Bolt backup endpoint (#514)

cmd/micromdm/serve.go

@@ -10,9 +10,11 @@ import (
 	"net/url"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"time"
 
+	"github.com/boltdb/bolt"
 	"github.com/go-kit/kit/auth/basic"
 	"github.com/go-kit/kit/log"
 	httptransport "github.com/go-kit/kit/transport/http"
@@ -240,6 +242,8 @@ func serve(args []string) error {
 
 		depsyncEndpoints := sync.MakeServerEndpoints(sync.NewService(syncer, sm.SyncDB), basicAuthEndpointMiddleware)
 		sync.RegisterHTTPHandlers(r, depsyncEndpoints, options...)
+
+		r.HandleFunc("/boltbackup", httputil2.RequireBasicAuth(boltBackup(sm.DB), "micromdm", *flAPIKey, "micromdm"))
 	} else {
 		mainLogger.Log("msg", "no api key specified")
 	}
@@ -310,6 +314,21 @@ func serveOptions(
 	return serveOpts
 }
 
+func boltBackup(db *bolt.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		err := db.View(func(tx *bolt.Tx) error {
+			w.Header().Set("Content-Type", "application/octet-stream")
+			w.Header().Set("Content-Disposition", `attachment; filename="micromdm.db"`)
+			w.Header().Set("Content-Length", strconv.Itoa(int(tx.Size())))
+			_, err := tx.WriteTo(w)
+			return err
+		})
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+		}
+	}
+}
+
 func printExamples() {
 	const exampleText = `
 		Quickstart:

pkg/httputil/httputil.go

@@ -2,6 +2,7 @@ package httputil
 
 import (
 	"context"
+	"crypto/subtle"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -124,3 +125,16 @@ func DecodeJSONResponse(r *http.Response, into interface{}) error {
 	err := json.NewDecoder(r.Body).Decode(into)
 	return err
 }
+
+func RequireBasicAuth(h http.HandlerFunc, username, password, realm string) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		u, p, ok := r.BasicAuth()
+		if !ok || subtle.ConstantTimeCompare([]byte(u), []byte(username)) != 1 || subtle.ConstantTimeCompare([]byte(p), []byte(password)) != 1 {
+			w.Header().Set("WWW-Authenticate", `Basic realm="`+realm+`"`)
+			w.WriteHeader(401)
+			w.Write([]byte("Authorization Required\n"))
+			return
+		}
+		h(w, r)
+	}
+}