Remove tfexec, allow TF_ environment vars and log them (#2264)

* Remove tfexec, allow TF_ environment vars and log them

Signed-off-by: Spike Curtis <spike@coder.com>

* fixup: commented code, long lines

Signed-off-by: Spike Curtis <spike@coder.com>

* rename executor methods to remove get

Signed-off-by: Spike Curtis <spike@coder.com>

* don't log terraform environment variables we don't know are safe

Signed-off-by: Spike Curtis <spike@coder.com>

* Disable linting of fake secret

Signed-off-by: Spike Curtis <spike@coder.com>

* drop parse support and move logger into terraform package

Signed-off-by: Spike Curtis <spike@coder.com>

* disable testpackage linter on internal package test

Signed-off-by: Spike Curtis <spike@coder.com>

provisioner/terraform/executor_test.go

@@ -0,0 +1,63 @@
+// nolint:testpackage
+package terraform
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"golang.org/x/xerrors"
+
+	"github.com/coder/coder/provisionersdk/proto"
+)
+
+type mockLogger struct {
+	logs   []*proto.Log
+	retVal error
+}
+
+func (m *mockLogger) Log(l *proto.Log) error {
+	m.logs = append(m.logs, l)
+	return m.retVal
+}
+
+func TestLogWriter_Mainline(t *testing.T) {
+	t.Parallel()
+
+	logr := &mockLogger{retVal: nil}
+	writer, doneLogging := logWriter(logr, proto.LogLevel_INFO)
+
+	_, err := writer.Write([]byte(`Sitting in an English garden
+Waiting for the sun
+If the sun don't come you get a tan
+From standing in the English rain`))
+	require.NoError(t, err)
+	err = writer.Close()
+	require.NoError(t, err)
+	<-doneLogging
+
+	expected := []*proto.Log{
+		{Level: proto.LogLevel_INFO, Output: "Sitting in an English garden"},
+		{Level: proto.LogLevel_INFO, Output: "Waiting for the sun"},
+		{Level: proto.LogLevel_INFO, Output: "If the sun don't come you get a tan"},
+		{Level: proto.LogLevel_INFO, Output: "From standing in the English rain"},
+	}
+	require.Equal(t, logr.logs, expected)
+}
+
+func TestLogWriter_SendError(t *testing.T) {
+	t.Parallel()
+
+	logr := &mockLogger{retVal: xerrors.New("Goo goo g'joob")}
+	writer, doneLogging := logWriter(logr, proto.LogLevel_INFO)
+
+	_, err := writer.Write([]byte(`Sitting in an English garden
+Waiting for the sun
+If the sun don't come you get a tan
+From standing in the English rain`))
+	require.NoError(t, err)
+	err = writer.Close()
+	require.NoError(t, err)
+	<-doneLogging
+	expected := []*proto.Log{{Level: proto.LogLevel_INFO, Output: "Sitting in an English garden"}}
+	require.Equal(t, logr.logs, expected)
+}