From 18338eb0d78c9ffbadd2d803b4e0b349b31b1e05 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C2=A0Ilya=20Atamas?= <stackdumper@gmail.com>
Date: Tue, 23 Apr 2019 15:36:51 +0300
Subject: [PATCH] feat: add tarballs caching

---
 cli/list.go     |  4 ++--
 cli/purge.go    |  4 ++--
 proxy/cache.go  | 23 ++++++++++++-----------
 proxy/server.go | 24 +++++++++++++++---------
 4 files changed, 31 insertions(+), 24 deletions(-)

diff --git a/cli/list.go b/cli/list.go
index 17e765d..d147a3c 100644
--- a/cli/list.go
+++ b/cli/list.go
@@ -10,7 +10,7 @@ import (
 // start a server
 var listCmd = &cobra.Command{
 	Use:   "list",
-	Short: "List all cached packages",
+	Short: "List all cached paths",
 	Run: func(cmd *cobra.Command, args []string) {
 		proxy := getProxy(func() (npmproxy.Options, error) {
 			return npmproxy.Options{
@@ -18,7 +18,7 @@ var listCmd = &cobra.Command{
 			}, nil
 		})
 
-		metadatas, err := proxy.ListMetadata()
+		metadatas, err := proxy.ListCachedPaths()
 		if err != nil {
 			panic(err)
 		}
diff --git a/cli/purge.go b/cli/purge.go
index 9f52f80..f24bfd8 100644
--- a/cli/purge.go
+++ b/cli/purge.go
@@ -8,7 +8,7 @@ import (
 // start a server
 var purgeCmd = &cobra.Command{
 	Use:   "purge",
-	Short: "Purge all cached packages",
+	Short: "Purge all cached paths",
 	Run: func(cmd *cobra.Command, args []string) {
 		proxy := getProxy(func() (npmproxy.Options, error) {
 			return npmproxy.Options{
@@ -16,7 +16,7 @@ var purgeCmd = &cobra.Command{
 			}, nil
 		})
 
-		err := proxy.PurgeMetadata()
+		err := proxy.PurgeCachedPaths()
 		if err != nil {
 			panic(err)
 		}
diff --git a/proxy/cache.go b/proxy/cache.go
index 1848e90..e56de0f 100644
--- a/proxy/cache.go
+++ b/proxy/cache.go
@@ -5,17 +5,18 @@ import (
 	"io/ioutil"
 	"log"
 	"net/http"
+	"regexp"
 	"strings"
 )
 
-// GetMetadata returns cached NPM response for a given package path.
-func (proxy Proxy) GetMetadata(name string, originalPath string, request *http.Request) ([]byte, error) {
+// GetCachedPath returns cached upstream response for a given url path.
+func (proxy Proxy) GetCachedPath(path string, request *http.Request) ([]byte, error) {
 	options, err := proxy.GetOptions()
 	if err != nil {
 		return nil, err
 	}
 
-	key := options.DatabasePrefix + name
+	key := options.DatabasePrefix + path
 
 	// get package from database
 	pkg, err := proxy.Database.Get(key)
@@ -31,7 +32,7 @@ func (proxy Proxy) GetMetadata(name string, originalPath string, request *http.R
 
 		// error is caused by nonexistent package
 		// fetch package
-		req, err := http.NewRequest("GET", options.UpstreamAddress+originalPath, nil)
+		req, err := http.NewRequest("GET", options.UpstreamAddress+path, nil)
 
 		req.Header = request.Header
 		req.Header.Set("Accept-Encoding", "gzip")
@@ -66,15 +67,15 @@ func (proxy Proxy) GetMetadata(name string, originalPath string, request *http.R
 		}
 	}
 
-	// replace tarball urls
-	// FIXME: unmarshall and replace only necessary fields
-	// convertedPkg := strings.ReplaceAll(string(pkg), options.ReplaceAddress, options.StaticServerAddress)
+	// TODO: avoid calling MustCompile every time
+	// find "dist": "https?://.*/ and replace to "dist": "{localurl}/
+	pkg = regexp.MustCompile(`(?U)"tarball":"https?://.*/`).ReplaceAllString(pkg, `"dist": "http://localhost:8080/`)
 
 	return []byte(pkg), nil
 }
 
-// ListMetadata returns list of all cached packages
-func (proxy Proxy) ListMetadata() ([]string, error) {
+// ListCachedPaths returns list of all cached url paths.
+func (proxy Proxy) ListCachedPaths() ([]string, error) {
 	options, err := proxy.GetOptions()
 	if err != nil {
 		return nil, err
@@ -93,8 +94,8 @@ func (proxy Proxy) ListMetadata() ([]string, error) {
 	return deprefixedMetadata, nil
 }
 
-// PurgeMetadata deletes all cached packages.
-func (proxy Proxy) PurgeMetadata() error {
+// PurgeCachedPaths deletes all cached url paths.
+func (proxy Proxy) PurgeCachedPaths() error {
 	options, err := proxy.GetOptions()
 	if err != nil {
 		return err
diff --git a/proxy/server.go b/proxy/server.go
index fc917c3..2f98b67 100644
--- a/proxy/server.go
+++ b/proxy/server.go
@@ -2,6 +2,7 @@ package proxy
 
 import (
 	"net/http"
+	"strings"
 	"time"
 
 	ginzap "github.com/gin-contrib/zap"
@@ -32,14 +33,7 @@ func (proxy Proxy) Server(options ServerOptions) *http.Server {
 }
 
 func (proxy Proxy) getPackageHandler(c *gin.Context) {
-	var name string
-	if c.Param("name") != "" {
-		name = c.Param("scope") + "/" + c.Param("name")
-	} else {
-		name = c.Param("scope")
-	}
-
-	pkg, err := proxy.GetMetadata(name, c.Request.URL.Path, c.Request)
+	pkg, err := proxy.GetCachedPath(c.Request.URL.Path, c.Request)
 
 	if err != nil {
 		c.AbortWithError(500, err)
@@ -49,8 +43,20 @@ func (proxy Proxy) getPackageHandler(c *gin.Context) {
 	}
 }
 
+func (proxy Proxy) getTarballHabdler(c *gin.Context) {
+	pkg, err := proxy.GetCachedPath(c.Request.URL.Path, c.Request)
+
+	if err != nil {
+		c.AbortWithError(500, err)
+	} else {
+		c.Data(200, "application/json", pkg)
+	}
+}
+
 func (proxy Proxy) noRouteHandler(c *gin.Context) {
-	if c.Request.URL.Path == "/" {
+	if strings.Contains(c.Request.URL.Path, ".tgz") {
+		proxy.getTarballHabdler(c)
+	} else if c.Request.URL.Path == "/" {
 		err := proxy.Database.Health()
 
 		if err != nil {