Deprecate extend queries feature (#811)

Mark the extend queries feature as deprecated in favor of recommending
the sql_exporter.

Signed-off-by: SuperQ <[email protected]>

Author: SuperQ

README.md

@@ -105,7 +105,7 @@ This will build the docker image as `prometheuscommunity/postgres_exporter:${bra
 * `auto-discover-databases`
   Whether to discover the databases on a server dynamically.  Default is `false`.
 
-* `extend.query-path`
+* `extend.query-path` (DEPRECATED)
   Path to a YAML file containing custom queries to run. Check out [`queries.yaml`](queries.yaml)
   for examples of the format.
 
@@ -222,7 +222,9 @@ for l in StringIO(x):
 Adjust the value of the resultant prometheus value type appropriately. This helps build
 rich self-documenting metrics for the exporter.
 
-### Adding new metrics via a config file
+### Adding new metrics via a config file (DEPRECATED)
+
+This feature is deprecated in favor of built-in collector functions. For generic SQL database monitoring see the [sql_exporter](https://github.com/burningalchemist/sql_exporter).
 
 The -extend.query-path command-line argument specifies a YAML file containing additional queries to run.
 Some examples are provided in [queries.yaml](queries.yaml).

cmd/postgres_exporter/main.go

@@ -44,7 +44,7 @@ var (
 	disableDefaultMetrics  = kingpin.Flag("disable-default-metrics", "Do not include default metrics.").Default("false").Envar("PG_EXPORTER_DISABLE_DEFAULT_METRICS").Bool()
 	disableSettingsMetrics = kingpin.Flag("disable-settings-metrics", "Do not include pg_settings metrics.").Default("false").Envar("PG_EXPORTER_DISABLE_SETTINGS_METRICS").Bool()
 	autoDiscoverDatabases  = kingpin.Flag("auto-discover-databases", "Whether to discover the databases on a server dynamically.").Default("false").Envar("PG_EXPORTER_AUTO_DISCOVER_DATABASES").Bool()
-	queriesPath            = kingpin.Flag("extend.query-path", "Path to custom queries to run.").Default("").Envar("PG_EXPORTER_EXTEND_QUERY_PATH").String()
+	queriesPath            = kingpin.Flag("extend.query-path", "Path to custom queries to run. (DEPRECATED)").Default("").Envar("PG_EXPORTER_EXTEND_QUERY_PATH").String()
 	onlyDumpMaps           = kingpin.Flag("dumpmaps", "Do not run, simply dump the maps.").Bool()
 	constantLabelsList     = kingpin.Flag("constantLabels", "A list of label=value separated by comma(,).").Default("").Envar("PG_EXPORTER_CONSTANT_LABELS").String()
 	excludeDatabases       = kingpin.Flag("exclude-databases", "A list of databases to remove when autoDiscoverDatabases is enabled").Default("").Envar("PG_EXPORTER_EXCLUDE_DATABASES").String()
@@ -95,6 +95,10 @@ func main() {
 	excludedDatabases := strings.Split(*excludeDatabases, ",")
 	logger.Log("msg", "Excluded databases", "databases", fmt.Sprintf("%v", excludedDatabases))
 
+	if *queriesPath != "" {
+		level.Warn(logger).Log("msg", "The extend queries.yaml config is DEPRECATD", "file", *queriesPath)
+	}
+
 	opts := []ExporterOpt{
 		DisableDefaultMetrics(*disableDefaultMetrics),
 		DisableSettingsMetrics(*disableSettingsMetrics),