Support passthrough of system env for local-exec provisioner

builtin/provisioners/local-exec/resource_provisioner.go

@@ -7,6 +7,7 @@ import (
 	"os"
 	"os/exec"
 	"runtime"
+	"strings"
 
 	"github.com/armon/circbuf"
 	"github.com/hashicorp/terraform/helper/schema"
@@ -41,6 +42,10 @@ func Provisioner() terraform.ResourceProvisioner {
 				Type:     schema.TypeMap,
 				Optional: true,
 			},
+			"system_environment": &schema.Schema{
+				Type:     schema.TypeBool,
+				Optional: true,
+			},
 		},
 
 		ApplyFunc: applyFn,
@@ -57,7 +62,18 @@ func applyFn(ctx context.Context) error {
 	}
 
 	// Execute the command with env
-	environment := data.Get("environment").(map[string]interface{})
+	environment := make(map[string]interface{})
+	// Start with the system env (if desired)
+	if data.Get("system_environment").(bool) {
+		for _, e := range os.Environ() {
+			pair := strings.SplitN(e, "=", 2)
+			environment[pair[0]] = pair[1]
+		}
+	}
+	// Apply the explicitly specified environment
+	for k, v := range data.Get("environment").(map[string]interface{}) {
+		environment[k] = v
+	}
 
 	var env []string
 	for k := range environment {

builtin/provisioners/local-exec/resource_provisioner_test.go

@@ -192,3 +192,37 @@ func TestResourceProvider_ApplyCustomEnv(t *testing.T) {
 		t.Errorf("wrong output\ngot:  %s\nwant: %s", got, want)
 	}
 }
+
+func TestResourceProvider_ApplySystemEnv(t *testing.T) {
+	// Preserve original system env values (if any)
+	origFoo := os.Getenv("FOO")
+	defer os.Setenv("FOO", origFoo)
+	origBam := os.Getenv("BAM")
+	defer os.Setenv("FOO", origBam)
+
+	os.Setenv("FOO", "SystemFOO")
+	os.Setenv("BAM", "SystemBAM")
+
+	c := testConfig(t, map[string]interface{}{
+		"command":    "echo $FOO $BAR $BAZ $BAM",
+		"system_env": true,
+		"environment": map[string]interface{}{
+			"FOO": "BAR",
+			"BAR": 1,
+			"BAZ": "true",
+		},
+	})
+
+	output := new(terraform.MockUIOutput)
+	p := Provisioner()
+
+	if err := p.Apply(output, nil, c); err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	got := strings.TrimSpace(output.OutputMessage)
+	want := "BAR 1 true SystemBAM"
+	if got != want {
+		t.Errorf("wrong output\ngot:  %s\nwant: %s", got, want)
+	}
+}

website/docs/provisioners/local-exec.html.markdown

@@ -58,6 +58,11 @@ The following arguments are supported:
 * `environment` - (Optional) block of key value pairs representing the
   environment of the executed command. inherits the current process environment.
 
+* `system_environment` - (Optional) If true, the environment of the terraform 
+   process will be passed through to the executed command. Variables explicitly specified
+   in `environment` will take precedence over any variables inherited from the system
+   environment. 
+
 ### Interpreter Examples
 
 ```hcl