[processor/resourcedetection] Add host.ip addresses detection (#24450)

**Description:** 

Adds detection for `host.ip`.

Relates to open-telemetry/semantic-conventions/pull/203

Fixes #24765

Author: mx-psi

.chloggen/mx-psi_host.ip-ref-impl.yaml

@@ -0,0 +1,20 @@
+# Use this changelog template to create an entry for release notes.
+# If your change doesn't affect end users, such as a test fix or a tooling change,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: resourcedetectionprocessor
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add detection of host.ip to system detector.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [24450]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

internal/metadataproviders/system/metadata.go

@@ -63,6 +63,9 @@ type Provider interface {
 
 	// HostArch returns the host architecture
 	HostArch() (string, error)
+
+	// HostIPs returns the host's IP interfaces
+	HostIPs() ([]net.IP, error)
 }
 
 type systemMetadataProvider struct {
@@ -159,3 +162,37 @@ func (p systemMetadataProvider) OSDescription(ctx context.Context) (string, erro
 func (systemMetadataProvider) HostArch() (string, error) {
 	return internal.GOARCHtoHostArch(runtime.GOARCH), nil
 }
+
+func (p systemMetadataProvider) HostIPs() (ips []net.IP, err error) {
+	ifaces, err := net.Interfaces()
+	if err != nil {
+		return nil, err
+	}
+
+	for _, iface := range ifaces {
+		// skip if the interface is down or is a loopback interface
+		if iface.Flags&net.FlagUp == 0 || iface.Flags&net.FlagLoopback != 0 {
+			continue
+		}
+
+		addrs, errAddr := iface.Addrs()
+		if errAddr != nil {
+			return nil, fmt.Errorf("failed to get addresses for interface %v: %w", iface, errAddr)
+		}
+		for _, addr := range addrs {
+			ip, _, parseErr := net.ParseCIDR(addr.String())
+			if parseErr != nil {
+				return nil, fmt.Errorf("failed to parse address %q from interface %v: %w", addr, iface, parseErr)
+			}
+
+			if ip.IsLoopback() {
+				// skip loopback IPs
+				continue
+			}
+
+			ips = append(ips, ip)
+		}
+
+	}
+	return ips, err
+}

processor/resourcedetectionprocessor/README.md

@@ -48,6 +48,7 @@ Queries the host machine to retrieve the following resource attributes:
     * host.arch
     * host.name
     * host.id
+    * host.ip
     * host.cpu.vendor.id
     * host.cpu.family
     * host.cpu.model.id

processor/resourcedetectionprocessor/internal/system/internal/metadata/generated_config.go

@@ -17,6 +17,8 @@ all_set:
       enabled: true
     host.id:
       enabled: true
+    host.ip:
+      enabled: true
     host.name:
       enabled: true
     os.description:
@@ -41,6 +43,8 @@ none_set:
       enabled: false
     host.id:
       enabled: false
+    host.ip:
+      enabled: false
     host.name:
       enabled: false
     os.description:

processor/resourcedetectionprocessor/internal/system/internal/metadata/generated_config_test.go

@@ -23,6 +23,10 @@ resource_attributes:
     description: The host.arch
     type: string
     enabled: false
+  host.ip:
+    description: IP addresses for the host
+    type: slice
+    enabled: false
   host.cpu.vendor.id:
     description: The host.cpu.vendor.id
     type: string

processor/resourcedetectionprocessor/internal/system/internal/metadata/generated_resource.go

@@ -83,6 +83,17 @@ func (d *Detector) Detect(ctx context.Context) (resource pcommon.Resource, schem
 		return pcommon.NewResource(), "", fmt.Errorf("failed getting host architecture: %w", err)
 	}
 
+	var hostIPAttribute []any
+	if d.cfg.ResourceAttributes.HostIP.Enabled {
+		hostIPs, errIPs := d.provider.HostIPs()
+		if errIPs != nil {
+			return pcommon.NewResource(), "", fmt.Errorf("failed getting host IP addresses: %w", errIPs)
+		}
+		for _, ip := range hostIPs {
+			hostIPAttribute = append(hostIPAttribute, ip.String())
+		}
+	}
+
 	osDescription, err := d.provider.OSDescription(ctx)
 	if err != nil {
 		return pcommon.NewResource(), "", fmt.Errorf("failed getting OS description: %w", err)
@@ -107,6 +118,7 @@ func (d *Detector) Detect(ctx context.Context) (resource pcommon.Resource, schem
 				}
 			}
 			d.rb.SetHostArch(hostArch)
+			d.rb.SetHostIP(hostIPAttribute)
 			d.rb.SetOsDescription(osDescription)
 			if len(cpuInfo) > 0 {
 				err = setHostCPUInfo(d, cpuInfo[0])