From b80d34f42371da5d62b862ffe537cde0e80091a7 Mon Sep 17 00:00:00 2001
From: Vincent Batts <vbatts@hashbangbash.com>
Date: Fri, 7 Apr 2017 11:56:05 -0400
Subject: [PATCH] dbutil: abstract out the last mongo type

Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
---
 dbutil/dbutil.go       | 19 ++++++++++++++++---
 dbutil/mongo/handle.go |  4 ++--
 types/types.go         | 31 +++++++++++++------------------
 3 files changed, 31 insertions(+), 23 deletions(-)

diff --git a/dbutil/dbutil.go b/dbutil/dbutil.go
index 24220ba..bcc6705 100644
--- a/dbutil/dbutil.go
+++ b/dbutil/dbutil.go
@@ -1,8 +1,9 @@
 package dbutil
 
 import (
+	"io"
+
 	"github.com/vbatts/imgsrv/types"
-	"labix.org/v2/mgo"
 )
 
 // Handles are all the register backing Handlers
@@ -13,8 +14,8 @@ type Handler interface {
 	Init(config interface{}) error
 	Close() error
 
-	Open(filename string) (*mgo.GridFile, error)
-	Create(filename string) (*mgo.GridFile, error)
+	Open(filename string) (File, error)
+	Create(filename string) (File, error)
 	Remove(filename string) error
 
 	//HasFileByMd5(md5 string) (exists bool, err error)
@@ -31,3 +32,15 @@ type Handler interface {
 	GetExtensions() (kp []types.IdCount, err error)
 	GetKeywords() (kp []types.IdCount, err error)
 }
+
+type MetaDataer interface {
+	GetMeta(result interface{}) (err error)
+	SetMeta(metadata interface{})
+}
+
+type File interface {
+	io.Reader
+	io.Writer
+	io.Closer
+	MetaDataer
+}
diff --git a/dbutil/mongo/handle.go b/dbutil/mongo/handle.go
index 889efa8..18e69c8 100644
--- a/dbutil/mongo/handle.go
+++ b/dbutil/mongo/handle.go
@@ -59,12 +59,12 @@ func (h mongoHandle) Close() error {
 }
 
 // pass through for GridFs
-func (h mongoHandle) Open(filename string) (file *mgo.GridFile, err error) {
+func (h mongoHandle) Open(filename string) (file dbutil.File, err error) {
 	return h.Gfs.Open(strings.ToLower(filename))
 }
 
 // pass through for GridFs
-func (h mongoHandle) Create(filename string) (file *mgo.GridFile, err error) {
+func (h mongoHandle) Create(filename string) (file dbutil.File, err error) {
 	return h.Gfs.Create(strings.ToLower(filename))
 }
 
diff --git a/types/types.go b/types/types.go
index 3737ccf..35101c6 100644
--- a/types/types.go
+++ b/types/types.go
@@ -15,37 +15,32 @@ type Info struct {
 }
 
 type File struct {
-	Metadata    Info ",omitempty"
-	Md5         string
-	ChunkSize   int
-	UploadDate  time.Time
-	Length      int64
-	Filename    string ",omitempty"
-	ContentType string "contentType,omitempty"
+	Metadata   Info ",omitempty"
+	Md5        string
+	ChunkSize  int
+	UploadDate time.Time
+	Length     int64
+	Filename   string ",omitempty"
 }
 
-func (f *File) SetContentType() {
-	f.ContentType = mime.TypeByExtension(filepath.Ext(f.Filename))
+// ContentType guesses the mime-type by the file's extension
+func (f *File) ContentType() string {
+	return mime.TypeByExtension(filepath.Ext(f.Filename))
 }
 
 func (f *File) IsImage() bool {
-	f.SetContentType()
-	return strings.HasPrefix(f.ContentType, "image")
+	return strings.HasPrefix(f.ContentType(), "image")
 }
 
 func (f *File) IsVideo() bool {
-	f.SetContentType()
-	return strings.HasPrefix(f.ContentType, "video")
+	return strings.HasPrefix(f.ContentType(), "video")
 }
 
 func (f *File) IsAudio() bool {
-	f.SetContentType()
-	return strings.HasPrefix(f.ContentType, "audio")
+	return strings.HasPrefix(f.ContentType(), "audio")
 }
 
-/*
-Structure used for collecting values from mongo for a tag cloud
-*/
+// IdCount structure used for collecting values for a tag cloud
 type IdCount struct {
 	Id    string "_id"
 	Value int