Shadow the password on cache and session config on admin panel (#7300)

* shadow the password on cache and session config on admin panel

* add shadow password of mysql/postgres/couchbase

* fix log import

routers/admin/admin_test.go

@@ -0,0 +1,69 @@
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package admin
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestShadowPassword(t *testing.T) {
+	var kases = []struct {
+		Provider string
+		CfgItem  string
+		Result   string
+	}{
+		{
+			Provider: "redis",
+			CfgItem:  "network=tcp,addr=:6379,password=gitea,db=0,pool_size=100,idle_timeout=180",
+			Result:   "network=tcp,addr=:6379,password=******,db=0,pool_size=100,idle_timeout=180",
+		},
+		{
+			Provider: "mysql",
+			CfgItem:  "root:@tcp(localhost:3306)/gitea?charset=utf8",
+			Result:   "root:******@tcp(localhost:3306)/gitea?charset=utf8",
+		},
+		{
+			Provider: "mysql",
+			CfgItem:  "/gitea?charset=utf8",
+			Result:   "/gitea?charset=utf8",
+		},
+		{
+			Provider: "mysql",
+			CfgItem:  "user:mypassword@/dbname",
+			Result:   "user:******@/dbname",
+		},
+		{
+			Provider: "postgres",
+			CfgItem:  "user=pqgotest dbname=pqgotest sslmode=verify-full",
+			Result:   "user=pqgotest dbname=pqgotest sslmode=verify-full",
+		},
+		{
+			Provider: "postgres",
+			CfgItem:  "user=pqgotest password= dbname=pqgotest sslmode=verify-full",
+			Result:   "user=pqgotest password=****** dbname=pqgotest sslmode=verify-full",
+		},
+		{
+			Provider: "postgres",
+			CfgItem:  "postgres://user:pass@hostname/dbname",
+			Result:   "postgres://user:******@hostname/dbname",
+		},
+		{
+			Provider: "couchbase",
+			CfgItem:  "http://dev-couchbase.example.com:8091/",
+			Result:   "http://dev-couchbase.example.com:8091/",
+		},
+		{
+			Provider: "couchbase",
+			CfgItem:  "http://user:the_password@dev-couchbase.example.com:8091/",
+			Result:   "http://user:******@dev-couchbase.example.com:8091/",
+		},
+	}
+
+	for _, k := range kases {
+		assert.EqualValues(t, k.Result, shadowPassword(k.Provider, k.CfgItem))
+	}
+}