@@ -3,10 +3,13 @@ package icinga2
33import (
44 "context"
55 "errors"
6+ "fmt"
67 "github.com/google/uuid"
8+ lru "github.com/hashicorp/golang-lru/v2"
79 "github.com/icinga/icinga-notifications/internal/event"
810 "go.uber.org/zap"
911 "golang.org/x/sync/errgroup"
12+ "math"
1013 "net/http"
1114 "net/url"
1215 "time"
@@ -64,6 +67,14 @@ type Client struct {
6467 eventDispatcherEventStream chan * eventMsg
6568 // catchupPhaseRequest requests the main worker to switch to the catch-up-phase to query the API for missed events.
6669 catchupPhaseRequest chan struct {}
70+
71+ // eventExtraTags is used to cache Checkable groups once they have been fetched from the Icinga 2 API so that they
72+ // don't have to be fetched over again with each ongoing event. Host/Service groups are never supposed to change at
73+ // runtime, so this cache is being refreshed once in a while when Icinga 2 dispatches an object created/deleted
74+ // event and thus should not overload the Icinga 2 API in a large environment with numerous Checkables.
75+ // The LRU cache size is defined as 2^17, and when the actual cached items reach this size, the oldest values
76+ // will simply be overwritten by the new ones.
77+ eventExtraTagsCache * lru.Cache [string , map [string ]string ]
6778}
6879
6980// buildCommonEvent creates an event.Event based on Host and (optional) Service attributes to be specified later.
@@ -78,10 +89,9 @@ type Client struct {
7889// - ID
7990func (client * Client ) buildCommonEvent (ctx context.Context , host , service string ) (* event.Event , error ) {
8091 var (
81- eventName string
82- eventUrl * url.URL
83- eventTags map [string ]string
84- eventExtraTags = make (map [string ]string )
92+ eventName string
93+ eventUrl * url.URL
94+ eventTags map [string ]string
8595 )
8696
8797 eventUrl , err := url .Parse (client .IcingaWebRoot )
@@ -99,14 +109,6 @@ func (client *Client) buildCommonEvent(ctx context.Context, host, service string
99109 "host" : host ,
100110 "service" : service ,
101111 }
102-
103- serviceGroups , err := client .fetchHostServiceGroups (ctx , host , service )
104- if err != nil {
105- return nil , err
106- }
107- for _ , serviceGroup := range serviceGroups {
108- eventExtraTags ["servicegroup/" + serviceGroup ] = ""
109- }
110112 } else {
111113 eventName = host
112114
@@ -118,12 +120,27 @@ func (client *Client) buildCommonEvent(ctx context.Context, host, service string
118120 }
119121 }
120122
121- hostGroups , err := client .fetchHostServiceGroups (ctx , host , "" )
122- if err != nil {
123- return nil , err
124- }
125- for _ , hostGroup := range hostGroups {
126- eventExtraTags ["hostgroup/" + hostGroup ] = ""
123+ extraTags := make (map [string ]string )
124+ if existingExtraTags , ok := client .eventExtraTagsCache .Get (eventName ); ok {
125+ extraTags = existingExtraTags
126+ } else {
127+ objectType := "Host"
128+ if service != "" {
129+ objectType = "Service"
130+ }
131+
132+ checkableResult := & CheckableCreatedDeleted {
133+ ObjectName : eventName ,
134+ ObjectType : objectType ,
135+ EventType : typeObjectCreated ,
136+ }
137+
138+ if err := client .refreshExtraTagsCache (ctx , checkableResult ); err != nil {
139+ return nil , err
140+ }
141+ if existingExtraTags , ok := client .eventExtraTagsCache .Get (eventName ); ok {
142+ extraTags = existingExtraTags
143+ }
127144 }
128145
129146 return & event.Event {
@@ -132,10 +149,44 @@ func (client *Client) buildCommonEvent(ctx context.Context, host, service string
132149 Name : eventName ,
133150 URL : eventUrl .String (),
134151 Tags : eventTags ,
135- ExtraTags : eventExtraTags ,
152+ ExtraTags : extraTags ,
136153 }, nil
137154}
138155
156+ // refreshExtraTagsCache refreshes the client event extra tags cache store based on the given response result.
157+ func (client * Client ) refreshExtraTagsCache (ctx context.Context , result * CheckableCreatedDeleted ) error {
158+ switch result .EventType {
159+ case typeObjectDeleted :
160+ // The checkable has just been deleted, so delete all existing extra tags from our cache store as well.
161+ client .eventExtraTagsCache .Remove (result .ObjectName )
162+ case typeObjectCreated :
163+ extraTags := make (map [string ]string )
164+ hostGroups , err := client .fetchHostServiceGroups (ctx , result .GetHostName (), "" )
165+ if err != nil {
166+ return err
167+ }
168+ for _ , hostGroup := range hostGroups {
169+ extraTags ["hostgroup/" + hostGroup ] = ""
170+ }
171+
172+ if result .ObjectType == "Service" {
173+ serviceGroups , err := client .fetchHostServiceGroups (ctx , result .GetHostName (), result .GetServiceName ())
174+ if err != nil {
175+ return err
176+ }
177+ for _ , serviceGroup := range serviceGroups {
178+ extraTags ["servicegroup/" + serviceGroup ] = ""
179+ }
180+ }
181+
182+ client .eventExtraTagsCache .Add (result .ObjectName , extraTags )
183+ default :
184+ return fmt .Errorf ("cannot refresh object extra tags for event-stream type %s" , result .EventType )
185+ }
186+
187+ return nil
188+ }
189+
139190// buildHostServiceEvent constructs an event.Event based on a CheckResult, a Host or Service state, a Host name and an
140191// optional Service name if the Event should represent a Service object.
141192func (client * Client ) buildHostServiceEvent (ctx context.Context , result CheckResult , state int , host , service string ) (* event.Event , error ) {
@@ -441,6 +492,14 @@ func (client *Client) Process() {
441492 client .eventDispatcherEventStream = make (chan * eventMsg )
442493 client .catchupPhaseRequest = make (chan struct {})
443494
495+ cache , err := lru.New [string , map [string ]string ](int (math .Exp2 (17 )))
496+ if err != nil {
497+ // Is unlikely to happen, as the only error being returned is triggered by
498+ // specifying negative numbers as the cache size.
499+ client .Logger .Fatalw ("Failed to initialise event extra tags cache" , zap .Error (err ))
500+ }
501+ client .eventExtraTagsCache = cache
502+
444503 go client .worker ()
445504
446505 for client .Ctx .Err () == nil {
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