Registry: resolve dev packages

Also resolve @sap packages, but forward non-cds packages to default
registry

.registry/server.js

@@ -1,27 +1,34 @@
-const { exec } = require ('child_process')
+const { exec, execSync } = require ('child_process')
 const isWin = process.platform === 'win32'
 const express = require ('express')
 const fs = require ('fs')
+const { dirname, relative } = require('path')
+const axios = require('axios')
 const app = express()
 
-const { PORT=4444 } = process.env
-const [,,port=PORT,scope='@capire'] = process.argv
 const cwd = __dirname
+const port=process.env.PORT || 4444
+let scopes = process.argv.filter(a => a.startsWith('@'))
+if (!scopes.length)  scopes = ['@capire']
 
 // clean up on start (exit handler might not complete on Windows)
 exec(isWin ? 'del *.tgz' : 'rm *.tgz', {cwd})
 
 
-app.use('/-/:tarball', (req,res,next) => {
+app.use('/-/:tarball', async (req,res,next) => {
   console.debug ('GET', req.params)
   try {
     const { tarball } = req.params
     const pkgFull = tarball.substring(0, tarball.lastIndexOf('-'))
-    const [, pkg ] = /^\w+-(.+)/.exec(pkgFull)
+    const scope = '@'+pkgFull.substring(0, pkgFull.indexOf('-'))
+    const pkg = pkgFull.substring(pkgFull.indexOf('-')+1)
     fs.lstat(tarball,(err => {
-      if (err) console.debug (`npm pack ../${pkg}`)
-      if (err) exec(`npm pack ../${pkg}`,{cwd},next)
-      else next()
+      if (err) { // no tgz yet
+        const loc = dirname(require.resolve(`${scope}/${pkg}/package.json`))
+        console.debug (`npm pack ${relative(cwd, loc)}`)
+        exec(`npm pack ${loc}`,{cwd},next)
+      }
+      else next() //> express.static below
     }))
   } catch (e) {
     console.error(e)
@@ -31,14 +38,20 @@ app.use('/-/:tarball', (req,res,next) => {
 
 app.use('/-', express.static(__dirname))
 
-app.get('/*', (req,res)=>{
+app.get('/*', async (req,res)=>{
   const urlRegex = /^\/(@[\w-]+)\/(.+)/
   const url = decodeURIComponent(req.url)
   console.debug ('GET',url)
   try {
     if (!urlRegex.test(url))  return res.sendStatus(404)
     const [, scpe, pkg ] = urlRegex.exec(url)
-    const package = require (`${scpe}/${pkg}/package.json`)
+    const packageName = `${scpe}/${pkg}`
+
+    // delegate to default registry for @sap/non-cds packages
+    if (scpe === ('@sap') && !packageName.startsWith('@sap/cds')) {
+      return forward(req, res)
+    }
+    const package = require (`${packageName}/package.json`)
     const tarball = `${scpe.slice(1)}-${pkg}-${package.version}.tgz`
     // https://github.com/npm/registry/blob/master/docs/responses/package-metadata.md
     res.json({
@@ -53,6 +66,8 @@ app.get('/*', (req,res)=>{
           "dist": {
             "tarball": `${server.url}/-/${tarball}`
           },
+          dependencies: package.dependencies,
+          devDependencies: package.devDependencies
         }
       },
     })
@@ -64,15 +79,32 @@ app.get('/*', (req,res)=>{
 
 const server = app.listen(port, ()=>{
   const url = server.url = `http://localhost:${server.address().port}`
-  console.log (`npm set ${scope}:registry=${url}`)
-  exec(`npm set ${scope}:registry=${url}`)
-  console.log (`${scope} registry listening on ${url}`)
+
+  for (const scope of scopes) {
+    console.log (`npm set ${scope}:registry=${url}`)
+    execSync(`npm set ${scope}:registry=${url}`)
+  }
+  console.log (`registry listening on ${url}`)
 })
 
 
 const _exit = ()=>{
   server.close()
-  exec(`npm conf rm "${scope}:registry"`, ()=> { process.exit() })
+  for (const scope of scopes) {
+    execSync(`npm conf rm "${scope}:registry"`)
+  }
+  process.exit()
+}
+
+async function forward(req, res) {
+  try {
+    const url = `https://registry.npmjs.org${req.url}`
+    const resAxios = await axios.get(url)
+    console.debug('->', decodeURI(url), resAxios.status)
+    return res.json(resAxios.data)
+  } catch (e) {
+    return res.sendStatus(e.response.status)
+  }
 }
 
 process.on ('SIGTERM',_exit)