From 6782a64a4ab0d3e0f6537b739f263c596be9bbb3 Mon Sep 17 00:00:00 2001
From: zeripath <art27@cantab.net>
Date: Fri, 7 May 2021 17:28:02 +0100
Subject: [PATCH] Defer closing the gitrepo until the end of the wrapped
 context functions (#15653) (#15746)

* Defer closing the gitrepo until the end of the wrapped context functions (#15653)

Backport #15653

There was a mistake in #15372 where deferral of gitrepo close occurs before it should.

This PR fixes this.
---
 modules/context/repo.go | 19 +++++++++++--------
 modules/web/route.go    | 30 ++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 8 deletions(-)

diff --git a/modules/context/repo.go b/modules/context/repo.go
index a77d075de2..c1f60a1362 100644
--- a/modules/context/repo.go
+++ b/modules/context/repo.go
@@ -6,6 +6,7 @@
 package context
 
 import (
+	"context"
 	"fmt"
 	"io/ioutil"
 	"net/url"
@@ -393,7 +394,7 @@ func RepoIDAssignment() func(ctx *Context) {
 }
 
 // RepoAssignment returns a middleware to handle repository assignment
-func RepoAssignment(ctx *Context) {
+func RepoAssignment(ctx *Context) (cancel context.CancelFunc) {
 	var (
 		owner *models.User
 		err   error
@@ -529,12 +530,12 @@ func RepoAssignment(ctx *Context) {
 	ctx.Repo.GitRepo = gitRepo
 
 	// We opened it, we should close it
-	defer func() {
+	cancel = func() {
 		// If it's been set to nil then assume someone else has closed it.
 		if ctx.Repo.GitRepo != nil {
 			ctx.Repo.GitRepo.Close()
 		}
-	}()
+	}
 
 	// Stop at this point when the repo is empty.
 	if ctx.Repo.Repository.IsEmpty {
@@ -619,6 +620,7 @@ func RepoAssignment(ctx *Context) {
 		ctx.Data["GoDocDirectory"] = prefix + "{/dir}"
 		ctx.Data["GoDocFile"] = prefix + "{/dir}/{file}#L{line}"
 	}
+	return
 }
 
 // RepoRefType type of repo reference
@@ -643,7 +645,7 @@ const (
 
 // RepoRef handles repository reference names when the ref name is not
 // explicitly given
-func RepoRef() func(*Context) {
+func RepoRef() func(*Context) context.CancelFunc {
 	// since no ref name is explicitly specified, ok to just use branch
 	return RepoRefByType(RepoRefBranch)
 }
@@ -722,8 +724,8 @@ func getRefName(ctx *Context, pathType RepoRefType) string {
 
 // RepoRefByType handles repository reference name for a specific type
 // of repository reference
-func RepoRefByType(refType RepoRefType, ignoreNotExistErr ...bool) func(*Context) {
-	return func(ctx *Context) {
+func RepoRefByType(refType RepoRefType, ignoreNotExistErr ...bool) func(*Context) context.CancelFunc {
+	return func(ctx *Context) (cancel context.CancelFunc) {
 		// Empty repository does not have reference information.
 		if ctx.Repo.Repository.IsEmpty {
 			return
@@ -742,12 +744,12 @@ func RepoRefByType(refType RepoRefType, ignoreNotExistErr ...bool) func(*Context
 				return
 			}
 			// We opened it, we should close it
-			defer func() {
+			cancel = func() {
 				// If it's been set to nil then assume someone else has closed it.
 				if ctx.Repo.GitRepo != nil {
 					ctx.Repo.GitRepo.Close()
 				}
-			}()
+			}
 		}
 
 		// Get default branch.
@@ -844,6 +846,7 @@ func RepoRefByType(refType RepoRefType, ignoreNotExistErr ...bool) func(*Context
 			return
 		}
 		ctx.Data["CommitsCount"] = ctx.Repo.CommitsCount
+		return
 	}
 }
 
diff --git a/modules/web/route.go b/modules/web/route.go
index 6f9e76bdf3..319d08f598 100644
--- a/modules/web/route.go
+++ b/modules/web/route.go
@@ -5,6 +5,7 @@
 package web
 
 import (
+	goctx "context"
 	"fmt"
 	"net/http"
 	"reflect"
@@ -27,6 +28,7 @@ func Wrap(handlers ...interface{}) http.HandlerFunc {
 		switch t := handler.(type) {
 		case http.HandlerFunc, func(http.ResponseWriter, *http.Request),
 			func(ctx *context.Context),
+			func(ctx *context.Context) goctx.CancelFunc,
 			func(*context.APIContext),
 			func(*context.PrivateContext),
 			func(http.Handler) http.Handler:
@@ -48,6 +50,15 @@ func Wrap(handlers ...interface{}) http.HandlerFunc {
 				if r, ok := resp.(context.ResponseWriter); ok && r.Status() > 0 {
 					return
 				}
+			case func(ctx *context.Context) goctx.CancelFunc:
+				ctx := context.GetContext(req)
+				cancel := t(ctx)
+				if cancel != nil {
+					defer cancel()
+				}
+				if ctx.Written() {
+					return
+				}
 			case func(ctx *context.Context):
 				ctx := context.GetContext(req)
 				t(ctx)
@@ -94,6 +105,23 @@ func Middle(f func(ctx *context.Context)) func(netx http.Handler) http.Handler {
 	}
 }
 
+// MiddleCancel wrap a context function as a chi middleware
+func MiddleCancel(f func(ctx *context.Context) goctx.CancelFunc) func(netx http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(resp http.ResponseWriter, req *http.Request) {
+			ctx := context.GetContext(req)
+			cancel := f(ctx)
+			if cancel != nil {
+				defer cancel()
+			}
+			if ctx.Written() {
+				return
+			}
+			next.ServeHTTP(ctx.Resp, ctx.Req)
+		})
+	}
+}
+
 // MiddleAPI wrap a context function as a chi middleware
 func MiddleAPI(f func(ctx *context.APIContext)) func(netx http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
@@ -163,6 +191,8 @@ func (r *Route) Use(middlewares ...interface{}) {
 				r.R.Use(t)
 			case func(*context.Context):
 				r.R.Use(Middle(t))
+			case func(*context.Context) goctx.CancelFunc:
+				r.R.Use(MiddleCancel(t))
 			case func(*context.APIContext):
 				r.R.Use(MiddleAPI(t))
 			default: