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Diffstat (limited to 'tools/nixery/server/main.go')
-rw-r--r-- | tools/nixery/server/main.go | 248 |
1 files changed, 0 insertions, 248 deletions
diff --git a/tools/nixery/server/main.go b/tools/nixery/server/main.go deleted file mode 100644 index 6ae0730906dc..000000000000 --- a/tools/nixery/server/main.go +++ /dev/null @@ -1,248 +0,0 @@ -// Copyright 2019 Google LLC -// -// Licensed under the Apache License, Version 2.0 (the "License"); you may not -// use this file except in compliance with the License. You may obtain a copy of -// the License at -// -// https://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT -// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the -// License for the specific language governing permissions and limitations under -// the License. - -// The nixery server implements a container registry that transparently builds -// container images based on Nix derivations. -// -// The Nix derivation used for image creation is responsible for creating -// objects that are compatible with the registry API. The targeted registry -// protocol is currently Docker's. -// -// When an image is requested, the required contents are parsed out of the -// request and a Nix-build is initiated that eventually responds with the -// manifest as well as information linking each layer digest to a local -// filesystem path. -package main - -import ( - "encoding/json" - "fmt" - "io/ioutil" - "net/http" - "regexp" - - "github.com/google/nixery/server/builder" - "github.com/google/nixery/server/config" - "github.com/google/nixery/server/layers" - "github.com/google/nixery/server/storage" - log "github.com/sirupsen/logrus" -) - -// ManifestMediaType is the Content-Type used for the manifest itself. This -// corresponds to the "Image Manifest V2, Schema 2" described on this page: -// -// https://docs.docker.com/registry/spec/manifest-v2-2/ -const manifestMediaType string = "application/vnd.docker.distribution.manifest.v2+json" - -// This variable will be initialised during the build process and set -// to the hash of the entire Nixery source tree. -var version string = "devel" - -// Regexes matching the V2 Registry API routes. This only includes the -// routes required for serving images, since pushing and other such -// functionality is not available. -var ( - manifestRegex = regexp.MustCompile(`^/v2/([\w|\-|\.|\_|\/]+)/manifests/([\w|\-|\.|\_]+)$`) - layerRegex = regexp.MustCompile(`^/v2/([\w|\-|\.|\_|\/]+)/blobs/sha256:(\w+)$`) -) - -// Downloads the popularity information for the package set from the -// URL specified in Nixery's configuration. -func downloadPopularity(url string) (layers.Popularity, error) { - resp, err := http.Get(url) - if err != nil { - return nil, err - } - - if resp.StatusCode != 200 { - return nil, fmt.Errorf("popularity download from '%s' returned status: %s\n", url, resp.Status) - } - - j, err := ioutil.ReadAll(resp.Body) - if err != nil { - return nil, err - } - - var pop layers.Popularity - err = json.Unmarshal(j, &pop) - if err != nil { - return nil, err - } - - return pop, nil -} - -// Error format corresponding to the registry protocol V2 specification. This -// allows feeding back errors to clients in a way that can be presented to -// users. -type registryError struct { - Code string `json:"code"` - Message string `json:"message"` -} - -type registryErrors struct { - Errors []registryError `json:"errors"` -} - -func writeError(w http.ResponseWriter, status int, code, message string) { - err := registryErrors{ - Errors: []registryError{ - {code, message}, - }, - } - json, _ := json.Marshal(err) - - w.WriteHeader(status) - w.Header().Add("Content-Type", "application/json") - w.Write(json) -} - -type registryHandler struct { - state *builder.State -} - -func (h *registryHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) { - // Acknowledge that we speak V2 with an empty response - if r.RequestURI == "/v2/" { - return - } - - // Serve the manifest (straight from Nix) - manifestMatches := manifestRegex.FindStringSubmatch(r.RequestURI) - if len(manifestMatches) == 3 { - imageName := manifestMatches[1] - imageTag := manifestMatches[2] - - log.WithFields(log.Fields{ - "image": imageName, - "tag": imageTag, - }).Info("requesting image manifest") - - image := builder.ImageFromName(imageName, imageTag) - buildResult, err := builder.BuildImage(r.Context(), h.state, &image) - - if err != nil { - writeError(w, 500, "UNKNOWN", "image build failure") - - log.WithError(err).WithFields(log.Fields{ - "image": imageName, - "tag": imageTag, - }).Error("failed to build image manifest") - - return - } - - // Some error types have special handling, which is applied - // here. - if buildResult.Error == "not_found" { - s := fmt.Sprintf("Could not find Nix packages: %v", buildResult.Pkgs) - writeError(w, 404, "MANIFEST_UNKNOWN", s) - - log.WithFields(log.Fields{ - "image": imageName, - "tag": imageTag, - "packages": buildResult.Pkgs, - }).Warn("could not find Nix packages") - - return - } - - // This marshaling error is ignored because we know that this - // field represents valid JSON data. - manifest, _ := json.Marshal(buildResult.Manifest) - w.Header().Add("Content-Type", manifestMediaType) - w.Write(manifest) - return - } - - // Serve an image layer. For this we need to first ask Nix for - // the manifest, then proceed to extract the correct layer from - // it. - layerMatches := layerRegex.FindStringSubmatch(r.RequestURI) - if len(layerMatches) == 3 { - digest := layerMatches[2] - storage := h.state.Storage - err := storage.ServeLayer(digest, r, w) - if err != nil { - log.WithError(err).WithFields(log.Fields{ - "layer": digest, - "backend": storage.Name(), - }).Error("failed to serve layer from storage backend") - } - - return - } - - log.WithField("uri", r.RequestURI).Info("unsupported registry route") - - w.WriteHeader(404) -} - -func main() { - cfg, err := config.FromEnv() - if err != nil { - log.WithError(err).Fatal("failed to load configuration") - } - - var s storage.Backend - - switch cfg.Backend { - case config.GCS: - s, err = storage.NewGCSBackend() - case config.FileSystem: - s, err = storage.NewFSBackend() - } - if err != nil { - log.WithError(err).Fatal("failed to initialise storage backend") - } - - log.WithField("backend", s.Name()).Info("initialised storage backend") - - cache, err := builder.NewCache() - if err != nil { - log.WithError(err).Fatal("failed to instantiate build cache") - } - - var pop layers.Popularity - if cfg.PopUrl != "" { - pop, err = downloadPopularity(cfg.PopUrl) - if err != nil { - log.WithError(err).WithField("popURL", cfg.PopUrl). - Fatal("failed to fetch popularity information") - } - } - - state := builder.State{ - Cache: &cache, - Cfg: cfg, - Pop: pop, - Storage: s, - } - - log.WithFields(log.Fields{ - "version": version, - "port": cfg.Port, - }).Info("starting Nixery") - - // All /v2/ requests belong to the registry handler. - http.Handle("/v2/", ®istryHandler{ - state: &state, - }) - - // All other roots are served by the static file server. - webDir := http.Dir(cfg.WebDir) - http.Handle("/", http.FileServer(webDir)) - - log.Fatal(http.ListenAndServe(":"+cfg.Port, nil)) -} |