今天学一下如何渲染获取到的数据
渲染 json, html, protobuf 的示例
渲染 json 的例子
/*
* Copyright 2022 CloudWeGo Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package main
import (
"context"
"github.com/cloudwego/hertz/pkg/common/utils"
"github.com/cloudwego/hertz/pkg/app"
"github.com/cloudwego/hertz/pkg/app/server"
"github.com/cloudwego/hertz/pkg/protocol/consts"
)
func main() {
h := server.Default(server.WithHostPorts("127.0.0.1:8080"))
// utils.H is a shortcut for map[string]interface{}
h.GET("/someJSON", func(ctx context.Context, c *app.RequestContext) {
c.JSON(consts.StatusOK, utils.H{"message": "hey", "status": consts.StatusOK})
})
h.GET("/moreJSON", func(ctx context.Context, c *app.RequestContext) {
// You also can use a struct
var msg struct {
Company string `json:"company"`
Location string
Number int
}
msg.Company = "company"
msg.Location = "location"
msg.Number = 123
// Note that msg.Company becomes "company" in the JSON
// Will output : {"company": "company", "Location": "location", "Number": 123}
c.JSON(consts.StatusOK, msg)
})
h.GET("/pureJson", func(ctx context.Context, c *app.RequestContext) {
c.PureJSON(consts.StatusOK, utils.H{
"html": "<p> Hello World </p>",
})
})
h.GET("/someData", func(ctx context.Context, c *app.RequestContext) {
c.Data(consts.StatusOK, "text/plain; charset=utf-8", []byte("hello"))
})
h.Spin()
}
这里面有三个 GET 请求，最有用的是第一个，里面自定义了一个 JSON 结构，然后打印一个 JSON 对象出来，默认的字段名都是大写字母开头，如果需要小写字母开头就要像 company 这个字段一样去设置。
渲染 html 的例子
我觉得这个例子和之前一天里面的有一点重复了，当时也渲染出来一个 HTML 文件。
/*
* Copyright 2022 CloudWeGo Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package main
import (
"context"
"fmt"
"html/template"
"net/http"
"time"
"github.com/cloudwego/hertz/pkg/app"
"github.com/cloudwego/hertz/pkg/app/server"
"github.com/cloudwego/hertz/pkg/common/utils"
)
func formatAsDate(t time.Time) string {
year, month, day := t.Date()
return fmt.Sprintf("%d/%02d/%02d", year, month, day)
}
func main() {
h := server.Default(server.WithHostPorts(":8080"))
h.Delims("{[{", "}]}")
h.SetFuncMap(template.FuncMap{
"formatAsDate": formatAsDate,
})
h.LoadHTMLGlob("render/html/*")
h.GET("/index", func(c context.Context, ctx *app.RequestContext) {
ctx.HTML(http.StatusOK, "index.tmpl", utils.H{
"title": "Main website",
})
})
h.GET("/raw", func(c context.Context, ctx *app.RequestContext) {
ctx.HTML(http.StatusOK, "template1.html", map[string]interface{}{
"now": time.Date(2017, 0o7, 0o1, 0, 0, 0, 0, time.UTC),
})
})
h.Spin()
}
然后配套的 index.tmpl 模板如下：
<html>
<h1>
{[{ .title }]}
</h1>
</html>
配套的 template1.html 如下：
<h1>Date: {[{.now | formatAsDate}]}</h1>
要运行的话还是：
go run render/html/main.go
然后访问 http://127.0.0.1:8080/index。
渲染 protobuf 的例子
目录里面的结构如下：
$ tree .
.
├── body
│ └── body.pb.go
├── README.md
├── body.proto
└── main.go
protobuf 的格式定义在 body.proto：
syntax = "proto2";
package body;
option go_package = "./body";
message BodyStruct {
optional bytes body = 1;
}
然后虚晃，还是需要 body.pb.go 文件，这里面定义格式：
// Code generated by protoc-gen-go. DO NOT EDIT.
// versions:
// protoc-gen-go v1.28.0
// protoc v3.19.4
// source: body.proto
package body
import (
protoreflect "google.golang.org/protobuf/reflect/protoreflect"
protoimpl "google.golang.org/protobuf/runtime/protoimpl"
reflect "reflect"
sync "sync"
)
const (
// Verify that this generated code is sufficiently up-to-date.
_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
// Verify that runtime/protoimpl is sufficiently up-to-date.
_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
)
type BodyStruct struct {
state protoimpl.MessageState
sizeCache protoimpl.SizeCache
unknownFields protoimpl.UnknownFields
Body []byte `protobuf:"bytes,1,opt,name=body" json:"body,omitempty"`
}
func (x *BodyStruct) Reset() {
*x = BodyStruct{}
if protoimpl.UnsafeEnabled {
mi := &file_body_proto_msgTypes[0]
ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
ms.StoreMessageInfo(mi)
}
}
func (x *BodyStruct) String() string {
return protoimpl.X.MessageStringOf(x)
}
func (*BodyStruct) ProtoMessage() {}
func (x *BodyStruct) ProtoReflect() protoreflect.Message {
mi := &file_body_proto_msgTypes[0]
if protoimpl.UnsafeEnabled && x != nil {
ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
if ms.LoadMessageInfo() == nil {
ms.StoreMessageInfo(mi)
}
return ms
}
return mi.MessageOf(x)
}
// Deprecated: Use BodyStruct.ProtoReflect.Descriptor instead.
func (*BodyStruct) Descriptor() ([]byte, []int) {
return file_body_proto_rawDescGZIP(), []int{0}
}
func (x *BodyStruct) GetBody() []byte {
if x != nil {
return x.Body
}
return nil
}
var File_body_proto protoreflect.FileDescriptor
var file_body_proto_rawDesc = []byte{
0x0a, 0x0a, 0x62, 0x6f, 0x64, 0x79, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x04, 0x62, 0x6f,
0x64, 0x79, 0x22, 0x20, 0x0a, 0x0a, 0x42, 0x6f, 0x64, 0x79, 0x53, 0x74, 0x72, 0x75, 0x63, 0x74,
0x12, 0x12, 0x0a, 0x04, 0x62, 0x6f, 0x64, 0x79, 0x18, 0x01, 0x20, 0x01, 0x28, 0x0c, 0x52, 0x04,
0x62, 0x6f, 0x64, 0x79, 0x42, 0x08, 0x5a, 0x06, 0x2e, 0x2f, 0x62, 0x6f, 0x64, 0x79,
}
var (
file_body_proto_rawDescOnce sync.Once
file_body_proto_rawDescData = file_body_proto_rawDesc
)
func file_body_proto_rawDescGZIP() []byte {
file_body_proto_rawDescOnce.Do(func() {
file_body_proto_rawDescData = protoimpl.X.CompressGZIP(file_body_proto_rawDescData)
})
return file_body_proto_rawDescData
}
var file_body_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
var file_body_proto_goTypes = []interface{}{
(*BodyStruct)(nil), // 0: body.BodyStruct
}
var file_body_proto_depIdxs = []int32{
0, // [0:0] is the sub-list for method output_type
0, // [0:0] is the sub-list for method input_type
0, // [0:0] is the sub-list for extension type_name
0, // [0:0] is the sub-list for extension extendee
0, // [0:0] is the sub-list for field type_name
}
func init() { file_body_proto_init() }
func file_body_proto_init() {
if File_body_proto != nil {
return
}
if !protoimpl.UnsafeEnabled {
file_body_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
switch v := v.(*BodyStruct); i {
case 0:
return &v.state
case 1:
return &v.sizeCache
case 2:
return &v.unknownFields
default:
return nil
}
}
}
type x struct{}
out := protoimpl.TypeBuilder{
File: protoimpl.DescBuilder{
GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
RawDescriptor: file_body_proto_rawDesc,
NumEnums: 0,
NumMessages: 1,
NumExtensions: 0,
NumServices: 0,
},
GoTypes: file_body_proto_goTypes,
DependencyIndexes: file_body_proto_depIdxs,
MessageInfos: file_body_proto_msgTypes,
}.Build()
File_body_proto = out.File
file_body_proto_rawDesc = nil
file_body_proto_goTypes = nil
file_body_proto_depIdxs = nil
}
接下来是 main.go：
/*
* Copyright 2022 CloudWeGo Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package main
import (
"context"
"github.com/cloudwego/hertz-examples/render/protobuf/body"
"github.com/cloudwego/hertz/pkg/app"
"github.com/cloudwego/hertz/pkg/app/server"
)
func main() {
h := server.Default(server.WithHostPorts(":8080"))
h.GET("/somePb", func(ctx context.Context, c *app.RequestContext) {
body := body.BodyStruct{
Body: []byte("Hello World"),
}
c.ProtoBuf(200, &body)
})
h.Spin()
}
要运行，先跑主函数代码起一个渲染的服务端：
go run render/protobuf/main.go
然后访问 http://127.0.0.1:8080/somePb。
目前没有研究明白，目测是把那份 raw 的数组解析成一段带什么 hello hertz protobuf 之类的对象。
