updates Habitat plugin to guard for hab binary existing

Signed-off-by: Collin McNeese <cmcneese@chef.io>

2 files changed, 10 insertions, 3 deletions

diff --git a/lib/ohai/plugins/habitat.rb b/lib/ohai/plugins/habitat.rb
index a9e7ff2d..26bbddef 100644
--- a/lib/ohai/plugins/habitat.rb
+++ b/lib/ohai/plugins/habitat.rb
@@ -18,16 +18,20 @@
 Ohai.plugin(:Habitat) do
   provides "habitat"
 
+  def habitat_exists?
+    which("habitat")
+  end
+
   def fetch_habitat_version
     shell_out(["hab"], ["-V"]).stdout.gsub(/hab\s*/, "").strip
   rescue Ohai::Exceptions::Exec
-    logger.trace("Plugin Habitat: No detected version of hab binary found in PATH, skipping collection.")
+    logger.trace("Plugin Habitat: Unable to determine the installed version of Habitat, skipping collection.")
   end
 
   def fetch_habitat_packages
     shell_out(["hab", "pkg", "list", "--all"]).stdout.split.sort.select { |pkg| pkg.match?(%r{.*/.*/.*/.*}) }
   rescue Ohai::Exceptions::Exec
-    logger.trace("Plugin Habitat: No detected version of hab binary found in PATH, skipping collection.")
+    logger.trace("Plugin Habitat: Unable to determine the installed Habitat packages, skipping collection.")
   end
 
   def load_habitat_service_via_cli(status_stdout)
@@ -54,10 +58,12 @@ Ohai.plugin(:Habitat) do
     services_shell_out = shell_out(%w{hab svc status}).stdout
     load_habitat_service_via_cli(services_shell_out) if services_shell_out
   rescue Ohai::Exceptions::Exec
-    logger.trace("Plugin Habitat: No detected version of hab binary found in PATH, skipping collection.")
+    logger.trace("Plugin Habitat: Unable to determine the installed Habitat services, skipping collection.")
   end
 
   collect_data(:default) do
+    return unless habitat_exists?
+
     habitat Mash.new
     habitat["version"] = fetch_habitat_version
     habitat["packages"] = fetch_habitat_packages
diff --git a/spec/unit/plugins/habitat_spec.rb b/spec/unit/plugins/habitat_spec.rb
index 175ae3b8..183a2174 100644
--- a/spec/unit/plugins/habitat_spec.rb
+++ b/spec/unit/plugins/habitat_spec.rb
@@ -34,6 +34,7 @@ describe "plugin habitat" do
     allow(plugin).to receive(:shell_out).with(["hab", "pkg", "list",
                                                "--all"]).and_return(mock_shell_out(0, pkg_result, ""))
     allow(plugin).to receive(:shell_out).with(%w{hab svc status}).and_return(mock_shell_out(0, svc_result, ""))
+    allow(plugin).to receive(:habitat_exists?).and_return(true)
     plugin.run
   end