Delete modules in case of breaking changes or invalid checksums, compatibility with go mod download (#10)

* add module invalidation via DELETE request
* add go mod download vcs provider

go.mod

@@ -1,13 +1,5 @@
 module github.com/sixt/gomodproxy
 
-require (
+go 1.13
-	github.com/emirpasic/gods v1.12.0 // indirect
+
-	github.com/pkg/errors v0.8.1 // indirect
+require gopkg.in/src-d/go-git.v4 v4.13.1
-	github.com/stretchr/testify v1.3.0 // indirect
-	golang.org/x/crypto v0.0.0-20190103213133-ff983b9c42bc // indirect
-	golang.org/x/net v0.0.0-20190110200230-915654e7eabc // indirect
-	golang.org/x/sys v0.0.0-20190109145017-48ac38b7c8cb // indirect
-	gopkg.in/src-d/go-billy.v4 v4.3.0 // indirect
-	gopkg.in/src-d/go-git-fixtures.v3 v3.3.0 // indirect
-	gopkg.in/src-d/go-git.v4 v4.8.1
-)

go.sum

@@ -1,68 +1,60 @@
-github.com/alcortesm/tgz v0.0.0-20161220082320-9c5fe88206d7 h1:uSoVVbwJiQipAclBbw+8quDsfcvFjOpI5iCf4p/cqCs=
 github.com/alcortesm/tgz v0.0.0-20161220082320-9c5fe88206d7/go.mod h1:6zEj6s6u/ghQa61ZWa/C2Aw3RkjiTBOix7dkqa1VLIs=
-github.com/anmitsu/go-shlex v0.0.0-20161002113705-648efa622239 h1:kFOfPq6dUM1hTo4JG6LR5AXSUEsOjtdm0kw0FtQtMJA=
 github.com/anmitsu/go-shlex v0.0.0-20161002113705-648efa622239/go.mod h1:2FmKhYUyUczH0OGQWaF5ceTx0UBShxjsH6f8oGKYe2c=
+github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5/go.mod h1:wHh0iHkYZB8zMSxRWpUBQtwG5a7fFgvEO+odwuTv2gs=
+github.com/creack/pty v1.1.7/go.mod h1:lj5s0c3V2DBrqTV7llrYr5NG6My20zk30Fl46Y7DoTY=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/emirpasic/gods v1.9.0/go.mod h1:YfzfFFoVP/catgzJb4IKIqXjX78Ha8FMSDh3ymbK86o=
 github.com/emirpasic/gods v1.12.0 h1:QAUIPSaCu4G+POclxeqb3F+WPpdKqFGlw36+yOzGlrg=
 github.com/emirpasic/gods v1.12.0/go.mod h1:YfzfFFoVP/catgzJb4IKIqXjX78Ha8FMSDh3ymbK86o=
-github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568 h1:BHsljHzVlRcyQhjrss6TZTdY2VfCqZPbv5k3iBFa2ZQ=
 github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568/go.mod h1:xEzjJPgXI435gkrCt3MPfRiAkVrwSbHsst4LCFVfpJc=
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-github.com/gliderlabs/ssh v0.1.1/go.mod h1:U7qILu1NlMHj9FlMhZLlkCdDnU1DBEAqr0aevW3Awn0=
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-github.com/google/go-cmp v0.2.0 h1:+dTQ8DZQJz0Mb/HjFlkptS1FeQ4cWSnN941F8aEG4SQ=
-github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99 h1:BQSFePA1RWJOlocH6Fxy8MmwDt+yVQYULKfN0RoTN8A=
 github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99/go.mod h1:1lJo3i6rXxKeerYnT8Nvf0QmHCRC1n8sfWVwXF2Frvo=
 github.com/jessevdk/go-flags v1.4.0/go.mod h1:4FA24M0QyGHXBuZZK/XkWh8h0e1EYbRYJSGM75WSRxI=
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 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
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 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
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-github.com/pelletier/go-buffruneio v0.2.0 h1:U4t4R6YkofJ5xHm3dJzuRpPZ0mr5MMCoAWooScCR7aA=
 github.com/pelletier/go-buffruneio v0.2.0/go.mod h1:JkE26KsDizTr40EUHkXVtNPvgGtbSNq5BcowyYOWdKo=
-github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
-github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
-github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sergi/go-diff v1.0.0 h1:Kpca3qRNrduNnOQeazBd0ysaKrUJiIuISHxogkT9RPQ=
 github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
 github.com/src-d/gcfg v1.4.0 h1:xXbNR5AlLSA315x2UO+fTSSAXCDf+Ar38/6oyGbDKQ4=
 github.com/src-d/gcfg v1.4.0/go.mod h1:p/UMsR43ujA89BJY9duynAwIpvqEujIH/jFlfL7jWoI=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
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-github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
-github.com/xanzy/ssh-agent v0.2.0 h1:Adglfbi5p9Z0BmK2oKU9nTG+zKfniSfnaMYB+ULd+Ro=
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-github.com/xanzy/ssh-agent v0.2.0/go.mod h1:0NyE30eGUDliuLEHJgYte/zncp2zdTStcOnWhgSqHD8=
+github.com/xanzy/ssh-agent v0.2.1/go.mod h1:mLlQY/MoOhWBj+gOGMQkOeiEvkx+8pJSI+0Bx9h2kr4=
-golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
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-golang.org/x/crypto v0.0.0-20190103213133-ff983b9c42bc h1:F5tKCVGp+MUAHhKp5MZtGqAlGX3+oCsiL1Q629FL90M=
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-golang.org/x/crypto v0.0.0-20190103213133-ff983b9c42bc/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
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-golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
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-golang.org/x/net v0.0.0-20190110200230-915654e7eabc/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
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-golang.org/x/sys v0.0.0-20180903190138-2b024373dcd9/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
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-golang.org/x/sys v0.0.0-20190109145017-48ac38b7c8cb/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
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-golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
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 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
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-gopkg.in/src-d/go-billy.v4 v4.3.0/go.mod h1:tm33zBoOwxjYHZIE+OV8bxTWFMJLrconzFMd38aARFk=
+gopkg.in/src-d/go-git-fixtures.v3 v3.5.0/go.mod h1:dLBcvytrw/TYZsNTWCnkNF2DSIlzWYqTe3rJR56Ac7g=
-gopkg.in/src-d/go-git-fixtures.v3 v3.1.1/go.mod h1:dLBcvytrw/TYZsNTWCnkNF2DSIlzWYqTe3rJR56Ac7g=
+gopkg.in/src-d/go-git.v4 v4.13.1 h1:SRtFyV8Kxc0UP7aCHcijOMQGPxHSmMOPrzulQWolkYE=
-gopkg.in/src-d/go-git-fixtures.v3 v3.3.0 h1:AxUOwLW3at53ysFqs0Lg+H+8KSQXl7AEHBvWj8wEsT8=
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-gopkg.in/src-d/go-git-fixtures.v3 v3.3.0/go.mod h1:dLBcvytrw/TYZsNTWCnkNF2DSIlzWYqTe3rJR56Ac7g=
-gopkg.in/src-d/go-git.v4 v4.8.1 h1:aAyBmkdE1QUUEHcP4YFCGKmsMQRAuRmUcPEQR7lOAa0=
-gopkg.in/src-d/go-git.v4 v4.8.1/go.mod h1:Vtut8izDyrM8BUVQnzJ+YvmNcem2J89EmfZYCkLokZk=
 gopkg.in/warnings.v0 v0.1.2 h1:wFXVbFY8DY5/xOe1ECiWdKCzZlxgshcYVNkBHstARME=
 gopkg.in/warnings.v0 v0.1.2/go.mod h1:jksf8JmL6Qr/oQM2OXTHunEvvTAsrWBLb6OOjuVWRNI=

pkg/api/api.go

@@ -158,6 +158,10 @@ func (api *api) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 				version = m[2]
 			}
 			module = decodeBangs(module)
+			if r.Method == http.MethodDelete && version != "" {
+				api.delete(w, r, module, version)
+				return
+			}
 			httpRequests.Add(route.id, 1)
 			defer func() {
 				v := &expvar.Float{}
@@ -179,7 +183,7 @@ func (api *api) vcs(ctx context.Context, module string) vcs.VCS {
 			return path.vcs(module)
 		}
 	}
-	return vcs.NewGit(api.log, api.gitdir, module, vcs.NoAuth())
+	return vcs.NewGoMod(api.log, module)
 }
 
 func (api *api) module(ctx context.Context, module string, version vcs.Version) ([]byte, time.Time, error) {
@@ -232,7 +236,7 @@ func (api *api) list(w http.ResponseWriter, r *http.Request, module, version str
 	if err != nil {
 		api.log("api.list", "module", module, "error", err)
 		httpErrors.Add(module, 1)
-		http.Error(w, err.Error(), http.StatusInternalServerError)
+		http.Error(w, err.Error(), http.StatusNotFound)
 		return
 	}
 
@@ -248,7 +252,7 @@ func (api *api) info(w http.ResponseWriter, r *http.Request, module, version str
 	if err != nil {
 		api.log("api.info", "module", module, "version", version, "error", err)
 		httpErrors.Add(module, 1)
-		http.Error(w, err.Error(), http.StatusInternalServerError)
+		http.Error(w, err.Error(), http.StatusNotFound)
 		return
 	}
 
@@ -283,8 +287,17 @@ func (api *api) zip(w http.ResponseWriter, r *http.Request, module, version stri
 	if err != nil {
 		api.log("api.zip", "module", module, "version", version, "error", err)
 		httpErrors.Add(module, 1)
-		http.Error(w, err.Error(), http.StatusInternalServerError)
+		http.Error(w, err.Error(), http.StatusNotFound)
 		return
 	}
 	io.Copy(w, bytes.NewReader(b))
 }
+
+func (api *api) delete(w http.ResponseWriter, r *http.Request, module, version string) {
+	for _, store := range api.stores {
+		if err := store.Del(r.Context(), module, vcs.Version(version)); err != nil {
+			http.Error(w, err.Error(), http.StatusNotFound)
+			return
+		}
+	}
+}

pkg/store/disk.go

@@ -47,4 +47,15 @@ func (d disk) Get(ctx context.Context, module string, version vcs.Version) (Snap
 	return s, err
 }
 
+func (d disk) Del(ctx context.Context, module string, version vcs.Version) error {
+	dir := string(d)
+	s := Snapshot{Module: module, Version: version}
+	err := os.Remove(filepath.Join(dir, s.Key()+".time"))
+	if err != nil {
+		return err
+	}
+	err = os.Remove(filepath.Join(dir, s.Key()+".zip"))
+	return err
+}
+
 func (d disk) Close() error { return nil }

pkg/store/mem.go

@@ -45,17 +45,41 @@ func (m *memory) Put(ctx context.Context, snapshot Snapshot) error {
 func (m *memory) Get(ctx context.Context, module string, version vcs.Version) (Snapshot, error) {
 	m.Lock()
 	defer m.Unlock()
-	return m.lookup(module, version)
+	item, err := m.lookup(module, version)
+	if err != nil {
+		return Snapshot{}, err
+	}
+	return item.Snapshot, nil
 }
 
-func (m *memory) lookup(module string, version vcs.Version) (Snapshot, error) {
+func (m *memory) Del(ctx context.Context, module string, version vcs.Version) error {
+	m.Lock()
+	defer m.Unlock()
+	item, err := m.lookup(module, version)
+	if err != nil {
+		return err
+	}
+	if item.prev == nil {
+		m.head = item.next
+	} else {
+		item.prev.next = item.next
+	}
+	if item.next == nil {
+		m.tail = item.prev
+	} else {
+		item.next.prev = item.prev
+	}
+	return nil
+}
+
+func (m *memory) lookup(module string, version vcs.Version) (*lruItem, error) {
 	for item := m.head; item != nil; item = item.next {
 		if item.Module == module && item.Version == version {
 			m.update(item)
-			return item.Snapshot, nil
+			return item, nil
 		}
 	}
-	return Snapshot{}, errors.New("not found")
+	return nil, errors.New("not found")
 }
 
 func (m *memory) insert(item *lruItem) {

pkg/store/store.go

@@ -14,6 +14,7 @@ type logger = func(...interface{})
 type Store interface {
 	Put(ctx context.Context, snapshot Snapshot) error
 	Get(ctx context.Context, module string, version vcs.Version) (Snapshot, error)
+	Del(ctx context.Context, module string, version vcs.Version) error
 	Close() error
 }
 

pkg/vcs/gomod.go

@@ -0,0 +1,87 @@
+package vcs
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type goVCS struct {
+	dir    string
+	log    logger
+	module string
+}
+
+func NewGoMod(l logger, module string) VCS {
+	return &goVCS{log: l, module: module, dir: "/tmp/_go"}
+}
+
+func (g *goVCS) List(ctx context.Context) ([]Version, error) {
+	if err := g.download(ctx, "latest"); err != nil {
+		return nil, err
+	}
+	b, err := g.file("list")
+	if err != nil {
+		return nil, err
+	}
+	versions := []Version{}
+	for _, line := range strings.Split(string(b), "\n") {
+		versions = append(versions, Version(line))
+	}
+	return versions, nil
+}
+
+func (g *goVCS) Timestamp(ctx context.Context, version Version) (time.Time, error) {
+	if err := g.download(ctx, version.String()); err != nil {
+		return time.Time{}, err
+	}
+	b, err := g.file(version.String() + ".info")
+	if err != nil {
+		return time.Time{}, err
+	}
+	info := struct {
+		Version string
+		Time    time.Time
+	}{}
+	if json.Unmarshal(b, &info) == nil {
+		return info.Time, nil
+	}
+	if t, err := time.Parse(time.RFC3339, string(b)); err == nil {
+		return t, nil
+	}
+	if sec, err := strconv.ParseInt(string(b), 10, 64); err == nil {
+		return time.Unix(sec, 0), nil
+	}
+	return time.Time{}, nil
+}
+
+func (g *goVCS) Zip(ctx context.Context, version Version) (io.ReadCloser, error) {
+	if err := g.download(ctx, version.String()); err != nil {
+		return nil, err
+	}
+	b, err := g.file(version.String() + ".zip")
+	if err != nil {
+		return nil, err
+	}
+	return ioutil.NopCloser(bytes.NewReader(b)), nil
+}
+
+func (g *goVCS) download(ctx context.Context, version string) error {
+	cmd := exec.Command("go", "mod", "download", g.module+"@"+version)
+	cmd.Env = append(os.Environ(), "GOPATH="+g.dir)
+	cmd.Stderr = os.Stderr
+	return cmd.Run()
+}
+
+func (g *goVCS) file(name string) ([]byte, error) {
+	path := filepath.Join(g.dir, "pkg", "mod", "cache", "download", g.module, "@v", name)
+	return ioutil.ReadFile(path)
+}