fail2ban-prometheus-exporter/src/exporter.go

package main

import (
	"fail2ban-prometheus-exporter/cfg"
	"fail2ban-prometheus-exporter/export"
	"fail2ban-prometheus-exporter/textfile"
	"fmt"
	"log"
	"net/http"

	_ "github.com/mattn/go-sqlite3"
	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/promhttp"
)

const (
	metricsPath = "/metrics"
)

var (
	version = "dev"
	commit  = "none"
	date    = "unknown"
	builtBy = "unknown"
)

func printAppVersion() {
	fmt.Println(version)
	fmt.Printf("    build date:  %s\r\n    commit hash: %s\r\n    built by:    %s\r\n", date, commit, builtBy)
}

func rootHtmlHandler(w http.ResponseWriter, r *http.Request) {
	_, err := w.Write([]byte(
		`<html>
			<head><title>Fail2Ban Exporter</title></head>
			<body>
			<h1>Fail2Ban Exporter</h1>
			<p><a href="` + metricsPath + `">Metrics</a></p>
			</body>
		</html>`))
	if err != nil {
		log.Printf("error handling root url: %v", err)
		w.WriteHeader(http.StatusInternalServerError)
	}
}

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 {
		printAppVersion()
	} else {
		addr := fmt.Sprintf("0.0.0.0:%d", appSettings.MetricsPort)

		log.Printf("starting fail2ban exporter at %s", addr)

		exporter := export.NewExporter(appSettings, version)
		prometheus.MustRegister(exporter)

		textFileCollector := textfile.NewCollector(appSettings)
		prometheus.MustRegister(textFileCollector)

		http.HandleFunc("/", rootHtmlHandler)
		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)
		go func() {
			svrErr <- http.ListenAndServe(addr, nil)
		}()
		log.Print("ready")

		err := <-svrErr
		log.Print(err)
	}
}
initial commit 2021-02-05 23:49:47 +01:00			`package main`

feat: initial setup of metric exporter Add dependency on the prometheus library to start exporting metrics. Add a new `up` metric that always returns `1` to ensure the exporter is working as expected. 2021-02-06 00:01:00 +01:00			`import (`
feat: add cli parameters for db path and metrics port (#4) Add support for configuring CLI parameters in the application using a new `cfg` package. The `cfg` package exports an `AppSettings` struct that contains the settings the application was run with. Update the application to use the new CLI parameters to set the db to open and the port to use for the metrics server. Add support for setting the app version during build. The app includes a `-version` flag to print the stored version data. 2021-02-06 16:17:35 +01:00			`"fail2ban-prometheus-exporter/cfg"`
refactor: move exporter code to new package Split out all the code to define exporter functions and collect data into a new package. The new package is responsible for all exporter related activity. This makes the code easier to read. Split the code for collecting metrics from the database and from the socket into different files to make the separation more obvious. 2021-09-13 21:25:54 +02:00			`"fail2ban-prometheus-exporter/export"`
feat: support for textfile metrics (#13) Add support for collecting arbitrary metrics from a textfile as well as metrics collected from fail2ban. This allows other data to be exported along with the fail2ban metrics (e.g. instance metadata). Update the docker image to allow mounting a folder with a collection of metric files to be exported. Only files ending in `.prom` with be read. Update project README with the new functionality. 2021-10-12 22:38:26 +02:00			`"fail2ban-prometheus-exporter/textfile"`
feat: add cli parameters for db path and metrics port (#4) Add support for configuring CLI parameters in the application using a new `cfg` package. The `cfg` package exports an `AppSettings` struct that contains the settings the application was run with. Update the application to use the new CLI parameters to set the db to open and the port to use for the metrics server. Add support for setting the app version during build. The app includes a `-version` flag to print the stored version data. 2021-02-06 16:17:35 +01:00			`"fmt"`
feat: collect new up metric from fail2ban socket Add support for connecting the exporter directly to the fail2ban server's socket to send requests and receive data. The path to the socket file is optional and specified on startup. Export a new metric based on the response of the `ping` command sent to the fail2ban server. The metric is set to 1 if the server responds with `pong` and 0 in any other case. This metric is only shown if the path to the socket file was provided on startup. 2021-08-29 13:50:53 +02:00			`"log"`
			`"net/http"`

feat: connect to fail2ban db and extract total bad ips Add dependencies on `sqlite` to allow connecting to the fail2ban database. Add a new `db` module to handle all the database connections and data queries used to generate metrics. Export a new metric for the total number of bad IPs stored in the fail2ban database. 2021-02-06 12:45:46 +01:00			`_ "github.com/mattn/go-sqlite3"`
feat: initial setup of metric exporter Add dependency on the prometheus library to start exporting metrics. Add a new `up` metric that always returns `1` to ensure the exporter is working as expected. 2021-02-06 00:01:00 +01:00			`"github.com/prometheus/client_golang/prometheus"`
			`"github.com/prometheus/client_golang/prometheus/promhttp"`
			`)`

feat: improve startup logging Update the exporter startup to add more log messages. The server address, port, and metrics path are now logged on startup. A "ready" log message is printed when the server is up and running. 2021-09-21 10:34:23 +02:00			`const (`
			`metricsPath = "/metrics"`
			`)`

feat: connect to fail2ban db and extract total bad ips Add dependencies on `sqlite` to allow connecting to the fail2ban database. Add a new `db` module to handle all the database connections and data queries used to generate metrics. Export a new metric for the total number of bad IPs stored in the fail2ban database. 2021-02-06 12:45:46 +01:00			`var (`
feat: add cli parameters for db path and metrics port (#4) Add support for configuring CLI parameters in the application using a new `cfg` package. The `cfg` package exports an `AppSettings` struct that contains the settings the application was run with. Update the application to use the new CLI parameters to set the db to open and the port to use for the metrics server. Add support for setting the app version during build. The app includes a `-version` flag to print the stored version data. 2021-02-06 16:17:35 +01:00			`version = "dev"`
			`commit = "none"`
			`date = "unknown"`
			`builtBy = "unknown"`
feat: initial setup of metric exporter Add dependency on the prometheus library to start exporting metrics. Add a new `up` metric that always returns `1` to ensure the exporter is working as expected. 2021-02-06 00:01:00 +01:00			`)`

feat: add cli parameters for db path and metrics port (#4) Add support for configuring CLI parameters in the application using a new `cfg` package. The `cfg` package exports an `AppSettings` struct that contains the settings the application was run with. Update the application to use the new CLI parameters to set the db to open and the port to use for the metrics server. Add support for setting the app version during build. The app includes a `-version` flag to print the stored version data. 2021-02-06 16:17:35 +01:00			`func printAppVersion() {`
			`fmt.Println(version)`
			`fmt.Printf(" build date: %s\r\n commit hash: %s\r\n built by: %s\r\n", date, commit, builtBy)`
			`}`

feat: render basic html page at root url Add a new request handler for the root URL (`/`) to render a simple HTML page with a link to the metrics page. This follows the convention of other metric exporters. 2021-09-25 23:23:28 +02:00			`func rootHtmlHandler(w http.ResponseWriter, r *http.Request) {`
			`_, err := w.Write([]byte(`
			`<html>
			`<head><title>Fail2Ban Exporter</title></head>`
			`<body>`
			`<h1>Fail2Ban Exporter</h1>`
			<p><a href="` + metricsPath + `">Metrics</a></p>
			`</body>`
			</html>`))
			`if err != nil {`
			`log.Printf("error handling root url: %v", err)`
			`w.WriteHeader(http.StatusInternalServerError)`
			`}`
			`}`

feat: support for textfile metrics (#13) Add support for collecting arbitrary metrics from a textfile as well as metrics collected from fail2ban. This allows other data to be exported along with the fail2ban metrics (e.g. instance metadata). Update the docker image to allow mounting a folder with a collection of metric files to be exported. Only files ending in `.prom` with be read. Update project README with the new functionality. 2021-10-12 22:38:26 +02:00			`func metricHandler(w http.ResponseWriter, r http.Request, collector textfile.Collector) {`
			`promhttp.Handler().ServeHTTP(w, r)`
			`collector.WriteTextFileMetrics(w, r)`
			`}`

initial commit 2021-02-05 23:49:47 +01:00			`func main() {`
feat: add cli parameters for db path and metrics port (#4) Add support for configuring CLI parameters in the application using a new `cfg` package. The `cfg` package exports an `AppSettings` struct that contains the settings the application was run with. Update the application to use the new CLI parameters to set the db to open and the port to use for the metrics server. Add support for setting the app version during build. The app includes a `-version` flag to print the stored version data. 2021-02-06 16:17:35 +01:00			`appSettings := cfg.Parse()`
			`if appSettings.VersionMode {`
			`printAppVersion()`
			`} else {`
feat: improve startup logging Update the exporter startup to add more log messages. The server address, port, and metrics path are now logged on startup. A "ready" log message is printed when the server is up and running. 2021-09-21 10:34:23 +02:00			`addr := fmt.Sprintf("0.0.0.0:%d", appSettings.MetricsPort)`

			`log.Printf("starting fail2ban exporter at %s", addr)`
feat: initial setup of metric exporter Add dependency on the prometheus library to start exporting metrics. Add a new `up` metric that always returns `1` to ensure the exporter is working as expected. 2021-02-06 00:01:00 +01:00
refactor: move exporter code to new package Split out all the code to define exporter functions and collect data into a new package. The new package is responsible for all exporter related activity. This makes the code easier to read. Split the code for collecting metrics from the database and from the socket into different files to make the separation more obvious. 2021-09-13 21:25:54 +02:00			`exporter := export.NewExporter(appSettings, version)`
feat: add cli parameters for db path and metrics port (#4) Add support for configuring CLI parameters in the application using a new `cfg` package. The `cfg` package exports an `AppSettings` struct that contains the settings the application was run with. Update the application to use the new CLI parameters to set the db to open and the port to use for the metrics server. Add support for setting the app version during build. The app includes a `-version` flag to print the stored version data. 2021-02-06 16:17:35 +01:00			`prometheus.MustRegister(exporter)`
feat: initial setup of metric exporter Add dependency on the prometheus library to start exporting metrics. Add a new `up` metric that always returns `1` to ensure the exporter is working as expected. 2021-02-06 00:01:00 +01:00
feat: support for textfile metrics (#13) Add support for collecting arbitrary metrics from a textfile as well as metrics collected from fail2ban. This allows other data to be exported along with the fail2ban metrics (e.g. instance metadata). Update the docker image to allow mounting a folder with a collection of metric files to be exported. Only files ending in `.prom` with be read. Update project README with the new functionality. 2021-10-12 22:38:26 +02:00			`textFileCollector := textfile.NewCollector(appSettings)`
			`prometheus.MustRegister(textFileCollector)`

feat: render basic html page at root url Add a new request handler for the root URL (`/`) to render a simple HTML page with a link to the metrics page. This follows the convention of other metric exporters. 2021-09-25 23:23:28 +02:00			`http.HandleFunc("/", rootHtmlHandler)`
feat: support for textfile metrics (#13) Add support for collecting arbitrary metrics from a textfile as well as metrics collected from fail2ban. This allows other data to be exported along with the fail2ban metrics (e.g. instance metadata). Update the docker image to allow mounting a folder with a collection of metric files to be exported. Only files ending in `.prom` with be read. Update project README with the new functionality. 2021-10-12 22:38:26 +02:00			`http.HandleFunc(metricsPath, func(w http.ResponseWriter, r *http.Request) {`
			`metricHandler(w, r, textFileCollector)`
			`})`
feat: improve startup logging Update the exporter startup to add more log messages. The server address, port, and metrics path are now logged on startup. A "ready" log message is printed when the server is up and running. 2021-09-21 10:34:23 +02:00			`log.Printf("metrics available at '%s'", metricsPath)`

			`svrErr := make(chan error)`
			`go func() {`
			`svrErr <- http.ListenAndServe(addr, nil)`
			`}()`
			`log.Print("ready")`

			`err := <-svrErr`
			`log.Print(err)`
feat: add cli parameters for db path and metrics port (#4) Add support for configuring CLI parameters in the application using a new `cfg` package. The `cfg` package exports an `AppSettings` struct that contains the settings the application was run with. Update the application to use the new CLI parameters to set the db to open and the port to use for the metrics server. Add support for setting the app version during build. The app includes a `-version` flag to print the stored version data. 2021-02-06 16:17:35 +01:00			`}`
initial commit 2021-02-05 23:49:47 +01:00			`}`