Qor与Beego整合时遇到空指针错误或无效内存地址问题

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我有一个使用 beego 框架的简单 web 应用程序。我最近发现并想与 beego 一起使用它。

我已按照此文档将 qor 与我的 beego web 应用程序集成。

部署时，一切都很顺利。容器构建并运行得很好，并且我的网络应用程序的原始部分都按预期工作。但是，在尝试访问 /admin 页面时出现以下错误：

beego-app:runtime error: invalid memory address or nil pointer dereference
request method: get
request url:    /admin
remoteaddr: redacted
stack
/usr/local/go/src/runtime/panic.go:838
/usr/local/go/src/runtime/panic.go:220
/usr/local/go/src/runtime/signal_unix.go:818
/usr/local/go/src/html/template/template.go:97
/usr/local/go/src/html/template/template.go:121
/go/pkg/mod/github.com/qor/[email protected]/context.go:227
/go/pkg/mod/github.com/qor/[email protected]/controller.go:28
/go/pkg/mod/github.com/qor/[email protected]/route.go:197
/go/pkg/mod/github.com/qor/[email protected]/route.go:38
/go/pkg/mod/github.com/qor/[email protected]/route.go:187
/go/pkg/mod/github.com/qor/[email protected]/route.go:38
/go/pkg/mod/github.com/qor/[email protected]/composite_primary_key_callback.go:27
/go/pkg/mod/github.com/qor/[email protected]/route.go:288
/usr/local/go/src/net/http/server.go:2462
/go/pkg/mod/github.com/astaxie/[email protected]/router.go:820
/usr/local/go/src/net/http/server.go:2916
/usr/local/go/src/net/http/server.go:1966
/usr/local/go/src/runtime/asm_amd64.s:1571
beego 1.12.3 (beego framework)

golang version: go1.18.3

这是我从 gcp 获得的日志：

default
2022-07-21t20:18:54.881125z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /go/pkg/mod/github.com/qor/[email protected]/controller.go:28
default
2022-07-21t20:18:54.881131z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /go/pkg/mod/github.com/qor/[email protected]/route.go:197
default
2022-07-21t20:18:54.881138z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /go/pkg/mod/github.com/qor/[email protected]/route.go:38
default
2022-07-21t20:18:54.881144z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /go/pkg/mod/github.com/qor/[email protected]/route.go:187
default
2022-07-21t20:18:54.881152z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /go/pkg/mod/github.com/qor/[email protected]/route.go:38
default
2022-07-21t20:18:54.881161z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /go/pkg/mod/github.com/qor/[email protected]/composite_primary_key_callback.go:27
default
2022-07-21t20:18:54.881168z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /go/pkg/mod/github.com/qor/[email protected]/route.go:288
default
2022-07-21t20:18:54.881174z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /usr/local/go/src/net/http/server.go:2462
default
2022-07-21t20:18:54.881181z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /go/pkg/mod/github.com/astaxie/[email protected]/router.go:820
default
2022-07-21t20:18:54.881248z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /usr/local/go/src/net/http/server.go:2916
default
2022-07-21t20:18:54.881336z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /usr/local/go/src/net/http/server.go:1966
default
2022-07-21t20:18:54.881346z2022/07/21 20:18:54.881 [1;35m[c][0m [panic.go:838] /usr/local/go/src/runtime/asm_amd64.s:1571
default
2022-07-21t20:18:54.881475z2022/07/21 20:18:54.881 [server.go:3195] [http] http: superfluous response.writeheader call from github.com/astaxie/beego/context.(*response).writeheader (context.go:230)
info
2022-07-21t20:18:54.882870zget2002.99 kb2 mschrome 103 https://beego-app-epcfdn7vua-uc.a.run.app/admin

[server.go:3195] [http] http：多余的响应。来自 github.com/astaxie/beego/context 的 writeheader 调用。(*response).writeheader (context.go:230)

根据我的搜索，这与多次写入标头有关，但我无法找到其来源。

main.go：

package main

import (
    _ "beego-app/routers"
    "net/http"

    "github.com/jinzhu/gorm"
    _ "github.com/jinzhu/gorm/dialects/sqlite"
    "github.com/qor/admin"

    web "github.com/astaxie/beego"
)

// define a gorm-backend model
type user struct {
    gorm.model
    name string
}

// define another gorm-backend model
type product struct {
    gorm.model
    name        string
    description string
}

func main() {
    // set up the database
    database, _ := gorm.open("sqlite3", "demo.db")
    database.automigrate(&user{}, &product{})

    // initalize
    admin := admin.new(&admin.adminconfig{db: database})

    // create resources from gorm-backend model
    admin.addresource(&user{})
    admin.addresource(&product{})

    // mount admin to the mux
    newmux := http.newservemux()
    admin.mountto("/admin", newmux)
    web.handler("/admin/*", newmux)
    web.run()
}

dockerfile：

FROM registry.semaphoreci.com/golang:1.18 as builder

ENV APP_HOME /go/src/beego-app

WORKDIR "$APP_HOME"
COPY / .

RUN go mod download
RUN go mod verify
RUN go build -o beego-app

FROM registry.semaphoreci.com/golang:1.18

ENV APP_HOME /go/src/beego-app
RUN mkdir -p "$APP_HOME"
WORKDIR "$APP_HOME"

COPY / .
COPY --from=builder "$APP_HOME"/beego-app $APP_HOME

EXPOSE 8080
CMD ["./beego-app"]

任何帮助将不胜感激。

正确答案

我自己解决了这个问题。我不完全理解为什么，但据我所知，Qor 不是使用 go 模块编写的，因此它抛出此错误，因为应用程序无法找到默认模板文件。

修复方法只是将 $GOPATH/pkg/mod/github.com/qor/qor/admin/views/ 复制到 $APP_DIR/app/views/qor/ ，以便应用程序可以访问模板文件.

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