From 281796fae27af4772ab818f914310e812b4719be Mon Sep 17 00:00:00 2001
From: Mario Rodriguez <mariorvinas@gmail.com>
Date: Wed, 23 Jun 2021 09:46:19 +0200
Subject: [PATCH] Add OTLP HTPP exporter support

---
 CHANGELOG.md                    |  2 ++
 docs/configuration-reference.md |  4 ++++
 pkg/tempo/config.go             | 14 ++++++++++++-
 pkg/tempo/config_test.go        | 37 +++++++++++++++++++++++++++++++++
 4 files changed, 56 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index db867e0a3db2..1689c3c9087a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 - [FEATURE] Add TLS config options for tempo `remote_write`s. (@mapno)
 
+- [FEATURE] Add support for OTLP HTTP trace exporting. (@mapno)
+
 - [ENHANCEMENT] The Grafana Agent Operator will now default to deploying
   the matching release version of the Grafana Agent instead of v0.14.0.
   (@rfratto)
diff --git a/docs/configuration-reference.md b/docs/configuration-reference.md
index 3a45f5125f51..dadf68de62dd 100644
--- a/docs/configuration-reference.md
+++ b/docs/configuration-reference.md
@@ -2038,6 +2038,10 @@ remote_write:
 
     # Controls whether compression is enabled.
     [ compression: <string> | default = "gzip" | supported = "none", "gzip"]
+    
+    # Controls what protocol to use when exporting traces.
+    # Only "grpc" is supported in Grafana Cloud.
+    [ protocol: <string> | default = "grpc" | supported = "grpc", "http" ]
 
     # Controls whether or not TLS is required.  See https://godoc.org/google.golang.org/grpc#WithInsecure
     [ insecure: <boolean> | default = false ]
diff --git a/pkg/tempo/config.go b/pkg/tempo/config.go
index 76e60576814e..85678de0b06c 100644
--- a/pkg/tempo/config.go
+++ b/pkg/tempo/config.go
@@ -23,6 +23,7 @@ import (
 	"go.opentelemetry.io/collector/config"
 	"go.opentelemetry.io/collector/config/configmodels"
 	"go.opentelemetry.io/collector/exporter/otlpexporter"
+	"go.opentelemetry.io/collector/exporter/otlphttpexporter"
 	"go.opentelemetry.io/collector/exporter/prometheusexporter"
 	"go.opentelemetry.io/collector/processor/attributesprocessor"
 	"go.opentelemetry.io/collector/processor/batchprocessor"
@@ -137,6 +138,8 @@ type InstanceConfig struct {
 const (
 	compressionNone = "none"
 	compressionGzip = "gzip"
+	protocolGRPC    = "grpc"
+	protocolHTTP    = "http"
 )
 
 // DefaultPushConfig holds the default settings for a PushConfig.
@@ -174,12 +177,14 @@ func (c *PushConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 // DefaultRemoteWriteConfig holds the default settings for a PushConfig.
 var DefaultRemoteWriteConfig = RemoteWriteConfig{
 	Compression: compressionGzip,
+	Protocol:    protocolGRPC,
 }
 
 // RemoteWriteConfig controls the configuration of an exporter
 type RemoteWriteConfig struct {
 	Endpoint    string `yaml:"endpoint,omitempty"`
 	Compression string `yaml:"compression,omitempty"`
+	Protocol    string `yaml:"protocol,omitempty"`
 	Insecure    bool   `yaml:"insecure,omitempty"`
 	// Deprecated
 	InsecureSkipVerify bool                   `yaml:"insecure_skip_verify,omitempty"`
@@ -341,7 +346,13 @@ func (c *InstanceConfig) exporters() (map[string]interface{}, error) {
 		if err != nil {
 			return nil, err
 		}
-		exporterName := fmt.Sprintf("otlp/%d", i)
+		var exporterName string
+		switch remoteWriteConfig.Protocol {
+		case protocolGRPC:
+			exporterName = fmt.Sprintf("otlp/%d", i)
+		case protocolHTTP:
+			exporterName = fmt.Sprintf("otlphttp/%d", i)
+		}
 		exporters[exporterName] = exporter
 	}
 	return exporters, nil
@@ -637,6 +648,7 @@ func tracingFactories() (component.Factories, error) {
 
 	exporters, err := component.MakeExporterFactoryMap(
 		otlpexporter.NewFactory(),
+		otlphttpexporter.NewFactory(),
 		loadbalancingexporter.NewFactory(),
 		prometheusexporter.NewFactory(),
 		remotewriteexporter.NewFactory(),
diff --git a/pkg/tempo/config_test.go b/pkg/tempo/config_test.go
index 3851a7645341..a80c79e3fe4f 100644
--- a/pkg/tempo/config_test.go
+++ b/pkg/tempo/config_test.go
@@ -736,6 +736,43 @@ service:
       exporters: ["otlp/0"]
       processors: []
       receivers: ["jaeger"]
+`,
+		},
+		{
+			name: "otlp http & grpc exporters",
+			cfg: `
+receivers:
+  jaeger:
+    protocols:
+      grpc:
+remote_write:
+  - endpoint: example.com:12345
+    protocol: http 
+  - endpoint: example.com:12345
+    protocol: grpc
+`,
+			expectedConfig: `
+receivers:
+  jaeger:
+    protocols:
+      grpc:
+exporters:
+  otlphttp/0:
+    endpoint: example.com:12345
+    compression: gzip
+    retry_on_failure:
+      max_elapsed_time: 60s
+  otlp/1:
+    endpoint: example.com:12345
+    compression: gzip
+    retry_on_failure:
+      max_elapsed_time: 60s
+service:
+  pipelines:
+    traces:
+      exporters: ["otlphttp/0", "otlp/1"]
+      processors: []
+      receivers: ["jaeger"]
 `,
 		},
 	}