feat: Implement /check/query endpoint as QueryCheck (#388)

* feat: Implement /check/query endpoint as QueryCheck

Adds a new method `QueryCheck` that is a wrapper for the
[/check/query](https://synthetic-monitoring-api-dev.grafana-dev.net/api/v1/swagger#/operations/GET_/api/v1/check/query)
api end point. It accepts a job and a target which gets added as query
parameters to the url. QueryCheck returns a single check that gets
matched.

Implements a basic set of tests that emulates the api end filtering
checks by job and target. Ensures that it handles the case where no
checks are matched.

* Update QueryCheck to handle missing job/target

Return an error from `QueryCheck` if job or target are empty strings.
Refactor the unit tests to handle 404 errors and validate that job and
target cannot be set.

* Update Query method documentation

* Fix linting errors

Author: Pokom

smapi.go

@@ -505,6 +505,30 @@ func (h *Client) ListChecks(ctx context.Context) ([]synthetic_monitoring.Check,
 	return result, nil
 }
 
+// QueryCheck returns a Synthetic Monitoring check for the
+// authenticated tenant that matches the job and target passed in.
+// Job and Target must be set to non empty strings.
+func (h *Client) QueryCheck(ctx context.Context, job string, target string) (*synthetic_monitoring.Check, error) {
+	if job == "" || target == "" {
+		return nil, fmt.Errorf("check query request: target and job must be set")
+	}
+	if err := h.requireAuthToken(); err != nil {
+		return nil, err
+	}
+
+	resp, err := h.Get(ctx, fmt.Sprintf("/check/query?job=%s&target=%s", job, target), true, nil)
+	if err != nil {
+		return nil, fmt.Errorf("check query err: %w", err)
+	}
+
+	var result *synthetic_monitoring.Check
+
+	if err := ValidateResponse("check query request", resp, &result); err != nil {
+		return nil, err
+	}
+	return result, nil
+}
+
 // GetTenant retrieves the information associated with the authenticated
 // tenant.
 func (h *Client) GetTenant(ctx context.Context) (*synthetic_monitoring.Tenant, error) {

smapi_test.go

@@ -1294,6 +1294,79 @@ func TestListChecks(t *testing.T) {
 	require.ElementsMatch(t, checks, actualChecks)
 }
 
+func TestQueryChecks(t *testing.T) {
+	orgs := orgs()
+	testTenant := orgs.findTenantByOrg(1000)
+	testTenantId := testTenant.id
+	checks := []synthetic_monitoring.Check{
+		{
+			Id:       42,
+			TenantId: testTenantId,
+			Job:      "testing",
+			Target:   "icanhazip.com",
+		},
+		{
+			Id:       84,
+			TenantId: testTenantId,
+			Job:      "not-testing",
+			Target:   "nocanhazip.com",
+		},
+	}
+	url, mux, cleanup := newTestServer(t)
+	defer cleanup()
+	mux.Handle("/api/v1/check/query", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var resp *synthetic_monitoring.Check
+		fmt.Println(r.URL.RawQuery)
+		job := r.URL.Query().Get("job")
+		target := r.URL.Query().Get("target")
+		// Emulate searching for a check
+		for _, check := range checks {
+			if check.Job == job && check.Target == target {
+				resp = &check
+				break
+			}
+		}
+		if resp != nil {
+			writeResponse(w, http.StatusOK, &resp)
+			return
+		}
+		errorResponse(w, http.StatusNotFound, fmt.Sprintf("check with target %s and job %s", target, job))
+	}))
+
+	c := NewClient(url, testTenant.token, http.DefaultClient)
+	t.Run("Validate checks can be found", func(t *testing.T) {
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		filteredChecks, err := c.QueryCheck(ctx, "testing", "icanhazip.com")
+		require.NoError(t, err)
+		require.NotNil(t, filteredChecks)
+		require.Equal(t, filteredChecks.Target, "icanhazip.com")
+	})
+	t.Run("Validate another check can be found", func(t *testing.T) {
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		filteredChecks, err := c.QueryCheck(ctx, "not-testing", "nocanhazip.com")
+		require.NoError(t, err)
+		require.NotNil(t, filteredChecks)
+		require.Equal(t, filteredChecks.Target, "nocanhazip.com")
+	})
+	t.Run("Validate a not found check returns a 404", func(t *testing.T) {
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		filteredChecks, err := c.QueryCheck(ctx, "not-found", "nocanhazip.com")
+		require.Error(t, err)
+		require.Nil(t, filteredChecks)
+	})
+
+	t.Run("Ensure the client checks for missing jobs and checks", func(t *testing.T) {
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		filteredChecks, err := c.QueryCheck(ctx, "", "")
+		require.EqualError(t, err, "check query request: target and job must be set")
+		require.Nil(t, filteredChecks)
+	})
+}
+
 func TestGetTenant(t *testing.T) {
 	orgs := orgs()