MM-24037 Adding getKnowUsers API endpoint (#14332)

* Adding getKnowUsers API endpoint

* Adding i18n strings

* Fixing golint errors

* Adding doc strings

* Remove debug line

* Updating app_iface

* Fixing gofmt

app/app_iface.go

@@ -156,6 +156,10 @@ type AppIface interface {
 	GetEnvironmentConfig() map[string]interface{}
 	// GetHubForUserId returns the hub for a given user id.
 	GetHubForUserId(userId string) *Hub
+	// GetKnownUsers returns the list of user ids of users with any direct
+	// relationship with a user. That means any user sharing any channel, including
+	// direct and group channels.
+	GetKnownUsers(userID string) ([]string, *model.AppError)
 	// GetLdapGroup retrieves a single LDAP group by the given LDAP group id.
 	GetLdapGroup(ldapGroupID string) (*model.Group, *model.AppError)
 	// GetMarketplacePlugins returns a list of plugins from the marketplace-server,

app/opentracing_layer.go

@@ -5702,6 +5702,28 @@ func (a *OpenTracingAppLayer) GetJobsPage(page int, perPage int) ([]*model.Job,
 	return resultVar0, resultVar1
 }
 
+func (a *OpenTracingAppLayer) GetKnownUsers(userID string) ([]string, *model.AppError) {
+	origCtx := a.ctx
+	span, newCtx := tracing.StartSpanWithParentByContext(a.ctx, "app.GetKnownUsers")
+
+	a.ctx = newCtx
+	a.app.Srv().Store.SetContext(newCtx)
+	defer func() {
+		a.app.Srv().Store.SetContext(origCtx)
+		a.ctx = origCtx
+	}()
+
+	defer span.Finish()
+	resultVar0, resultVar1 := a.app.GetKnownUsers(userID)
+
+	if resultVar1 != nil {
+		span.LogFields(spanlog.Error(resultVar1))
+		ext.Error.Set(span, true)
+	}
+
+	return resultVar0, resultVar1
+}
+
 func (a *OpenTracingAppLayer) GetLatestTermsOfService() (*model.TermsOfService, *model.AppError) {
 	origCtx := a.ctx
 	span, newCtx := tracing.StartSpanWithParentByContext(a.ctx, "app.GetLatestTermsOfService")

app/user.go

@@ -2083,3 +2083,10 @@ func (a *App) invalidateUserCacheAndPublish(userId string) {
 	message.Add("user", user)
 	a.Publish(message)
 }
+
+// GetKnownUsers returns the list of user ids of users with any direct
+// relationship with a user. That means any user sharing any channel, including
+// direct and group channels.
+func (a *App) GetKnownUsers(userID string) ([]string, *model.AppError) {
+	return a.Srv().Store.User().GetKnownUsers(userID)
+}