From ce0bd1ea8b8937bcddec56cdc2941402309817dc Mon Sep 17 00:00:00 2001
From: Hugo Labrador <labkode@users.noreply.github.com>
Date: Wed, 7 Feb 2024 17:03:17 +0100
Subject: [PATCH] Add pprof http service and demote prom interceptor to not run
 by default (#4508)

* add pprof http service
* disable loading prom as default interceptor
---
 changelog/unreleased/pprof.md           |  6 ++
 cmd/revad/runtime/http.go               |  2 -
 internal/http/services/loader/loader.go |  1 +
 internal/http/services/pprof/pprof.go   | 80 +++++++++++++++++++++++++
 4 files changed, 87 insertions(+), 2 deletions(-)
 create mode 100644 changelog/unreleased/pprof.md
 create mode 100644 internal/http/services/pprof/pprof.go

diff --git a/changelog/unreleased/pprof.md b/changelog/unreleased/pprof.md
new file mode 100644
index 0000000000..3c29d646b5
--- /dev/null
+++ b/changelog/unreleased/pprof.md
@@ -0,0 +1,6 @@
+Enhancement: Add pprof http service
+
+This service is useful to trigger diagnostics 
+on running processes
+
+https://github.com/cs3org/reva/pull/4508
diff --git a/cmd/revad/runtime/http.go b/cmd/revad/runtime/http.go
index 1de255cdc1..9a919756c5 100644
--- a/cmd/revad/runtime/http.go
+++ b/cmd/revad/runtime/http.go
@@ -25,7 +25,6 @@ import (
 	"github.com/cs3org/reva/internal/http/interceptors/appctx"
 	"github.com/cs3org/reva/internal/http/interceptors/auth"
 	"github.com/cs3org/reva/internal/http/interceptors/log"
-	"github.com/cs3org/reva/internal/http/interceptors/metrics"
 	"github.com/cs3org/reva/internal/http/interceptors/trace"
 	"github.com/cs3org/reva/pkg/rhttp/global"
 	"github.com/pkg/errors"
@@ -72,7 +71,6 @@ func initHTTPMiddlewares(conf map[string]map[string]any, unprotected []string, l
 		authMiddle,
 		log.New(),
 		appctx.New(*logger),
-		metrics.New(),
 		trace.New(),
 	}
 
diff --git a/internal/http/services/loader/loader.go b/internal/http/services/loader/loader.go
index 405d8ff5df..d7d54f11e3 100644
--- a/internal/http/services/loader/loader.go
+++ b/internal/http/services/loader/loader.go
@@ -34,6 +34,7 @@ import (
 	_ "github.com/cs3org/reva/internal/http/services/owncloud/ocs"
 	_ "github.com/cs3org/reva/internal/http/services/pingpong"
 	_ "github.com/cs3org/reva/internal/http/services/plugins"
+	_ "github.com/cs3org/reva/internal/http/services/pprof"
 	_ "github.com/cs3org/reva/internal/http/services/preferences"
 	_ "github.com/cs3org/reva/internal/http/services/prometheus"
 	_ "github.com/cs3org/reva/internal/http/services/reverseproxy"
diff --git a/internal/http/services/pprof/pprof.go b/internal/http/services/pprof/pprof.go
new file mode 100644
index 0000000000..c0773e53c7
--- /dev/null
+++ b/internal/http/services/pprof/pprof.go
@@ -0,0 +1,80 @@
+// Copyright 2018-2024 CERN
+//
+// 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.
+//
+// In applying this license, CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+package pprof
+
+import (
+	"context"
+	"net/http"
+	"net/http/pprof"
+
+	"github.com/cs3org/reva/pkg/rhttp/global"
+	"github.com/cs3org/reva/pkg/utils/cfg"
+)
+
+func init() {
+	global.Register("pprof", New)
+}
+
+// New returns a new pprof service.
+func New(ctx context.Context, m map[string]interface{}) (global.Service, error) {
+	var c config
+	if err := cfg.Decode(m, &c); err != nil {
+		return nil, err
+	}
+
+	c.ApplyDefaults()
+
+	return &svc{conf: &c}, nil
+}
+
+// Close performs cleanup.
+func (s *svc) Close() error {
+	return nil
+}
+
+type config struct {
+	Prefix string `mapstructure:"prefix"`
+}
+
+func (c *config) ApplyDefaults() {
+	// pprof is always exposed at /debug
+	c.Prefix = "debug"
+}
+
+type svc struct {
+	conf *config
+}
+
+func (s *svc) Prefix() string {
+	return s.conf.Prefix
+}
+
+func (s *svc) Unprotected() []string {
+	return []string{"/"}
+}
+
+func (s *svc) Handler() http.Handler {
+	mux := http.NewServeMux()
+	// example: /debug/pprof/profile
+	mux.HandleFunc("/pprof/", pprof.Index)
+	mux.HandleFunc("/pprof/profile", pprof.Profile)
+	mux.HandleFunc("/pprof/symbol", pprof.Symbol)
+	mux.HandleFunc("/pprof/trace", pprof.Trace)
+	return mux
+}