Docker host detection and information

lib/ohai/plugins/darwin/virtualization.rb

@@ -37,10 +37,20 @@ def fusion_exists?
     ::File.exist?("/Applications/VMware\ Fusion.app/")
   end
 
+  def docker_exists?
+    which("docker")
+  end
+
   collect_data(:darwin) do
     virtualization Mash.new unless virtualization
     virtualization[:systems] = Mash.new unless virtualization[:systems]
 
+    if docker_exists?
+      virtualization[:system] = "docker"
+      virtualization[:role] = "host"
+      virtualization[:systems][:docker] = "host"
+    end
+
     if vboxmanage_exists?
       virtualization[:system] = "vbox"
       virtualization[:role] = "host"

lib/ohai/plugins/docker.rb

@@ -0,0 +1,57 @@
+#
+# Copyright:: 2018 Chef Software, Inc.
+# License:: Apache License, Version 2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+Ohai.plugin(:Docker) do
+  require "json"
+
+  provides "docker"
+  depends "virtualization"
+
+  def docker_info_json
+    so = shell_out("docker info --format '{{json .}}'")
+    if so.exitstatus == 0
+      return JSON.parse(so.stdout)
+    end
+  rescue Ohai::Exceptions::Exec
+    Ohai::Log.debug('Plugin Docker: Could not shell_out "docker info --format \'{{json .}}\'". Skipping plugin')
+  end
+
+  def docker_ohai_data(shellout_data)
+    docker Mash.new
+    docker[:version_string] = shellout_data["ServerVersion"]
+    docker[:version] = shellout_data["ServerVersion"].split("-")[0] if shellout_data["ServerVersion"] # guard this so missing data doesn't fail the run
+    docker[:runtimes] = shellout_data["Runtimes"]
+    docker[:root_dir] = shellout_data["DockerRootDir"]
+    docker[:containers] = {}
+    docker[:containers][:total] = shellout_data["Containers"]
+    docker[:containers][:running] = shellout_data["ContainersRunning"]
+    docker[:containers][:paused] = shellout_data["ContainersPaused"]
+    docker[:containers][:stopped] = shellout_data["ContainersStopped"]
+    docker[:plugins] = shellout_data["Plugins"]
+    docker[:networking] = {}
+    docker[:networking][:ipv4_forwarding] = shellout_data["IPv4Forwarding"]
+    docker[:networking][:bridge_nf_iptables] = shellout_data["BridgeNfIptables"]
+    docker[:networking][:bridge_nf_ipv6_iptables] = shellout_data["BridgeNfIp6tables"]
+    docker[:swarm] = shellout_data["Swarm"]
+  end
+
+  collect_data do
+    if virtualization[:systems][:docker]
+      docker_ohai_data(docker_info_json)
+    end
+  end
+end

lib/ohai/plugins/linux/virtualization.rb

@@ -29,12 +29,27 @@ def nova_exists?
     which("nova")
   end
 
+  def docker_exists?
+    which("docker")
+  end
+
   collect_data(:linux) do
     virtualization Mash.new unless virtualization
     virtualization[:systems] = Mash.new unless virtualization[:systems]
 
-    ## Xen
-    # /proc/xen is an empty dir for EL6 + Linode Guests + Paravirt EC2 instances
+    # Docker hosts
+    if docker_exists?
+      virtualization[:system] = "docker"
+      virtualization[:role] = "host"
+      virtualization[:systems][:docker] = "host"
+    end
+
+    # Xen Notes:
+    # - /proc/xen is an empty dir for EL6 + Linode Guests + Paravirt EC2 instances
+    # - cpuid of guests, if we could get it, would also be a clue
+    # - may be able to determine if under paravirt from /dev/xen/evtchn (See OHAI-253)
+    # - Additional edge cases likely should not change the above assumptions
+    #   but rather be additive - btm
     if File.exist?("/proc/xen")
       virtualization[:system] = "xen"
       # Assume guest
@@ -51,12 +66,6 @@ def nova_exists?
       end
     end
 
-    # Xen Notes:
-    # - cpuid of guests, if we could get it, would also be a clue
-    # - may be able to determine if under paravirt from /dev/xen/evtchn (See OHAI-253)
-    # - Additional edge cases likely should not change the above assumptions
-    #   but rather be additive - btm
-
     # Detect Virtualbox from kernel module
     if File.exist?("/proc/modules")
       modules = File.read("/proc/modules")

spec/unit/plugins/darwin/virtualization_spec.rb

@@ -29,6 +29,7 @@
     allow(plugin).to receive(:ioreg_exists?).and_return(false)
     allow(plugin).to receive(:vboxmanage_exists?).and_return(false)
     allow(plugin).to receive(:fusion_exists?).and_return(false)
+    allow(plugin).to receive(:docker_exists?).and_return(false)
   end
 
   describe "when detecting OS X virtualization" do
@@ -37,6 +38,14 @@
       expect(plugin[:virtualization]).to eq({ "systems" => {} })
     end
 
+    it "should set docker host if docker exists" do
+      allow(plugin).to receive(:docker_exists?).and_return(true)
+      plugin.run
+      expect(plugin[:virtualization][:system]).to eq("docker")
+      expect(plugin[:virtualization][:role]).to eq("host")
+      expect(plugin[:virtualization][:systems][:docker]).to eq("host")
+    end
+
     it "should set vmware host if /Applications/VMware\ Fusion.app exists" do
       allow(plugin).to receive(:fusion_exists?).and_return(true)
       plugin.run

spec/unit/plugins/docker_spec.rb

@@ -0,0 +1,100 @@
+#
+# Copyright:: 2018 Chef Software, Inc.
+# License:: Apache License, Version 2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require_relative "../../spec_helper.rb"
+
+docker_output = <<EOF
+{"ID":"KZET:VDFN:2V2G:JS5Z:HAKO:SOGI:AFSZ:HDMT:GVEM:V2NT:DUSW:J3Z6","Containers":11,"ContainersRunning":0,"ContainersPaused":0,"ContainersStopped":11,"Images":30,"Driver":"overlay2","DriverStatus":[["Backing Filesystem","extfs"],["Supports d_type","true"],["Native Overlay Diff","true"]],"SystemStatus":null,"Plugins":{"Volume":["local"],"Network":["bridge","host","ipvlan","macvlan","null","overlay"],"Authorization":null,"Log":["awslogs","fluentd","gcplogs","gelf","journald","json-file","logentries","splunk","syslog"]},"MemoryLimit":true,"SwapLimit":true,"KernelMemory":true,"CpuCfsPeriod":true,"CpuCfsQuota":true,"CPUShares":true,"CPUSet":true,"IPv4Forwarding":true,"BridgeNfIptables":true,"BridgeNfIp6tables":true,"Debug":true,"NFd":21,"OomKillDisable":true,"NGoroutines":39,"SystemTime":"2018-02-15T19:12:40.214106068Z","LoggingDriver":"json-file","CgroupDriver":"cgroupfs","NEventsListener":2,"KernelVersion":"4.9.60-linuxkit-aufs","OperatingSystem":"Docker for Mac","OSType":"linux","Architecture":"x86_64","IndexServerAddress":"https://index.docker.io/v1/","RegistryConfig":{"AllowNondistributableArtifactsCIDRs":[],"AllowNondistributableArtifactsHostnames":[],"InsecureRegistryCIDRs":["127.0.0.0/8"],"IndexConfigs":{"docker.io":{"Name":"docker.io","Mirrors":[],"Secure":true,"Official":true}},"Mirrors":[]},"NCPU":4,"MemTotal":2095816704,"GenericResources":null,"DockerRootDir":"/var/lib/docker","HttpProxy":"docker.for.mac.http.internal:3128","HttpsProxy":"docker.for.mac.http.internal:3129","NoProxy":"","Name":"linuxkit-025000000001","Labels":[],"ExperimentalBuild":true,"ServerVersion":"17.12.0-ce","ClusterStore":"","ClusterAdvertise":"","Runtimes":{"runc":{"path":"docker-runc"}},"DefaultRuntime":"runc","Swarm":{"NodeID":"","NodeAddr":"","LocalNodeState":"inactive","ControlAvailable":false,"Error":"","RemoteManagers":null},"LiveRestoreEnabled":false,"Isolation":"","InitBinary":"docker-init","ContainerdCommit":{"ID":"89623f28b87a6004d4b785663257362d1658a729","Expected":"89623f28b87a6004d4b785663257362d1658a729"},"RuncCommit":{"ID":"b2567b37d7b75eb4cf325b77297b140ea686ce8f","Expected":"b2567b37d7b75eb4cf325b77297b140ea686ce8f"},"InitCommit":{"ID":"949e6fa","Expected":"949e6fa"},"SecurityOptions":["name=seccomp,profile=default"]}
+EOF
+
+expected_output = {
+  "version_string" => "17.12.0-ce",
+  "version" => "17.12.0",
+  "runtimes" => {
+    "runc" => {
+      "path" => "docker-runc",
+    },
+  },
+  "root_dir" => "/var/lib/docker",
+  "containers" => {
+    "total" => 11,
+    "running" => 0,
+    "paused" => 0,
+    "stopped" => 11,
+  },
+  "plugins" => {
+    "Volume" => [
+      "local",
+    ],
+    "Network" => %w{
+bridge
+host
+ipvlan
+macvlan
+null
+overlay},
+    "Authorization" => nil,
+    "Log" => [
+      "awslogs",
+      "fluentd",
+      "gcplogs",
+      "gelf",
+      "journald",
+      "json-file",
+      "logentries",
+      "splunk",
+      "syslog",
+    ],
+  },
+  "networking" => {
+    "ipv4_forwarding" => true,
+    "bridge_nf_iptables" => true,
+    "bridge_nf_ipv6_iptables" => true,
+  },
+  "swarm" => {
+    "NodeID" => "",
+    "NodeAddr" => "",
+    "LocalNodeState" => "inactive",
+    "ControlAvailable" => false,
+    "Error" => "",
+    "RemoteManagers" => nil,
+  },
+}
+
+describe Ohai::System, "plugin docker" do
+  let(:plugin) { get_plugin("docker") }
+
+  context "if the machine does not have docker installed" do
+    it "should not create a docker attribute" do
+      plugin[:virtualization] = Mash.new
+      plugin[:virtualization][:systems] = Mash.new
+      plugin.run
+      expect(plugin).not_to have_key(:docker)
+    end
+  end
+
+  context "if the machine has docker installed" do
+    it "should create a docker attribute with correct data" do
+      plugin[:virtualization] = Mash.new
+      plugin[:virtualization][:systems] = Mash.new
+      plugin[:virtualization][:systems][:docker] = "host"
+      allow(plugin).to receive(:shell_out).with("docker info --format '{{json .}}'").and_return(mock_shell_out(0, docker_output, ""))
+      plugin.run
+      expect(plugin).to have_key(:docker)
+      expect(plugin[:docker]).to eq(expected_output)
+    end
+  end
+end

spec/unit/plugins/linux/virtualization_spec.rb

@@ -45,6 +45,7 @@
     # default the which wrappers to nil
     allow(plugin).to receive(:which).with("lxc-version").and_return(nil)
     allow(plugin).to receive(:which).with("lxc-start").and_return(nil)
+    allow(plugin).to receive(:which).with("docker").and_return(nil)
     allow(plugin).to receive(:nova_exists?).and_return(false)
   end
 
@@ -85,6 +86,16 @@
     end
   end
 
+  describe "when we are checking for docker" do
+    it "sets docker host if docker binary exists" do
+      allow(plugin).to receive(:which).with("docker").and_return(true)
+      plugin.run
+      expect(plugin[:virtualization][:system]).to eq("docker")
+      expect(plugin[:virtualization][:role]).to eq("host")
+      expect(plugin[:virtualization][:systems][:docker]).to eq("host")
+    end
+  end
+
   describe "when we are checking for openstack" do
     it "sets openstack host if nova binary exists" do
       allow(plugin).to receive(:nova_exists?).and_return("/usr/bin/nova")