().getDeclaredField("taskExecutionPlan")
	f.setAccessible(true)
	f.get(teg)
	}

	private Set<TaskInfo> getEntryTasks(TaskExecutionPlan tep) {
	Field f = tep.getClass().getDeclaredField("entryTasks")
	f.setAccessible(true)
	Set<org.gradle.execution.taskgraph.TaskInfo> entryTasks = f.get(tep)
	entryTasks
	}

	void printGraph(PrintTegPluginExtension printtegExt,
	StringBuilder sb,
	String ls,
	TaskInfo entry,
	HashSet<String> seen,
	String indent,
	DependencyKind dependencyKind,
	String dependee) {

	def ti = entry
	def tproject = ti.task.project
	def tname = ti.task.path
	def tdesc = ti.task.description

	def nodeKind = ti.dependencyPredecessors.empty ? NodeKind.START
	: ti.dependencySuccessors.empty ? NodeKind.END : NodeKind.INNER
	if (nodeKind == NodeKind.START && dependencyKind == DependencyKind.DEPENDENCY) {
	sb.append(indent).append('↦')
	} else {
	sb.append(indent).append('&#x2516')
	}

	switch(dependencyKind) {
	case DependencyKind.MUST:
	sb.append(' must run after');
	break;
	case DependencyKind.SHOULD:
	sb.append(' should run after')
	break;
	}

	sb.append(" $tname")
	if (tdesc != null) {
	sb.append(" - $tdesc")
	}

	switch(dependencyKind) {
	case DependencyKind.FINALIZER:
	sb.append(' finalizes ' + dependee)
	break;
	}

	if (nodeKind == NodeKind.END) {
	sb.append(' ⊣')
	}
	try {
	if (seen.contains(tname)) {
	sb.append(' ↑')
	return
	}
	} finally {
	sb.append(ls)
	}

	seen.add(tname)

	indent += ' '

	ti.dependencySuccessors.each {succ ->
	def sname = succ.task.path
	printGraph(printtegExt, sb, ls, succ, seen, indent, DependencyKind.DEPENDENCY, null)
	}

	ti.finalizers.each {succ ->
	def sname = succ.task.path
	printGraph(printtegExt, sb, ls, succ, seen, indent, DependencyKind.FINALIZER, tname)
	}

	ti.mustSuccessors.each {succ ->
	def sname = succ.task.path
	printGraph(printtegExt, sb, ls, succ, seen, indent, DependencyKind.MUST, tname)
	}

	ti.shouldSuccessors.each {succ ->
	def sname = succ.task.path
	printGraph(printtegExt, sb, ls, succ, seen, indent, DependencyKind.SHOULD, tname)
	}

	}

	String edgeHash(String from, String to) {
	return from.hashCode()*37 + to.hashCode()
	}

	enum NodeKind {
	START, INNER, END
	}

	enum DependencyKind {
	DEPENDENCY, MUST, SHOULD, FINALIZER
	}
	}

	class PrintTegPluginExtension {
	/** Enables the plugin for given project */
	boolean enabled = true
	/** Output file destination file */
	String destination = 'build/reports/printteg.html'
	}