From c7b155c06452315396ec98f42cf5b502be38b221 Mon Sep 17 00:00:00 2001
From: Tim Pierce <twp@curoverse.com>
Date: Wed, 9 Apr 2014 18:03:19 -0400
Subject: [PATCH] Added /index handlers. (refs #2561)

---
 services/keep/keep.go      | 63 ++++++++++++++++++++++++++++++++++++--
 services/keep/keep_test.go | 36 ++++++++++++++++++++++
 2 files changed, 97 insertions(+), 2 deletions(-)

diff --git a/services/keep/keep.go b/services/keep/keep.go
index 5083e690a1..adffaa477c 100644
--- a/services/keep/keep.go
+++ b/services/keep/keep.go
@@ -11,6 +11,7 @@ import (
 	"net/http"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strconv"
 	"strings"
 	"time"
@@ -64,8 +65,10 @@ func main() {
 	// appropriate handler.
 	//
 	rest := mux.NewRouter()
-	rest.HandleFunc("/{hash:[0-9a-f]{32}}", GetBlockHandler).Methods("GET")
-	rest.HandleFunc("/{hash:[0-9a-f]{32}}", PutBlockHandler).Methods("PUT")
+	rest.HandleFunc(`/{hash:[0-9a-f]{32}}`, GetBlockHandler).Methods("GET", "HEAD")
+	rest.HandleFunc(`/{hash:[0-9a-f]{32}}`, PutBlockHandler).Methods("PUT")
+	rest.HandleFunc(`/index`, IndexHandler).Methods("GET", "HEAD")
+	rest.HandleFunc(`/index/{prefix:[0-9a-f]{0,32}}`, IndexHandler).Methods("GET", "HEAD")
 
 	// Tell the built-in HTTP server to direct all requests to the REST
 	// router.
@@ -144,6 +147,62 @@ func PutBlockHandler(w http.ResponseWriter, req *http.Request) {
 	}
 }
 
+func IndexHandler(w http.ResponseWriter, req *http.Request) {
+	prefix := mux.Vars(req)["prefix"]
+
+	index := IndexLocators(prefix)
+	w.Write([]byte(index))
+}
+
+// IndexLocators
+//     Returns a string containing a list of locator ids found on this
+//     Keep server.  If {prefix} is given, return only those locator
+//     ids that begin with the given prefix string.
+//
+//     The return string consists of a sequence of newline-separated
+//     strings in the format
+//
+//         locator+size modification-time
+//
+//     e.g.:
+//
+//         e4df392f86be161ca6ed3773a962b8f3+67108864 1388894303
+//         e4d41e6fd68460e0e3fc18cc746959d2+67108864 1377796043
+//         e4de7a2810f5554cd39b36d8ddb132ff+67108864 1388701136
+//
+func IndexLocators(prefix string) string {
+	var output string
+	for _, vol := range KeepVolumes {
+		filepath.Walk(vol,
+			func(path string, info os.FileInfo, err error) error {
+				// This WalkFunc inspects each path in the volume
+				// and prints an index line for all files that begin
+				// with prefix.
+				if err != nil {
+					log.Printf("IndexHandler: %s: walking to %s: %s",
+						vol, path, err)
+					return nil
+				}
+				locator := filepath.Base(path)
+				// Skip directories that do not match prefix.
+				// We know there is nothing interesting inside.
+				if info.IsDir() &&
+					!strings.HasPrefix(locator, prefix) &&
+					!strings.HasPrefix(prefix, locator) {
+					return filepath.SkipDir
+				}
+				// Print filenames beginning with prefix
+				if !info.IsDir() && strings.HasPrefix(locator, prefix) {
+					output = output + fmt.Sprintf(
+						"%s+%d %d\n", locator, info.Size(), info.ModTime().Unix())
+				}
+				return nil
+			})
+	}
+
+	return output
+}
+
 func GetBlock(hash string) ([]byte, error) {
 	var buf = make([]byte, BLOCKSIZE)
 
diff --git a/services/keep/keep_test.go b/services/keep/keep_test.go
index cb5e89cfb9..2aa8aff77c 100644
--- a/services/keep/keep_test.go
+++ b/services/keep/keep_test.go
@@ -5,11 +5,21 @@ import (
 	"io/ioutil"
 	"os"
 	"path"
+	"regexp"
 	"testing"
 )
 
 var TEST_BLOCK = []byte("The quick brown fox jumps over the lazy dog.")
 var TEST_HASH = "e4d909c290d0fb1ca068ffaddf22cbd0"
+
+var TEST_BLOCK_2 = []byte("Pack my box with five dozen liquor jugs.")
+var TEST_HASH_2 = "f15ac516f788aec4f30932ffb6395c39"
+
+var TEST_BLOCK_3 = []byte("Now is the time for all good men to come to the aid of their country.")
+var TEST_HASH_3 = "eed29bbffbc2dbe5e5ee0bb71888e61f"
+
+// BAD_BLOCK is used to test collisions and corruption.
+// It must not match any test hashes.
 var BAD_BLOCK = []byte("The magic words are squeamish ossifrage.")
 
 // ========================================
@@ -244,6 +254,32 @@ func TestFindKeepVolumesFail(t *testing.T) {
 	}
 }
 
+// TestIndex
+//     Test an /index request.
+func TestIndex(t *testing.T) {
+	defer teardown()
+
+	// Set up Keep volumes and populate them.
+	KeepVolumes = setup(t, 2)
+	store(t, KeepVolumes[0], TEST_HASH, TEST_BLOCK)
+	store(t, KeepVolumes[1], TEST_HASH_2, TEST_BLOCK_2)
+	store(t, KeepVolumes[0], TEST_HASH_3, TEST_BLOCK_3)
+
+	index := IndexLocators("")
+	expected := `^` + TEST_HASH + `\+\d+ \d+\n` +
+		TEST_HASH_3 + `\+\d+ \d+\n` +
+		TEST_HASH_2 + `\+\d+ \d+\n$`
+
+	match, err := regexp.MatchString(expected, index)
+	if err == nil {
+		if !match {
+			t.Errorf("IndexLocators returned:\n-----\n%s-----\n", index)
+		}
+	} else {
+		t.Errorf("regexp.MatchString: %s", err)
+	}
+}
+
 // ========================================
 // Helper functions for unit tests.
 // ========================================
-- 
2.30.2