diff options
Diffstat (limited to 'vendor/go.opencensus.io/resource/resource.go')
| -rw-r--r-- | vendor/go.opencensus.io/resource/resource.go | 164 |
1 files changed, 0 insertions, 164 deletions
diff --git a/vendor/go.opencensus.io/resource/resource.go b/vendor/go.opencensus.io/resource/resource.go deleted file mode 100644 index b1764e1..0000000 --- a/vendor/go.opencensus.io/resource/resource.go +++ /dev/null @@ -1,164 +0,0 @@ -// Copyright 2018, OpenCensus Authors -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// Package resource provides functionality for resource, which capture -// identifying information about the entities for which signals are exported. -package resource - -import ( - "context" - "fmt" - "os" - "regexp" - "sort" - "strconv" - "strings" -) - -// Environment variables used by FromEnv to decode a resource. -const ( - EnvVarType = "OC_RESOURCE_TYPE" - EnvVarLabels = "OC_RESOURCE_LABELS" -) - -// Resource describes an entity about which identifying information and metadata is exposed. -// For example, a type "k8s.io/container" may hold labels describing the pod name and namespace. -type Resource struct { - Type string - Labels map[string]string -} - -// EncodeLabels encodes a labels map to a string as provided via the OC_RESOURCE_LABELS environment variable. -func EncodeLabels(labels map[string]string) string { - sortedKeys := make([]string, 0, len(labels)) - for k := range labels { - sortedKeys = append(sortedKeys, k) - } - sort.Strings(sortedKeys) - - s := "" - for i, k := range sortedKeys { - if i > 0 { - s += "," - } - s += k + "=" + strconv.Quote(labels[k]) - } - return s -} - -var labelRegex = regexp.MustCompile(`^\s*([[:ascii:]]{1,256}?)=("[[:ascii:]]{0,256}?")\s*,`) - -// DecodeLabels decodes a serialized label map as used in the OC_RESOURCE_LABELS variable. -// A list of labels of the form `<key1>="<value1>",<key2>="<value2>",...` is accepted. -// Domain names and paths are accepted as label keys. -// Most users will want to use FromEnv instead. -func DecodeLabels(s string) (map[string]string, error) { - m := map[string]string{} - // Ensure a trailing comma, which allows us to keep the regex simpler - s = strings.TrimRight(strings.TrimSpace(s), ",") + "," - - for len(s) > 0 { - match := labelRegex.FindStringSubmatch(s) - if len(match) == 0 { - return nil, fmt.Errorf("invalid label formatting, remainder: %s", s) - } - v := match[2] - if v == "" { - v = match[3] - } else { - var err error - if v, err = strconv.Unquote(v); err != nil { - return nil, fmt.Errorf("invalid label formatting, remainder: %s, err: %s", s, err) - } - } - m[match[1]] = v - - s = s[len(match[0]):] - } - return m, nil -} - -// FromEnv is a detector that loads resource information from the OC_RESOURCE_TYPE -// and OC_RESOURCE_labelS environment variables. -func FromEnv(context.Context) (*Resource, error) { - res := &Resource{ - Type: strings.TrimSpace(os.Getenv(EnvVarType)), - } - labels := strings.TrimSpace(os.Getenv(EnvVarLabels)) - if labels == "" { - return res, nil - } - var err error - if res.Labels, err = DecodeLabels(labels); err != nil { - return nil, err - } - return res, nil -} - -var _ Detector = FromEnv - -// merge resource information from b into a. In case of a collision, a takes precedence. -func merge(a, b *Resource) *Resource { - if a == nil { - return b - } - if b == nil { - return a - } - res := &Resource{ - Type: a.Type, - Labels: map[string]string{}, - } - if res.Type == "" { - res.Type = b.Type - } - for k, v := range b.Labels { - res.Labels[k] = v - } - // Labels from resource a overwrite labels from resource b. - for k, v := range a.Labels { - res.Labels[k] = v - } - return res -} - -// Detector attempts to detect resource information. -// If the detector cannot find resource information, the returned resource is nil but no -// error is returned. -// An error is only returned on unexpected failures. -type Detector func(context.Context) (*Resource, error) - -// MultiDetector returns a Detector that calls all input detectors in order and -// merges each result with the previous one. In case a type of label key is already set, -// the first set value is takes precedence. -// It returns on the first error that a sub-detector encounters. -func MultiDetector(detectors ...Detector) Detector { - return func(ctx context.Context) (*Resource, error) { - return detectAll(ctx, detectors...) - } -} - -// detectall calls all input detectors sequentially an merges each result with the previous one. -// It returns on the first error that a sub-detector encounters. -func detectAll(ctx context.Context, detectors ...Detector) (*Resource, error) { - var res *Resource - for _, d := range detectors { - r, err := d(ctx) - if err != nil { - return nil, err - } - res = merge(res, r) - } - return res, nil -} |