protobufjs 配置踩坑记录

本文主要是小程序使用PB协议，以下时博主遇到的问题以及解决办法。

1、安装protobufjs

npm install --save protobufjs

注意：我之前也使用过 npm install -g protobufjs去安装，但是出现以下的问题，关键是我使用sudo 清除相关文件之后还是有问题，心累啊！！！！

npm ERR! code EACCES
npm ERR! syscall mkdir
npm ERR! path /usr/local/lib/node_modules/protobufjs
npm ERR! errno -13
npm ERR! Error: EACCES: permission denied, mkdir '/usr/local/lib/node_modules/protobufjs'
npm ERR!  [Error: EACCES: permission denied, mkdir '/usr/local/lib/node_modules/protobufjs'] {
npm ERR!   errno: -13,
npm ERR!   code: 'EACCES',
npm ERR!   syscall: 'mkdir',
npm ERR!   path: '/usr/local/lib/node_modules/protobufjs'
npm ERR! }
npm ERR! 
npm ERR! The operation was rejected by your operating system.
npm ERR! It is likely you do not have the permissions to access this file as the current user
npm ERR! 
npm ERR! If you believe this might be a permissions issue, please double-check the
npm ERR! permissions of the file and its containing directories, or try running
npm ERR! the command again as root/Administrator.

遇到以上的报错信息运行，强制清楚

sudo chown -R $(whoami) $(npm config get prefix)/{lib/node_modules,bin,share}

之后再安装即可

2、查看是否安装成功

npm list protobufjs

运行命令，之后查看protobufjs版本号，出现版本信息即为安装成功

3、运行pbjs

protobufjs安装成功之后，运行pbjs，结果出现command not found: pbjs，然后大家可以试一下

npx pbjs

然后会出现，哇哦，我总遇看到了胜利的希望，感恩啊！！！！！

Translates between file formats and generates static code.-t, --target     Specifies the target format. Also accepts a path to require a custom target.json          JSON representationjson-module   JSON representation as a moduleproto2        Protocol Buffers, Version 2proto3        Protocol Buffers, Version 3static        Static code without reflection (non-functional on its own)static-module Static code without reflection as a module-p, --path       Adds a directory to the include path.-o, --out        Saves to a file instead of writing to stdout.--sparse         Exports only those types referenced from a main file (experimental).Module targets only:-w, --wrap       Specifies the wrapper to use. Also accepts a path to require a custom wrapper.default   Default wrapper supporting both CommonJS and AMDcommonjs  CommonJS wrapperamd       AMD wrapperes6       ES6 wrapper (implies --es6)closure   A closure adding to protobuf.roots where protobuf is a global--dependency     Specifies which version of protobuf to require. Accepts any valid module id-r, --root       Specifies an alternative protobuf.roots name.-l, --lint       Linter configuration. Defaults to protobuf.js-compatible rules:eslint-disable block-scoped-var, id-length, no-control-regex, no-magic-numbers, no-prototype-builtins, no-redeclare, no-shadow, no-var, sort-vars--es6            Enables ES6 syntax (const/let instead of var)Proto sources only:--keep-case      Keeps field casing instead of converting to camel case.Static targets only:--no-create      Does not generate create functions used for reflection compatibility.--no-encode      Does not generate encode functions.--no-decode      Does not generate decode functions.--no-verify      Does not generate verify functions.--no-convert     Does not generate convert functions like from/toObject--no-delimited   Does not generate delimited encode/decode functions.--no-beautify    Does not beautify generated code.--no-comments    Does not output any JSDoc comments.--force-long     Enfores the use of 'Long' for s-/u-/int64 and s-/fixed64 fields.--force-number   Enfores the use of 'number' for s-/u-/int64 and s-/fixed64 fields.--force-message  Enfores the use of message instances instead of plain objects.usage: pbjs [options] file1.proto file2.json ...  (or pipe)  other | pbjs [options] -

4、使用pbjs 转换一下.proto文件

最后一步来啦，这里需要注意一下，如果你的.proto没有放到根目录的时候，需要找到相对应的文件夹在运行，如果.proto在根目录直接运行即可

npx pbjs -t json awesome.proto > awesome.json

 // awesome.protosyntax = "proto3";message AwesomeMessage {string awesome_field = 1; // becomes awesomeField}

然后你就会发现得到一个awesome.json文件，

 {"nested": {"AwesomeMessage": {"fields": {"awesomeField": {"type": "string","id": 1}}}}}

但此时的json文件我们不能直接使用，不过我们可以将json对象取出放到小程序项目当中去，比如在小程序项目中新建一个awesome.js，内容为

 module.exports = {"nested": {"AwesomeMessage": {"fields": {"awesomeField": {"type": "string","id": 1}}}}};

然后，大功告成，总于可以愉快的使用protobufjs 啦。最后，如果.proto文件内容更新，需要重复步骤四更新js文件哦