From 55d927d1ae7704f2b3ab9598cd1bb71620a1a24a Mon Sep 17 00:00:00 2001
From: cskh <hui.kang@hashicorp.com>
Date: Thu, 15 Jun 2023 23:53:02 -0400
Subject: [PATCH] tag support for -type=checks -service=foo

---
 agent/health_endpoint.go |  12 +++++
 api/health.go            |  10 ++++
 api/watch/funcs.go       |   2 +-
 api/watch/funcs_test.go  | 106 ++++++++++++++++++++++++++++++++++++++-
 4 files changed, 128 insertions(+), 2 deletions(-)

diff --git a/agent/health_endpoint.go b/agent/health_endpoint.go
index 9663ed5769ee..2ba9bea4dbb4 100644
--- a/agent/health_endpoint.go
+++ b/agent/health_endpoint.go
@@ -140,6 +140,18 @@ func (s *HTTPHandlers) HealthServiceChecks(resp http.ResponseWriter, req *http.R
 		return nil, HTTPError{StatusCode: http.StatusBadRequest, Reason: "Missing service name"}
 	}
 
+	// build tag filter
+	params := req.URL.Query()
+	if tags, ok := params["tag"]; ok {
+		for i, tag := range tags {
+			expr := fmt.Sprintf(`%s in ServiceTags`, tag)
+			if i < len(tags)-1 {
+				expr += " and "
+			}
+			args.Filter += expr
+		}
+	}
+
 	// Make the RPC request
 	var out structs.IndexedHealthChecks
 	defer setMeta(resp, &out.QueryMeta)
diff --git a/api/health.go b/api/health.go
index 76619bbe1901..480f492f494b 100644
--- a/api/health.go
+++ b/api/health.go
@@ -261,7 +261,17 @@ func (h *Health) Node(node string, q *QueryOptions) (HealthChecks, *QueryMeta, e
 
 // Checks is used to return the checks associated with a service
 func (h *Health) Checks(service string, q *QueryOptions) (HealthChecks, *QueryMeta, error) {
+	return h.ChecksTags(service, nil, q)
+}
+
+// ChecksTags is used to return the checks associated with a service filtered by tags
+func (h *Health) ChecksTags(service string, tags []string, q *QueryOptions) (HealthChecks, *QueryMeta, error) {
 	r := h.c.newRequest("GET", "/v1/health/checks/"+service)
+	if len(tags) > 0 {
+		for _, tag := range tags {
+			r.params.Add("tag", tag)
+		}
+	}
 	r.setQueryOptions(q)
 	rtt, resp, err := h.c.doRequest(r)
 	if err != nil {
diff --git a/api/watch/funcs.go b/api/watch/funcs.go
index 5cf15b562ec1..33e3223d5f55 100644
--- a/api/watch/funcs.go
+++ b/api/watch/funcs.go
@@ -206,7 +206,7 @@ func checksWatch(params map[string]interface{}) (WatcherFunc, error) {
 		if state != "" {
 			checks, meta, err = health.StateTags(state, tags, &opts)
 		} else {
-			checks, meta, err = health.Checks(service, &opts)
+			checks, meta, err = health.ChecksTags(service, tags, &opts)
 		}
 		if err != nil {
 			return nil, nil, err
diff --git a/api/watch/funcs_test.go b/api/watch/funcs_test.go
index 25e20c8d0721..d3562397c79b 100644
--- a/api/watch/funcs_test.go
+++ b/api/watch/funcs_test.go
@@ -772,7 +772,111 @@ func TestChecksWatch_Service(t *testing.T) {
 	}
 }
 
-func TestChecksWatch_Service_Tags(t *testing.T) {
+func TestChecksWatch_Service_Tag(t *testing.T) {
+	t.Parallel()
+	c, s := makeClient(t)
+	defer s.Stop()
+
+	s.WaitForSerfCheck(t)
+
+	var (
+		wakeups  [][]*api.HealthCheck
+		notifyCh = make(chan struct{})
+	)
+
+	plan := mustParse(t, `{"type":"checks", "service":"foobar", "tag":["b", "a"]}`)
+	plan.Handler = func(idx uint64, raw interface{}) {
+		if raw == nil {
+			return // ignore
+		}
+		v, ok := raw.([]*api.HealthCheck)
+		if !ok {
+			return // ignore
+		}
+		wakeups = append(wakeups, v)
+		notifyCh <- struct{}{}
+	}
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		if err := plan.Run(s.HTTPAddr); err != nil {
+			t.Errorf("err: %v", err)
+		}
+	}()
+	defer plan.Stop()
+
+	// Wait for first wakeup.
+	<-notifyCh
+	{
+		catalog := c.Catalog()
+
+		// we want to find this one
+		reg := &api.CatalogRegistration{
+			Node:       "foobar",
+			Address:    "1.1.1.1",
+			Datacenter: "dc1",
+			Service: &api.AgentService{
+				ID:      "foobar",
+				Service: "foobar",
+				Tags:    []string{"a", "b"},
+			},
+			Check: &api.AgentCheck{
+				Node:      "foobar",
+				CheckID:   "foobar",
+				Name:      "foobar",
+				Status:    api.HealthPassing,
+				ServiceID: "foobar",
+			},
+		}
+		if _, err := catalog.Register(reg, nil); err != nil {
+			t.Fatalf("err: %v", err)
+		}
+
+		// we don't want to find this one
+		reg = &api.CatalogRegistration{
+			Node:       "bar",
+			Address:    "2.2.2.2",
+			Datacenter: "dc1",
+			Service: &api.AgentService{
+				ID:      "foobar",
+				Service: "foobar",
+				Tags:    []string{"a"},
+			},
+			Check: &api.AgentCheck{
+				Node:      "bar",
+				CheckID:   "foobar",
+				Name:      "foobar",
+				Status:    api.HealthPassing,
+				ServiceID: "foobar",
+			},
+		}
+		if _, err := catalog.Register(reg, nil); err != nil {
+			t.Fatalf("err: %v", err)
+		}
+	}
+
+	// Wait for second wakeup.
+	<-notifyCh
+
+	plan.Stop()
+	wg.Wait()
+
+	require.Len(t, wakeups, 2)
+
+	{
+		v := wakeups[0]
+		require.Len(t, v, 0)
+	}
+	{
+		v := wakeups[1]
+		require.Len(t, v, 1)
+		require.Equal(t, "foobar", v[0].CheckID)
+	}
+}
+
+func TestChecksWatch_Tag(t *testing.T) {
 	t.Parallel()
 	c, s := makeClient(t)
 	defer s.Stop()