docs: update changelog for release

Remove unnecessary name from the textfile import.
Remove the sqlite3 dependency which is no longer required.

.gitlab-ci.yml

@@ -1,21 +1,26 @@
 image: golang:latest
 
 before_script:
-  - make install-deps
+  - make go/dependencies
 
 stages:
   - test
   - build
 
+dependencies:
+  stage: test
+  script:
+    - make go/checkDependencies
+
 format:
   stage: test
   script:
-    - make format
+    - make go/checkFmt
 
 test:
   stage: test
   script:
-    - make test
+    - make go/test
 
 build:
   stage: build
@@ -31,7 +36,7 @@ build:
       - dist/checksums.txt
     expire_in: 1 day
 
-docker-gitlab:
+docker/gitlab:
   stage: build
   only:
     - main
@@ -44,6 +49,6 @@ docker-gitlab:
     - apk add make
     - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
   script:
-    - make docker/build-latest
-    - make docker/build-tag
+    - make docker/build/latest
+    - make docker/build/tag
     - docker push registry.gitlab.com/hectorjsmith/fail2ban-prometheus-exporter

.goreleaser.yml

@@ -2,13 +2,12 @@
 # Make sure to check the documentation at http://goreleaser.com
 before:
   hooks:
-    - make install-deps
+    - make go/dependencies
 builds:
   -
     dir: src
     goos:
       - linux
-      - windows
       - darwin
     goarch:
       - amd64

CHANGELOG.md

@@ -7,6 +7,17 @@ The format is based on [Keep a Changelog], and this project adheres to [Semantic
 ## [Unreleased]
 *Nothing yet*
 
+## [0.4.0] - 2021-10-18
+*Add new fail2ban config metrics*
+
+### Added
+- (56730c8) feat: add new jail config metrics
+- (5a107cc) feat: support for textfile metrics ([#13](https://gitlab.com/hectorjsmith/fail2ban-prometheus-exporter/issues/13))
+
+### Removed
+- (b268f86) remove: database-based metrics
+- (0b6a941) remove: windows builds
+
 ## [0.3.0] - 2021-09-27
 *Export new version metrics ([#12](https://gitlab.com/hectorjsmith/fail2ban-prometheus-exporter/issues/12))*
 
@@ -58,3 +69,4 @@ The format is based on [Keep a Changelog], and this project adheres to [Semantic
 [0.1.0]: https://gitlab.com/hectorjsmith/fail2ban-prometheus-exporter/compare/0.0.0...0.1.0
 [0.2.0]: https://gitlab.com/hectorjsmith/fail2ban-prometheus-exporter/compare/0.1.0...0.2.0
 [0.3.0]: https://gitlab.com/hectorjsmith/fail2ban-prometheus-exporter/compare/0.2.0...0.3.0
+[0.4.0]: https://gitlab.com/hectorjsmith/fail2ban-prometheus-exporter/compare/0.3.0...0.4.0

Makefile

@@ -1,20 +1,22 @@
-install-deps:
+go/dependencies:
 	cd src/ && go mod download
 
-# Standard go test
-test:
-	cd src/ && go test ./... -v -race
-
 # Make sure no unnecessary dependencies are present
-go-mod-tidy:
+go/checkDependencies:
 	cd src/ && go mod tidy -v
 	git diff-index --quiet HEAD
 
-format:
-	cd src/ && go fmt $(go list ./... | grep -v /vendor/)
-	cd src/ && go vet $(go list ./... | grep -v /vendor/)
+# Standard go test
+go/test:
+	cd src/ && go test ./... -v -race
 
-generateChangelog:
+go/fmt:
+	cd src/ && go fmt ./...
+
+go/checkFmt:
+	test -z $(shell gofmt -l .)
+
+docs/genChangelog:
 	./tools/git-chglog_linux_amd64 --config tools/chglog/config.yml 0.0.0.. > CHANGELOG_gen.md
 
 build/snapshot:
@@ -27,8 +29,8 @@ build/docker:
 	cd src/ && go build -o exporter \
      -ldflags '-X main.version=$(shell git describe --tags) -X main.commit=${shell git rev-parse HEAD} -X "main.date=${shell date --rfc-3339=seconds}" -X main.builtBy=docker' exporter.go
 
-docker/build-latest:
+docker/build/latest:
 	docker build -t registry.gitlab.com/hectorjsmith/fail2ban-prometheus-exporter:latest .
 
-docker/build-tag:
+docker/build/tag:
 	docker build -t registry.gitlab.com/hectorjsmith/fail2ban-prometheus-exporter:$(shell git describe --tags) .

README.md

@@ -15,21 +15,10 @@ Once the exporter is running, metrics are available at `localhost:9191/metrics`.
 
 (The default port is `9191` but can be modified with the `-port` flag)
 
-### 1.1. Socket
-The recommended way to run the exporter is to point it at the fail2ban server socket.
-This allows the exporter to communicate with the server the same way `fail2ban-client` does and ensures the metrics it collects align with the values reported by `fail2ban-client status <jail>`.
+The exporter communicates with the fail2ban server over its socket.
+This allows the data collected by the exporter to always align with the output of the `fail2ban-client`.
 
-The default path to the socket is: `/var/run/fail2ban/fail2ban.sock`
-
-### 1.2. Deprecated: Database
-The original way to collect metrics is to read them from the fail2ban database.
-This has now been deprecated in favour of using the socket.
-The reason being that database metrics do not always align with the output of `fail2ban-client status <jail>` and cause confusion.
-See [#11](https://gitlab.com/hectorjsmith/fail2ban-prometheus-exporter/-/issues/11) for more details.
-
-If necessary, these metrics can still be exported by providing the database path to the exporter.
-
-The default path to the fail2ban database is: `/var/lib/fail2ban/fail2ban.sqlite3`
+The default location of the socket is: `/var/run/fail2ban/fail2ban.sock`
 
 ## 2. Running the Exporter
 
@@ -44,14 +33,16 @@ See the [releases page](https://gitlab.com/hectorjsmith/fail2ban-prometheus-expo
 ```
 $ fail2ban-prometheus-exporter -h
 
-  -db string
-        path to the fail2ban sqlite database (deprecated)
   -port int
         port to use for the metrics server (default 9191)
   -socket string
         path to the fail2ban server socket
   -version
         show version info and exit
+  -collector.textfile
+        enable the textfile collector
+  -collector.textfile.directory string
+        directory to read text files with metrics from
 ```
 
 **Example**
@@ -60,7 +51,7 @@ $ fail2ban-prometheus-exporter -h
 fail2ban-prometheus-exporter -socket /var/run/fail2ban/fail2ban.sock -port 9191
 ```
 
-Note that the exporter will need read access to the fail2ban socket or database.
+Note that the exporter will need read access to the fail2ban socket.
 
 ### 2.1. Compile from Source
 
@@ -71,7 +62,7 @@ Run `go mod download` to download all necessary dependencies before running the
 
 ## 3. Running in Docker
 
-If use of docker is desired, an official docker image is available on the Gitlab container registry.
+An official docker image is available on the Gitlab container registry.
 Use it by pulling the following image:
 
 ```
@@ -83,11 +74,10 @@ See the [registry page](https://gitlab.com/hectorjsmith/fail2ban-prometheus-expo
 
 ### 3.1. Volumes
 
-The docker image is designed to run by mounting either the fail2ban sqlite3 database of the fail2ban run folder.
-- The database should be mounted at: `/app/fail2ban.sqlite3`
-- The run folder should be mounted at: `/var/run/fail2ban`
+The docker image is designed to run by mounting the fail2ban run folder.
+The run folder should be mounted in the container at: `/var/run/fail2ban`.
 
-Both paths can be mounted with readonly (`ro`) permissions.
+The folder can be mounted with read-only (`ro`) permissions.
 
 **NOTE:** While it is possible to mount the `fail2ban.sock` file directly, it is recommended to mount the parent folder instead.
 The `.sock` file is deleted by fail2ban on shutdown and re-created on startup and this causes problems for the docker mount.
@@ -100,7 +90,6 @@ Use the following command to run the exporter as a docker container.
 ```
 docker run -d \
     --name "fail2ban-exporter" \
-    -v /var/lib/fail2ban/fail2ban.sqlite3:/app/fail2ban.sqlite3:ro \
     -v /var/run/fail2ban:/var/run/fail2ban:ro \
     -p "9191:9191" \
     registry.gitlab.com/hectorjsmith/fail2ban-prometheus-exporter:latest
@@ -116,7 +105,6 @@ services:
   exporter:
     image: registry.gitlab.com/hectorjsmith/fail2ban-prometheus-exporter:latest
     volumes:
-    - /var/lib/fail2ban/fail2ban.sqlite3:/app/fail2ban.sqlite3:ro
     - /var/run/fail2ban/:/var/run/fail2ban:ro
     ports:
     - "9191:9191"
@@ -153,6 +141,10 @@ Exposed metrics:
 * `jail_banned_total` (per jail) - Total number of banned IPs since fail2ban startup (includes expired bans)
 * `jail_failed_current` (per jail) - Number of current failures
 * `jail_failed_total` (per jail) - Total number of failures since fail2ban startup
+* `jail_config_ban_time` (per jail) - How long an IP is banned for in this jail (in seconds)
+* `jail_config_find_time` (per jail) - How far back the filter will look for failures in this jail (in seconds)
+* `jail_config_max_retry` (per jail) - The max number of failures allowed before banning an IP in this jail
+* `version` - Version string of the exporter and fail2ban
 
 **Sample**
 
@@ -181,9 +173,24 @@ f2b_jail_failed_current{jail="sshd"} 6
 # TYPE f2b_jail_failed_total gauge
 f2b_jail_failed_total{jail="recidive"} 7
 f2b_jail_failed_total{jail="sshd"} 125
+# HELP f2b_config_jail_ban_time How long an IP is banned for in this jail (in seconds)
+# TYPE f2b_config_jail_ban_time gauge
+f2b_config_jail_ban_time{jail="recidive"} 604800
+f2b_config_jail_ban_time{jail="sshd"} 600
+# HELP f2b_config_jail_find_time How far back will the filter look for failures in this jail (in seconds)
+# TYPE f2b_config_jail_find_time gauge
+f2b_config_jail_find_time{jail="recidive"} 86400
+f2b_config_jail_find_time{jail="sshd"} 600
+# HELP f2b_config_jail_max_retries The number of failures allowed until the IP is banned by this jail
+# TYPE f2b_config_jail_max_retries gauge
+f2b_config_jail_max_retries{jail="recidive"} 5
+f2b_config_jail_max_retries{jail="sshd"} 5
 # HELP f2b_up Check if the fail2ban server is up
 # TYPE f2b_up gauge
 f2b_up 1
+# HELP f2b_version Version of the exporter and fail2ban server
+# TYPE f2b_version gauge
+f2b_version{exporter="0.3.0",fail2ban="0.11.1"} 1
 ```
 
 The metrics above correspond to the matching fields in the `fail2ban-client status <jail>` command:
@@ -198,45 +205,23 @@ Status for the jail: sshd|- Filter
    `- Banned IP list:   ...
 ```
 
-### 4.2. Database Metrics (deprecated)
+### 4.2. Textfile Metrics
 
-These are the original metrics exported by the initial release of the exporter.
-They are all based on the data stored in the fail2ban sqlite3 database.
+For more flexibility the exporter also allows exporting metrics collected from a text file.
 
-*These metrics are deprecated and will be removed in a future release.*
+To enable textfile metrics:
+1. Enable the collector with `-collector.textfile=true`
+2. Provide the directory to read files from with the `-collector.textfile.directory` flag
 
-All metrics are prefixed with `fail2ban_`.
+Metrics collected from these files will be exposed directly alongside the other metrics without any additional processing.
+This means that it is the responsibility of the file creator to ensure the format is correct.
 
-Exposed metrics:
-* `up` - Returns 1 if the service is up
-* `errors` - Returns the number of errors found since startup
-* `enabled_jails` - Returns 1 for each jail that is enabled, 0 if disabled.
-* `bad_ips` (per jail)
-    * A *bad IP* is defined as an IP that has been banned at least once in the past
-    * Bad IPs are counted per jail
-* `banned_ips` (per jail)
-    * A *banned IP* is defined as an IP that is currently banned on the firewall
-    * Banned IPs are counted per jail
-
-**Sample**
+By exporting textfile metrics an extra metric is also exported with an error count for each file:
 
 ```
-# HELP fail2ban_bad_ips (Deprecated) Number of bad IPs stored in the database (per jail).
-# TYPE fail2ban_bad_ips gauge
-fail2ban_bad_ips{jail="recidive"} 0
-fail2ban_bad_ips{jail="sshd"} 0
-# HELP fail2ban_banned_ips (Deprecated) Number of banned IPs stored in the database (per jail).
-# TYPE fail2ban_banned_ips gauge
-fail2ban_banned_ips{jail="recidive"} 0
-fail2ban_banned_ips{jail="sshd"} 0
-# HELP fail2ban_enabled_jails (Deprecated) Enabled jails.
-# TYPE fail2ban_enabled_jails gauge
-fail2ban_enabled_jails{jail="recidive"} 1
-fail2ban_enabled_jails{jail="sshd"} 1
-# HELP fail2ban_errors (Deprecated) Number of errors found since startup.
-# TYPE fail2ban_errors counter
-fail2ban_errors{type="db"} 0
-# HELP fail2ban_up (Deprecated) Was the last fail2ban query successful.
-# TYPE fail2ban_up gauge
-fail2ban_up 1
+# HELP textfile_error Checks for errors while reading text files
+# TYPE textfile_error gauge
+textfile_error{path="file.prom"} 0
 ```
+
+**NOTE:** Any file not ending with `.prom` will be ignored.

docker/run.sh

@@ -3,19 +3,18 @@
 # Print version to logs for debugging purposes
 /app/fail2ban-prometheus-exporter -version
 
-db_path=/app/fail2ban.sqlite3
 socket_path=/var/run/fail2ban/fail2ban.sock
+textfile_dir=/app/textfile/
+textfile_enabled=false
 
-# Blank out the file paths if they do not exist - a hacky way to only use these files if they were mounted into the container.
-if [ ! -f "$db_path" ]; then
-    db_path=""
-fi
-if [ ! -S "$socket_path" ]; then
-    socket_path=""
+# Enable textfile metrics if the folder exists (i.e. was mounted by docker)
+if [ -d $textfile_dir ]; then
+    textfile_enabled=true
 fi
 
 # Start the exporter (use exec to support graceful shutdown)
 # Inspired by: https://akomljen.com/stopping-docker-containers-gracefully/
 exec /app/fail2ban-prometheus-exporter \
-    -db "$db_path" \
-    -socket "$socket_path"
+    -socket "$socket_path" \
+    -collector.textfile=$textfile_enabled \
+    -collector.textfile.directory="$textfile_dir"

src/cfg/cfg.go

@@ -12,18 +12,23 @@ const (
 )
 
 type AppSettings struct {
-	VersionMode        bool
-	MetricsPort        int
-	Fail2BanDbPath     string
-	Fail2BanSocketPath string
+	VersionMode          bool
+	MetricsPort          int
+	Fail2BanSocketPath   string
+	FileCollectorPath    string
+	FileCollectorEnabled bool
 }
 
 func Parse() *AppSettings {
 	appSettings := &AppSettings{}
 	flag.BoolVar(&appSettings.VersionMode, "version", false, "show version info and exit")
 	flag.IntVar(&appSettings.MetricsPort, "port", 9191, "port to use for the metrics server")
-	flag.StringVar(&appSettings.Fail2BanDbPath, "db", "", "path to the fail2ban sqlite database (deprecated)")
 	flag.StringVar(&appSettings.Fail2BanSocketPath, "socket", "", "path to the fail2ban server socket")
+	flag.BoolVar(&appSettings.FileCollectorEnabled, "collector.textfile", false, "enable the textfile collector")
+	flag.StringVar(&appSettings.FileCollectorPath, "collector.textfile.directory", "", "directory to read text files with metrics from")
+
+	// deprecated: to be removed in next version
+	_ = flag.String("db", "", "path to the fail2ban sqlite database (removed)")
 
 	flag.Parse()
 	appSettings.validateFlags()
@@ -33,8 +38,8 @@ func Parse() *AppSettings {
 func (settings *AppSettings) validateFlags() {
 	var flagsValid = true
 	if !settings.VersionMode {
-		if settings.Fail2BanDbPath == "" && settings.Fail2BanSocketPath == "" {
-			fmt.Println("at least one of the following flags must be provided: 'db', 'socket'")
+		if settings.Fail2BanSocketPath == "" {
+			fmt.Println("fail2ban socket path must not be blank")
 			flagsValid = false
 		}
 		if settings.MetricsPort < minServerPort || settings.MetricsPort > maxServerPort {
@@ -42,6 +47,10 @@ func (settings *AppSettings) validateFlags() {
 				minServerPort, maxServerPort, settings.MetricsPort)
 			flagsValid = false
 		}
+		if settings.FileCollectorEnabled && settings.FileCollectorPath == "" {
+			fmt.Printf("file collector directory path must not be empty if collector enabled\n")
+			flagsValid = false
+		}
 	}
 	if !flagsValid {
 		flag.Usage()

src/collector/f2b/collector.go

@@ -0,0 +1,55 @@
+package f2b
+
+import (
+	"fail2ban-prometheus-exporter/cfg"
+	"fail2ban-prometheus-exporter/socket"
+	"github.com/prometheus/client_golang/prometheus"
+	"log"
+)
+
+type Collector struct {
+	socketPath                 string
+	exporterVersion            string
+	lastError                  error
+	dbErrorCount               int
+	socketConnectionErrorCount int
+	socketRequestErrorCount    int
+}
+
+func NewExporter(appSettings *cfg.AppSettings, exporterVersion string) *Collector {
+	return &Collector{
+		socketPath:                 appSettings.Fail2BanSocketPath,
+		exporterVersion:            exporterVersion,
+		lastError:                  nil,
+		dbErrorCount:               0,
+		socketConnectionErrorCount: 0,
+		socketRequestErrorCount:    0,
+	}
+}
+
+func (c *Collector) Describe(ch chan<- *prometheus.Desc) {
+	ch <- metricServerUp
+	ch <- metricJailCount
+	ch <- metricJailFailedCurrent
+	ch <- metricJailFailedTotal
+	ch <- metricJailBannedCurrent
+	ch <- metricJailBannedTotal
+	ch <- metricErrorCount
+}
+
+func (c *Collector) Collect(ch chan<- prometheus.Metric) {
+	s, err := socket.ConnectToSocket(c.socketPath)
+	if err != nil {
+		log.Printf("error opening socket: %v", err)
+		c.socketConnectionErrorCount++
+	} else {
+		defer s.Close()
+	}
+
+	c.collectServerUpMetric(ch, s)
+	if err == nil && s != nil {
+		c.collectJailMetrics(ch, s)
+		c.collectVersionMetric(ch, s)
+	}
+	c.collectErrorCountMetric(ch)
+}

src/collector/f2b/socket.go

@@ -1,4 +1,4 @@
-package export
+package f2b
 
 import (
 	"fail2ban-prometheus-exporter/socket"
@@ -46,6 +46,21 @@ var (
 		"Total number of IPs banned by this jail (includes expired bans)",
 		[]string{"jail"}, nil,
 	)
+	metricJailBanTime = prometheus.NewDesc(
+		prometheus.BuildFQName(namespace, "config", "jail_ban_time"),
+		"How long an IP is banned for in this jail (in seconds)",
+		[]string{"jail"}, nil,
+	)
+	metricJailFindTime = prometheus.NewDesc(
+		prometheus.BuildFQName(namespace, "config", "jail_find_time"),
+		"How far back will the filter look for failures in this jail (in seconds)",
+		[]string{"jail"}, nil,
+	)
+	metricJailMaxRetry = prometheus.NewDesc(
+		prometheus.BuildFQName(namespace, "config", "jail_max_retries"),
+		"The number of failures allowed until the IP is banned by this jail",
+		[]string{"jail"}, nil,
+	)
 	metricVersionInfo = prometheus.NewDesc(
 		prometheus.BuildFQName(namespace, "", "version"),
 		"Version of the exporter and fail2ban server",
@@ -53,24 +68,24 @@ var (
 	)
 )
 
-func (e *Exporter) collectErrorCountMetric(ch chan<- prometheus.Metric) {
+func (c *Collector) collectErrorCountMetric(ch chan<- prometheus.Metric) {
 	ch <- prometheus.MustNewConstMetric(
-		metricErrorCount, prometheus.CounterValue, float64(e.dbErrorCount), "db",
+		metricErrorCount, prometheus.CounterValue, float64(c.dbErrorCount), "db",
 	)
 	ch <- prometheus.MustNewConstMetric(
-		metricErrorCount, prometheus.CounterValue, float64(e.socketConnectionErrorCount), "socket_conn",
+		metricErrorCount, prometheus.CounterValue, float64(c.socketConnectionErrorCount), "socket_conn",
 	)
 	ch <- prometheus.MustNewConstMetric(
-		metricErrorCount, prometheus.CounterValue, float64(e.socketRequestErrorCount), "socket_req",
+		metricErrorCount, prometheus.CounterValue, float64(c.socketRequestErrorCount), "socket_req",
 	)
 }
 
-func (e *Exporter) collectServerUpMetric(ch chan<- prometheus.Metric, s *socket.Fail2BanSocket) {
+func (c *Collector) collectServerUpMetric(ch chan<- prometheus.Metric, s *socket.Fail2BanSocket) {
 	var serverUp float64 = 0
 	if s != nil {
 		pingSuccess, err := s.Ping()
 		if err != nil {
-			e.socketRequestErrorCount++
+			c.socketRequestErrorCount++
 			log.Print(err)
 		}
 		if err == nil && pingSuccess {
@@ -82,11 +97,11 @@ func (e *Exporter) collectServerUpMetric(ch chan<- prometheus.Metric, s *socket.
 	)
 }
 
-func (e *Exporter) collectJailMetrics(ch chan<- prometheus.Metric, s *socket.Fail2BanSocket) {
+func (c *Collector) collectJailMetrics(ch chan<- prometheus.Metric, s *socket.Fail2BanSocket) {
 	jails, err := s.GetJails()
 	var count float64 = 0
 	if err != nil {
-		e.socketRequestErrorCount++
+		c.socketRequestErrorCount++
 		log.Print(err)
 	}
 	if err == nil {
@@ -97,14 +112,15 @@ func (e *Exporter) collectJailMetrics(ch chan<- prometheus.Metric, s *socket.Fai
 	)
 
 	for i := range jails {
-		e.collectJailStatsMetric(ch, s, jails[i])
+		c.collectJailStatsMetric(ch, s, jails[i])
+		c.collectJailConfigMetrics(ch, s, jails[i])
 	}
 }
 
-func (e *Exporter) collectJailStatsMetric(ch chan<- prometheus.Metric, s *socket.Fail2BanSocket, jail string) {
+func (c *Collector) collectJailStatsMetric(ch chan<- prometheus.Metric, s *socket.Fail2BanSocket, jail string) {
 	stats, err := s.GetJailStats(jail)
 	if err != nil {
-		e.socketRequestErrorCount++
+		c.socketRequestErrorCount++
 		log.Printf("failed to get stats for jail %s: %v", jail, err)
 		return
 	}
@@ -123,18 +139,44 @@ func (e *Exporter) collectJailStatsMetric(ch chan<- prometheus.Metric, s *socket
 	)
 }
 
-func (e *Exporter) collectVersionMetric(ch chan<- prometheus.Metric, s *socket.Fail2BanSocket) {
-	var err error
-	var fail2banVersion = ""
-	if s != nil {
-		fail2banVersion, err = s.GetServerVersion()
-		if err != nil {
-			e.socketRequestErrorCount++
-			log.Printf("failed to get fail2ban server version: %v", err)
-		}
+func (c *Collector) collectJailConfigMetrics(ch chan<- prometheus.Metric, s *socket.Fail2BanSocket, jail string) {
+	banTime, err := s.GetJailBanTime(jail)
+	if err != nil {
+		c.socketRequestErrorCount++
+		log.Printf("failed to get ban time for jail %s: %v", jail, err)
+	} else {
+		ch <- prometheus.MustNewConstMetric(
+			metricJailBanTime, prometheus.GaugeValue, float64(banTime), jail,
+		)
+	}
+	findTime, err := s.GetJailFindTime(jail)
+	if err != nil {
+		c.socketRequestErrorCount++
+		log.Printf("failed to get find time for jail %s: %v", jail, err)
+	} else {
+		ch <- prometheus.MustNewConstMetric(
+			metricJailFindTime, prometheus.GaugeValue, float64(findTime), jail,
+		)
+	}
+	maxRetry, err := s.GetJailMaxRetries(jail)
+	if err != nil {
+		c.socketRequestErrorCount++
+		log.Printf("failed to get max retries for jail %s: %v", jail, err)
+	} else {
+		ch <- prometheus.MustNewConstMetric(
+			metricJailMaxRetry, prometheus.GaugeValue, float64(maxRetry), jail,
+		)
+	}
+}
+
+func (c *Collector) collectVersionMetric(ch chan<- prometheus.Metric, s *socket.Fail2BanSocket) {
+	fail2banVersion, err := s.GetServerVersion()
+	if err != nil {
+		c.socketRequestErrorCount++
+		log.Printf("failed to get fail2ban server version: %v", err)
 	}
 
 	ch <- prometheus.MustNewConstMetric(
-		metricVersionInfo, prometheus.GaugeValue, float64(1), e.exporterVersion, fail2banVersion,
+		metricVersionInfo, prometheus.GaugeValue, float64(1), c.exporterVersion, fail2banVersion,
 	)
 }

src/collector/textfile/collector.go

@@ -0,0 +1,48 @@
+package textfile
+
+import (
+	"fail2ban-prometheus-exporter/cfg"
+	"github.com/prometheus/client_golang/prometheus"
+	"log"
+)
+
+type Collector struct {
+	enabled    bool
+	folderPath string
+	fileMap    map[string]*fileData
+}
+
+type fileData struct {
+	readErrors   int
+	fileName     string
+	fileContents []byte
+}
+
+func NewCollector(appSettings *cfg.AppSettings) *Collector {
+	collector := &Collector{
+		enabled:    appSettings.FileCollectorEnabled,
+		folderPath: appSettings.FileCollectorPath,
+		fileMap:    make(map[string]*fileData),
+	}
+	if collector.enabled {
+		log.Printf("collector.textfile directory: %s", collector.folderPath)
+	}
+	return collector
+}
+
+func (c *Collector) Describe(ch chan<- *prometheus.Desc) {
+	if c.enabled {
+		ch <- metricReadError
+	}
+}
+
+func (c *Collector) Collect(ch chan<- prometheus.Metric) {
+	if c.enabled {
+		c.collectFileContents()
+		c.collectFileErrors(ch)
+	}
+}
+
+func (c *Collector) appendErrorForPath(path string) {
+	c.fileMap[path].readErrors++
+}

src/collector/textfile/file.go

@@ -0,0 +1,55 @@
+package textfile
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"io/ioutil"
+	"log"
+	"path/filepath"
+	"strings"
+)
+
+const namespace = "textfile"
+
+var (
+	metricReadError = prometheus.NewDesc(
+		prometheus.BuildFQName(namespace, "", "error"),
+		"Checks for errors while reading text files",
+		[]string{"path"}, nil,
+	)
+)
+
+func (c *Collector) collectFileContents() {
+	files, err := ioutil.ReadDir(c.folderPath)
+	if err != nil {
+		log.Printf("error reading directory '%s': %v", c.folderPath, err)
+		return
+	}
+
+	for _, file := range files {
+		fileName := file.Name()
+		if !strings.HasSuffix(strings.ToLower(fileName), ".prom") {
+			continue
+		}
+		c.fileMap[fileName] = &fileData{
+			readErrors: 0,
+			fileName:   fileName,
+		}
+
+		fullPath := filepath.Join(c.folderPath, fileName)
+		content, err := ioutil.ReadFile(fullPath)
+		if err != nil {
+			c.appendErrorForPath(fileName)
+			log.Printf("error reading contents of file '%s': %v", fileName, err)
+		}
+
+		c.fileMap[fileName].fileContents = content
+	}
+}
+
+func (c *Collector) collectFileErrors(ch chan<- prometheus.Metric) {
+	for _, f := range c.fileMap {
+		ch <- prometheus.MustNewConstMetric(
+			metricReadError, prometheus.GaugeValue, float64(f.readErrors), f.fileName,
+		)
+	}
+}

src/collector/textfile/writer.go

@@ -0,0 +1,20 @@
+package textfile
+
+import (
+	"log"
+	"net/http"
+)
+
+func (c *Collector) WriteTextFileMetrics(w http.ResponseWriter, r *http.Request) {
+	if !c.enabled {
+		return
+	}
+
+	for _, f := range c.fileMap {
+		_, err := w.Write(f.fileContents)
+		if err != nil {
+			c.appendErrorForPath(f.fileName)
+			log.Printf("error writing file contents to response writer '%s': %v", f.fileName, err)
+		}
+	}
+}

src/db/db.go

@@ -1,84 +0,0 @@
-package db
-
-import (
-	"database/sql"
-	"log"
-	"os"
-)
-
-const queryBadIpsPerJail = "SELECT j.name, (SELECT COUNT(1) FROM bips b WHERE j.name = b.jail) FROM jails j"
-const queryBannedIpsPerJail = "SELECT j.name, (SELECT COUNT(1) FROM bans b WHERE j.name = b.jail AND b.timeofban + b.bantime >= strftime('%s','now') + 0) FROM jails j"
-const queryJailNameToEnabled = "SELECT j.name, j.enabled FROM jails j"
-
-type Fail2BanDB struct {
-	DatabasePath string
-	sqliteDB     *sql.DB
-}
-
-func MustConnectToDb(databasePath string) *Fail2BanDB {
-	if _, err := os.Stat(databasePath); os.IsNotExist(err) {
-		log.Fatalf("database path does not exist: %v", err)
-	}
-	db, err := sql.Open("sqlite3", databasePath)
-	if err != nil {
-		log.Fatal(err)
-	}
-	return &Fail2BanDB{
-		DatabasePath: databasePath,
-		sqliteDB:     db,
-	}
-}
-
-func (db *Fail2BanDB) CountBannedIpsPerJail() (map[string]int, error) {
-	return db.RunJailNameToCountQuery(queryBannedIpsPerJail)
-}
-
-func (db *Fail2BanDB) CountBadIpsPerJail() (map[string]int, error) {
-	return db.RunJailNameToCountQuery(queryBadIpsPerJail)
-}
-
-func (db *Fail2BanDB) JailNameToEnabledValue() (map[string]int, error) {
-	return db.RunJailNameToCountQuery(queryJailNameToEnabled)
-}
-
-func (db *Fail2BanDB) RunJailNameToCountQuery(query string) (map[string]int, error) {
-	stmt, err := db.sqliteDB.Prepare(query)
-	defer db.mustCloseStatement(stmt)
-
-	if err != nil {
-		return nil, err
-	}
-
-	jailNameToCountMap := map[string]int{}
-	rows, err := stmt.Query()
-	if err != nil {
-		return nil, err
-	}
-	if rows == nil {
-		return jailNameToCountMap, nil
-	}
-
-	for rows.Next() {
-		if rows.Err() != nil {
-			return nil, err
-		}
-		jailName := ""
-		count := 0
-		err = rows.Scan(&jailName, &count)
-		if err != nil {
-			return nil, err
-		}
-
-		jailNameToCountMap[jailName] = count
-	}
-	return jailNameToCountMap, nil
-}
-
-func (db *Fail2BanDB) mustCloseStatement(stmt *sql.Stmt) {
-	if stmt != nil {
-		err := stmt.Close()
-		if err != nil {
-			log.Fatal(err)
-		}
-	}
-}

src/export/build.go

@@ -1,25 +0,0 @@
-package export
-
-import (
-	"fail2ban-prometheus-exporter/cfg"
-	fail2banDb "fail2ban-prometheus-exporter/db"
-	"log"
-)
-
-func NewExporter(appSettings *cfg.AppSettings, exporterVersion string) *Exporter {
-	exporter := &Exporter{
-		exporterVersion:            exporterVersion,
-		lastError:                  nil,
-		dbErrorCount:               0,
-		socketConnectionErrorCount: 0,
-		socketRequestErrorCount:    0,
-	}
-	if appSettings.Fail2BanDbPath != "" {
-		log.Print("database-based metrics have been deprecated and will be removed in a future release")
-		exporter.db = fail2banDb.MustConnectToDb(appSettings.Fail2BanDbPath)
-	}
-	if appSettings.Fail2BanSocketPath != "" {
-		exporter.socketPath = appSettings.Fail2BanSocketPath
-	}
-	return exporter
-}

src/export/database.go

@@ -1,102 +0,0 @@
-package export
-
-import (
-	"github.com/prometheus/client_golang/prometheus"
-	"log"
-)
-
-const (
-	deprecatedNamespace = "fail2ban"
-)
-
-var (
-	deprecatedMetricUp = prometheus.NewDesc(
-		prometheus.BuildFQName(deprecatedNamespace, "", "up"),
-		"(Deprecated) Was the last fail2ban query successful.",
-		nil, nil,
-	)
-	deprecatedMetricBannedIpsPerJail = prometheus.NewDesc(
-		prometheus.BuildFQName(deprecatedNamespace, "", "banned_ips"),
-		"(Deprecated) Number of banned IPs stored in the database (per jail).",
-		[]string{"jail"}, nil,
-	)
-	deprecatedMetricBadIpsPerJail = prometheus.NewDesc(
-		prometheus.BuildFQName(deprecatedNamespace, "", "bad_ips"),
-		"(Deprecated) Number of bad IPs stored in the database (per jail).",
-		[]string{"jail"}, nil,
-	)
-	deprecatedMetricEnabledJails = prometheus.NewDesc(
-		prometheus.BuildFQName(deprecatedNamespace, "", "enabled_jails"),
-		"(Deprecated) Enabled jails.",
-		[]string{"jail"}, nil,
-	)
-	deprecatedMetricErrorCount = prometheus.NewDesc(
-		prometheus.BuildFQName(deprecatedNamespace, "", "errors"),
-		"(Deprecated) Number of errors found since startup.",
-		[]string{"type"}, nil,
-	)
-)
-
-func (e *Exporter) collectDeprecatedUpMetric(ch chan<- prometheus.Metric) {
-	var upMetricValue float64 = 1
-	if e.lastError != nil {
-		upMetricValue = 0
-	}
-	ch <- prometheus.MustNewConstMetric(
-		deprecatedMetricUp, prometheus.GaugeValue, upMetricValue,
-	)
-}
-
-func (e *Exporter) collectDeprecatedErrorCountMetric(ch chan<- prometheus.Metric) {
-	ch <- prometheus.MustNewConstMetric(
-		deprecatedMetricErrorCount, prometheus.CounterValue, float64(e.dbErrorCount), "db",
-	)
-}
-
-func (e *Exporter) collectDeprecatedBadIpsPerJailMetrics(ch chan<- prometheus.Metric) {
-	jailNameToCountMap, err := e.db.CountBadIpsPerJail()
-	e.lastError = err
-
-	if err != nil {
-		e.dbErrorCount++
-		log.Print(err)
-	}
-
-	for jailName, count := range jailNameToCountMap {
-		ch <- prometheus.MustNewConstMetric(
-			deprecatedMetricBadIpsPerJail, prometheus.GaugeValue, float64(count), jailName,
-		)
-	}
-}
-
-func (e *Exporter) collectDeprecatedBannedIpsPerJailMetrics(ch chan<- prometheus.Metric) {
-	jailNameToCountMap, err := e.db.CountBannedIpsPerJail()
-	e.lastError = err
-
-	if err != nil {
-		e.dbErrorCount++
-		log.Print(err)
-	}
-
-	for jailName, count := range jailNameToCountMap {
-		ch <- prometheus.MustNewConstMetric(
-			deprecatedMetricBannedIpsPerJail, prometheus.GaugeValue, float64(count), jailName,
-		)
-	}
-}
-
-func (e *Exporter) collectDeprecatedEnabledJailMetrics(ch chan<- prometheus.Metric) {
-	jailNameToEnabledMap, err := e.db.JailNameToEnabledValue()
-	e.lastError = err
-
-	if err != nil {
-		e.dbErrorCount++
-		log.Print(err)
-	}
-
-	for jailName, count := range jailNameToEnabledMap {
-		ch <- prometheus.MustNewConstMetric(
-			deprecatedMetricEnabledJails, prometheus.GaugeValue, float64(count), jailName,
-		)
-	}
-}

src/export/exporter.go

@@ -1,64 +0,0 @@
-package export
-
-import (
-	fail2banDb "fail2ban-prometheus-exporter/db"
-	"fail2ban-prometheus-exporter/socket"
-	"github.com/prometheus/client_golang/prometheus"
-	"log"
-)
-
-type Exporter struct {
-	db                         *fail2banDb.Fail2BanDB
-	socketPath                 string
-	exporterVersion            string
-	lastError                  error
-	dbErrorCount               int
-	socketConnectionErrorCount int
-	socketRequestErrorCount    int
-}
-
-func (e *Exporter) Describe(ch chan<- *prometheus.Desc) {
-	if e.db != nil {
-		ch <- deprecatedMetricUp
-		ch <- deprecatedMetricBadIpsPerJail
-		ch <- deprecatedMetricBannedIpsPerJail
-		ch <- deprecatedMetricEnabledJails
-		ch <- deprecatedMetricErrorCount
-	}
-	if e.socketPath != "" {
-		ch <- metricServerUp
-		ch <- metricJailCount
-		ch <- metricJailFailedCurrent
-		ch <- metricJailFailedTotal
-		ch <- metricJailBannedCurrent
-		ch <- metricJailBannedTotal
-	}
-	ch <- metricErrorCount
-}
-
-func (e *Exporter) Collect(ch chan<- prometheus.Metric) {
-	if e.db != nil {
-		e.collectDeprecatedBadIpsPerJailMetrics(ch)
-		e.collectDeprecatedBannedIpsPerJailMetrics(ch)
-		e.collectDeprecatedEnabledJailMetrics(ch)
-		e.collectDeprecatedUpMetric(ch)
-		e.collectDeprecatedErrorCountMetric(ch)
-	}
-	if e.socketPath != "" {
-		s, err := socket.ConnectToSocket(e.socketPath)
-		if err != nil {
-			log.Printf("error opening socket: %v", err)
-			e.socketConnectionErrorCount++
-		} else {
-			defer s.Close()
-		}
-		e.collectServerUpMetric(ch, s)
-		if err == nil && s != nil {
-			e.collectJailMetrics(ch, s)
-		}
-		e.collectVersionMetric(ch, s)
-	} else {
-		e.collectVersionMetric(ch, nil)
-	}
-	e.collectErrorCountMetric(ch)
-}

src/exporter.go

@@ -2,12 +2,12 @@ package main
 
 import (
 	"fail2ban-prometheus-exporter/cfg"
-	"fail2ban-prometheus-exporter/export"
+	"fail2ban-prometheus-exporter/collector/f2b"
+	"fail2ban-prometheus-exporter/collector/textfile"
 	"fmt"
 	"log"
 	"net/http"
 
-	_ "github.com/mattn/go-sqlite3"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
@@ -43,6 +43,11 @@ func rootHtmlHandler(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
+func metricHandler(w http.ResponseWriter, r *http.Request, collector *textfile.Collector) {
+	promhttp.Handler().ServeHTTP(w, r)
+	collector.WriteTextFileMetrics(w, r)
+}
+
 func main() {
 	appSettings := cfg.Parse()
 	if appSettings.VersionMode {
@@ -52,11 +57,16 @@ func main() {
 
 		log.Printf("starting fail2ban exporter at %s", addr)
 
-		exporter := export.NewExporter(appSettings, version)
-		prometheus.MustRegister(exporter)
+		f2bCollector := f2b.NewExporter(appSettings, version)
+		prometheus.MustRegister(f2bCollector)
+
+		textFileCollector := textfile.NewCollector(appSettings)
+		prometheus.MustRegister(textFileCollector)
 
 		http.HandleFunc("/", rootHtmlHandler)
-		http.Handle(metricsPath, promhttp.Handler())
+		http.HandleFunc(metricsPath, func(w http.ResponseWriter, r *http.Request) {
+			metricHandler(w, r, textFileCollector)
+		})
 		log.Printf("metrics available at '%s'", metricsPath)
 
 		svrErr := make(chan error)

src/go.mod

@@ -4,7 +4,6 @@ go 1.15
 
 require (
 	github.com/kisielk/og-rek v1.1.0
-	github.com/mattn/go-sqlite3 v1.14.6
 	github.com/nlpodyssey/gopickle v0.1.0
 	github.com/prometheus/client_golang v1.9.0
 )

src/go.sum

@@ -152,8 +152,6 @@ github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaO
 github.com/mattn/go-isatty v0.0.3/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNxMWT7Zi4=
 github.com/mattn/go-isatty v0.0.4/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNxMWT7Zi4=
 github.com/mattn/go-runewidth v0.0.2/go.mod h1:LwmH8dsx7+W8Uxz3IHJYH5QSwggIsqBzpuz5H//U1FU=
-github.com/mattn/go-sqlite3 v1.14.6 h1:dNPt6NO46WmLVt2DLNpwczCmdV5boIZ6g/tlDrlRUbg=
-github.com/mattn/go-sqlite3 v1.14.6/go.mod h1:NyWgC/yNuGj7Q9rpYnZvas74GogHl5/Z4A/KQRfk6bU=
 github.com/matttproud/golang_protobuf_extensions v1.0.1 h1:4hp9jkHxhMHkqkrB3Ix0jegS5sx/RkqARlsWZ6pIwiU=
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
 github.com/miekg/dns v1.0.14/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=

src/socket/fail2banSocket.go

@@ -118,6 +118,21 @@ func (s *Fail2BanSocket) GetJailStats(jail string) (JailStats, error) {
 	return stats, newBadFormatError(statusCommand, response)
 }
 
+func (s *Fail2BanSocket) GetJailBanTime(jail string) (int, error) {
+	command := fmt.Sprintf(banTimeCommandFmt, jail)
+	return s.sendSimpleIntCommand(command)
+}
+
+func (s *Fail2BanSocket) GetJailFindTime(jail string) (int, error) {
+	command := fmt.Sprintf(findTimeCommandFmt, jail)
+	return s.sendSimpleIntCommand(command)
+}
+
+func (s *Fail2BanSocket) GetJailMaxRetries(jail string) (int, error) {
+	command := fmt.Sprintf(maxRetriesCommandFmt, jail)
+	return s.sendSimpleIntCommand(command)
+}
+
 func (s *Fail2BanSocket) GetServerVersion() (string, error) {
 	response, err := s.sendCommand([]string{versionCommand})
 	if err != nil {
@@ -132,6 +147,22 @@ func (s *Fail2BanSocket) GetServerVersion() (string, error) {
 	return "", newBadFormatError(versionCommand, response)
 }
 
+// sendSimpleIntCommand sends a command to the fail2ban socket and parses the response to extract an int.
+// This command assumes that the response data is in the format of `(d, d)` where `d` is a number.
+func (s *Fail2BanSocket) sendSimpleIntCommand(command string) (int, error) {
+	response, err := s.sendCommand(strings.Split(command, " "))
+	if err != nil {
+		return -1, err
+	}
+
+	if lvl1, ok := response.(*types.Tuple); ok {
+		if banTime, ok := lvl1.Get(1).(int); ok {
+			return banTime, nil
+		}
+	}
+	return -1, newBadFormatError(command, response)
+}
+
 func newBadFormatError(command string, data interface{}) error {
 	return fmt.Errorf("(%s) unexpected response format - cannot parse: %v", command, data)
 }

src/socket/protocol.go

@@ -12,6 +12,9 @@ const (
 	pingCommand          = "ping"
 	statusCommand        = "status"
 	versionCommand       = "version"
+	banTimeCommandFmt    = "get %s bantime"
+	findTimeCommandFmt   = "get %s findtime"
+	maxRetriesCommandFmt = "get %s maxretry"
 	socketReadBufferSize = 1024
 )