ec-router
Version:
一个koa2自动路由中间件，直接根椐请求方法及路径路由到指定的controller。无需人工编写路由表或映射
202 lines (191 loc) • 8.15 kB
JavaScript
/**
* ec-Router
* @Author: Tim<tim8670@gmail.com>
* An auto & easy router for koa2
*/
const log = require('./log')
const controller = require('./controller')
const fs = require('fs');
//default config
let config = {
/**
* route type
* 1(default) [RESTful] -- [GET/POST/PUT/DELETE] /uriPrefix/resourceName/[resourceId]
* 2 [Path] -- /uriPrefix/controllerName/actionName
* 3 [QueryString] -- /uriPrefix/uriApiName?c=controllerName&a=actionName (use uriCParam,uriAParam set param key)
*/
type : 1,
uriApiName : 'index',
uriCParam : 'c',
uriAParam : 'a',
uriPrefix : '', //start with "/",or empty string
uriDefault : '/index',
apiVer : false, //api version required ?
apiVeRegex : /^v?(\d){1,2}(\.[\d]{1,2})?$/, //api version regex
controllerPath : 'controllers', //set controller files path (relative app root), default is 'controllers'
allowMethod : ['get','post','put','delete','options'],
hotLoad : true
}
class EcRouter {
constructor(){}
//modify default config
setConfig(conf){
log.d("--setConfig--")
for(let c in conf){
if(config[c] != undefined){
let val = conf[c]
if(c == 'allowMethod'){
val = []
for(let m in conf.allowMethod){
val.push(conf.allowMethod[m].toLowerCase())
}
}
config[c] = val
}
}
log.d(config)
}
//hotLoad
loadConfig(cf){
log.d('--loadConfig--')
let conf = require(cf)
let setConfig = this.setConfig
setConfig(conf)
//to be fix: will call twice on win
if(config.hotLoad){
fs.watch(cf, (event,filename) => {
log.d('--config hot reload--')
try{
if(event !== 'change'){
throw new Error(event+" event,skip...")
}
let path = require.resolve(cf);
require.cache[path] && (require.cache[path] = null);
conf = require(cf)
setConfig(conf)
}catch(e){
log.d('[err] loadConfig fail, '+ e.toString())
}
})
}
}
// dispatch route, koa2 middleware method
dispatcher(){
log.d("--dispatcher--")
if([1,2,3].indexOf(config.type) == -1){ //not supported type,throw error
throw new Error('route type unexpected');
}
let apiVerRegex = null
let cDir = process.cwd() + '/'+ config.controllerPath;
let cFiles = controller.load(cDir)
//hot load
if(config.hotLoad){
fs.watch(cDir, {recursive:true}, (event,filename) => {
log.d('--controller hot reload--')
try{
cFiles = controller.load(cDir)
}catch(e){
log.d('[err] loadController fail, '+ e.toString())
}
})
}
let controllers = cFiles
return async (ctx, next) => {
log.d("--on request--")
log.d(config)
try{
let uri = ctx.request.path == '/' ? config.uriDefault : ctx.request.path
let reqMethod = ctx.request.method.toLowerCase()
log.d({method:reqMethod,uri:uri})
if(config.allowMethod.indexOf(reqMethod) == -1){
log.d("method not allowed")
throw {code:405,error:'method '+reqMethod+ ' not allowed'}
}
if(reqMethod == 'options'){ //_hook not load yet
ctx.status = 204
await next()
return
}
if(config.uriPrefix != ''){ //remove prefix if uriPrefix not empty
if(uri.indexOf(config.uriPrefix) !== 0){ //404 prefix not found
log.d('uri prefix not exists -- '+ config.uriPrefix)
throw {code:404,error:'Not Found: uri prefix not exists'}
}else{
uri = uri.replace(config.uriPrefix,'')
}
}
let path = uri.split("/")
let apiVer = ''
path.shift()
if(config.apiVer && config.apiVeRegex){
if(!config.apiVeRegex.test(path[0])){
log.d("api version not match")
throw {code:404,error:'Not Found: api version not match'}
}
//test ok
apiVer = path.shift()
if(!cFiles[apiVer]){
log.d("this version api not found")
throw {code:404,error:'Not Found: api version not exists'}
}
controllers = cFiles[apiVer]
}
log.d('api ver = '+apiVer)
let [resource, action] = path
let resourceId = 0
if(config.type == 1){
log.d('--RESTful route--')
log.d({res:resource,resId:action,action:reqMethod})
resourceId = action || 0
ctx.req.resourceId = resourceId //set resourceId
ctx.req.resource = resource //set resource
action = reqMethod
} else if(config.type == 3){ //querystring,reParse resource,action
if(path.length != 1 || resource != config.uriApiName){
log.d('api name not exists -- '+ config.uriApiName)
throw {code:404,error:'Not Found: miss api name'}
}
let params = ctx.request.query
resource = params[config.uriCParam] || ''
action = params[config.uriAParam] || ''
}
ctx.ecRouter = {resource,action,resourceId}
let c = controllers[resource] || controllers['_any']
if(c != undefined){
log.d("found controller file: "+ ( controllers[resource]? resource: '_any'))
if(c[action] || c._any){
if(!c[action]){ //not action,match "all"
log.d('forward to action: _any')
action = '_any'
}
log.d("route ok")
log.d({controller:resource,action:action})
if(controllers['_hook'].before){ //hook before
log.d('--onbefore controller--')
await controllers['_hook'].before(ctx)
}
log.d('--call controller action--')
await c[action](ctx)
if(controllers['_hook'].after){ //hook after
log.d('--onafter controller--')
await controllers['_hook'].after(ctx)
}
await next()
log.d('--request finished--')
return
}
}
throw {code:404,error:'Not Found: controller or action not found'}
} catch(err) {
log.d('exception: '+err)
if(controllers['_hook'].error){
await controllers['_hook'].error(ctx,err)
}
await next()
log.d('--request finished--')
return
}
}
}
}
module.exports = new EcRouter()