fix: reload query targets (#23)

* fix: reload query collectors - part 2
* deps: update dependencies
* fix: address security recommendations
* chore: update CodeQL workflow
* chore: small wording changes

Author: burningalchemist

.github/workflows/codeql-analysis.yml

@@ -31,11 +31,6 @@ jobs:
         # a pull request then we can checkout the head.
         fetch-depth: 2
 
-    # If this run was triggered by a pull request event, then checkout
-    # the head of the pull request instead of the merge commit.
-    - run: git checkout HEAD^2
-      if: ${{ github.event_name == 'pull_request' }}
-
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
       uses: github/codeql-action/init@v1

VERSION

@@ -1 +1 @@
-0.8.1
+0.8.2

cmd/sql_exporter/main.go

@@ -18,11 +18,11 @@ import (
 )
 
 var (
-	showVersion   = flag.Bool("version", false, "Print version information.")
-	listenAddress = flag.String("web.listen-address", ":9399", "Address to listen on for web interface and telemetry.")
-	metricsPath   = flag.String("web.metrics-path", "/metrics", "Path under which to expose metrics.")
-	enableReload  = flag.Bool("web.enable-reload", false, "Enable reload collector data handler.")
-	configFile    = flag.String("config.file", "sql_exporter.yml", "SQL Exporter configuration file name.")
+	showVersion   = flag.Bool("version", false, "Print version information")
+	listenAddress = flag.String("web.listen-address", ":9399", "Address to listen on for web interface and telemetry")
+	metricsPath   = flag.String("web.metrics-path", "/metrics", "Path under which to expose metrics")
+	enableReload  = flag.Bool("web.enable-reload", false, "Enable reload collector data handler")
+	configFile    = flag.String("config.file", "sql_exporter.yml", "SQL Exporter configuration filename")
 )
 
 func init() {
@@ -80,12 +80,21 @@ func main() {
 func reloadCollectors(e sql_exporter.Exporter) func(http.ResponseWriter, *http.Request) {
 	return func(w http.ResponseWriter, r *http.Request) {
 		klog.Infof("Reloading the collectors...")
-		err := e.Config().ReloadCollectorFiles()
-		if err != nil {
-			klog.Errorf("Error reloading collectors - %v", err)
+		config := e.Config()
+		if err := config.ReloadCollectorFiles(); err != nil {
+			klog.Errorf("Error reloading collector configs - %v", err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 		}
-		http.Error(w, `Query collectors have been reloaded`, http.StatusOK)
+
+		// FIXME: Should be t.Collectors() instead of config.Collectors
+		target, err := sql_exporter.NewTarget("", "", string(config.Target.DSN), config.Collectors, nil, config.Globals)
+		if err != nil {
+			klog.Errorf("Error creating a new target - %v", err)
+		}
+		e.UpdateTarget([]sql_exporter.Target{target})
+
+		klog.Infof("Query collectors have been successfuly reloaded")
+		w.WriteHeader(http.StatusNoContent)
 	}
 }
 

config/config.go

@@ -13,6 +13,8 @@ import (
 	"k8s.io/klog/v2"
 )
 
+const MaxInt32 int = 1<<31 - 1
+
 // Load attempts to parse the given config file and return a Config object.
 func Load(configFile string) (*Config, error) {
 	klog.Infof("Loading configuration from %s", configFile)
@@ -266,6 +268,7 @@ func (j *JobConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	return checkOverflow(j.XXX, "job")
 }
 
+//lint:ignore U1000 - it's unused so far
 // checkLabelCollisions checks for label collisions between StaticConfig labels and Metric labels.
 func (j *JobConfig) checkLabelCollisions() error {
 	sclabels := make(map[string]interface{})

exporter.go

@@ -2,6 +2,7 @@ package sql_exporter
 
 import (
 	"context"
+	"errors"
 	"flag"
 	"fmt"
 	"sync"
@@ -22,6 +23,7 @@ type Exporter interface {
 	WithContext(context.Context) Exporter
 	// Config returns the Exporter's underlying Config object.
 	Config() *config.Config
+	UpdateTarget([]Target)
 }
 
 type exporter struct {
@@ -41,7 +43,7 @@ func NewExporter(configFile string) (Exporter, error) {
 	// Override the DSN if requested (and in single target mode).
 	if *dsnOverride != "" {
 		if len(c.Jobs) > 0 {
-			return nil, fmt.Errorf("The config.data-source-name flag (value %q) only applies in single target mode", *dsnOverride)
+			return nil, fmt.Errorf("the config.data-source-name flag (value %q) only applies in single target mode", *dsnOverride)
 		}
 		c.Target.DSN = config.Secret(*dsnOverride)
 	}
@@ -54,6 +56,9 @@ func NewExporter(configFile string) (Exporter, error) {
 		}
 		targets = []Target{target}
 	} else {
+		if len(c.Jobs) > (config.MaxInt32 / 3) {
+			return nil, errors.New("'jobs' list is too large")
+		}
 		targets = make([]Target, 0, len(c.Jobs)*3)
 		for _, jc := range c.Jobs {
 			job, err := NewJob(jc, c.Globals)
@@ -147,3 +152,7 @@ func (e *exporter) Gather() ([]*dto.MetricFamily, error) {
 func (e *exporter) Config() *config.Config {
 	return e.config
 }
+
+func (e *exporter) UpdateTarget(target []Target) {
+	e.targets = target
+}

go.mod

@@ -4,32 +4,34 @@ go 1.14
 
 require (
 	github.com/ClickHouse/clickhouse-go v1.4.3
-	github.com/apache/arrow/go/arrow v0.0.0-20210312155728-26fc75157af2 // indirect
+	github.com/apache/arrow/go/arrow v0.0.0-20210404094439-beb1c1b35be1 // indirect
+	github.com/aws/aws-sdk-go-v2/credentials v1.1.4 // indirect
+	github.com/aws/aws-sdk-go-v2/service/s3 v1.4.0 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/denisenkom/go-mssqldb v0.9.0
-	github.com/go-sql-driver/mysql v1.5.0
+	github.com/go-sql-driver/mysql v1.6.0
+	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/google/flatbuffers v1.12.0 // indirect
 	github.com/google/uuid v1.2.0 // indirect
 	github.com/jackc/pgproto3/v2 v2.0.7 // indirect
-	github.com/jackc/pgx/v4 v4.10.1
+	github.com/jackc/pgx/v4 v4.11.0
 	github.com/kardianos/minwinsvc v1.0.0
 	github.com/lib/pq v1.10.0
 	github.com/matttproud/golang_protobuf_extensions v1.0.2-0.20181231171920-c182affec369 // indirect
 	github.com/pkg/browser v0.0.0-20210115035449-ce105d075bb4 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
-	github.com/prometheus/client_golang v1.9.0
+	github.com/prometheus/client_golang v1.10.0
 	github.com/prometheus/client_model v0.2.0
-	github.com/prometheus/common v0.18.0
-	github.com/prometheus/procfs v0.6.0 // indirect
-	github.com/snowflakedb/gosnowflake v1.3.12
+	github.com/prometheus/common v0.20.0
+	github.com/sirupsen/logrus v1.8.1 // indirect
+	github.com/snowflakedb/gosnowflake v1.4.2
 	github.com/stretchr/testify v1.6.2-0.20200803095430-a3bed97cf337 // indirect
 	github.com/vertica/vertica-sql-go v1.1.1
-	golang.org/x/crypto v0.0.0-20210220033148-5ea612d1eb83 // indirect
-	golang.org/x/sys v0.0.0-20210309074719-68d13333faf2 // indirect
-	golang.org/x/text v0.3.5 // indirect
-	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
-	google.golang.org/protobuf v1.25.1-0.20200728163639-5d63473da8fb
+	golang.org/x/net v0.0.0-20210331212208-0fccb6fa2b5c // indirect
+	golang.org/x/sys v0.0.0-20210403161142-5e06dd20ab57 // indirect
+	golang.org/x/text v0.3.6 // indirect
+	google.golang.org/protobuf v1.26.0
 	gopkg.in/yaml.v2 v2.4.0
 	gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 // indirect
-	k8s.io/klog/v2 v2.7.0
+	k8s.io/klog/v2 v2.8.0
 )