Propagate context and ensure git commands run in request context (#17868)

This PR continues the work in #17125 by progressively ensuring that git
commands run within the request context.

This now means that the if there is a git repo already open in the context it will be used instead of reopening it.

Signed-off-by: Andrew Thornton <art27@cantab.net>

4 files changed, 75 insertions, 30 deletions

diff --git a/modules/context/api.go b/modules/context/api.go
index b079385aff..dae6d23989 100644
--- a/modules/context/api.go
+++ b/modules/context/api.go
@@ -303,6 +303,7 @@ func APIContexter() func(http.Handler) http.Handler {
 			ctx.Resp.Header().Set(`X-Frame-Options`, setting.CORSConfig.XFrameOptions)
 
 			ctx.Data["CsrfToken"] = html.EscapeString(ctx.csrf.GetToken())
+			ctx.Data["Context"] = &ctx
 
 			next.ServeHTTP(ctx.Resp, ctx.Req)
 
@@ -321,35 +322,32 @@ func APIContexter() func(http.Handler) http.Handler {
 }
 
 // ReferencesGitRepo injects the GitRepo into the Context
-func ReferencesGitRepo(allowEmpty bool) func(http.Handler) http.Handler {
-	return func(next http.Handler) http.Handler {
-		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
-			ctx := GetAPIContext(req)
-			// Empty repository does not have reference information.
-			if !allowEmpty && ctx.Repo.Repository.IsEmpty {
+func ReferencesGitRepo(allowEmpty bool) func(ctx *APIContext) (cancel context.CancelFunc) {
+	return func(ctx *APIContext) (cancel context.CancelFunc) {
+		// Empty repository does not have reference information.
+		if !allowEmpty && ctx.Repo.Repository.IsEmpty {
+			return
+		}
+
+		// For API calls.
+		if ctx.Repo.GitRepo == nil {
+			repoPath := repo_model.RepoPath(ctx.Repo.Owner.Name, ctx.Repo.Repository.Name)
+			gitRepo, err := git.OpenRepositoryCtx(ctx, repoPath)
+			if err != nil {
+				ctx.Error(http.StatusInternalServerError, "RepoRef Invalid repo "+repoPath, err)
 				return
 			}
-
-			// For API calls.
-			if ctx.Repo.GitRepo == nil {
-				repoPath := repo_model.RepoPath(ctx.Repo.Owner.Name, ctx.Repo.Repository.Name)
-				gitRepo, err := git.OpenRepository(repoPath)
-				if err != nil {
-					ctx.Error(http.StatusInternalServerError, "RepoRef Invalid repo "+repoPath, err)
-					return
+			ctx.Repo.GitRepo = gitRepo
+			// We opened it, we should close it
+			return func() {
+				// If it's been set to nil then assume someone else has closed it.
+				if ctx.Repo.GitRepo != nil {
+					ctx.Repo.GitRepo.Close()
 				}
-				ctx.Repo.GitRepo = gitRepo
-				// We opened it, we should close it
-				defer func() {
-					// If it's been set to nil then assume someone else has closed it.
-					if ctx.Repo.GitRepo != nil {
-						ctx.Repo.GitRepo.Close()
-					}
-				}()
 			}
+		}
 
-			next.ServeHTTP(w, req)
-		})
+		return
 	}
 }
 
@@ -391,7 +389,7 @@ func RepoRefForAPI(next http.Handler) http.Handler {
 
 		if ctx.Repo.GitRepo == nil {
 			repoPath := repo_model.RepoPath(ctx.Repo.Owner.Name, ctx.Repo.Repository.Name)
-			ctx.Repo.GitRepo, err = git.OpenRepository(repoPath)
+			ctx.Repo.GitRepo, err = git.OpenRepositoryCtx(ctx, repoPath)
 			if err != nil {
 				ctx.InternalServerError(err)
 				return
diff --git a/modules/context/context.go b/modules/context/context.go
index 5038850649..ab83ae4eb5 100644
--- a/modules/context/context.go
+++ b/modules/context/context.go
@@ -23,6 +23,7 @@ import (
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/base"
 	mc "code.gitea.io/gitea/modules/cache"
+	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/json"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
@@ -529,6 +530,10 @@ func (ctx *Context) Err() error {
 
 // Value is part of the interface for context.Context and we pass this to the request context
 func (ctx *Context) Value(key interface{}) interface{} {
+	if key == git.RepositoryContextKey && ctx.Repo != nil {
+		return ctx.Repo.GitRepo
+	}
+
 	return ctx.Req.Context().Value(key)
 }
 
@@ -631,6 +636,7 @@ func Contexter() func(next http.Handler) http.Handler {
 			// PageData is passed by reference, and it will be rendered to `window.config.pageData` in `head.tmpl` for JavaScript modules
 			ctx.PageData = map[string]interface{}{}
 			ctx.Data["PageData"] = ctx.PageData
+			ctx.Data["Context"] = &ctx
 
 			ctx.Req = WithContext(req, &ctx)
 			ctx.csrf = Csrfer(csrfOpts, &ctx)
diff --git a/modules/context/private.go b/modules/context/private.go
index dfefa1d2f0..3e31a7e7d8 100644
--- a/modules/context/private.go
+++ b/modules/context/private.go
@@ -6,12 +6,42 @@ package context
 
 import (
 	"context"
+	"fmt"
 	"net/http"
+	"time"
+
+	"code.gitea.io/gitea/modules/graceful"
+	"code.gitea.io/gitea/modules/process"
 )
 
 // PrivateContext represents a context for private routes
 type PrivateContext struct {
 	*Context
+	Override context.Context
+}
+
+// Deadline is part of the interface for context.Context and we pass this to the request context
+func (ctx *PrivateContext) Deadline() (deadline time.Time, ok bool) {
+	if ctx.Override != nil {
+		return ctx.Override.Deadline()
+	}
+	return ctx.Req.Context().Deadline()
+}
+
+// Done is part of the interface for context.Context and we pass this to the request context
+func (ctx *PrivateContext) Done() <-chan struct{} {
+	if ctx.Override != nil {
+		return ctx.Override.Done()
+	}
+	return ctx.Req.Context().Done()
+}
+
+// Err is part of the interface for context.Context and we pass this to the request context
+func (ctx *PrivateContext) Err() error {
+	if ctx.Override != nil {
+		return ctx.Override.Err()
+	}
+	return ctx.Req.Context().Err()
 }
 
 var (
@@ -39,7 +69,18 @@ func PrivateContexter() func(http.Handler) http.Handler {
 				},
 			}
 			ctx.Req = WithPrivateContext(req, ctx)
+			ctx.Data["Context"] = ctx
 			next.ServeHTTP(ctx.Resp, ctx.Req)
 		})
 	}
 }
+
+// OverrideContext overrides the underlying request context for Done() etc.
+// This function should be used when there is a need for work to continue even if the request has been cancelled.
+// Primarily this affects hook/post-receive and hook/proc-receive both of which need to continue working even if
+// the underlying request has timed out from the ssh/http push
+func OverrideContext(ctx *PrivateContext) (cancel context.CancelFunc) {
+	// We now need to override the request context as the base for our work because even if the request is cancelled we have to continue this work
+	ctx.Override, _, cancel = process.GetManager().AddContext(graceful.GetManager().HammerContext(), fmt.Sprintf("PrivateContext: %s", ctx.Req.RequestURI))
+	return
+}
diff --git a/modules/context/repo.go b/modules/context/repo.go
index bf782383b5..4acb800b64 100644
--- a/modules/context/repo.go
+++ b/modules/context/repo.go
@@ -109,7 +109,7 @@ type CanCommitToBranchResults struct {
 
 // CanCommitToBranch returns true if repository is editable and user has proper access level
 //   and branch is not protected for push
-func (r *Repository) CanCommitToBranch(doer *user_model.User) (CanCommitToBranchResults, error) {
+func (r *Repository) CanCommitToBranch(ctx context.Context, doer *user_model.User) (CanCommitToBranchResults, error) {
 	protectedBranch, err := models.GetProtectedBranchBy(r.Repository.ID, r.BranchName)
 
 	if err != nil {
@@ -122,7 +122,7 @@ func (r *Repository) CanCommitToBranch(doer *user_model.User) (CanCommitToBranch
 		requireSigned = protectedBranch.RequireSignedCommits
 	}
 
-	sign, keyID, _, err := asymkey_service.SignCRUDAction(r.Repository.RepoPath(), doer, r.Repository.RepoPath(), git.BranchPrefix+r.BranchName)
+	sign, keyID, _, err := asymkey_service.SignCRUDAction(ctx, r.Repository.RepoPath(), doer, r.Repository.RepoPath(), git.BranchPrefix+r.BranchName)
 
 	canCommit := r.CanEnableEditor() && userCanPush
 	if requireSigned {
@@ -180,14 +180,14 @@ func (r *Repository) GetCommitsCount() (int64, error) {
 }
 
 // GetCommitGraphsCount returns cached commit count for current view
-func (r *Repository) GetCommitGraphsCount(hidePRRefs bool, branches, files []string) (int64, error) {
+func (r *Repository) GetCommitGraphsCount(ctx context.Context, hidePRRefs bool, branches, files []string) (int64, error) {
 	cacheKey := fmt.Sprintf("commits-count-%d-graph-%t-%s-%s", r.Repository.ID, hidePRRefs, branches, files)
 
 	return cache.GetInt64(cacheKey, func() (int64, error) {
 		if len(branches) == 0 {
-			return git.AllCommitsCount(r.Repository.RepoPath(), hidePRRefs, files...)
+			return git.AllCommitsCount(ctx, r.Repository.RepoPath(), hidePRRefs, files...)
 		}
-		return git.CommitsCountFiles(r.Repository.RepoPath(), branches, files)
+		return git.CommitsCountFiles(ctx, r.Repository.RepoPath(), branches, files)
 	})
 }