Make gen string from PyrscopeSettings testable

And test it!

deployment/config.go

@@ -108,6 +108,20 @@ type PyroscopeSettings struct {
 	EnableAgentProfiling bool `default:"true"`
 }
 
+func (ps PyroscopeSettings) GenString(template string, mmTargets, ltTargets []string) string {
+	pyroscopeAppConfig := ""
+	if ps.EnableAppProfiling {
+		pyroscopeAppConfig = strings.Join(mmTargets, ",")
+	}
+	pyroscopeAgentsConfig := ""
+	if ps.EnableAgentProfiling {
+		pyroscopeAgentsConfig = strings.Join(ltTargets, ",")
+	}
+	pyroscopeConfigFile := fmt.Sprintf(template, pyroscopeAppConfig, pyroscopeAgentsConfig)
+
+	return pyroscopeConfigFile
+}
+
 // TerraformDBSettings contains the necessary data
 // to configure an instance to be deployed
 // and provisioned.

deployment/terraform/metrics.go

@@ -140,16 +140,8 @@ func (t *Terraform) setupMetrics(extAgent *ssh.ExtAgent) error {
 		return fmt.Errorf("error upload prometheus config: output: %s, error: %w", out, err)
 	}
 
-	pyroscopeAppConfig := ""
-	if t.config.PyroscopeSettings.EnableAppProfiling {
-		pyroscopeAppConfig = strings.Join(mmTargets, ",")
-	}
-	pyroscopeAgentsConfig := ""
-	if t.config.PyroscopeSettings.EnableAppProfiling {
-		pyroscopeAgentsConfig = strings.Join(ltTargets, ",")
-	}
 	mlog.Info("Updating Pyroscope config", mlog.String("host", t.output.MetricsServer.PublicIP))
-	pyroscopeConfigFile := fmt.Sprintf(pyroscopeConfig, pyroscopeAppConfig, pyroscopeAgentsConfig)
+	pyroscopeConfigFile := t.config.PyroscopeSettings.GenString(pyroscopeConfig, mmTargets, ltTargets)
 
 	rdr = strings.NewReader(pyroscopeConfigFile)
 	if out, err := sshc.Upload(rdr, "/etc/pyroscope/server.yml", true); err != nil {

deployment/terraform/strings_test.go

@@ -0,0 +1,101 @@
+package terraform
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+	"testing"
+
+	"github.com/mattermost/mattermost-load-test-ng/deployment"
+	"github.com/stretchr/testify/require"
+)
+
+var reListElems = regexp.MustCompile(`\[(.*)\]`)
+
+func TestPyroscopeSettingsGenString(t *testing.T) {
+	mmTarget := "app-0:8067"
+	ltTarget := "agent-0:4000"
+
+	// The Name represents the state of each setting, with
+	// 1 meaning true for bool and non-empty for []string,
+	// and 0 meaning false for bool and empty for []string
+	testCases := []struct {
+		Name                 string
+		EnableAppProfiling   bool
+		EnableAgentProfiling bool
+		MMTargets            []string
+		LTTargets            []string
+	}{
+		{"0000", false, false, []string{}, []string{}},
+		{"0001", false, false, []string{}, []string{ltTarget}},
+		{"0010", false, false, []string{mmTarget}, []string{}},
+		{"0011", false, false, []string{mmTarget}, []string{ltTarget}},
+		{"0100", false, true, []string{}, []string{}},
+		{"0101", false, true, []string{}, []string{ltTarget}},
+		{"0110", false, true, []string{mmTarget}, []string{}},
+		{"0111", false, true, []string{mmTarget}, []string{ltTarget}},
+		{"1000", true, false, []string{}, []string{}},
+		{"1001", true, false, []string{}, []string{ltTarget}},
+		{"1010", true, false, []string{mmTarget}, []string{}},
+		{"1011", true, false, []string{mmTarget}, []string{ltTarget}},
+		{"1100", true, true, []string{}, []string{}},
+		{"1101", true, true, []string{}, []string{ltTarget}},
+		{"1110", true, true, []string{mmTarget}, []string{}},
+		{"1111", true, true, []string{mmTarget}, []string{ltTarget}},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.Name, func(t *testing.T) {
+			settings := deployment.PyroscopeSettings{
+				EnableAppProfiling:   tc.EnableAppProfiling,
+				EnableAgentProfiling: tc.EnableAgentProfiling,
+			}
+
+			generatedYaml := settings.GenString(pyroscopeConfig, tc.MMTargets, tc.LTTargets)
+
+			// We need to do some parsing here to get the part we're interested in, which is the targets
+			// for the app nodes (the first 'targets: [...]' line), and the targets for the agent nodes,
+			// (the second 'targets: [...]' line), and then we extract everything that is inside the
+			// square brackets
+			targets := []string{}
+			for _, line := range strings.Split(generatedYaml, "\n") {
+				if strings.Contains(line, "targets") {
+					matches := reListElems.FindStringSubmatch(line)
+					fmt.Println(matches)
+					require.Len(t, matches, 2)
+					targets = append(targets, matches[1])
+				}
+			}
+			require.Len(t, targets, 2)
+
+			// Now we need to reconstruct the slice of targets for the app nodes
+			actualMMTargets := []string{}
+			mmTargets := targets[0]
+			if mmTargets != "" {
+				actualMMTargets = strings.Split(mmTargets, ",")
+			}
+
+			// And the same for the agent nodes
+			actualLTTargets := []string{}
+			ltTargets := targets[1]
+			if ltTargets != "" {
+				actualLTTargets = strings.Split(ltTargets, ",")
+			}
+
+			// Now's time to check the targets for the app nodes
+			if tc.EnableAppProfiling {
+				require.ElementsMatch(t, tc.MMTargets, actualMMTargets)
+			} else {
+				require.Empty(t, actualMMTargets)
+			}
+
+			// And again for the agent nodes
+			if tc.EnableAgentProfiling {
+				require.ElementsMatch(t, tc.LTTargets, actualLTTargets)
+			} else {
+				require.Empty(t, actualLTTargets)
+			}
+		})
+	}
+
+}