平台开发——openresy+lua 搭建文件上传服务

墨蓝 2023-02-25 02:15 9阅读 0赞

本文主要是介绍一种基于Openresty和Lua实现的文件上传服务器

# 第一步 #

配置openresty里面的nginx.conf

http { 
        include       mime.types;
        default_type  application/octet-stream;
        sendfile        on;
        keepalive_timeout  65;
    
        server { 
            listen       9001;
            server_name  localhost;
            
            location / { 
                root   html;         # /usr/local/openresty/nginx/html
                index  index.html index.htm;
            }
    
            location /upfile {                       #上传文件的地址http://localhost:9001/upfile
                content_by_lua_file myupload.lua;   # myupload.lua是我们接下来要写的文件上传服务lua文件，记得带上地址，比如：lua/myupload.lua
            }
    
            # redirect server error pages to the static page /50x.html
            error_page   500 502 503 504  /50x.html;
            location = /50x.html { 
                root   html;
            }
        }

# 第二步 #

编写一个简单的前端页面  
index.html 保存在9001端口 root 配置指令指定的文件系统目录(localhost:9001)下。

<!DOCTYPE html>
    <html>
    <head>
        <title>File upload example</title>
    </head>
    <body>
        <form action="upfile" method="post" enctype="multipart/form-data">
            <label for="testFileName">select file: </label>
            <input type="file" name="testFileName"/>
            <input type="submit" name="upload" value="Upload" />
        </form>
    </body>
    </html>

上面的“upfile”是上面conf配置的文件上传目录“location /upfile”

# 第三步 #

编写文件上传的lua脚本

-- myupload.lua
    
    --==========================================
    -- 文件上传
    --==========================================
    
    local upload = require "resty.upload"
    local cjson = require "cjson"
    
    local chunk_size = 4096
    local form, err = upload:new(chunk_size)
    if not form then
        ngx.log(ngx.ERR, "failed to new upload: ", err)
        ngx.exit(ngx.HTTP_INTERNAL_SERVER_ERROR)
    end
    
    form:set_timeout(1000)
    
    -- 字符串 split 分割
    string.split = function(s, p)
        local rt= { }
        string.gsub(s, '[^'..p..']+', function(w) table.insert(rt, w) end )
        return rt
    end
    
    -- 支持字符串前后 trim
    string.trim = function(s)
        return (s:gsub("^%s*(.-)%s*$", "%1"))
    end
    
    -- 文件保存的根路径
    local saveRootPath = "/home/local/openresty/nginx/upload/"
    
    -- 保存的文件对象
    local fileToSave
    
    --文件是否成功保存
    local ret_save = false
    
    while true do
        local typ, res, err = form:read()
        if not typ then
            ngx.say("failed to read: ", err)
            return
        end
    
        if typ == "header" then
            -- 开始读取 http header
            -- 解析出本次上传的文件名
            local key = res[1]
            local value = res[2]
            if key == "Content-Disposition" then
                -- 解析出本次上传的文件名
                -- form-data; name="testFileName"; filename="testfile.txt"
                local kvlist = string.split(value, ';')
                for _, kv in ipairs(kvlist) do
                    local seg = string.trim(kv)
                    if seg:find("filename") then
                        local kvfile = string.split(seg, "=")
                        local filename = string.sub(kvfile[2], 2, -2)
                        if filename then
                            fileToSave = io.open(saveRootPath .. filename, "w+")
                            if not fileToSave then
                                ngx.say("failed to open file ", filename)
                                return
                            end
                            break
                        end
                    end
                end
            end
        elseif typ == "body" then
            -- 开始读取 http body
            if fileToSave then
                fileToSave:write(res)
            end
        elseif typ == "part_end" then
            -- 文件写结束，关闭文件
            if fileToSave then
                fileToSave:close()
                fileToSave = nil
            end
            
            ret_save = true
        elseif typ == "eof" then
            -- 文件读取结束
            break
        else
            ngx.log(ngx.INFO, "do other things")
        end
    end
    
    if ret_save then
        ngx.say("save file ok")
    end

搭建完毕，现在可以进行测试：  
①浏览器登录“http://localhost:9001”进入前端页面，然后进行文件上传测试  
②利用postman进行post请求“http://localhost:9001/upfile”

本文绝大多数内容借鉴于：https://blog.51cto.com/quietmadman/1766034