From 0ef015d3daad258452b0fbf8ac9f3b2659cdc5fa Mon Sep 17 00:00:00 2001
From: Hang Yan <hang.yan@hotmail.com>
Date: Thu, 8 Feb 2018 15:12:16 +0800
Subject: [PATCH] Fix unset env bug for v3 compose

---
 pkg/loader/compose/v3.go                      | 13 ++-
 script/test/cmd/tests.sh                      |  8 ++
 .../fixtures/v3/docker-compose-unset-env.yaml |  8 ++
 .../fixtures/v3/output-unset-env-k8s.json     | 86 +++++++++++++++++++
 4 files changed, 114 insertions(+), 1 deletion(-)
 create mode 100644 script/test/fixtures/v3/docker-compose-unset-env.yaml
 create mode 100644 script/test/fixtures/v3/output-unset-env-k8s.json

diff --git a/pkg/loader/compose/v3.go b/pkg/loader/compose/v3.go
index e9068ba5a..9ba0c928c 100644
--- a/pkg/loader/compose/v3.go
+++ b/pkg/loader/compose/v3.go
@@ -319,8 +319,19 @@ func dockerComposeToKomposeMapping(composeObject *types.Config) (kobject.Kompose
 		// Gather the environment values
 		// DockerCompose uses map[string]*string while we use []string
 		// So let's convert that using this hack
+		// Note: unset env pick up the env value on host if exist
 		for name, value := range composeServiceConfig.Environment {
-			env := kobject.EnvVar{Name: name, Value: *value}
+			var env kobject.EnvVar
+			if value != nil {
+				env = kobject.EnvVar{Name: name, Value: *value}
+			} else {
+				result, ok := os.LookupEnv(name)
+				if ok {
+					env = kobject.EnvVar{Name: name, Value: result}
+				} else {
+					continue
+				}
+			}
 			serviceConfig.Environment = append(serviceConfig.Environment, env)
 		}
 
diff --git a/script/test/cmd/tests.sh b/script/test/cmd/tests.sh
index f6cb3f242..44591008e 100755
--- a/script/test/cmd/tests.sh
+++ b/script/test/cmd/tests.sh
@@ -466,6 +466,14 @@ sed -e "s;%VERSION%;$version;g" -e "s;%CMD%;$cmd;g"  $KOMPOSE_ROOT/script/test/f
 convert::expect_success "kompose convert --stdout -j -f $KOMPOSE_ROOT/script/test/fixtures/v3/docker-compose-env.yaml" "/tmp/output-k8s.json"
 
 
+
+# Test unset environment variables are passed correctly
+export V3_HOST_ENV_TEST_SET_TO_BAR=BAR
+cmd="kompose convert --stdout -j -f $KOMPOSE_ROOT/script/test/fixtures/v3/docker-compose-unset-env.yaml"
+sed -e "s;%VERSION%;$version;g" -e "s;%CMD%;$cmd;g"  $KOMPOSE_ROOT/script/test/fixtures/v3/output-unset-env-k8s.json > /tmp/output-k8s.json
+convert::expect_success "kompose convert --stdout -j -f $KOMPOSE_ROOT/script/test/fixtures/v3/docker-compose-unset-env.yaml" "/tmp/output-k8s.json"
+
+
 # Test environment variables substitution
 cmd="kompose convert --stdout -j -f $KOMPOSE_ROOT/script/test/fixtures/v3/docker-compose-env-subs.yaml"
 sed -e "s;%VERSION%;$version;g" -e "s;%CMD%;$cmd;g"  $KOMPOSE_ROOT/script/test/fixtures/v3/output-env-subs.json > /tmp/output-k8s.json
diff --git a/script/test/fixtures/v3/docker-compose-unset-env.yaml b/script/test/fixtures/v3/docker-compose-unset-env.yaml
new file mode 100644
index 000000000..e04348948
--- /dev/null
+++ b/script/test/fixtures/v3/docker-compose-unset-env.yaml
@@ -0,0 +1,8 @@
+version: '3'
+services:
+  foo:
+    image: foo/bar:latest
+    environment:
+      - BAR
+      - V3_HOST_ENV_TEST_SET_TO_BAR
+      - FOO=foo
diff --git a/script/test/fixtures/v3/output-unset-env-k8s.json b/script/test/fixtures/v3/output-unset-env-k8s.json
new file mode 100644
index 000000000..3a0f20ee3
--- /dev/null
+++ b/script/test/fixtures/v3/output-unset-env-k8s.json
@@ -0,0 +1,86 @@
+{
+  "kind": "List",
+  "apiVersion": "v1",
+  "metadata": {},
+  "items": [
+    {
+      "kind": "Service",
+      "apiVersion": "v1",
+      "metadata": {
+        "name": "foo",
+        "creationTimestamp": null,
+        "labels": {
+          "io.kompose.service": "foo"
+        },
+        "annotations": {
+          "kompose.cmd": "%CMD%",
+          "kompose.version": "%VERSION%"
+        }
+      },
+      "spec": {
+        "ports": [
+          {
+            "name": "headless",
+            "port": 55555,
+            "targetPort": 0
+          }
+        ],
+        "selector": {
+          "io.kompose.service": "foo"
+        },
+        "clusterIP": "None"
+      },
+      "status": {
+        "loadBalancer": {}
+      }
+    },
+    {
+      "kind": "Deployment",
+      "apiVersion": "extensions/v1beta1",
+      "metadata": {
+        "name": "foo",
+        "creationTimestamp": null,
+        "labels": {
+          "io.kompose.service": "foo"
+        },
+        "annotations": {
+          "kompose.cmd": "%CMD%",
+          "kompose.version": "%VERSION%"
+        }
+      },
+      "spec": {
+        "replicas": 1,
+        "template": {
+          "metadata": {
+            "creationTimestamp": null,
+            "labels": {
+              "io.kompose.service": "foo"
+            }
+          },
+          "spec": {
+            "containers": [
+              {
+                "name": "foo",
+                "image": "foo/bar:latest",
+                "env": [
+                  {
+                    "name": "V3_HOST_ENV_TEST_SET_TO_BAR",
+                    "value": "BAR"
+                  },
+                  {
+                    "name": "FOO",
+                    "value": "foo"
+                  }
+                ],
+                "resources": {}
+              }
+            ],
+            "restartPolicy": "Always"
+          }
+        },
+        "strategy": {}
+      },
+      "status": {}
+    }
+  ]
+}