[receiver/github] add tracing via webhook skeleton (open-telemetry#36632)

#### Description
Adds the basic webhook configuration and logic, with a health check, to
enable development of tracings (and logs) in future iterations.

#### Testing
Added basic tests and built the component to test that the health check
endpoint, when tracing is enabled, operates correctly.

#### Documentation
Because this portion of the receiver is in development, and adds only
the skeleton, no docs have been added yet.

Author: adrielp

Diff for: .chloggen/gh-trace-skeleton.yaml

@@ -0,0 +1,30 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: githubreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Adds webhook skeleton to GitHub receiver to receive events from GitHub for tracing.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [27460]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext: |
+  This PR adds a skeleton for the GitHub receiver to receive events from GitHub
+  for tracing via a webhook. The trace portion of this receiver will run and
+  respond to GET requests for the health check only.
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [user]

Diff for: receiver/githubreceiver/README.md

@@ -3,18 +3,18 @@
 <!-- status autogenerated section -->
 | Status        |           |
 | ------------- |-----------|
-| Stability     | [alpha]: metrics   |
+| Stability     | [development]: traces   |
+|               | [alpha]: metrics   |
 | Distributions | [contrib] |
 | Issues        | [![Open issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aopen%20label%3Areceiver%2Fgithub%20&label=open&color=orange&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aopen+is%3Aissue+label%3Areceiver%2Fgithub) [![Closed issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aclosed%20label%3Areceiver%2Fgithub%20&label=closed&color=blue&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aclosed+is%3Aissue+label%3Areceiver%2Fgithub) |
 | [Code Owners](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/CONTRIBUTING.md#becoming-a-code-owner)    | [@adrielp](https://www.github.com/adrielp), [@andrzej-stencel](https://www.github.com/andrzej-stencel), [@crobert-1](https://www.github.com/crobert-1), [@TylerHelmuth](https://www.github.com/TylerHelmuth) |
 
+[development]: https://github.com/open-telemetry/opentelemetry-collector/blob/main/docs/component-stability.md#development
 [alpha]: https://github.com/open-telemetry/opentelemetry-collector/blob/main/docs/component-stability.md#alpha
 [contrib]: https://github.com/open-telemetry/opentelemetry-collector-releases/tree/main/distributions/otelcol-contrib
 <!-- end autogenerated section -->
 
-The GitHub receiver receives data from [GitHub](https://github.com). As a
-starting point it scrapes metrics from repositories but will be extended to
-include traces and logs.
+The GitHub receiver receives data from [GitHub](https://github.com).
 
 The current default set of metrics can be found in
 [documentation.md](./documentation.md).
@@ -26,13 +26,13 @@ engineering practices.
 [doracap]: https://dora.dev/capabilities/
 [dorafour]: https://dora.dev/guides/dora-metrics-four-keys/
 
-## Getting Started
+## Metrics - Getting Started
 
 The collection interval is common to all scrapers and is set to 30 seconds by default.
 
 > Note: Generally speaking, if the vendor allows for anonymous API calls, then you
 > won't have to configure any authentication, but you may only see public repositories
-> and organizations. You may run into significantly more rate limiting.
+> and organizations. You may also run into significantly more rate limiting.
 
 ```yaml
 github:
@@ -92,3 +92,56 @@ For additional context on GitHub scraper limitations and inner workings please
 see the [Scraping README][ghsread].
 
 [ghsread]: internal/scraper/githubscraper/README.md#github-limitations
+
+## Traces - Getting Started
+
+Workflow tracing support is actively being added to the GitHub receiver.
+This is accomplished through the processing of GitHub Actions webhook
+events for workflows and jobs. The [`workflow_job`][wjob] and
+[`workflow_run`][wrun] event payloads are then constructed into `trace`
+telemetry.
+
+Each GitHub Action workflow or job, along with its steps, are converted
+into trace spans, allowing the observation of workflow execution times,
+success, and failure rates.
+
+### Configuration
+
+**IMPORTANT: At this time the tracing portion of this receiver only serves a health check endpoint.**
+
+The WebHook configuration exposes the following settings:
+
+* `endpoint`: (default = `localhost:8080`) - The address and port to bind the WebHook to.
+* `path`: (default = `/events`) - The path for Action events to be sent to.
+* `health_path`: (default = `/health`) - The path for health checks.
+* `secret`: (optional) - The secret used to [validates the payload][valid].
+* `required_header`: (optional) - The required header key and value for incoming requests.
+
+The WebHook configuration block also accepts all the [confighttp][cfghttp]
+settings.
+
+An example configuration is as follows:
+
+```yaml
+receivers:
+    github:
+        scrapers:
+            ... <scraper configuration>: # Scraper configurations are required until Tracing functionality is complete.
+        webhook:
+            endpoint: localhost:19418
+            path: /events
+            health_path: /health
+            secret: ${env:SECRET_STRING_VAR}
+            required_header:
+                key: "X-GitHub-Event"
+                value: "action"
+```
+
+For tracing, all configuration is set under the `webhook` key. The full set
+of exposed configuration values can be found in [`config.go`][config.go].
+
+[wjob]: https://docs.github.com/en/webhooks/webhook-events-and-payloads#workflow_job
+[wrun]: https://docs.github.com/en/webhooks/webhook-events-and-payloads#workflow_run
+[valid]: https://docs.github.com/en/webhooks/using-webhooks/validating-webhook-deliveries
+[config.go] ./config.go
+[cfghttp]: https://pkg.go.dev/go.opentelemetry.io/collector/config/confighttp#ServerConfig

Diff for: receiver/githubreceiver/config.go

@@ -6,10 +6,13 @@ package githubreceiver // import "github.com/open-telemetry/opentelemetry-collec
 import (
 	"errors"
 	"fmt"
+	"time"
 
 	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/config/confighttp"
 	"go.opentelemetry.io/collector/confmap"
 	"go.opentelemetry.io/collector/receiver/scraperhelper"
+	"go.uber.org/multierr"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/receiver/githubreceiver/internal"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/receiver/githubreceiver/internal/metadata"
@@ -24,19 +27,62 @@ type Config struct {
 	scraperhelper.ControllerConfig `mapstructure:",squash"`
 	Scrapers                       map[string]internal.Config `mapstructure:"scrapers"`
 	metadata.MetricsBuilderConfig  `mapstructure:",squash"`
+	WebHook                        WebHook `mapstructure:"webhook"`
+}
+
+type WebHook struct {
+	confighttp.ServerConfig `mapstructure:",squash"` // squash ensures fields are correctly decoded in embedded struct
+	Path                    string                   `mapstructure:"path"`            // path for data collection. Default is /events
+	HealthPath              string                   `mapstructure:"health_path"`     // path for health check api. Default is /health_check
+	RequiredHeader          RequiredHeader           `mapstructure:"required_header"` // optional setting to set a required header for all requests to have
+	Secret                  string                   `mapstructure:"secret"`          // secret for webhook
+}
+
+type RequiredHeader struct {
+	Key   string `mapstructure:"key"`
+	Value string `mapstructure:"value"`
 }
 
 var (
 	_ component.Config    = (*Config)(nil)
 	_ confmap.Unmarshaler = (*Config)(nil)
+
+	errMissingEndpointFromConfig   = errors.New("missing receiver server endpoint from config")
+	errReadTimeoutExceedsMaxValue  = errors.New("the duration specified for read_timeout exceeds the maximum allowed value of 10s")
+	errWriteTimeoutExceedsMaxValue = errors.New("the duration specified for write_timeout exceeds the maximum allowed value of 10s")
+	errRequiredHeader              = errors.New("both key and value are required to assign a required_header")
+	errRequireOneScraper           = errors.New("must specify at least one scraper")
 )
 
 // Validate the configuration passed through the OTEL config.yaml
 func (cfg *Config) Validate() error {
+	var errs error
+
+	// For now, scrapers are required to be defined in the config. As tracing
+	// and other signals are added, this requirement will change.
 	if len(cfg.Scrapers) == 0 {
-		return errors.New("must specify at least one scraper")
+		errs = multierr.Append(errs, errRequireOneScraper)
 	}
-	return nil
+
+	maxReadWriteTimeout, _ := time.ParseDuration("10s")
+
+	if cfg.WebHook.ServerConfig.Endpoint == "" {
+		errs = multierr.Append(errs, errMissingEndpointFromConfig)
+	}
+
+	if cfg.WebHook.ServerConfig.ReadTimeout > maxReadWriteTimeout {
+		errs = multierr.Append(errs, errReadTimeoutExceedsMaxValue)
+	}
+
+	if cfg.WebHook.ServerConfig.WriteTimeout > maxReadWriteTimeout {
+		errs = multierr.Append(errs, errWriteTimeoutExceedsMaxValue)
+	}
+
+	if (cfg.WebHook.RequiredHeader.Key != "" && cfg.WebHook.RequiredHeader.Value == "") || (cfg.WebHook.RequiredHeader.Value != "" && cfg.WebHook.RequiredHeader.Key == "") {
+		errs = multierr.Append(errs, errRequiredHeader)
+	}
+
+	return errs
 }
 
 // Unmarshal a config.Parser into the config struct.

Diff for: receiver/githubreceiver/config_test.go

@@ -11,6 +11,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/config/confighttp"
 	"go.opentelemetry.io/collector/confmap"
 	"go.opentelemetry.io/collector/otelcol/otelcoltest"
 	"go.opentelemetry.io/collector/receiver/scraperhelper"
@@ -26,6 +27,7 @@ func TestLoadConfig(t *testing.T) {
 
 	factory := NewFactory()
 	factories.Receivers[metadata.Type] = factory
+
 	// https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/33594
 	// nolint:staticcheck
 	cfg, err := otelcoltest.LoadConfigAndValidate(filepath.Join("testdata", "config.yaml"), factories)
@@ -36,12 +38,27 @@ func TestLoadConfig(t *testing.T) {
 	assert.Len(t, cfg.Receivers, 2)
 
 	r0 := cfg.Receivers[component.NewID(metadata.Type)]
-	defaultConfigGitHubScraper := factory.CreateDefaultConfig()
-	defaultConfigGitHubScraper.(*Config).Scrapers = map[string]internal.Config{
+	defaultConfigGitHubReceiver := factory.CreateDefaultConfig()
+
+	defaultConfigGitHubReceiver.(*Config).Scrapers = map[string]internal.Config{
 		metadata.Type.String(): (&githubscraper.Factory{}).CreateDefaultConfig(),
 	}
 
-	assert.Equal(t, defaultConfigGitHubScraper, r0)
+	defaultConfigGitHubReceiver.(*Config).WebHook = WebHook{
+		ServerConfig: confighttp.ServerConfig{
+			Endpoint:     "localhost:8080",
+			ReadTimeout:  500 * time.Millisecond,
+			WriteTimeout: 500 * time.Millisecond,
+		},
+		Path:       "some/path",
+		HealthPath: "health/path",
+		RequiredHeader: RequiredHeader{
+			Key:   "key-present",
+			Value: "value-present",
+		},
+	}
+
+	assert.Equal(t, defaultConfigGitHubReceiver, r0)
 
 	r1 := cfg.Receivers[component.NewIDWithName(metadata.Type, "customname")].(*Config)
 	expectedConfig := &Config{
@@ -52,6 +69,19 @@ func TestLoadConfig(t *testing.T) {
 		Scrapers: map[string]internal.Config{
 			metadata.Type.String(): (&githubscraper.Factory{}).CreateDefaultConfig(),
 		},
+		WebHook: WebHook{
+			ServerConfig: confighttp.ServerConfig{
+				Endpoint:     "localhost:8080",
+				ReadTimeout:  500 * time.Millisecond,
+				WriteTimeout: 500 * time.Millisecond,
+			},
+			Path:       "some/path",
+			HealthPath: "health/path",
+			RequiredHeader: RequiredHeader{
+				Key:   "key-present",
+				Value: "value-present",
+			},
+		},
 	}
 
 	assert.Equal(t, expectedConfig, r1)

Diff for: receiver/githubreceiver/factory.go

@@ -7,8 +7,10 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"time"
 
 	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/config/confighttp"
 	"go.opentelemetry.io/collector/consumer"
 	"go.opentelemetry.io/collector/receiver"
 	"go.opentelemetry.io/collector/receiver/scraperhelper"
@@ -21,6 +23,14 @@ import (
 
 // This file implements a factory for the github receiver
 
+const (
+	defaultReadTimeout  = 500 * time.Millisecond
+	defaultWriteTimeout = 500 * time.Millisecond
+	defaultPath         = "/events"
+	defaultHealthPath   = "/health"
+	defaultEndpoint     = "localhost:8080"
+)
+
 var (
 	scraperFactories = map[string]internal.ScraperFactory{
 		metadata.Type.String(): &githubscraper.Factory{},
@@ -35,6 +45,7 @@ func NewFactory() receiver.Factory {
 		metadata.Type,
 		createDefaultConfig,
 		receiver.WithMetrics(createMetricsReceiver, metadata.MetricsStability),
+		receiver.WithTraces(createTracesReceiver, metadata.TracesStability),
 	)
 }
 
@@ -51,12 +62,15 @@ func getScraperFactory(key string) (internal.ScraperFactory, bool) {
 func createDefaultConfig() component.Config {
 	return &Config{
 		ControllerConfig: scraperhelper.NewDefaultControllerConfig(),
-		// TODO: metrics builder configuration may need to be in each sub scraper,
-		// TODO: for right now setting here because the metrics in this receiver will apply to all
-		// TODO: scrapers defined as a common set of github
-		// TODO: aqp completely remove these comments if the metrics build config
-		// needs to be defined in each scraper
-		// MetricsBuilderConfig: metadata.DefaultMetricsBuilderConfig(),
+		WebHook: WebHook{
+			ServerConfig: confighttp.ServerConfig{
+				Endpoint:     defaultEndpoint,
+				ReadTimeout:  defaultReadTimeout,
+				WriteTimeout: defaultWriteTimeout,
+			},
+			Path:       defaultPath,
+			HealthPath: defaultHealthPath,
+		},
 	}
 }
 
@@ -87,6 +101,21 @@ func createMetricsReceiver(
 	)
 }
 
+func createTracesReceiver(
+	_ context.Context,
+	params receiver.Settings,
+	cfg component.Config,
+	consumer consumer.Traces,
+) (receiver.Traces, error) {
+	// check that the configuration is valid
+	conf, ok := cfg.(*Config)
+	if !ok {
+		return nil, errConfigNotValid
+	}
+
+	return newTracesReceiver(params, conf, consumer)
+}
+
 func createAddScraperOpts(
 	ctx context.Context,
 	params receiver.Settings,

Diff for: receiver/githubreceiver/factory_test.go

@@ -30,11 +30,11 @@ func TestCreateDefaultConfig(t *testing.T) {
 
 func TestCreateReceiver(t *testing.T) {
 	factory := NewFactory()
-	cfg := factory.CreateDefaultConfig()
+	cfg := factory.CreateDefaultConfig().(*Config)
 
 	tReceiver, err := factory.CreateTraces(context.Background(), creationSet, cfg, consumertest.NewNop())
-	assert.Equal(t, err, pipeline.ErrSignalNotSupported)
-	assert.Nil(t, tReceiver)
+	assert.NoError(t, err)
+	assert.NotNil(t, tReceiver)
 
 	mReceiver, err := factory.CreateMetrics(context.Background(), creationSet, cfg, consumertest.NewNop())
 	assert.NoError(t, err)