MM-8607 Add ability to turn off non-critical services when under load (#13212)

* MM-8607: add ability to turn off non-critical services under load

* server busy invalid param unit tests

* MM-8607: rename server busy endpoints

* MM-8607: handle case where App not initialized

* MM-8607: additional unit test cases per feedback.

* MM-8607: use decorator to check isbusy when adding endpoint route

* MM-8607: rename endpoints, use struct for json

* Update api4/system.go

Fix misspelled log output

Co-Authored-By: Saturnino Abril <saturnino.abril@gmail.com>

* MM-8607: fix i18n order; max seconds for server busy expiry

model/client4.go

@@ -420,6 +420,10 @@ func (c *Client4) GetRedirectLocationRoute() string {
 	return fmt.Sprintf("/redirect_location")
 }
 
+func (c *Client4) GetServerBusyRoute() string {
+	return "/server_busy"
+}
+
 func (c *Client4) GetUserTermsOfServiceRoute(userId string) string {
 	return c.GetUserRoute(userId) + "/terms_of_service"
 }
@@ -4622,6 +4626,41 @@ func (c *Client4) GetRedirectLocation(urlParam, etag string) (string, *Response)
 	return MapFromJson(r.Body)["location"], BuildResponse(r)
 }
 
+// SetServerBusy will mark the server as busy, which disables non-critical services for `secs` seconds.
+func (c *Client4) SetServerBusy(secs int) (bool, *Response) {
+	url := fmt.Sprintf("%s?seconds=%d", c.GetServerBusyRoute(), secs)
+	r, err := c.DoApiPost(url, "")
+	if err != nil {
+		return false, BuildErrorResponse(r, err)
+	}
+	defer closeBody(r)
+	return CheckStatusOK(r), BuildResponse(r)
+}
+
+// ClearServerBusy will mark the server as not busy.
+func (c *Client4) ClearServerBusy() (bool, *Response) {
+	r, err := c.DoApiPost(c.GetServerBusyRoute()+"/clear", "")
+	if err != nil {
+		return false, BuildErrorResponse(r, err)
+	}
+	defer closeBody(r)
+	return CheckStatusOK(r), BuildResponse(r)
+}
+
+// GetServerBusyExpires returns the time when a server marked busy
+// will automatically have the flag cleared.
+func (c *Client4) GetServerBusyExpires() (*time.Time, *Response) {
+	r, err := c.DoApiGet(c.GetServerBusyRoute(), "")
+	if err != nil {
+		return nil, BuildErrorResponse(r, err)
+	}
+	defer closeBody(r)
+
+	sbs := ServerBusyStateFromJson(r.Body)
+	expires := time.Unix(sbs.Expires, 0)
+	return &expires, BuildResponse(r)
+}
+
 // RegisterTermsOfServiceAction saves action performed by a user against a specific terms of service.
 func (c *Client4) RegisterTermsOfServiceAction(userId, termsOfServiceId string, accepted bool) (*bool, *Response) {
 	url := c.GetUserTermsOfServiceRoute(userId)

model/system.go

@@ -50,3 +50,20 @@ type SystemECDSAKey struct {
 	Y     *big.Int `json:"y"`
 	D     *big.Int `json:"d,omitempty"`
 }
+
+type ServerBusyState struct {
+	Busy       bool   `json:"busy"`
+	Expires    int64  `json:"expires"`
+	Expires_ts string `json:"expires_ts,omitempty"`
+}
+
+func (sbs *ServerBusyState) ToJson() string {
+	b, _ := json.Marshal(sbs)
+	return string(b)
+}
+
+func ServerBusyStateFromJson(r io.Reader) *ServerBusyState {
+	var sbs *ServerBusyState
+	json.NewDecoder(r).Decode(&sbs)
+	return sbs
+}

model/system_test.go

@@ -6,6 +6,7 @@ package model
 import (
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/require"
 )
@@ -17,3 +18,13 @@ func TestSystemJson(t *testing.T) {
 
 	require.Equal(t, "test", result.Name, "ids do not match")
 }
+
+func TestServerBusyJson(t *testing.T) {
+	now := time.Now()
+	sbs := ServerBusyState{Busy: true, Expires: now.Unix()}
+	json := sbs.ToJson()
+	result := ServerBusyStateFromJson(strings.NewReader(json))
+
+	require.Equal(t, sbs.Busy, result.Busy, "busy state does not match")
+	require.Equal(t, sbs.Expires, result.Expires, "expiry does not match")
+}

model/utils.go

@@ -207,7 +207,7 @@ func MapToJson(objmap map[string]string) string {
 	return string(b)
 }
 
-// MapToJson converts a map to a json string
+// MapBoolToJson converts a map to a json string
 func MapBoolToJson(objmap map[string]bool) string {
 	b, _ := json.Marshal(objmap)
 	return string(b)