diff options
Diffstat (limited to 'vendor/go.opentelemetry.io/otel/sdk/resource/container.go')
-rw-r--r-- | vendor/go.opentelemetry.io/otel/sdk/resource/container.go | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/vendor/go.opentelemetry.io/otel/sdk/resource/container.go b/vendor/go.opentelemetry.io/otel/sdk/resource/container.go new file mode 100644 index 000000000..318dcf82f --- /dev/null +++ b/vendor/go.opentelemetry.io/otel/sdk/resource/container.go @@ -0,0 +1,100 @@ +// Copyright The OpenTelemetry 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 // import "go.opentelemetry.io/otel/sdk/resource" + +import ( + "bufio" + "context" + "errors" + "io" + "os" + "regexp" + + semconv "go.opentelemetry.io/otel/semconv/v1.17.0" +) + +type containerIDProvider func() (string, error) + +var ( + containerID containerIDProvider = getContainerIDFromCGroup + cgroupContainerIDRe = regexp.MustCompile(`^.*/(?:.*-)?([0-9a-f]+)(?:\.|\s*$)`) +) + +type cgroupContainerIDDetector struct{} + +const cgroupPath = "/proc/self/cgroup" + +// Detect returns a *Resource that describes the id of the container. +// If no container id found, an empty resource will be returned. +func (cgroupContainerIDDetector) Detect(ctx context.Context) (*Resource, error) { + containerID, err := containerID() + if err != nil { + return nil, err + } + + if containerID == "" { + return Empty(), nil + } + return NewWithAttributes(semconv.SchemaURL, semconv.ContainerID(containerID)), nil +} + +var ( + defaultOSStat = os.Stat + osStat = defaultOSStat + + defaultOSOpen = func(name string) (io.ReadCloser, error) { + return os.Open(name) + } + osOpen = defaultOSOpen +) + +// getContainerIDFromCGroup returns the id of the container from the cgroup file. +// If no container id found, an empty string will be returned. +func getContainerIDFromCGroup() (string, error) { + if _, err := osStat(cgroupPath); errors.Is(err, os.ErrNotExist) { + // File does not exist, skip + return "", nil + } + + file, err := osOpen(cgroupPath) + if err != nil { + return "", err + } + defer file.Close() + + return getContainerIDFromReader(file), nil +} + +// getContainerIDFromReader returns the id of the container from reader. +func getContainerIDFromReader(reader io.Reader) string { + scanner := bufio.NewScanner(reader) + for scanner.Scan() { + line := scanner.Text() + + if id := getContainerIDFromLine(line); id != "" { + return id + } + } + return "" +} + +// getContainerIDFromLine returns the id of the container from one string line. +func getContainerIDFromLine(line string) string { + matches := cgroupContainerIDRe.FindStringSubmatch(line) + if len(matches) <= 1 { + return "" + } + return matches[1] +} |