add user and password to uri if the uri does not contain user password (#560)

* add user and password to uri if the uri does not contain user password

* improve compatibility

* extract whole `buildURI` logic and write a test

* add description for MONGODB_USER and MONGODB_PASSWORD in README.md

* fix for lint check

* make duplications test code simplified

* change properties order to make read easier

* add back mongodb:// append logic

* clean duplicate mongodb:// append logic

* try to fix lint

* move third party dependency below to internal dependency

Author: naughtyGitCat

README.md

@@ -71,14 +71,25 @@ Connecting user should have sufficient rights to query needed stats:
 More info about roles in MongoDB [documentation](https://docs.mongodb.com/manual/reference/built-in-roles/#mongodb-authrole-clusterMonitor).
 
 #### Example
-```
+```sh
 mongodb_exporter_linux_amd64/mongodb_exporter --mongodb.uri=mongodb://127.0.0.1:17001
 ```
 
+#### MongoDB Authentication
+You can supply the mongodb user/password direct in the `--mongodb.uri=` like `--mongodb.uri=mongodb://user:[email protected]:17001`, you can also supply the mongodb user/password with `--mongodb.user=`, `--mongodb.password=`
+but the user and password info will be leaked via `ps` or `top` command, for security issue, you can use `MONGODB_USER` and `MONGODB_PASSWORD` env variable to set user/password for given uri
+```sh
+MONGODB_USER=XXX MONGODB_PASSWORD=YYY mongodb_exporter_linux_amd64/mongodb_exporter --mongodb.uri=mongodb://127.0.0.1:17001 --mongodb.collstats-colls=db1.c1,db2.c2
+# or
+export MONGODB_USER=XXX
+export MONGODB_PASSWORD=YYY
+mongodb_exporter_linux_amd64/mongodb_exporter --mongodb.uri=mongodb://127.0.0.1:17001 --mongodb.collstats-colls=db1.c1,db2.c2
+```
+
 #### Enabling collstats metrics gathering
 `--mongodb.collstats-colls` receives a list of databases and collections to monitor using collstats.
 Usage example: `--mongodb.collstats-colls=database1.collection1,database2.collection2`
-```
+```sh
 mongodb_exporter_linux_amd64/mongodb_exporter --mongodb.uri=mongodb://127.0.0.1:17001 --mongodb.collstats-colls=db1.c1,db2.c2
 ```
 #### Enabling compatibility mode.

main.go

@@ -34,6 +34,8 @@ var (
 
 // GlobalFlags has command line flags to configure the exporter.
 type GlobalFlags struct {
+	User                  string `name:"mongodb.user" help:"monitor user, need clusterMonitor role in admin db and read role in local db" env:"MONGODB_USER" placeholder:"monitorUser"`
+	Password              string `name:"mongodb.password" help:"monitor user password" env:"MONGODB_PASSWORD" placeholder:"monitorPassword"`
 	CollStatsNamespaces   string `name:"mongodb.collstats-colls" help:"List of comma separared databases.collections to get $collStats" placeholder:"db1,db2.col2"`
 	IndexStatsCollections string `name:"mongodb.indexstats-colls" help:"List of comma separared databases.collections to get $indexStats" placeholder:"db1.col1,db2.col2"`
 	URI                   string `name:"mongodb.uri" help:"MongoDB connection URI" env:"MONGODB_URI" placeholder:"mongodb://user:[email protected]:27017/admin?ssl=true"`
@@ -89,6 +91,21 @@ func main() {
 	e.Run()
 }
 
+func buildURI(uri string, user string, password string) string {
+	// IF user@pass not contained in uri AND custom user and pass supplied in arguments
+	// DO concat a new uri with user and pass arguments value
+	if !strings.Contains(uri, "@") && user != "" && password != "" {
+		// trim mongodb:// prefix to handle user and pass logic
+		uri = strings.TrimPrefix(uri, "mongodb://")
+		// add user and pass to the uri
+		uri = fmt.Sprintf("%s:%s@%s", user, password, uri)
+	}
+	if !strings.HasPrefix(uri, "mongodb") {
+		uri = "mongodb://" + uri
+	}
+	return uri
+}
+
 func buildExporter(opts GlobalFlags) *exporter.Exporter {
 	log := logrus.New()
 
@@ -103,10 +120,7 @@ func buildExporter(opts GlobalFlags) *exporter.Exporter {
 
 	log.Debugf("Compatible mode: %v", opts.CompatibleMode)
 
-	if !strings.HasPrefix(opts.URI, "mongodb") {
-		log.Debugf("Prepending mongodb:// to the URI")
-		opts.URI = "mongodb://" + opts.URI
-	}
+	opts.URI = buildURI(opts.URI, opts.User, opts.Password)
 
 	log.Debugf("Connection URI: %s", opts.URI)
 

main_test.go

@@ -17,6 +17,8 @@ package main
 
 import (
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestBuildExporter(t *testing.T) {
@@ -37,3 +39,77 @@ func TestBuildExporter(t *testing.T) {
 
 	buildExporter(opts)
 }
+
+func TestBuildURI(t *testing.T) {
+	tests := []struct {
+		situation   string
+		origin      string
+		newUser     string
+		newPassword string
+		expect      string
+	}{
+		{
+			situation:   "uri with prefix and auth, and auth supplied in opt.User/Password",
+			origin:      "mongodb://usr:[email protected]",
+			newUser:     "xxx",
+			newPassword: "yyy",
+			expect:      "mongodb://usr:[email protected]",
+		},
+		{
+			situation:   "uri with prefix and auth, no auth supplied in opt.User/Password",
+			origin:      "mongodb://usr:[email protected]",
+			newUser:     "",
+			newPassword: "",
+			expect:      "mongodb://usr:[email protected]",
+		},
+		{
+			situation:   "uri with no prefix and auth, and auth supplied in opt.User/Password",
+			origin:      "usr:[email protected]",
+			newUser:     "xxx",
+			newPassword: "yyy",
+			expect:      "mongodb://usr:[email protected]",
+		},
+		{
+			situation:   "uri with no prefix and auth, no auth supplied in opt.User/Password",
+			origin:      "usr:[email protected]",
+			newUser:     "",
+			newPassword: "",
+			expect:      "mongodb://usr:[email protected]",
+		},
+		{
+			situation:   "uri with prefix and no auth, and auth supplied in opt.User/Password",
+			origin:      "mongodb://127.0.0.1",
+			newUser:     "xxx",
+			newPassword: "yyy",
+			expect:      "mongodb://xxx:[email protected]",
+		},
+		{
+			situation:   "uri with prefix and no auth, no auth supplied in opt.User/Password",
+			origin:      "mongodb://127.0.0.1",
+			newUser:     "",
+			newPassword: "",
+			expect:      "mongodb://127.0.0.1",
+		},
+		{
+			situation:   "uri with no prefix and no auth, and auth supplied in opt.User/Password",
+			origin:      "127.0.0.1",
+			newUser:     "xxx",
+			newPassword: "yyy",
+			expect:      "mongodb://xxx:[email protected]",
+		},
+		{
+			situation:   "uri with no prefix and no auth, no auth supplied in opt.User/Password",
+			origin:      "127.0.0.1",
+			newUser:     "",
+			newPassword: "",
+			expect:      "mongodb://127.0.0.1",
+		},
+	}
+	for _, tc := range tests {
+		newUri := buildURI(tc.origin, tc.newUser, tc.newPassword)
+		// t.Logf("Origin: %s", tc.origin)
+		// t.Logf("Expect: %s", tc.expect)
+		// t.Logf("Result: %s", newUri)
+		assert.Equal(t, newUri, tc.expect)
+	}
+}