Add resource injection tool

auto/auto.go

@@ -24,7 +24,7 @@ import (
 
 // Detect sequentially runs resource detection from environment varibales, AWS, and GCP.
 func Detect(ctx context.Context) (*resource.Resource, error) {
-	return resource.ChainedDetector(
+	return resource.MultiDetector(
 		resource.FromEnv,
 		gcp.DetectGCEInstance,
 		aws.DetectEC2Instance,

aws/aws.go

@@ -34,7 +34,7 @@ func DetectEC2Instance(context.Context) (*resource.Resource, error) {
 	}
 	return &resource.Resource{
 		Type: resourcekeys.AWSTypeEC2Instance,
-		Tags: map[string]string{
+		Labels: map[string]string{
 			resourcekeys.AWSKeyEC2Region:     doc.Region,
 			resourcekeys.AWSKeyEC2AccountID:  doc.AccountID,
 			resourcekeys.AWSKeyEC2InstanceID: doc.InstanceID,

cmd/ocdiscover/.gitignore

@@ -0,0 +1 @@
+ocdiscover

cmd/ocdiscover/README.md

@@ -0,0 +1,22 @@
+# ocdiscover
+
+This tool runs all known resource discovery mechanisms in the repository and
+returns the result encoded in the well-known environment variables.
+
+## Installation
+
+Install the `ocdiscover` tool using:
+
+```bash
+go get contrib.go.opencensus.io/resource/cmd/ocdiscover
+```
+
+## Usage
+
+To run an arbitrary command with resource information provided via the
+OpenCensus environment varibales use:
+
+```bash
+env $(ocdiscovery) <command> [ <arg> ... ]
+```
+

cmd/ocdiscover/main.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"contrib.go.opencensus.io/resource/auto"
+	"go.opencensus.io/resource"
+)
+
+func main() {
+	res, err := auto.Detect(context.Background())
+	if err != nil {
+		log.Fatalf("detecting resource info failed: %s", err)
+	}
+	fmt.Printf("%s='%s' %s='%s'\n", resource.EnvVarType, res.Type, resource.EnvVarLabels, resource.EncodeLabels(res.Labels))
+}

gcp/gcp.go

@@ -29,25 +29,25 @@ func DetectGCEInstance(context.Context) (*resource.Resource, error) {
 		return nil, nil
 	}
 	res := &resource.Resource{
-		Type: resourcekeys.GCPTypeGCEInstance,
-		Tags: map[string]string{},
+		Type:   resourcekeys.GCPTypeGCEInstance,
+		Labels: map[string]string{},
 	}
 	instanceID, err := metadata.InstanceID()
 	logError(err)
 	if instanceID != "" {
-		res.Tags[resourcekeys.GCPKeyGCEInstanceID] = instanceID
+		res.Labels[resourcekeys.GCPKeyGCEInstanceID] = instanceID
 	}
 
 	projectID, err := metadata.ProjectID()
 	logError(err)
 	if projectID != "" {
-		res.Tags[resourcekeys.GCPKeyGCEProjectID] = projectID
+		res.Labels[resourcekeys.GCPKeyGCEProjectID] = projectID
 	}
 
 	zone, err := metadata.Zone()
 	logError(err)
 	if zone != "" {
-		res.Tags[resourcekeys.GCPKeyGCEZone] = zone
+		res.Labels[resourcekeys.GCPKeyGCEZone] = zone
 	}
 
 	return res, nil