forgejo/routers/api/v1/user/follower.go
Lunny Xiao bd820aa9c5
Add context cache as a request level cache (#22294)
To avoid duplicated load of the same data in an HTTP request, we can set
a context cache to do that. i.e. Some pages may load a user from a
database with the same id in different areas on the same page. But the
code is hidden in two different deep logic. How should we share the
user? As a result of this PR, now if both entry functions accept
`context.Context` as the first parameter and we just need to refactor
`GetUserByID` to reuse the user from the context cache. Then it will not
be loaded twice on an HTTP request.

But of course, sometimes we would like to reload an object from the
database, that's why `RemoveContextData` is also exposed.

The core context cache is here. It defines a new context
```go
type cacheContext struct {
	ctx  context.Context
	data map[any]map[any]any
        lock sync.RWMutex
}

var cacheContextKey = struct{}{}

func WithCacheContext(ctx context.Context) context.Context {
	return context.WithValue(ctx, cacheContextKey, &cacheContext{
		ctx:  ctx,
		data: make(map[any]map[any]any),
	})
}
```

Then you can use the below 4 methods to read/write/del the data within
the same context.

```go
func GetContextData(ctx context.Context, tp, key any) any
func SetContextData(ctx context.Context, tp, key, value any)
func RemoveContextData(ctx context.Context, tp, key any)
func GetWithContextCache[T any](ctx context.Context, cacheGroupKey string, cacheTargetID any, f func() (T, error)) (T, error)
```

Then let's take a look at how `system.GetString` implement it.

```go
func GetSetting(ctx context.Context, key string) (string, error) {
	return cache.GetWithContextCache(ctx, contextCacheKey, key, func() (string, error) {
		return cache.GetString(genSettingCacheKey(key), func() (string, error) {
			res, err := GetSettingNoCache(ctx, key)
			if err != nil {
				return "", err
			}
			return res.SettingValue, nil
		})
	})
}
```

First, it will check if context data include the setting object with the
key. If not, it will query from the global cache which may be memory or
a Redis cache. If not, it will get the object from the database. In the
end, if the object gets from the global cache or database, it will be
set into the context cache.

An object stored in the context cache will only be destroyed after the
context disappeared.
2023-02-15 21:37:34 +08:00

248 lines
6.6 KiB
Go

// Copyright 2015 The Gogs Authors. All rights reserved.
// Copyright 2020 The Gitea Authors.
// SPDX-License-Identifier: MIT
package user
import (
"net/http"
user_model "code.gitea.io/gitea/models/user"
"code.gitea.io/gitea/modules/context"
api "code.gitea.io/gitea/modules/structs"
"code.gitea.io/gitea/routers/api/v1/utils"
"code.gitea.io/gitea/services/convert"
)
func responseAPIUsers(ctx *context.APIContext, users []*user_model.User) {
apiUsers := make([]*api.User, len(users))
for i := range users {
apiUsers[i] = convert.ToUser(ctx, users[i], ctx.Doer)
}
ctx.JSON(http.StatusOK, &apiUsers)
}
func listUserFollowers(ctx *context.APIContext, u *user_model.User) {
users, count, err := user_model.GetUserFollowers(ctx, u, ctx.Doer, utils.GetListOptions(ctx))
if err != nil {
ctx.Error(http.StatusInternalServerError, "GetUserFollowers", err)
return
}
ctx.SetTotalCountHeader(count)
responseAPIUsers(ctx, users)
}
// ListMyFollowers list the authenticated user's followers
func ListMyFollowers(ctx *context.APIContext) {
// swagger:operation GET /user/followers user userCurrentListFollowers
// ---
// summary: List the authenticated user's followers
// parameters:
// - name: page
// in: query
// description: page number of results to return (1-based)
// type: integer
// - name: limit
// in: query
// description: page size of results
// type: integer
// produces:
// - application/json
// responses:
// "200":
// "$ref": "#/responses/UserList"
listUserFollowers(ctx, ctx.Doer)
}
// ListFollowers list the given user's followers
func ListFollowers(ctx *context.APIContext) {
// swagger:operation GET /users/{username}/followers user userListFollowers
// ---
// summary: List the given user's followers
// produces:
// - application/json
// parameters:
// - name: username
// in: path
// description: username of user
// type: string
// required: true
// - name: page
// in: query
// description: page number of results to return (1-based)
// type: integer
// - name: limit
// in: query
// description: page size of results
// type: integer
// responses:
// "200":
// "$ref": "#/responses/UserList"
listUserFollowers(ctx, ctx.ContextUser)
}
func listUserFollowing(ctx *context.APIContext, u *user_model.User) {
users, count, err := user_model.GetUserFollowing(ctx, u, ctx.Doer, utils.GetListOptions(ctx))
if err != nil {
ctx.Error(http.StatusInternalServerError, "GetUserFollowing", err)
return
}
ctx.SetTotalCountHeader(count)
responseAPIUsers(ctx, users)
}
// ListMyFollowing list the users that the authenticated user is following
func ListMyFollowing(ctx *context.APIContext) {
// swagger:operation GET /user/following user userCurrentListFollowing
// ---
// summary: List the users that the authenticated user is following
// parameters:
// - name: page
// in: query
// description: page number of results to return (1-based)
// type: integer
// - name: limit
// in: query
// description: page size of results
// type: integer
// produces:
// - application/json
// responses:
// "200":
// "$ref": "#/responses/UserList"
listUserFollowing(ctx, ctx.Doer)
}
// ListFollowing list the users that the given user is following
func ListFollowing(ctx *context.APIContext) {
// swagger:operation GET /users/{username}/following user userListFollowing
// ---
// summary: List the users that the given user is following
// produces:
// - application/json
// parameters:
// - name: username
// in: path
// description: username of user
// type: string
// required: true
// - name: page
// in: query
// description: page number of results to return (1-based)
// type: integer
// - name: limit
// in: query
// description: page size of results
// type: integer
// responses:
// "200":
// "$ref": "#/responses/UserList"
listUserFollowing(ctx, ctx.ContextUser)
}
func checkUserFollowing(ctx *context.APIContext, u *user_model.User, followID int64) {
if user_model.IsFollowing(u.ID, followID) {
ctx.Status(http.StatusNoContent)
} else {
ctx.NotFound()
}
}
// CheckMyFollowing whether the given user is followed by the authenticated user
func CheckMyFollowing(ctx *context.APIContext) {
// swagger:operation GET /user/following/{username} user userCurrentCheckFollowing
// ---
// summary: Check whether a user is followed by the authenticated user
// parameters:
// - name: username
// in: path
// description: username of followed user
// type: string
// required: true
// responses:
// "204":
// "$ref": "#/responses/empty"
// "404":
// "$ref": "#/responses/notFound"
checkUserFollowing(ctx, ctx.Doer, ctx.ContextUser.ID)
}
// CheckFollowing check if one user is following another user
func CheckFollowing(ctx *context.APIContext) {
// swagger:operation GET /users/{username}/following/{target} user userCheckFollowing
// ---
// summary: Check if one user is following another user
// parameters:
// - name: username
// in: path
// description: username of following user
// type: string
// required: true
// - name: target
// in: path
// description: username of followed user
// type: string
// required: true
// responses:
// "204":
// "$ref": "#/responses/empty"
// "404":
// "$ref": "#/responses/notFound"
target := GetUserByParamsName(ctx, ":target")
if ctx.Written() {
return
}
checkUserFollowing(ctx, ctx.ContextUser, target.ID)
}
// Follow follow a user
func Follow(ctx *context.APIContext) {
// swagger:operation PUT /user/following/{username} user userCurrentPutFollow
// ---
// summary: Follow a user
// parameters:
// - name: username
// in: path
// description: username of user to follow
// type: string
// required: true
// responses:
// "204":
// "$ref": "#/responses/empty"
if err := user_model.FollowUser(ctx.Doer.ID, ctx.ContextUser.ID); err != nil {
ctx.Error(http.StatusInternalServerError, "FollowUser", err)
return
}
ctx.Status(http.StatusNoContent)
}
// Unfollow unfollow a user
func Unfollow(ctx *context.APIContext) {
// swagger:operation DELETE /user/following/{username} user userCurrentDeleteFollow
// ---
// summary: Unfollow a user
// parameters:
// - name: username
// in: path
// description: username of user to unfollow
// type: string
// required: true
// responses:
// "204":
// "$ref": "#/responses/empty"
if err := user_model.UnfollowUser(ctx.Doer.ID, ctx.ContextUser.ID); err != nil {
ctx.Error(http.StatusInternalServerError, "UnfollowUser", err)
return
}
ctx.Status(http.StatusNoContent)
}