e2e_test: enable serial logs in cos to support ReportInventory test (#297)

* e2e_test: enable serial logs in cos to support ReportInventory test

* govet

Author: adjackura

e2e_tests/test_suites/inventoryreporting/inventory_reporting.go

@@ -20,6 +20,7 @@ import (
 	"log"
 	"path"
 	"regexp"
+	"strings"
 	"sync"
 	"time"
 
@@ -106,10 +107,14 @@ func runInventoryReportingTest(ctx context.Context, testSetup *inventoryTestSetu
 	// Build regexes for verification.
 	positivePatterns := []string{
 		fmt.Sprintf(`.*Calling ReportInventory with request containing hostname %s, short name %s, [1-9]+[0-9]* installed packages, [0-9]+ available packages`, testSetup.hostname, testSetup.shortName),
-		`.*"report_full_inventory".*true.*`,
 		`.*"report_full_inventory".*false.*`,
 		`.*Finished task "Report OSInventory".*`,
 	}
+	// Because COS does not output debug agent log to serial by default and we have to manually set
+	// that up on boot the agent will report full inventory before we can see the output.
+	if !strings.Contains(testSetup.image, "cos") {
+		positivePatterns = append(positivePatterns, `.*"report_full_inventory".*true.*`)
+	}
 	positiveRegexes, err := compileRegex(positivePatterns)
 	if err != nil {
 		testCase.WriteFailure("Error compiling ReportInventory RPC payload regex: %v", err)

e2e_tests/test_suites/inventoryreporting/test_setup.go

@@ -81,7 +81,7 @@ var (
 	}
 
 	cosSetup = &inventoryTestSetup{
-		startup:     compute.BuildInstanceMetadataItem("startup-script", utils.CurlPost),
+		startup:     compute.BuildInstanceMetadataItem("startup-script", utils.CosSetup),
 		machineType: "e2-standard-2",
 		timeout:     5 * time.Minute,
 	}

e2e_tests/utils/utils.go

@@ -56,6 +56,15 @@ sleep 5
 done
 systemctl start google-osconfig-agent` + CurlPost
 
+	// CosSetup sets up serial logging on COS.
+	CosSetup = `
+sleep 10
+sed -i 's/^#ForwardToConsole=no/ForwardToConsole=yes/' /etc/systemd/journald.conf
+sed -i 's/^#MaxLevelConsole=info/MaxLevelConsole=debug/' /etc/systemd/journald.conf
+MaxLevelConsole=debug
+systemctl force-reload systemd-journald
+systemctl restart google-osconfig-agent` + CurlPost
+
 	// CurlPost indicates agent is installed.
 	CurlPost = `
 uri=http://metadata.google.internal/computeMetadata/v1/instance/guest-attributes/osconfig_tests/install_done