config: add OTLP configuration types

Signed-off-by: Hank Donnay <[email protected]>

Documentation/reference/config.md

@@ -62,12 +62,19 @@ The output of that command is also not currently suitable to be used to "compile
 [rfc7386]: https://datatracker.ietf.org/doc/html/rfc7386
 [rfc6902]: https://datatracker.ietf.org/doc/html/rfc6902
 
-## Configuration Reference
+## Deprecations and Changes
 
-Please see the [go module documentation][godoc_config] for additional documentation on defaults and use.
 Starting in version `4.7.0`, unknown keys are disallowed.
 Configurations that looked valid previously and loaded fine may now cause Clair to refuse to start.
 
+In version `4.8.0`, using Jaeger for trace submission was deprecated.
+Configurations that use Jaeger will print a warning.
+In future versions, using Jaeger may cause an error.
+
+## Configuration Reference
+
+Please see the [go module documentation][godoc_config] for additional documentation on defaults and use.
+
 [godoc_config]: https://pkg.go.dev/github.com/quay/clair/config
 
 ```
@@ -121,6 +128,9 @@ trace:
         service_name: ""
         tags: nil
         buffer_max: 0
+    otlp:
+	  http: {}
+      grpc: {}
 metrics:
     name: ""
     prometheus:
@@ -140,6 +150,7 @@ more information.
 # `$.auth.keyserver`
 # `$.auth.keyserver.api`
 # `$.auth.keyserver.intraservice`
+# `$.metrics.otlp`
 -->
 
 ### `$.http_listen_addr`
@@ -599,18 +610,21 @@ JWT claim.
 Defines distributed tracing configuration based on OpenTelemetry.
 
 #### `$.trace.name`
-a string value
-
-The name of the application traces will belong to.
+Which submission format to use, one of:
+- jaeger
+- otlp
 
 #### `$.trace.probability`
 a float value
 
 The probability a trace will occur.
 
-#### `$.trace.jaeger`
+### `$.trace.jaeger`
 Defines values for Jaeger tracing.
 
+***NOTE***: Jaeger has deprecated using the `jaeger` protocol and encouraging users to migrate to OTLP,
+which Jaeger can ingest natively.
+
 #### `$.trace.jaeger.agent`
 Defines values for configuring delivery to a Jaeger agent.
 
@@ -642,6 +656,75 @@ a mapping of a string to a string
 #### `$.trace.jaeger.buffer_max`
 an integer value
 
+### `$.trace.otlp`
+Configuration for OTLP traces.
+
+Only one of the `http` or `grpc` keys should be provided.
+
+#### `$.trace.otlp.http`
+Configuration for OTLP traces submitted by HTTP.
+
+##### `$.trace.otlp.http.url_path`
+Request path to use for submissions.
+Defaults to `/v1/traces`.
+
+##### `$.trace.otlp.http.compression`
+Compression for payloads.
+One of:
+- gzip
+- none
+
+##### `$.trace.otlp.http.endpoint`
+`Host:port` for submission. Defaults to `localhost:4318`.
+
+##### `$.trace.otlp.http.headers`
+Key-value pairs of additional headers for submissions.
+
+##### `$.trace.otlp.http.insecure`
+Use HTTP instead of HTTPS.
+
+##### `$.trace.otlp.http.timeout`
+Maximum of of time for a trace submission.
+
+##### `$.trace.otlp.http.client_tls.cert`
+Client certificate for connection.
+
+##### `$.trace.otlp.http.client_tls.key`
+Key for the certificate specified in `cert`.
+
+#### `$.trace.otlp.grpc`
+Configuration for OTLP traces submitted by gRPC.
+
+##### `$.trace.otlp.grpc.reconnect`
+Sets the minimum time between connection attempts.
+
+##### `$.trace.otlp.grpc.service_config`
+A string containing a JSON-format gRPC service config.
+
+##### `$.trace.otlp.grpc.compression`
+Compression for payloads.
+One of:
+- gzip
+- none
+
+##### `$.trace.otlp.grpc.endpoint`
+`Host:port` for submission. Defaults to `localhost:4317`.
+
+##### `$.trace.otlp.grpc.headers`
+Key-value pairs of additional headers for submissions.
+
+##### `$.trace.otlp.grpc.insecure`
+Do not verify the server certificate.
+
+##### `$.trace.otlp.grpc.timeout`
+Maximum of of time for a trace submission.
+
+##### `$.trace.otlp.grpc.client_tls.cert`
+Client certificate for connection.
+
+##### `$.trace.otlp.grpc.client_tls.key`
+Key for the certificate specified in `cert`.
+
 ### `$.metrics`
 Defines distributed tracing configuration based on OpenTelemetry.
 

config/doc.go

@@ -1,7 +1,8 @@
 // Package config is the configuration package for Clair's binaries. See the
-// Config type for the main entry point.
+// [Config] type for the main entry point.
 //
-// It's currently meant for reading configs and tested against YAML and JSON.
+// It's currently meant for reading configurations and tested against YAML and
+// JSON.
 //
 // # Version Scheme
 //
@@ -16,7 +17,7 @@
 // changes on a program importing the module.
 package config
 
-// This pakcage can't use "omitempty" tags on slices because "not present" and
+// This package can't use "omitempty" tags on slices because "not present" and
 // "empty" aren't distinguished. This would be much easier if code didn't
 // serialize our config struct. It's impossible to implement custom YAML
 // marshalling without importing the yaml.v3 package.

config/introspection.go

@@ -5,18 +5,22 @@ import "fmt"
 // Trace specifies how to configure Clair's tracing support.
 //
 // The "Name" key must match the provider to use.
-//
-// Currently, only "jaeger" is supported.
 type Trace struct {
-	Name        string   `yaml:"name" json:"name"`
-	Probability *float64 `yaml:"probability,omitempty" json:"probability,omitempty"`
-	Jaeger      Jaeger   `yaml:"jaeger,omitempty" json:"jaeger,omitempty"`
+	Name        string    `yaml:"name" json:"name"`
+	Probability *float64  `yaml:"probability,omitempty" json:"probability,omitempty"`
+	Jaeger      Jaeger    `yaml:"jaeger,omitempty" json:"jaeger,omitempty"`
+	OTLP        TraceOTLP `yaml:"otlp,omitempty" json:"otlp,omitempty"`
 }
 
 func (t *Trace) lint() ([]Warning, error) {
 	switch t.Name {
 	case "":
+	case "otlp":
 	case "jaeger":
+		return []Warning{{
+			path: ".name",
+			msg:  `trace provider "jaeger" is deprecated; migrate to "otlp"`,
+		}}, nil
 	default:
 		return []Warning{{
 			path: ".name",
@@ -27,6 +31,11 @@ func (t *Trace) lint() ([]Warning, error) {
 }
 
 // Jaeger specific distributed tracing configuration.
+//
+// Deprecated: The Jaeger project recommends using their OTLP ingestion support
+// and the OpenTelemetry exporter for Jaeger has since been removed. Users
+// should migrate to OTLP. Clair may refuse to start when configured to emit
+// Jaeger traces.
 type Jaeger struct {
 	Tags  map[string]string `yaml:"tags,omitempty" json:"tags,omitempty"`
 	Agent struct {
@@ -44,16 +53,20 @@ type Jaeger struct {
 // Metrics specifies how to configure Clair's metrics exporting.
 //
 // The "Name" key must match the provider to use.
-//
-// Currently, only "prometheus" is supported.
 type Metrics struct {
-	Prometheus Prometheus `yaml:"prometheus,omitempty" json:"prometheus,omitempty"`
 	Name       string     `yaml:"name" json:"name"`
+	Prometheus Prometheus `yaml:"prometheus,omitempty" json:"prometheus,omitempty"`
+	OTLP       MetricOTLP `yaml:"otlp,omitempty" json:"otlp,omitempty"`
 }
 
 func (m *Metrics) lint() ([]Warning, error) {
 	switch m.Name {
 	case "":
+	case "otlp":
+		return []Warning{{
+			path: ".name",
+			msg:  `please consult the documentation for the status of metrics via "otlp"`,
+		}}, nil
 	case "prometheus":
 	default:
 		return []Warning{{