test plugin cancellation

Makefile

@@ -25,7 +25,8 @@ agent:
 
 .PHONY: build-plugin-examples
 build-plugin-examples:
-	$(GO_BUILD) -o $(BUILD_DIR)/$(CURRENT_ARCH)/plugin_examples/dummy ./plugin_examples/dummy.go
+	$(GO_BUILD) -o $(BUILD_DIR)/$(CURRENT_ARCH)/plugin_examples/dummy ./plugin_examples/dummy/dummy.go
+	$(GO_BUILD) -o $(BUILD_DIR)/$(CURRENT_ARCH)/plugin_examples/sleep ./plugin_examples/sleep/sleep.go
 
 .PHONY: cross-compiled $(ARCHS)
 cross-compiled: $(ARCHS)

plugin_examples/dummy.go → plugin_examples/dummy/dummy.go

@@ -1,6 +1,6 @@
 package main
 
-// go build -o /usr/etc/trento/dummy ./plugin_examples/dummy.go
+// go build -o /usr/etc/trento/dummy ./plugin_examples/dummy/dummy.go
 
 import (
 	"context"

plugin_examples/sleep/sleep.go

@@ -0,0 +1,65 @@
+package main
+
+// go build -o /usr/etc/trento/sleep ./plugin_examples/sleep/sleep.go
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+	"sync"
+
+	"github.com/hashicorp/go-plugin"
+	log "github.com/sirupsen/logrus"
+	"github.com/trento-project/agent/pkg/factsengine/entities"
+	"github.com/trento-project/agent/pkg/factsengine/plugininterface"
+)
+
+type sleepGatherer struct {
+}
+
+func (s sleepGatherer) Gather(ctx context.Context, factsRequests []entities.FactRequest) ([]entities.Fact, error) {
+	facts := []entities.Fact{}
+
+	log.Infof("Starting sleep plugin facts gathering process")
+
+	wg := sync.WaitGroup{}
+
+	for _, factReq := range factsRequests {
+		log.Infof("Sleeping for %s", factReq.Argument)
+		fact := entities.NewFactGatheredWithRequest(factReq, &entities.FactValueString{Value: fmt.Sprint(factReq.Argument)})
+		facts = append(facts, fact)
+
+		time := fmt.Sprint(factReq.Argument)
+		wg.Add(1)
+		go func(time string) {
+			defer wg.Done()
+			cmd := exec.CommandContext(ctx, "sleep", time)
+			cmd.Run()
+		}(time)
+
+	}
+
+	wg.Wait()
+
+	log.Infof("Requested sleep plugin facts gathered")
+	return facts, nil
+}
+
+func main() {
+	d := &sleepGatherer{}
+
+	handshakeConfig := plugin.HandshakeConfig{
+		ProtocolVersion:  1,
+		MagicCookieKey:   "TRENTO_PLUGIN",
+		MagicCookieValue: "gatherer",
+	}
+
+	var pluginMap = map[string]plugin.Plugin{
+		"gatherer": &plugininterface.GathererPlugin{Impl: d},
+	}
+
+	plugin.Serve(&plugin.ServeConfig{ // nolint
+		HandshakeConfig: handshakeConfig,
+		Plugins:         pluginMap,
+	})
+}

test/cli/plugins.bats

@@ -7,6 +7,10 @@ setup() {
     PATH="$BUILD_DIR:$PATH"
 }
 
+teardown() {
+    # kill all the processes started by the test
+    pkill -P $$ || true
+}
 
 @test "it should include the dummy plugin into list" {
     run trento-agent facts list --plugins-folder $BUILD_DIR/plugin_examples
@@ -32,3 +36,126 @@ setup() {
     [ "$status" -eq 0 ]
     echo $output | grep -q "Name: 2"
 }
+
+@test "it should remove all the processes on complete" {
+   # declare the expected processes
+   cmd_agent="trento-agent facts gather --plugins-folder $BUILD_DIR/plugin_examples --gatherer sleep --argument 2s"
+   cmd_plugin="$BUILD_DIR/plugin_examples/sleep"
+   cmd_sleep="sleep 2s"
+
+   # start the agent in background
+   eval "$cmd_agent &" 
+   pid=$!
+
+   # retrieve the pid of the exepcted process
+   pid_agent=$(pgrep -f "$cmd_agent")
+   pid_plugin=$(pgrep -f "$cmd_plugin")
+   pid_sleep=$(pgrep -f "$cmd_sleep")
+
+   # double check the test is correct
+   [ $pid -eq $pid_agent ]
+
+   # ensure no duplicated processes are running
+   assert_one "$pid_agent"
+   assert_one "$pid_plugin"
+   assert_one "$pid_sleep"
+
+   # ensure the process tree is correct
+   assert_parent "$pid_plugin" "$pid_agent"
+   assert_parent "$pid_sleep" "$pid_plugin"
+
+   # wait for the process to finish
+   while kill -0 $pid 2>/dev/null; do
+       sleep 1
+   done
+
+   # test processes are killed
+   assert_no_pid "$pid_agent"
+   assert_no_pid "$pid_plugin"
+   assert_no_pid "$pid_sleep"
+}
+
+@test "it should remove all the processes on agent process stopped (SIGINT)" {
+   # declare the expected processes
+   cmd_agent="trento-agent facts gather --plugins-folder $BUILD_DIR/plugin_examples --gatherer sleep --argument 2s"
+   cmd_plugin="$BUILD_DIR/plugin_examples/sleep"
+   cmd_sleep="sleep 2s"
+
+   # start the agent in background
+   eval "$cmd_agent &" 
+   pid=$!
+
+   # retrieve the pid of the exepcted process
+   pid_agent=$(pgrep -f "$cmd_agent")
+   pid_plugin=$(pgrep -f "$cmd_plugin")
+   pid_sleep=$(pgrep -f "$cmd_sleep")
+
+   # double check the test is correct
+   [ $pid -eq $pid_agent ]
+
+   # ensure no duplicated processes are running
+   assert_one "$pid_agent"
+   assert_one "$pid_plugin"
+   assert_one "$pid_sleep"
+
+   # ensure the process tree is correct
+   assert_parent "$pid_plugin" "$pid_agent"
+   assert_parent "$pid_sleep" "$pid_plugin"
+
+   # kill the agent
+   kill -INT $pid_agent
+
+   # test processes are killed
+   assert_no_pid "$pid_agent"
+   assert_no_pid "$pid_plugin"
+   assert_no_pid "$pid_sleep"
+}
+
+@test "it should remove all the processes on agent process stopped (SIGTERM)" {
+   # declare the expected processes
+   cmd_agent="trento-agent facts gather --plugins-folder $BUILD_DIR/plugin_examples --gatherer sleep --argument 2s"
+   cmd_plugin="$BUILD_DIR/plugin_examples/sleep"
+   cmd_sleep="sleep 2s"
+
+   # start the agent in background
+   eval "$cmd_agent &" 
+   pid=$!
+
+   # retrieve the pid of the exepcted process
+   pid_agent=$(pgrep -f "$cmd_agent")
+   pid_plugin=$(pgrep -f "$cmd_plugin")
+   pid_sleep=$(pgrep -f "$cmd_sleep")
+
+   # double check the test is correct
+   [ $pid -eq $pid_agent ]
+
+   # ensure no duplicated processes are running
+   assert_one "$pid_agent"
+   assert_one "$pid_plugin"
+   assert_one "$pid_sleep"
+
+   # ensure the process tree is correct
+   assert_parent "$pid_plugin" "$pid_agent"
+   assert_parent "$pid_sleep" "$pid_plugin"
+
+   # kill the agent
+   kill -TERM $pid_agent
+
+   # test processes are killed
+   assert_no_pid "$pid_agent"
+   assert_no_pid "$pid_plugin"
+   assert_no_pid "$pid_sleep"
+}
+
+
+function assert_one {
+    [ $(echo "$1" | wc -l)  == 1  ]
+}
+
+function assert_parent {
+    [ $(ps -o ppid= -p "$1") == "$2" ]
+}
+
+function assert_no_pid {
+    [ $(ps -p "$1" | wc -l) == 1 ]
+}