PostgreSQL Hook for Logrus   

Use this hook to send your logs to postgresql server.

Usage

The hook must be configured with:

• A postgresql db connection (**sql.DB)
• an optional hash with extra global fields. These fields will be included in all messages sent to postgresql

package main

import (
    log "github.com/sirupsen/logrus"
    "gopkg.in/gemnasium/logrus-postgresql-hook.v1"
    )

func main() {
    db, err := sql.Open("postgres", "user=postgres dbname=postgres host=postgres sslmode=disable")
      if err != nil {
        t.Fatal("Can't connect to postgresql database:", err)
      }
    defer db.Close()
    hook := pglogrus.NewHook(db, map[string]interface{}{"this": "is logged every time"})
    log.AddHook(hook)
    log.Info("some logging message")
}

Asynchronous logger

This package provides an asynchronous hook, so logging won't block waiting for the data to be inserted in the DB. Be careful to defer call hook.Flush() if you are using this kind of hook.

package main

import (
    log "github.com/sirupsen/logrus"
    "gopkg.in/gemnasium/logrus-postgresql-hook.v1"
    )

func main() {
    db, err := sql.Open("postgres", "user=postgres dbname=postgres host=postgres sslmode=disable")
      if err != nil {
        t.Fatal("Can't connect to postgresql database:", err)
      }
    defer db.Close()
    hook := pglogrus.NewAsyncHook(db, map[string]interface{}{"this": "is logged every time"})
    defer hook.Flush()
    log.AddHook(hook)
    log.Info("some logging message")
}

Customize insertion

By defaults, the hook will log into a logs table (cf the test schema in migrations). To change this behavior, set the InsertFunc of the hook:

package main

import (
    log "github.com/sirupsen/logrus"
    "gopkg.in/gemnasium/logrus-postgresql-hook.v1"
    )

func main() {
    db, err := sql.Open("postgres", "user=postgres dbname=postgres host=postgres sslmode=disable")
      if err != nil {
        t.Fatal("Can't connect to postgresql database:", err)
      }
    defer db.Close()

    hook := pglogrus.NewHook(db, map[string]interface{}{"this": "is logged every time"})
    hook.InsertFunc = func(db *sql.DB, entry *logrus.Entry) error {
      jsonData, err := json.Marshal(entry.Data)
        if err != nil {
          return err
        }

      _, err = db.Exec("INSERT INTO another_logs_table(level, message, message_data, created_at) VALUES ($1,$2,$3,$4);", entry.Level, entry.Message, jsonData, entry.Time)
        return err
    }
    log.AddHook(hook)
    log.Info("some logging message")

}

Ignore entries

Entries can be completely ignored using a filter. A filter a func(*logrus.Entry) *logrus.Entry that modifies or ignore the entry provided.

package main

import (
    log "github.com/sirupsen/logrus"
    "gopkg.in/gemnasium/logrus-postgresql-hook.v1"
    )

func main() {
    db, err := sql.Open("postgres", "user=postgres dbname=postgres host=postgres sslmode=disable")
      if err != nil {
        t.Fatal("Can't connect to postgresql database:", err)
      }
    defer db.Close()
    hook := pglogrus.NewAsyncHook(db, map[string]interface{}{"this": "is logged every time"})
    defer hook.Flush()

    hook.AddFilter(func(entry *logrus.Entry) *logrus.Entry {
      if _, ok := entry.Data["ignore"]; ok {
        // ignore entry
        entry = nil
      }
      return entry
    })

    log.Hooks.Add(hook)
    log.Info("some logging message")
    log.WithField("ignore", "me").Info("This message will be ignored")
}

Run tests

Since this hook is hitting a DB, we're testing again a real PostgreSQL server:

docker-compose run --rm test