From 45e091bca5ceead863589be607710a9aec206a70 Mon Sep 17 00:00:00 2001
From: Chanwit Kaewkasi <chanwit@gmail.com>
Date: Tue, 25 Aug 2015 21:19:29 +0700
Subject: [PATCH] implement grouping list of images by Id

Signed-off-by: Chanwit Kaewkasi <chanwit@gmail.com>
---
 api/handlers.go                  | 29 ++++++++++++++++++++++++++---
 test/integration/api/images.bats | 10 +++++-----
 test/integration/api/pull.bats   |  6 +++---
 test/integration/api/tag.bats    |  8 ++++++--
 4 files changed, 40 insertions(+), 13 deletions(-)

diff --git a/api/handlers.go b/api/handlers.go
index 7fc93b9c42..56891ddc18 100644
--- a/api/handlers.go
+++ b/api/handlers.go
@@ -123,8 +123,9 @@ func getImagesJSON(c *context, w http.ResponseWriter, r *http.Request) {
 	}
 
 	accepteds, _ := filters["node"]
-	images := []*cluster.Image{}
-
+	// this struct helps grouping images
+	// but still keeps their Engine infos as an array.
+	groupImages := make(map[string]dockerclient.Image)
 	for _, image := range c.cluster.Images(all) {
 		if len(accepteds) != 0 {
 			found := false
@@ -138,9 +139,31 @@ func getImagesJSON(c *context, w http.ResponseWriter, r *http.Request) {
 				continue
 			}
 		}
-		images = append(images, image)
+
+		// grouping images by Id, and concat their RepoTags
+		if entry, existed := groupImages[image.Id]; existed {
+			entry.RepoTags = append(entry.RepoTags, image.RepoTags...)
+			groupImages[image.Id] = entry
+		} else {
+			groupImages[image.Id] = image.Image
+		}
 	}
 
+	images := []dockerclient.Image{}
+
+	for _, image := range groupImages {
+		// de-duplicate RepoTags
+		result := []string{}
+		seen := map[string]bool{}
+		for _, val := range image.RepoTags {
+			if _, ok := seen[val]; !ok {
+				result = append(result, val)
+				seen[val] = true
+			}
+		}
+		image.RepoTags = result
+		images = append(images, image)
+	}
 	w.Header().Set("Content-Type", "application/json")
 	json.NewEncoder(w).Encode(images)
 }
diff --git a/test/integration/api/images.bats b/test/integration/api/images.bats
index 6154bc6b7b..03402e1c8b 100644
--- a/test/integration/api/images.bats
+++ b/test/integration/api/images.bats
@@ -14,16 +14,15 @@ function teardown() {
 	start_docker_with_busybox 2
 	swarm_manage
 
-
-	# we should get 2 busyboxes, plus the header.
+	# With grouping, we should get 1 busybox, plus the header.
 	run docker_swarm images
 	[ "$status" -eq 0 ]
-	[ "${#lines[@]}" -eq 3 ]
+	[ "${#lines[@]}" -eq 2 ]
 	# Every line should contain "busybox" except for the header
 	for((i=1; i<${#lines[@]}; i++)); do
 		[[ "${lines[i]}" == *"busybox"* ]]
 	done
-	
+
 	# Try with --filter.
 	run docker_swarm images --filter node=node-0
 	[ "$status" -eq 0 ]
@@ -40,6 +39,7 @@ function teardown() {
 	[[ "${lines[1]}" == *"busybox"* ]]
 
 	# Try images -a
+	# lines are: header, busybox, <none>, <none>
 	run docker_swarm images -a
-	[ "${#lines[@]}" -ge 5 ]
+	[ "${#lines[@]}" -ge 4 ]
 }
diff --git a/test/integration/api/pull.bats b/test/integration/api/pull.bats
index 32c600c112..1e27c4549a 100644
--- a/test/integration/api/pull.bats
+++ b/test/integration/api/pull.bats
@@ -18,11 +18,11 @@ function teardown() {
 
 	docker_swarm pull busybox
 
-	# we should get 2 busyboxes, plus the header.
+	# with grouping, we should get 1 busybox, plus the header.
 	run docker_swarm images
 	[ "$status" -eq 0 ]
-	[ "${#lines[@]}" -eq 3 ]
-	# every line should contain "busybox" exclude the first head line 
+	[ "${#lines[@]}" -eq 2 ]
+	# every line should contain "busybox" exclude the first head line
 	for((i=1; i<${#lines[@]}; i++)); do
 		[[ "${lines[i]}" == *"busybox"* ]]
 	done
diff --git a/test/integration/api/tag.bats b/test/integration/api/tag.bats
index d03c0dd65e..ff340cc4dc 100644
--- a/test/integration/api/tag.bats
+++ b/test/integration/api/tag.bats
@@ -46,6 +46,10 @@ function teardown() {
 	docker_swarm tag busybox tag_busybox:test
 
 	# verify
-	run docker_swarm images
-	[[ $(echo ${output} | grep -o "tag_busybox" | wc -l) == 2 ]]
+	# change the way to verify tagged image on each node after image deduplication
+	run docker_swarm images --filter node=node-0
+	[[ $(echo ${output} | grep -o "tag_busybox" | wc -l) == 1 ]]
+
+	run docker_swarm images --filter node=node-1
+	[[ $(echo ${output} | grep -o "tag_busybox" | wc -l) == 1 ]]
 }