cloudflare/pint
Publicmirrored from https://github.com/cloudflare/pintAvailable
internal/promapi/config.go
154lines · modecode
| 1 | package promapi |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "fmt" |
| 6 | "io" |
| 7 | "log/slog" |
| 8 | "net/http" |
| 9 | "net/url" |
| 10 | "time" |
| 11 | |
| 12 | "github.com/go-json-experiment/json" |
| 13 | v1 "github.com/prometheus/client_golang/api/prometheus/v1" |
| 14 | "go.yaml.in/yaml/v3" |
| 15 | ) |
| 16 | |
| 17 | const ( |
| 18 | APIPathConfig = "/api/v1/status/config" |
| 19 | ) |
| 20 | |
| 21 | type ConfigSectionGlobal struct { |
| 22 | ExternalLabels map[string]string `yaml:"external_labels"` |
| 23 | ScrapeInterval time.Duration `yaml:"scrape_interval"` |
| 24 | ScrapeTimeout time.Duration `yaml:"scrape_timeout"` |
| 25 | EvaluationInterval time.Duration `yaml:"evaluation_interval"` |
| 26 | } |
| 27 | |
| 28 | type PrometheusConfig struct { |
| 29 | RuleFiles []string `yaml:"rule_files"` |
| 30 | Global ConfigSectionGlobal `yaml:"global"` |
| 31 | } |
| 32 | |
| 33 | type PrometheusConfigResponse struct { |
| 34 | PrometheusResponse |
| 35 | Data v1.ConfigResult `json:"data"` |
| 36 | } |
| 37 | |
| 38 | type ConfigResult struct { |
| 39 | URI string |
| 40 | Config PrometheusConfig |
| 41 | } |
| 42 | |
| 43 | type configQuery struct { |
| 44 | prom *Prometheus |
| 45 | ctx context.Context |
| 46 | timestamp time.Time |
| 47 | cacheTTL time.Duration |
| 48 | } |
| 49 | |
| 50 | func (q configQuery) Run() queryResult { |
| 51 | slog.LogAttrs(q.ctx, slog.LevelDebug, "Getting prometheus configuration", slog.String("uri", q.prom.safeURI)) |
| 52 | |
| 53 | ctx, cancel := q.prom.requestContext(q.ctx) |
| 54 | defer cancel() |
| 55 | |
| 56 | var qr queryResult |
| 57 | |
| 58 | args := url.Values{} |
| 59 | resp, err := q.prom.doRequest(ctx, http.MethodGet, q.Endpoint(), args) |
| 60 | if err != nil { |
| 61 | qr.err = fmt.Errorf("failed to query Prometheus config: %w", err) |
| 62 | return qr |
| 63 | } |
| 64 | defer resp.Body.Close() |
| 65 | |
| 66 | if resp.StatusCode/100 != 2 { |
| 67 | qr.err = tryDecodingAPIError(resp) |
| 68 | return qr |
| 69 | } |
| 70 | |
| 71 | qr.value, err = parseConfig(resp.Body) |
| 72 | if err != nil { |
| 73 | prometheusQueryErrorsTotal.WithLabelValues(q.prom.name, APIPathConfig, errReason(err)).Inc() |
| 74 | qr.err = fmt.Errorf("failed to decode config data in %s response: %w", q.prom.safeURI, err) |
| 75 | } |
| 76 | return qr |
| 77 | } |
| 78 | |
| 79 | func (q configQuery) Endpoint() string { |
| 80 | return APIPathConfig |
| 81 | } |
| 82 | |
| 83 | func (q configQuery) String() string { |
| 84 | return APIPathConfig |
| 85 | } |
| 86 | |
| 87 | func (q configQuery) CacheKey() uint64 { |
| 88 | return hash(q.prom.unsafeURI, q.Endpoint()) |
| 89 | } |
| 90 | |
| 91 | func (q configQuery) CacheTTL() time.Duration { |
| 92 | return q.cacheTTL |
| 93 | } |
| 94 | |
| 95 | func (prom *Prometheus) Config(ctx context.Context, cacheTTL time.Duration) (*ConfigResult, error) { |
| 96 | slog.LogAttrs(ctx, slog.LevelDebug, "Scheduling Prometheus configuration query", slog.String("uri", prom.safeURI)) |
| 97 | |
| 98 | prom.locker.lock(APIPathConfig) |
| 99 | defer prom.locker.unlock(APIPathConfig) |
| 100 | |
| 101 | if cacheTTL == 0 { |
| 102 | cacheTTL = time.Minute |
| 103 | } |
| 104 | |
| 105 | resultChan := make(chan queryResult) |
| 106 | prom.queries <- queryRequest{ |
| 107 | query: configQuery{prom: prom, ctx: ctx, timestamp: time.Now(), cacheTTL: cacheTTL}, |
| 108 | result: resultChan, |
| 109 | } |
| 110 | |
| 111 | result := <-resultChan |
| 112 | if result.err != nil { |
| 113 | return nil, QueryError{err: result.err, msg: decodeError(result.err)} |
| 114 | } |
| 115 | |
| 116 | r := ConfigResult{ |
| 117 | URI: prom.publicURI, |
| 118 | Config: result.value.(PrometheusConfig), |
| 119 | } |
| 120 | |
| 121 | return &r, nil |
| 122 | } |
| 123 | |
| 124 | func parseConfig(r io.Reader) (cfg PrometheusConfig, err error) { |
| 125 | defer dummyReadAll(r) |
| 126 | |
| 127 | var data PrometheusConfigResponse |
| 128 | if err = json.UnmarshalRead(r, &data); err != nil { |
| 129 | return cfg, APIError{Status: data.Status, ErrorType: v1.ErrBadResponse, Err: "JSON parse error: " + err.Error()} |
| 130 | } |
| 131 | |
| 132 | if data.Status != "success" { |
| 133 | if data.Error == "" { |
| 134 | data.Error = "empty response object" |
| 135 | } |
| 136 | return cfg, APIError{Status: data.Status, ErrorType: decodeErrorType(data.ErrorType), Err: data.Error} |
| 137 | } |
| 138 | |
| 139 | if err = yaml.Unmarshal([]byte(data.Data.YAML), &cfg); err != nil { |
| 140 | return cfg, err |
| 141 | } |
| 142 | |
| 143 | if cfg.Global.ScrapeInterval == 0 { |
| 144 | cfg.Global.ScrapeInterval = time.Minute |
| 145 | } |
| 146 | if cfg.Global.ScrapeTimeout == 0 { |
| 147 | cfg.Global.ScrapeTimeout = time.Second * 10 |
| 148 | } |
| 149 | if cfg.Global.EvaluationInterval == 0 { |
| 150 | cfg.Global.EvaluationInterval = time.Minute |
| 151 | } |
| 152 | |
| 153 | return cfg, nil |
| 154 | } |
| 155 | |