Add os_family, os_platform and os_version to host provider (#5941)

This commit adds `os_family`, `os_platform` and `os_version` to the host provider, enabling differentiating Linux distributions. This is required to support Debian 12 and other distributions that are moving away from traditional log files in favour of Journald.

---------

Co-authored-by: Mauri de Souza Meneguzzo <mauri870@gmail.com>
(cherry picked from commit d9587c4)

changelog/fragments/1730986549-Add-os_family,-os_platform-and-os_version-to-host-provider.yaml

@@ -0,0 +1,32 @@
+# Kind can be one of:
+# - breaking-change: a change to previously-documented behavior
+# - deprecation: functionality that is being removed in a later release
+# - bug-fix: fixes a problem in a previous version
+# - enhancement: extends functionality but does not break or fix existing behavior
+# - feature: new functionality
+# - known-issue: problems that we are aware of in a given version
+# - security: impacts on the security of a product or a user’s deployment.
+# - upgrade: important information for someone upgrading from a prior version
+# - other: does not fit into any of the other categories
+kind: feature
+
+# Change summary; a 80ish characters long description of the change.
+summary: Add os_family, os_platform and os_version to host provider
+
+# Long description; in case the summary is not enough to describe the change
+# this field accommodate a description without length limits.
+# NOTE: This field will be rendered only for breaking-change and known-issue kinds at the moment.
+#description:
+
+# Affected component; usually one of "elastic-agent", "fleet-server", "filebeat", "metricbeat", "auditbeat", "all", etc.
+component: elastic-agent
+
+# PR URL; optional; the PR number that added the changeset.
+# If not present is automatically filled by the tooling finding the PR where this changelog fragment has been added.
+# NOTE: the tooling supports backports, so it's able to fill the original PR number instead of the backport PR number.
+# Please provide it if you are adding a fragment for a different PR.
+pr: https://github.com/elastic/elastic-agent/pull/5941
+
+# Issue URL; optional; the GitHub issue related to this changeset (either closes or is part of).
+# If not present is automatically filled by the tooling with the issue linked to the PR number.
+issue: https://github.com/elastic/integrations/issues/10797

internal/pkg/composable/providers/host/host.go

@@ -147,6 +147,9 @@ func getHostInfo(log *logger.Logger) func() (map[string]interface{}, error) {
 			"architecture": info.Architecture,
 			"ip":           info.IPs,
 			"mac":          info.MACs,
+			"os_family":    info.OS.Family,
+			"os_platform":  info.OS.Platform,
+			"os_version":   info.OS.Version,
 		}, nil
 	}
 }

internal/pkg/composable/providers/host/host_test.go

@@ -16,6 +16,7 @@ import (
 	ctesting "github.com/elastic/elastic-agent/internal/pkg/composable/testing"
 	"github.com/elastic/elastic-agent/internal/pkg/config"
 	"github.com/elastic/elastic-agent/pkg/core/logger"
+	testlogger "github.com/elastic/elastic-agent/pkg/core/logger/loggertest"
 	"github.com/elastic/elastic-agent/pkg/features"
 )
 
@@ -167,3 +168,21 @@ func returnHostMapping(log *logger.Logger) infoFetcher {
 		return host, nil
 	}
 }
+
+func TestGetHostInfoReturnsSomeKeys(t *testing.T) {
+	l, _ := testlogger.New(t.Name())
+	// this is a simple test to ensure the host provider returns the new keys
+	// needed to add support to Debian 12.
+	osInfo, err := getHostInfo(l)()
+	if err != nil {
+		t.Fatalf("could not get host provider variables: %s", err)
+	}
+
+	expectedKeys := []string{"os_family", "os_platform", "os_version"}
+
+	for _, key := range expectedKeys {
+		if _, exist := osInfo[key]; !exist {
+			t.Errorf("expecting key '%s' from host provider.", key)
+		}
+	}
+}