Merge pull request #266 from glours/env-var-priority

Author: ndeloof

cli/options.go

@@ -226,22 +226,18 @@ func WithDotEnv(o *ProjectOptions) error {
 	}
 	defer file.Close()
 
-	notInEnvSet := make(map[string]interface{})
 	env, err := dotenv.ParseWithLookup(file, func(k string) (string, bool) {
 		v, ok := o.Environment[k]
 		if !ok {
-			notInEnvSet[k] = nil
-			return "", true
+
+			return "", false
 		}
 		return v, true
 	})
 	if err != nil {
 		return err
 	}
 	for k, v := range env {
-		if _, ok := notInEnvSet[k]; ok {
-			continue
-		}
 		if _, set := o.Environment[k]; set {
 			continue
 		}

dotenv/godotenv_test.go

@@ -612,3 +612,34 @@ func TestExpendingEnvironmentWithLookup(t *testing.T) {
 		t.Errorf("Expected '%v' to parse as '%v' => '%v', got '%v' => '%v' instead", rawEnvLine, key, expectedValue, key, value)
 	}
 }
+
+func TestSubstitutionsWithShellEnvPrecedence(t *testing.T) {
+	os.Clearenv()
+	const envKey = "OPTION_A"
+	const envVal = "5"
+	os.Setenv(envKey, envVal)
+	defer os.Unsetenv(envKey)
+
+	envFileName := "fixtures/substitutions.env"
+	expectedValues := map[string]string{
+		"OPTION_A": "5",
+		"OPTION_B": "5",
+		"OPTION_C": "5",
+		"OPTION_D": "55",
+		"OPTION_E": "",
+	}
+
+	envMap, err := ReadWithLookup(os.LookupEnv, envFileName)
+	if err != nil {
+		t.Error("Error reading file")
+	}
+	if len(envMap) != len(expectedValues) {
+		t.Error("Didn't get the right size map back")
+	}
+
+	for key, value := range expectedValues {
+		if envMap[key] != value {
+			t.Errorf("Read got one of the keys wrong, [%q]->%q", key, envMap[key])
+		}
+	}
+}

dotenv/parser.go

@@ -18,6 +18,9 @@ const (
 
 func parseBytes(src []byte, out map[string]string, lookupFn LookupFn) error {
 	cutset := src
+	if lookupFn == nil {
+		lookupFn = noLookupFn
+	}
 	for {
 		cutset = getStatementStart(cutset)
 		if cutset == nil {
@@ -34,9 +37,6 @@ func parseBytes(src []byte, out map[string]string, lookupFn LookupFn) error {
 		}
 
 		if inherited {
-			if lookupFn == nil {
-				lookupFn = noLookupFn
-			}
 
 			value, ok := lookupFn(key)
 			if ok {
@@ -50,6 +50,9 @@ func parseBytes(src []byte, out map[string]string, lookupFn LookupFn) error {
 		if err != nil {
 			return err
 		}
+		if lookUpValue, ok := lookupFn(key); ok {
+			value = lookUpValue
+		}
 
 		out[key] = value
 		cutset = left

loader/full-struct_test.go

@@ -165,7 +165,7 @@ func services(workingDir, homeDir string) []types.ServiceConfig {
 			Entrypoint: []string{"/code/entrypoint.sh", "-p", "3000"},
 			Environment: map[string]*string{
 				"FOO": strPtr("foo_from_env_file"),
-				"BAR": strPtr("bar_from_env_file_2"),
+				"BAR": strPtr("this is a secret"),
 				"BAZ": strPtr("baz_from_service_def"),
 				"QUX": strPtr("qux_from_environment"),
 			},
@@ -689,7 +689,7 @@ services:
     - -p
     - "3000"
     environment:
-      BAR: bar_from_env_file_2
+      BAR: this is a secret
       BAZ: baz_from_service_def
       FOO: foo_from_env_file
       QUX: qux_from_environment
@@ -1259,7 +1259,7 @@ func fullExampleJSON(workingDir, homeDir string) string {
         "3000"
       ],
       "environment": {
-        "BAR": "bar_from_env_file_2",
+        "BAR": "this is a secret",
         "BAZ": "baz_from_service_def",
         "FOO": "foo_from_env_file",
         "QUX": "qux_from_environment"

loader/loader_test.go

@@ -1833,8 +1833,10 @@ func TestLoadServiceWithEnvFile(t *testing.T) {
 		"env_file": file.Name(),
 	}
 	s, err := LoadService("Test Name", m, ".", func(s string) (string, bool) {
-		assert.Equal(t, "TEST", s)
-		return "YES", true
+		if s == "TEST" {
+			return "YES", true
+		}
+		return "", false
 	}, true, false)
 	assert.NilError(t, err)
 	assert.Equal(t, "YES", *s.Environment["HALLO"])