cloudflare/pint
Publicmirrored from https://github.com/cloudflare/pintAvailable
internal/promapi/failover.go
196lines · modecode
| 1 | package promapi |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "regexp" |
| 6 | "time" |
| 7 | |
| 8 | "github.com/prometheus/client_golang/prometheus" |
| 9 | ) |
| 10 | |
| 11 | type FailoverGroupError struct { |
| 12 | err error |
| 13 | uri string |
| 14 | isStrict bool |
| 15 | } |
| 16 | |
| 17 | func (e *FailoverGroupError) Unwrap() error { |
| 18 | return e.err |
| 19 | } |
| 20 | |
| 21 | func (e *FailoverGroupError) Error() string { |
| 22 | return e.err.Error() |
| 23 | } |
| 24 | |
| 25 | func (e *FailoverGroupError) URI() string { |
| 26 | return e.uri |
| 27 | } |
| 28 | |
| 29 | func (e *FailoverGroupError) IsStrict() bool { |
| 30 | return e.isStrict |
| 31 | } |
| 32 | |
| 33 | func cacheCleaner(cache *queryCache, interval time.Duration, quit chan bool) { |
| 34 | ticker := time.NewTicker(interval) |
| 35 | for { |
| 36 | select { |
| 37 | case <-quit: |
| 38 | return |
| 39 | case <-ticker.C: |
| 40 | cache.gc() |
| 41 | } |
| 42 | } |
| 43 | } |
| 44 | |
| 45 | type FailoverGroup struct { |
| 46 | name string |
| 47 | servers []*Prometheus |
| 48 | strictErrors bool |
| 49 | uptimeMetric string |
| 50 | cacheCollector *cacheCollector |
| 51 | quitChan chan bool |
| 52 | |
| 53 | pathsInclude []*regexp.Regexp |
| 54 | pathsExclude []*regexp.Regexp |
| 55 | } |
| 56 | |
| 57 | func NewFailoverGroup(name string, servers []*Prometheus, strictErrors bool, uptimeMetric string, include, exclude []*regexp.Regexp) *FailoverGroup { |
| 58 | return &FailoverGroup{ |
| 59 | name: name, |
| 60 | servers: servers, |
| 61 | strictErrors: strictErrors, |
| 62 | uptimeMetric: uptimeMetric, |
| 63 | pathsInclude: include, |
| 64 | pathsExclude: exclude, |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | func (fg *FailoverGroup) Name() string { |
| 69 | return fg.name |
| 70 | } |
| 71 | |
| 72 | func (fg *FailoverGroup) UptimeMetric() string { |
| 73 | return fg.uptimeMetric |
| 74 | } |
| 75 | |
| 76 | func (fg *FailoverGroup) IsEnabledForPath(path string) bool { |
| 77 | if len(fg.pathsInclude) == 0 && len(fg.pathsExclude) == 0 { |
| 78 | return true |
| 79 | } |
| 80 | for _, re := range fg.pathsExclude { |
| 81 | if re.MatchString(path) { |
| 82 | return false |
| 83 | } |
| 84 | } |
| 85 | for _, re := range fg.pathsInclude { |
| 86 | if re.MatchString(path) { |
| 87 | return true |
| 88 | } |
| 89 | } |
| 90 | return false |
| 91 | } |
| 92 | |
| 93 | func (fg *FailoverGroup) StartWorkers() { |
| 94 | queryCache := newQueryCache(time.Hour) |
| 95 | fg.quitChan = make(chan bool) |
| 96 | go cacheCleaner(queryCache, time.Minute*2, fg.quitChan) |
| 97 | |
| 98 | fg.cacheCollector = newCacheCollector(queryCache, fg.name) |
| 99 | prometheus.MustRegister(fg.cacheCollector) |
| 100 | for _, prom := range fg.servers { |
| 101 | prom.cache = queryCache |
| 102 | prom.StartWorkers() |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | func (fg *FailoverGroup) Close() { |
| 107 | for _, prom := range fg.servers { |
| 108 | prom.Close() |
| 109 | } |
| 110 | prometheus.Unregister(fg.cacheCollector) |
| 111 | fg.quitChan <- true |
| 112 | } |
| 113 | |
| 114 | func (fg *FailoverGroup) CleanCache() { |
| 115 | for _, prom := range fg.servers { |
| 116 | if prom.cache != nil { |
| 117 | prom.cache.gc() |
| 118 | return |
| 119 | } |
| 120 | } |
| 121 | } |
| 122 | |
| 123 | func (fg *FailoverGroup) Config(ctx context.Context) (cfg *ConfigResult, err error) { |
| 124 | var uri string |
| 125 | for _, prom := range fg.servers { |
| 126 | uri = prom.safeURI |
| 127 | cfg, err = prom.Config(ctx) |
| 128 | if err == nil { |
| 129 | return |
| 130 | } |
| 131 | if !IsUnavailableError(err) { |
| 132 | return nil, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 133 | } |
| 134 | } |
| 135 | return nil, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 136 | } |
| 137 | |
| 138 | func (fg *FailoverGroup) Query(ctx context.Context, expr string) (qr *QueryResult, err error) { |
| 139 | var uri string |
| 140 | for _, prom := range fg.servers { |
| 141 | uri = prom.safeURI |
| 142 | qr, err = prom.Query(ctx, expr) |
| 143 | if err == nil { |
| 144 | return |
| 145 | } |
| 146 | if !IsUnavailableError(err) { |
| 147 | return qr, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 148 | } |
| 149 | } |
| 150 | return nil, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 151 | } |
| 152 | |
| 153 | func (fg *FailoverGroup) RangeQuery(ctx context.Context, expr string, params RangeQueryTimes) (rqr *RangeQueryResult, err error) { |
| 154 | var uri string |
| 155 | for _, prom := range fg.servers { |
| 156 | uri = prom.safeURI |
| 157 | rqr, err = prom.RangeQuery(ctx, expr, params) |
| 158 | if err == nil { |
| 159 | return |
| 160 | } |
| 161 | if !IsUnavailableError(err) { |
| 162 | return rqr, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 163 | } |
| 164 | } |
| 165 | return nil, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 166 | } |
| 167 | |
| 168 | func (fg *FailoverGroup) Metadata(ctx context.Context, metric string) (metadata *MetadataResult, err error) { |
| 169 | var uri string |
| 170 | for _, prom := range fg.servers { |
| 171 | uri = prom.safeURI |
| 172 | metadata, err = prom.Metadata(ctx, metric) |
| 173 | if err == nil { |
| 174 | return |
| 175 | } |
| 176 | if !IsUnavailableError(err) { |
| 177 | return metadata, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 178 | } |
| 179 | } |
| 180 | return nil, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 181 | } |
| 182 | |
| 183 | func (fg *FailoverGroup) Flags(ctx context.Context) (flags *FlagsResult, err error) { |
| 184 | var uri string |
| 185 | for _, prom := range fg.servers { |
| 186 | uri = prom.safeURI |
| 187 | flags, err = prom.Flags(ctx) |
| 188 | if err == nil { |
| 189 | return |
| 190 | } |
| 191 | if !IsUnavailableError(err) { |
| 192 | return nil, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 193 | } |
| 194 | } |
| 195 | return nil, &FailoverGroupError{err: err, uri: uri, isStrict: fg.strictErrors} |
| 196 | } |
| 197 | |