Git LFS support v2 (#122)

* Import github.com/git-lfs/lfs-test-server as lfs module base

Imported commit is 3968aac269a77b73924649b9412ae03f7ccd3198

Removed:

Dockerfile CONTRIBUTING.md mgmt* script/ vendor/ kvlogger.go
.dockerignore .gitignore README.md

* Remove config, add JWT support from github.com/mgit-at/lfs-test-server

Imported commit f0cdcc5a01599c5a955dc1bbf683bb4acecdba83

* Add LFS settings

* Add LFS meta object model

* Add LFS routes and initialization

* Import github.com/dgrijalva/jwt-go into vendor/

* Adapt LFS module: handlers, routing, meta store

* Move LFS routes to /user/repo/info/lfs/*

* Add request header checks to LFS BatchHandler / PostHandler

* Implement LFS basic authentication

* Rework JWT secret generation / load

* Implement LFS SSH token authentication with JWT

Specification: https://github.com/github/git-lfs/tree/master/docs/api

* Integrate LFS settings into install process

* Remove LFS objects when repository is deleted

Only removes objects from content store when deleted repo is the only
referencing repository

* Make LFS module stateless

Fixes bug where LFS would not work after installation without
restarting Gitea

* Change 500 'Internal Server Error' to 400 'Bad Request'

* Change sql query to xorm call

* Remove unneeded type from LFS module

* Change internal imports to code.gitea.io/gitea/

* Add Gitea authors copyright

* Change basic auth realm to "gitea-lfs"

* Add unique indexes to LFS model

* Use xorm count function in LFS check on repository delete

* Return io.ReadCloser from content store and close after usage

* Add LFS info to runWeb()

* Export LFS content store base path

* LFS file download from UI

* Work around git-lfs client issue with unauthenticated requests

Returning a dummy Authorization header for unauthenticated requests
lets git-lfs client skip asking for auth credentials
See: https://github.com/github/git-lfs/issues/1088

* Fix unauthenticated UI downloads from public repositories

* Authentication check order, Finish LFS file view logic

* Ignore LFS hooks if installed for current OS user

Fixes Gitea UI actions for repositories tracking LFS files.
Checks for minimum needed git version by parsing the semantic version
string.

* Hide LFS metafile diff from commit view, marking as binary

* Show LFS notice if file in commit view is tracked

* Add notbefore/nbf JWT claim

* Correct lint suggestions - comments for structs and functions

- Add comments to LFS model
- Function comment for GetRandomBytesAsBase64
- LFS server function comments and lint variable suggestion

* Move secret generation code out of conditional

Ensures no LFS code may run with an empty secret

* Do not hand out JWT tokens if LFS server support is disabled

models/git_diff.go

@@ -200,6 +200,7 @@ type DiffFile struct {
 	IsCreated          bool
 	IsDeleted          bool
 	IsBin              bool
+	IsLFSFile          bool
 	IsRenamed          bool
 	IsSubmodule        bool
 	Sections           []*DiffSection
@@ -245,6 +246,7 @@ func ParsePatch(maxLines, maxLineCharacteres, maxFiles int, reader io.Reader) (*
 		leftLine, rightLine int
 		lineCount           int
 		curFileLinesCount   int
+		curFileLFSPrefix    bool
 	)
 
 	input := bufio.NewReader(reader)
@@ -268,6 +270,28 @@ func ParsePatch(maxLines, maxLineCharacteres, maxFiles int, reader io.Reader) (*
 			continue
 		}
 
+		trimLine := strings.Trim(line, "+- ")
+
+		if trimLine == LFSMetaFileIdentifier {
+			curFileLFSPrefix = true
+		}
+
+		if curFileLFSPrefix && strings.HasPrefix(trimLine, LFSMetaFileOidPrefix) {
+			oid := strings.TrimPrefix(trimLine, LFSMetaFileOidPrefix)
+
+			if len(oid) == 64 {
+				m := &LFSMetaObject{Oid: oid}
+				count, err := x.Count(m)
+
+				if err == nil && count > 0 {
+					curFile.IsBin = true
+					curFile.IsLFSFile = true
+					curSection.Lines = nil
+					break
+				}
+			}
+		}
+
 		curFileLinesCount++
 		lineCount++
 
@@ -354,6 +378,7 @@ func ParsePatch(maxLines, maxLineCharacteres, maxFiles int, reader io.Reader) (*
 				break
 			}
 			curFileLinesCount = 0
+			curFileLFSPrefix = false
 
 			// Check file diff type and is submodule.
 			for {