Added CGroupv2 support into Docker Extensions

src/OpenTelemetry.Extensions.Docker/Resources/DockerResourceDetector.cs

@@ -17,6 +17,7 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Text.RegularExpressions;
 using OpenTelemetry.Extensions.Docker.Utils;
 using OpenTelemetry.Resources;
 
@@ -28,24 +29,49 @@ namespace OpenTelemetry.Extensions.Docker.Resources;
 public class DockerResourceDetector : IResourceDetector
 {
     private const string FILEPATH = "/proc/self/cgroup";
+    private const string FILEPATHV2 = "/proc/self/mountinfo";
+    private const string HOSTNAME = "hostname";
+
+    /// <summary>
+    /// CGroup Parse Versions.
+    /// </summary>
+    internal enum ParseMode
+    {
+        /// <summary>
+        /// Represents CGroupV1.
+        /// </summary>
+        V1,
+
+        /// <summary>
+        /// Represents CGroupV2.
+        /// </summary>
+        V2,
+    }
 
     /// <summary>
     /// Detects the resource attributes from Docker.
     /// </summary>
     /// <returns>Resource with key-value pairs of resource attributes.</returns>
     public Resource Detect()
     {
-        return this.BuildResource(FILEPATH);
+        var cGroupBuild = this.BuildResource(FILEPATH, ParseMode.V1);
+        if (cGroupBuild == Resource.Empty)
+        {
+            cGroupBuild = this.BuildResource(FILEPATHV2, ParseMode.V2);
+        }
+
+        return cGroupBuild;
     }
 
     /// <summary>
     /// Builds the resource attributes from Container Id in file path.
     /// </summary>
     /// <param name="path">File path where container id exists.</param>
+    /// <param name="cgroupVersion">CGroup Version of file to parse from.</param>
     /// <returns>Returns Resource with list of key-value pairs of container resource attributes if container id exists else empty resource.</returns>
-    internal Resource BuildResource(string path)
+    internal Resource BuildResource(string path, ParseMode cgroupVersion)
     {
-        var containerId = this.ExtractContainerId(path);
+        var containerId = this.ExtractContainerId(path, cgroupVersion);
 
         if (string.IsNullOrEmpty(containerId))
         {
@@ -58,11 +84,12 @@ internal Resource BuildResource(string path)
     }
 
     /// <summary>
-    /// Extracts Container Id from path.
+    /// Extracts Container Id from path using the cgroupv1 format.
     /// </summary>
     /// <param name="path">cgroup path.</param>
+    /// <param name="cgroupVersion">CGroup Version of file to parse from.</param>
     /// <returns>Container Id, Null if not found or exception being thrown.</returns>
-    private string ExtractContainerId(string path)
+    private string ExtractContainerId(string path, ParseMode cgroupVersion)
     {
         try
         {
@@ -73,7 +100,19 @@ private string ExtractContainerId(string path)
 
             foreach (string line in File.ReadLines(path))
             {
-                string containerId = (!string.IsNullOrEmpty(line)) ? this.GetIdFromLine(line) : null;
+                string containerId = null;
+                if (!string.IsNullOrEmpty(line))
+                {
+                    if (cgroupVersion == ParseMode.V1)
+                    {
+                        containerId = this.GetIdFromLineV1(line);
+                    }
+                    else if (cgroupVersion == ParseMode.V2 && line.Contains(HOSTNAME))
+                    {
+                        containerId = this.GetIdFromLineV2(line);
+                    }
+                }
+
                 if (!string.IsNullOrEmpty(containerId))
                 {
                     return containerId;
@@ -89,11 +128,11 @@ private string ExtractContainerId(string path)
     }
 
     /// <summary>
-    /// Gets the Container Id from the line after removing the prefix and suffix.
+    /// Gets the Container Id from the line after removing the prefix and suffix from the cgroupv1 format.
     /// </summary>
     /// <param name="line">line read from cgroup file.</param>
-    /// <returns>Container Id.</returns>
-    private string GetIdFromLine(string line)
+    /// <returns>Container Id, Null if not found.</returns>
+    private string GetIdFromLineV1(string line)
     {
         // This cgroup output line should have the container id in it
         int lastSlashIndex = line.LastIndexOf('/');
@@ -116,6 +155,28 @@ private string GetIdFromLine(string line)
         return containerId;
     }
 
+    /// <summary>
+    /// Gets the Container Id from the line of the cgroupv2 format.
+    /// </summary>
+    /// <param name="line">line read from cgroup file.</param>
+    /// <returns>Container Id, Null if not found.</returns>
+    private string GetIdFromLineV2(string line)
+    {
+        string containerId = null;
+        var match = Regex.Match(line, @".*/.+/([\w+-.]{64})/.*$");
+        if (match.Success)
+        {
+            containerId = match.Groups[1].Value;
+        }
+
+        if (string.IsNullOrEmpty(containerId) || !EncodingUtils.IsValidHexString(containerId))
+        {
+            return null;
+        }
+
+        return containerId;
+    }
+
     private string RemovePrefixAndSuffixIfneeded(string input, int startIndex, int endIndex)
     {
         startIndex = (startIndex == -1) ? 0 : startIndex + 1;

test/OpenTelemetry.Extensions.Docker.Tests/Resources/DockerResourceDetectorTests.cs

@@ -14,6 +14,7 @@
 // limitations under the License.
 // </copyright>
 
+using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using OpenTelemetry.Extensions.Docker.Resources;
@@ -24,88 +25,168 @@ namespace OpenTelemetry.Extensions.Docker.Tests;
 
 public class DockerResourceDetectorTests
 {
-    // Invalid cgroup line
-    private const string INVALIDCGROUPLINE =
-        "13:name=systemd:/podruntime/docker/kubepods/ac679f8a8319c8cf7d38e1adf263bc08d23zzzz";
-
-    // cgroup line with prefix
-    private const string CGROUPLINEWITHPREFIX =
-        "13:name=systemd:/podruntime/docker/kubepods/crio-e2cc29debdf85dde404998aa128997a819ff";
-
-    // Expected Container Id with prefix removed
-    private const string CONTAINERIDWITHPREFIXREMOVED = "e2cc29debdf85dde404998aa128997a819ff";
-
-    // cgroup line with suffix
-    private const string CGROUPLINEWITHSUFFIX =
-        "13:name=systemd:/podruntime/docker/kubepods/ac679f8a8319c8cf7d38e1adf263bc08d23.aaaa";
-
-    // Expected Container Id with suffix removed
-    private const string CONTAINERIDWITHSUFFIXREMOVED = "ac679f8a8319c8cf7d38e1adf263bc08d23";
-
-    // cgroup line with prefix and suffix
-    private const string CGROUPLINEWITHPREFIXandSUFFIX =
-        "13:name=systemd:/podruntime/docker/kubepods/crio-dc679f8a8319c8cf7d38e1adf263bc08d23.stuff";
-
-    // Expected Container Id with both prefix and suffix removed
-    private const string CONTAINERIDWITHPREFIXANDSUFFIXREMOVED = "dc679f8a8319c8cf7d38e1adf263bc08d23";
-
-    // cgroup line with container Id
-    private const string CGROUPLINE =
-        "13:name=systemd:/pod/d86d75589bf6cc254f3e2cc29debdf85dde404998aa128997a819ff991827356";
-
-    // Expected Container Id
-    private const string CONTAINERID =
-        "d86d75589bf6cc254f3e2cc29debdf85dde404998aa128997a819ff991827356";
+    private readonly List<TestCase> testValidCasesV1 = new()
+    {
+        new TestCase()
+        {
+            Name = "cgroupv1 with prefix",
+            Line = "13:name=systemd:/podruntime/docker/kubepods/crio-e2cc29debdf85dde404998aa128997a819ff",
+            ExpectedContainerId = "e2cc29debdf85dde404998aa128997a819ff",
+            CgroupVersion = DockerResourceDetector.ParseMode.V1,
+        },
+        new TestCase()
+        {
+            Name = "cgroupv1 with suffix",
+            Line = "13:name=systemd:/podruntime/docker/kubepods/ac679f8a8319c8cf7d38e1adf263bc08d23.aaaa",
+            ExpectedContainerId = "ac679f8a8319c8cf7d38e1adf263bc08d23",
+            CgroupVersion = DockerResourceDetector.ParseMode.V1,
+        },
+        new TestCase()
+        {
+            Name = "cgroupv1 with prefix and suffix",
+            Line = "13:name=systemd:/podruntime/docker/kubepods/crio-dc679f8a8319c8cf7d38e1adf263bc08d23.stuff",
+            ExpectedContainerId = "dc679f8a8319c8cf7d38e1adf263bc08d23",
+            CgroupVersion = DockerResourceDetector.ParseMode.V1,
+        },
+        new TestCase()
+        {
+            Name = "cgroupv1 with container Id",
+            Line = "13:name=systemd:/pod/d86d75589bf6cc254f3e2cc29debdf85dde404998aa128997a819ff991827356",
+            ExpectedContainerId = "d86d75589bf6cc254f3e2cc29debdf85dde404998aa128997a819ff991827356",
+            CgroupVersion = DockerResourceDetector.ParseMode.V1,
+        },
+    };
+
+    private readonly List<TestCase> testValidCasesV2 = new()
+    {
+        new TestCase()
+        {
+            Name = "cgroupv2 with container Id",
+            Line = "13:name=systemd:/pod/d86d75589bf6cc254f3e2cc29debdf85dde404998aa128997a819ff991827356/hostname",
+            ExpectedContainerId = "d86d75589bf6cc254f3e2cc29debdf85dde404998aa128997a819ff991827356",
+            CgroupVersion = DockerResourceDetector.ParseMode.V2,
+        },
+        new TestCase()
+        {
+            Name = "cgroupv2 with full line",
+            Line = "473 456 254:1 /docker/containers/dc64b5743252dbaef6e30521c34d6bbd1620c8ce65bdb7bf9e7143b61bb5b183/hostname /etc/hostname rw,relatime - ext4 /dev/vda1 rw",
+            ExpectedContainerId = "dc64b5743252dbaef6e30521c34d6bbd1620c8ce65bdb7bf9e7143b61bb5b183",
+            CgroupVersion = DockerResourceDetector.ParseMode.V2,
+        },
+        new TestCase()
+        {
+            Name = "cgroupv2 with minikube containerd mountinfo",
+            Line = "1537 1517 8:1 /var/lib/containerd/io.containerd.grpc.v1.cri/sandboxes/fb5916a02feca96bdeecd8e062df9e5e51d6617c8214b5e1f3ff9320f4402ae6/hostname /etc/hostname rw,relatime - ext4 /dev/sda1 rw",
+            ExpectedContainerId = "fb5916a02feca96bdeecd8e062df9e5e51d6617c8214b5e1f3ff9320f4402ae6",
+            CgroupVersion = DockerResourceDetector.ParseMode.V2,
+        },
+        new TestCase()
+        {
+            Name = "cgroupv2 with minikube docker mountinfo",
+            Line = "2327 2307 8:1 /var/lib/docker/containers/a1551a1d7e1881d6c18d2c9ec462cab6ad3666825f0adb2098e9d5b198fd7e19/hostname /etc/hostname rw,relatime - ext4 /dev/sda1 rw",
+            ExpectedContainerId = "a1551a1d7e1881d6c18d2c9ec462cab6ad3666825f0adb2098e9d5b198fd7e19",
+            CgroupVersion = DockerResourceDetector.ParseMode.V2,
+        },
+        new TestCase()
+        {
+            Name = "cgroupv2 with minikube docker mountinfo2",
+            Line = "929 920 254:1 /docker/volumes/minikube/_data/lib/docker/containers/0eaa6718003210b6520f7e82d14b4c8d4743057a958a503626240f8d1900bc33/hostname /etc/hostname rw,relatime - ext4 /dev/vda1 rw",
+            ExpectedContainerId = "0eaa6718003210b6520f7e82d14b4c8d4743057a958a503626240f8d1900bc33",
+            CgroupVersion = DockerResourceDetector.ParseMode.V2,
+        },
+        new TestCase()
+        {
+            Name = "cgroupv2 with podman mountinfo",
+            Line = "1096 1088 0:104 /containers/overlay-containers/1a2de27e7157106568f7e081e42a8c14858c02bd9df30d6e352b298178b46809/userdata/hostname /etc/hostname rw,nosuid,nodev,relatime - tmpfs tmpfs rw,size=813800k,nr_inodes=203450,mode=700,uid=1000,gid=1000",
+            ExpectedContainerId = "1a2de27e7157106568f7e081e42a8c14858c02bd9df30d6e352b298178b46809",
+            CgroupVersion = DockerResourceDetector.ParseMode.V2,
+        },
+    };
+
+    private readonly List<TestCase> testInvalidCases = new()
+    {
+        new TestCase()
+        {
+            Name = "Invalid cgroupv1 line",
+            Line = "13:name=systemd:/podruntime/docker/kubepods/ac679f8a8319c8cf7d38e1adf263bc08d23zzzz",
+            CgroupVersion = DockerResourceDetector.ParseMode.V1,
+        },
+        new TestCase()
+        {
+            Name = "Invalid hex cgroupv2 line (contains a z)",
+            Line = "13:name=systemd:/var/lib/containerd/io.containerd.grpc.v1.cri/sandboxes/fb5916a02feca96bdeecd8e062df9e5e51d6617c8214b5e1f3fz9320f4402ae6/hostname",
+            CgroupVersion = DockerResourceDetector.ParseMode.V2,
+        },
+    };
 
     [Fact]
     public void TestValidContainer()
     {
         var dockerResourceDetector = new DockerResourceDetector();
+        var allValidTestCases = this.testValidCasesV1.Concat(this.testValidCasesV2);
 
-        using (TempFile tempFile = new TempFile())
+        foreach (var testCase in allValidTestCases)
         {
-            tempFile.Write(CGROUPLINEWITHPREFIX);
-            Assert.Equal(CONTAINERIDWITHPREFIXREMOVED, this.GetContainerId(dockerResourceDetector.BuildResource(tempFile.FilePath)));
+            using TempFile tempFile = new TempFile();
+            tempFile.Write(testCase.Line);
+            Assert.Equal(
+                testCase.ExpectedContainerId,
+                this.GetContainerId(dockerResourceDetector.BuildResource(tempFile.FilePath, testCase.CgroupVersion)));
         }
+    }
 
-        using (TempFile tempFile = new TempFile())
-        {
-            tempFile.Write(CGROUPLINEWITHSUFFIX);
-            Assert.Equal(CONTAINERIDWITHSUFFIXREMOVED, this.GetContainerId(dockerResourceDetector.BuildResource(tempFile.FilePath)));
-        }
+    [Fact]
+    public void TestInvalidContainer()
+    {
+        var dockerResourceDetector = new DockerResourceDetector();
 
-        using (TempFile tempFile = new TempFile())
+        // Valid in cgroupv1 is not valid in cgroupv2
+        foreach (var testCase in this.testValidCasesV1)
         {
-            tempFile.Write(CGROUPLINEWITHPREFIXandSUFFIX);
-            Assert.Equal(CONTAINERIDWITHPREFIXANDSUFFIXREMOVED, this.GetContainerId(dockerResourceDetector.BuildResource(tempFile.FilePath)));
+            using TempFile tempFile = new TempFile();
+            tempFile.Write(testCase.Line);
+            Assert.Equal(
+                dockerResourceDetector.BuildResource(tempFile.FilePath, DockerResourceDetector.ParseMode.V2),
+                Resource.Empty);
         }
 
-        using (TempFile tempFile = new TempFile())
+        // Valid in cgroupv1 is not valid in cgroupv1
+        foreach (var testCase in this.testValidCasesV2)
         {
-            tempFile.Write(CGROUPLINE);
-            Assert.Equal(CONTAINERID, this.GetContainerId(dockerResourceDetector.BuildResource(tempFile.FilePath)));
+            using TempFile tempFile = new TempFile();
+            tempFile.Write(testCase.Line);
+            Assert.Equal(
+                dockerResourceDetector.BuildResource(tempFile.FilePath, DockerResourceDetector.ParseMode.V1),
+                Resource.Empty);
         }
-    }
 
-    [Fact]
-    public void TestInvalidContainer()
-    {
-        var dockerResourceDetector = new DockerResourceDetector();
-
-        // test invalid containerId (non-hex)
-        using (TempFile tempFile = new TempFile())
+        // test invalid cases
+        foreach (var testCase in this.testInvalidCases)
         {
-            tempFile.Write(INVALIDCGROUPLINE);
-            Assert.Equal(dockerResourceDetector.BuildResource(tempFile.FilePath), Resource.Empty);
+            using TempFile tempFile = new TempFile();
+            tempFile.Write(testCase.Line);
+            Assert.Equal(dockerResourceDetector.BuildResource(tempFile.FilePath, testCase.CgroupVersion), Resource.Empty);
         }
 
         // test invalid file
-        Assert.Equal(dockerResourceDetector.BuildResource(Path.GetTempPath()), Resource.Empty);
+        Assert.Equal(dockerResourceDetector.BuildResource(Path.GetTempPath(), DockerResourceDetector.ParseMode.V1), Resource.Empty);
+        Assert.Equal(dockerResourceDetector.BuildResource(Path.GetTempPath(), DockerResourceDetector.ParseMode.V2), Resource.Empty);
     }
 
     private string GetContainerId(Resource resource)
     {
         var resourceAttributes = resource.Attributes.ToDictionary(x => x.Key, x => x.Value);
         return resourceAttributes[DockerSemanticConventions.AttributeContainerID]?.ToString();
     }
+
+    private class TestCase
+    {
+        public string Name { get; set; }
+
+        public string Line { get; set; }
+
+        public string ExpectedContainerId { get; set; }
+
+        public DockerResourceDetector.ParseMode CgroupVersion { get; set; }
+    }
 }