initial

.gitignore

+vendor

Dockerfile

+FROM golang:1.9 AS build
+
+RUN curl https://raw.githubusercontent.com/golang/dep/master/install.sh | sh
+
+WORKDIR /go/src/gitlab.ssec.wisc.edu/brucef/chart-server
+COPY . .
+RUN dep ensure && ./build.sh
+
+
+FROM debian:buster-slim
+COPY --from=build /go/bin/chart-server .
+ENTRYPOINT ["./chart-server"]
+CMD ["$@"]

Gopkg.lock

+# This file is autogenerated, do not edit; changes may be undone by the next 'dep ensure'.
+
+
+[[projects]]
+  name = "github.com/pkg/errors"
+  packages = ["."]
+  revision = "645ef00459ed84a119197bfb8d8205042c6df63d"
+  version = "v0.8.0"
+
+[[projects]]
+  name = "github.com/spf13/pflag"
+  packages = ["."]
+  revision = "9a97c102cda95a86cec2345a6f09f55a939babf5"
+  version = "v1.0.2"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-digest = "6a5cb0d32267ee88743a8972ec6d5c53e95e1e90a4711815b803c569c22340b6"
+  solver-name = "gps-cdcl"
+  solver-version = 1

Gopkg.toml

+# Gopkg.toml example
+#
+# Refer to https://github.com/golang/dep/blob/master/docs/Gopkg.toml.md
+# for detailed Gopkg.toml documentation.
+#
+# required = ["github.com/user/thing/cmd/thing"]
+# ignored = ["github.com/user/project/pkgX", "bitbucket.org/user/project/pkgA/pkgY"]
+#
+# [[constraint]]
+#   name = "github.com/user/project"
+#   version = "1.0.0"
+#
+# [[constraint]]
+#   name = "github.com/user/project2"
+#   branch = "dev"
+#   source = "github.com/myfork/project2"
+#
+# [[override]]
+#   name = "github.com/x/y"
+#   version = "2.4.0"
+#
+# [prune]
+#   non-go = false
+#   go-tests = true
+#   unused-packages = true
+
+
+[[constraint]]
+  name = "github.com/pkg/errors"
+  version = "0.8.0"
+
+[[constraint]]
+  name = "github.com/spf13/pflag"
+  version = "1.0.2"
+
+[prune]
+  go-tests = true
+  unused-packages = true

build.sh

+#!/usr/bin/env bash
+ver=$(git describe)
+sha=$(git rev-parse HEAD)
+dt="$(date +%Y-%m-%d)T$(date +%H:%M:%S)Z"
+buildStr="v${ver} (${dt})"
+pkg=gitlab.ssec.wisc.edu/brucef/chart-server
+go install --ldflags "-X 'main.buildStr=${buildStr}'" ${pkg}/...

main.go

+package main // import "gitlab.ssec.wisc.edu/brucef/chart-server"
+
+import (
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"os/exec"
+	"path"
+
+	"github.com/pkg/errors"
+	"github.com/spf13/pflag"
+)
+
+func updateIndex() error {
+	cmd := exec.Command("helm", "repo", "index", "--url", url, dir)
+	cmd.Stderr = os.Stderr
+	err := cmd.Run()
+	if err != nil {
+		return errors.Wrapf(err, "running helm")
+	}
+	return nil
+}
+
+func handleUpload(w http.ResponseWriter, r *http.Request) {
+	p := path.Join(dir, r.URL.Path)
+	st, err := os.Stat(p)
+	// got an error and the file exists... something interesting perhaps?
+	if err != nil && !os.IsNotExist(err) {
+		log.Printf("ERROR: could not stat %s : %s\n", p, err)
+		http.Error(w, "InternalServerError", http.StatusInternalServerError)
+		return
+	}
+	// got a stat result, file must exist
+	if st != nil {
+		http.Error(w, "File exists", http.StatusForbidden)
+		return
+	}
+
+	// file does not exist, proceed with upload
+	f, err := os.Create(p)
+	if err != nil {
+		log.Printf("InternalServerErrror: could not create %s: %s\n", p, err)
+		http.Error(w, "Could not complete upload", http.StatusInternalServerError)
+		return
+	}
+	if _, err := io.Copy(f, r.Body); err != nil {
+		log.Printf("InternalServerErrror: could not copy %s: %s\n", p, err)
+		http.Error(w, "Could not complete upload", http.StatusInternalServerError)
+		return
+	}
+
+	err = updateIndex()
+	if err != nil {
+		log.Printf("ERROR updating index: %s\n", err)
+		http.Error(w, "Could not update index", http.StatusInternalServerError)
+		// best-effort to remove the file if we could not update the index
+		os.Remove(p)
+		return
+	}
+	log.Printf("successfully handled chart %s", path.Base(p))
+}
+
+func handleGet(w http.ResponseWriter, r *http.Request) {
+	p := path.Join(dir, r.URL.Path)
+	if st, err := os.Stat(p); os.IsNotExist(err) || st.IsDir() {
+		http.Error(w, "Not Found", http.StatusNotFound)
+		return
+	}
+	f, err := os.Open(p)
+	if err != nil {
+		log.Printf("InternalServerErrror: could not open %s: %s\n", p, err)
+		http.Error(w, "InternalServerError", http.StatusInternalServerError)
+		return
+	}
+	if _, err := io.Copy(w, f); err != nil {
+		log.Printf("InternalServerErrror: could not copy %s: %s\n", p, err)
+		http.Error(w, "InternalServerError", http.StatusInternalServerError)
+		return
+	}
+}
+
+func handle(w http.ResponseWriter, r *http.Request) {
+	switch r.Method {
+	case "PUT":
+		handleUpload(w, r)
+	case "GET":
+		handleGet(w, r)
+	default:
+		http.Error(w, "Bad Request", http.StatusBadRequest)
+	}
+}
+
+func handleStatus(w http.ResponseWriter, r *http.Request) {
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte("OK!\n"))
+}
+
+func getEnvDefault(name, def string) string {
+	if v, ok := os.LookupEnv(name); ok {
+		return v
+	}
+	return def
+}
+
+var (
+	dir      string
+	host     string
+	url      string
+	buildStr string
+)
+
+func main() {
+	pflag.ErrHelp = errors.New("")
+	pflag.Usage = func() {
+		fmt.Fprintf(os.Stderr, `USAGE %s [options]
+
+Helm chart server that only accepts PUT requests to upload charts and GET
+requests to download them. Whenever a chart is successfully uploaded the index
+will be updated. This requires a working helm client installation and the helm
+binary on the current PATH. Most helm options, if they need to be set can be
+set via the $HELM_* environment variables.
+
+Options can also be specified as environment variables $CHART_SVR_<name>
+
+`, os.Args[0])
+
+		pflag.PrintDefaults()
+
+		fmt.Fprintf(os.Stderr, "\n%s\n", buildStr)
+	}
+	pflag.StringVar(&dir, "dir", getEnvDefault("CHART_SVR_DIR", "."), "Chart report dir")
+	pflag.StringVar(&host, "host", getEnvDefault("CHART_SVR_HOST", ":8080"), "Host to bind to [<host>]:<port>")
+	pflag.StringVar(&url, "url", getEnvDefault("CHART_SVR_URL", ""), "URL to the chart repository")
+	pflag.Parse()
+
+	if len(url) == 0 {
+		fmt.Fprintf(os.Stderr, "either --url or CHART_SVR_URL is required\n")
+		os.Exit(1)
+	}
+
+	if !path.IsAbs(dir) {
+		p, err := os.Getwd()
+		if err != nil {
+			panic(err)
+		}
+		dir = path.Join(p, dir)
+	}
+
+	http.HandleFunc("/status", handleStatus)
+	http.HandleFunc("/", handle)
+
+	log.Printf("serving charts from %s on %s", dir, host)
+	log.Fatal(http.ListenAndServe(host, nil))
+}