added a configuration file hack to allow to read environment variables

cmd/cmd.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"encoding/json"
 	"flag"
 	"fmt"
@@ -94,10 +95,10 @@ func readConf() {
 	}
 
 	if node, ok := root["driver"].(string); ok {
-		driver = node
+		driver = subEnvVars(node)
 	}
 	if node, ok := root["source"].(string); ok {
-		source = node
+		source = subEnvVars(node)
 	}
 }
 
@@ -300,3 +301,51 @@ func copyFile(dst, src string) (int64, error) {
 	defer df.Close()
 	return io.Copy(df, sf)
 }
+
+
+const (
+	WAITING_FOR_START    = 0
+	WAITING_FOR_MUSTACHE = 1
+	WAITING_FOR_END      = 2
+)
+func subEnvVars(in string) string {
+	state := WAITING_FOR_START
+	var collected *bytes.Buffer
+
+	result := new(bytes.Buffer)
+
+	for _, c := range in {
+		switch state {
+
+		case WAITING_FOR_START:
+			switch c {
+			case '$':
+				state = WAITING_FOR_MUSTACHE
+			default: 
+				result.WriteRune(c)
+			}
+
+		case WAITING_FOR_MUSTACHE:
+			switch c {
+			case '{':
+				collected = new(bytes.Buffer)
+				state = WAITING_FOR_END
+			default:
+				result.WriteRune('$')
+				result.WriteRune(c)
+				state = WAITING_FOR_START
+			}
+
+		case WAITING_FOR_END:
+			switch c {
+			case '}':
+				v := strings.ToUpper(collected.String())
+				result.WriteString(os.Getenv(v))
+				state = WAITING_FOR_START
+			default:
+				collected.WriteRune(c)
+			}
+		}
+	}
+	return result.String()
+}

cmd/cmd_test.go

@@ -0,0 +1,27 @@
+package main
+
+import (
+	"os"
+	"testing"
+)
+
+func TestEnvVarReplacement(t *testing.T) {
+	if os.Setenv("FOO", "yakshaving") != nil {
+		t.Fatalf("can't set environment var for test (foo)")
+	}
+	if os.Setenv("BAR", "fleazil") != nil {
+		t.Fatalf("can't set environment var for test (bar)")
+	}
+	if subEnvVars("${foo}") != "yakshaving" {
+		t.Errorf("failed simple variable substitution")
+	}
+	if subEnvVars("${foo}x${bar}") != "yakshavingxfleazil" {
+		t.Errorf("failed variable substitution combined with concat test")
+	}
+	if subEnvVars("$$x${bar}") != "$$xfleazil" {
+		t.Errorf("failed variable substitution combined with concat test")
+	}
+	if subEnvVars("{$}x${bar}$foo") != "{$}xfleazil$foo" {
+		t.Errorf("failed variable substitution combined with concat test")
+	}
+}

dialects_test.go

@@ -16,7 +16,7 @@ import (
 
 import (
 	_ "github.com/lib/pq"
-	_ "github.com/ziutek/mymysql/godrv"
+	//"github.com/ziutek/mymysql/godrv"
 )
 
 var toRun = []dialectInfo{

util.go

@@ -57,3 +57,4 @@ func columnsMarkersAndValuesForModel(dialect Dialect, model *Model, markerPos *i
 	}
 	return columns, markers, values
 }
+