forgejo-federation/modules/test/context_tests.go
wxiaoguang 722dab5286
Make HTML template functions support context (#24056)
# Background

Golang template is not friendly for large projects, and Golang template
team is quite slow, related:
* `https://github.com/golang/go/issues/54450`

Without upstream support, we can also have our solution to make HTML
template functions support context.

It helps a lot, the above Golang template issue `#54450` explains a lot:

1. It makes `{{Locale.Tr}}` could be used in any template, without
passing unclear `(dict "root" . )` anymore.
2. More and more functions need `context`, like `avatar`, etc, we do not
need to do `(dict "Context" $.Context)` anymore.
3. Many request-related functions could be shared by parent&children
templates, like "user setting" / "system setting"

See the test `TestScopedTemplateSetFuncMap`, one template set, two
`Execute` calls with different `CtxFunc`.

# The Solution

Instead of waiting for upstream, this PR re-uses the escaped HTML
template trees, use `AddParseTree` to add related templates/trees to a
new template instance, then the new template instance can have its own
FuncMap , the function calls in the template trees will always use the
new template's FuncMap.

`template.New` / `template.AddParseTree` / `adding-FuncMap` are all
quite fast, so the performance is not affected.

The details:

1. Make a new `html/template/Template` for `all` templates
2. Add template code to the `all` template
3. Freeze the `all` template, reset its exec func map, it shouldn't
execute any template.
4. When a router wants to render a template by its `name`
    1. Find the `name` in `all`
    2. Find all its related sub templates
3. Escape all related templates (just like what the html template
package does)
4. Add the escaped parse-trees of related templates into a new (scoped)
`text/template/Template`
    5. Add context-related func map into the new (scoped) text template
    6. Execute the new (scoped) text template
7. To improve performance, the escaped templates are cached to `template
sets`

# FAQ

## There is a `unsafe` call, is this PR unsafe?

This PR is safe. Golang has strict language definition, it's safe to do
so: https://pkg.go.dev/unsafe#Pointer (1) Conversion of a *T1 to Pointer
to *T2


## What if Golang template supports such feature in the future?

The public structs/interfaces/functions introduced by this PR is quite
simple, the code of `HTMLRender` is not changed too much. It's very easy
to switch to the official mechanism if there would be one.

## Does this PR change the template execution behavior?

No, see the tests (welcome to design more tests if it's necessary)

---------

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: Jason Song <i@wolfogre.com>
Co-authored-by: Giteabot <teabot@gitea.io>
2023-04-20 04:08:58 -04:00

132 lines
3.6 KiB
Go

// Copyright 2017 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package test
import (
scontext "context"
"io"
"net/http"
"net/http/httptest"
"net/url"
"testing"
access_model "code.gitea.io/gitea/models/perm/access"
repo_model "code.gitea.io/gitea/models/repo"
"code.gitea.io/gitea/models/unittest"
user_model "code.gitea.io/gitea/models/user"
"code.gitea.io/gitea/modules/context"
"code.gitea.io/gitea/modules/git"
"code.gitea.io/gitea/modules/templates"
"code.gitea.io/gitea/modules/translation"
"code.gitea.io/gitea/modules/web/middleware"
chi "github.com/go-chi/chi/v5"
"github.com/stretchr/testify/assert"
)
// MockContext mock context for unit tests
func MockContext(t *testing.T, path string) *context.Context {
resp := &mockResponseWriter{}
ctx := context.Context{
Render: &mockRender{},
Data: make(map[string]interface{}),
Flash: &middleware.Flash{
Values: make(url.Values),
},
Resp: context.NewResponse(resp),
Locale: &translation.MockLocale{},
}
defer ctx.Close()
requestURL, err := url.Parse(path)
assert.NoError(t, err)
req := &http.Request{
URL: requestURL,
Form: url.Values{},
}
chiCtx := chi.NewRouteContext()
req = req.WithContext(scontext.WithValue(req.Context(), chi.RouteCtxKey, chiCtx))
ctx.Req = context.WithContext(req, &ctx)
return &ctx
}
// LoadRepo load a repo into a test context.
func LoadRepo(t *testing.T, ctx *context.Context, repoID int64) {
ctx.Repo = &context.Repository{}
ctx.Repo.Repository = unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: repoID})
var err error
ctx.Repo.Owner, err = user_model.GetUserByID(ctx, ctx.Repo.Repository.OwnerID)
assert.NoError(t, err)
ctx.Repo.RepoLink = ctx.Repo.Repository.Link()
ctx.Repo.Permission, err = access_model.GetUserRepoPermission(ctx, ctx.Repo.Repository, ctx.Doer)
assert.NoError(t, err)
}
// LoadRepoCommit loads a repo's commit into a test context.
func LoadRepoCommit(t *testing.T, ctx *context.Context) {
gitRepo, err := git.OpenRepository(ctx, ctx.Repo.Repository.RepoPath())
assert.NoError(t, err)
defer gitRepo.Close()
branch, err := gitRepo.GetHEADBranch()
assert.NoError(t, err)
assert.NotNil(t, branch)
if branch != nil {
ctx.Repo.Commit, err = gitRepo.GetBranchCommit(branch.Name)
assert.NoError(t, err)
}
}
// LoadUser load a user into a test context.
func LoadUser(t *testing.T, ctx *context.Context, userID int64) {
ctx.Doer = unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: userID})
}
// LoadGitRepo load a git repo into a test context. Requires that ctx.Repo has
// already been populated.
func LoadGitRepo(t *testing.T, ctx *context.Context) {
assert.NoError(t, ctx.Repo.Repository.LoadOwner(ctx))
var err error
ctx.Repo.GitRepo, err = git.OpenRepository(ctx, ctx.Repo.Repository.RepoPath())
assert.NoError(t, err)
}
type mockResponseWriter struct {
httptest.ResponseRecorder
size int
}
func (rw *mockResponseWriter) Write(b []byte) (int, error) {
rw.size += len(b)
return rw.ResponseRecorder.Write(b)
}
func (rw *mockResponseWriter) Status() int {
return rw.ResponseRecorder.Code
}
func (rw *mockResponseWriter) Written() bool {
return rw.ResponseRecorder.Code > 0
}
func (rw *mockResponseWriter) Size() int {
return rw.size
}
func (rw *mockResponseWriter) Push(target string, opts *http.PushOptions) error {
return nil
}
type mockRender struct{}
func (tr *mockRender) TemplateLookup(tmpl string) (templates.TemplateExecutor, error) {
return nil, nil
}
func (tr *mockRender) HTML(w io.Writer, status int, _ string, _ interface{}) error {
if resp, ok := w.(http.ResponseWriter); ok {
resp.WriteHeader(status)
}
return nil
}