Add Elasticsearch notification

Elsasticsearch notification: add test cases

Elasticsearch notification: make timeout configurable

Elsasticsearch notification: add @timestamp field to JSON data

Elsasticsearch notification: improve error handling

use context.WithTimeoutCause

Co-authored-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

better comment the elaticsearch api endpoint

add screenshot to documentation

docs/config/index.md

@@ -247,6 +247,7 @@ Can be transposed to:
     * [amqp](../notif/amqp.md)
     * [apprise](../notif/apprise.md)
     * [discord](../notif/discord.md)
+    * [elasticsearch](../notif/elasticsearch.md)
     * [gotify](../notif/gotify.md)
     * [mail](../notif/mail.md)
     * [matrix](../notif/matrix.md)

docs/config/notif.md

@@ -3,6 +3,7 @@
 * [`amqp`](../notif/amqp.md)
 * [`apprise`](../notif/apprise.md)
 * [`discord`](../notif/discord.md)
+* [`elasticsearch`](../notif/elasticsearch.md)
 * [`gotify`](../notif/gotify.md)
 * [`mail`](../notif/mail.md)
 * [`matrix`](../notif/matrix.md)

docs/notif/elasticsearch.md

@@ -0,0 +1,82 @@
+# Elasticsearch notifications
+
+Send notifications to your Elasticsearch cluster as structured documents.
+
+## Configuration
+
+!!! example "File"
+    ```yaml
+    notif:
+      elasticsearch:
+        scheme: https
+        host: localhost
+        port: 9200
+        username: elastic
+        password: password
+        client: diun
+        index: diun-notifications
+        timeout: 10s
+        insecureSkipVerify: false
+    ```
+
+| Name                 | Default              | Description                                                         |
+| -------------------- | -------------------- | ------------------------------------------------------------------- |
+| `scheme`[^1]         | `http`               | Elasticsearch scheme (`http` or `https`)                            |
+| `host`[^1]           | `localhost`          | Elasticsearch host                                                  |
+| `port`[^1]           | `9200`               | Elasticsearch port                                                  |
+| `username`           |                      | Elasticsearch username for authentication                           |
+| `usernameFile`       |                      | Use content of secret file as username if `username` is not defined |
+| `password`           |                      | Elasticsearch password for authentication                           |
+| `passwordFile`       |                      | Use content of secret file as password if `password` is not defined |
+| `client`[^1]         | `diun`               | Client name to identify the source of notifications                 |
+| `index`[^1]          | `diun-notifications` | Elasticsearch index name where notifications will be stored         |
+| `timeout`[^1]        | `10s`                | Timeout specifies a time limit for the request to be made           |
+| `insecureSkipVerify` | `false`              | Skip TLS certificate verification                                   |
+
+!!! abstract "Environment variables"
+    * `DIUN_NOTIF_ELASTICSEARCH_SCHEME`
+    * `DIUN_NOTIF_ELASTICSEARCH_HOST`
+    * `DIUN_NOTIF_ELASTICSEARCH_PORT`
+    * `DIUN_NOTIF_ELASTICSEARCH_USERNAME`
+    * `DIUN_NOTIF_ELASTICSEARCH_USERNAMEFILE`
+    * `DIUN_NOTIF_ELASTICSEARCH_PASSWORD`
+    * `DIUN_NOTIF_ELASTICSEARCH_PASSWORDFILE`
+    * `DIUN_NOTIF_ELASTICSEARCH_CLIENT`
+    * `DIUN_NOTIF_ELASTICSEARCH_INDEX`
+    * `DIUN_NOTIF_ELASTICSEARCH_TIMEOUT`
+    * `DIUN_NOTIF_ELASTICSEARCH_INSECURESKIPVERIFY`
+
+## Document Structure
+
+Each notification is stored as a JSON document with following structure:
+
+```json
+{
+  "diun_version": "4.24.0",
+  "hostname": "myserver",
+  "status": "new",
+  "provider": "file",
+  "image": "docker.io/crazymax/diun:latest",
+  "hub_link": "https://hub.docker.com/r/crazymax/diun",
+  "mime_type": "application/vnd.docker.distribution.manifest.list.v2+json",
+  "digest": "sha256:216e3ae7de4ca8b553eb11ef7abda00651e79e537e85c46108284e5e91673e01",
+  "created": "2020-03-26T12:23:56Z",
+  "platform": "linux/amd64",
+  "client": "diun",
+  "metadata": {
+    "ctn_command": "diun serve",
+    "ctn_createdat": "2022-12-29 10:22:15 +0100 CET",
+    "ctn_id": "0dbd10e15b31add2c48856fd34451adabf50d276efa466fe19a8ef5fbd87ad7c",
+    "ctn_names": "diun",
+    "ctn_size": "0B",
+    "ctn_state": "running",
+    "ctn_status": "Up Less than a second (health: starting)"
+  }
+}
+```
+
+## Sample
+
+![](../assets/notif/elasticsearch.png)
+
+[^1]: Value required

internal/config/config_test.go

@@ -94,6 +94,17 @@ func TestLoadFile(t *testing.T) {
 						Timeout:      utl.NewDuration(10 * time.Second),
 						TemplateBody: model.NotifDefaultTemplateBody,
 					},
+					Elasticsearch: &model.NotifElasticsearch{
+						Scheme:             "https",
+						Host:               "localhost",
+						Port:               9200,
+						Username:           "elastic",
+						Password:           "password",
+						Client:             "diun",
+						Index:              "diun-notifications",
+						Timeout:            utl.NewDuration(10 * time.Second),
+						InsecureSkipVerify: false,
+					},
 					Gotify: &model.NotifGotify{
 						Endpoint:      "http://gotify.foo.com",
 						Token:         "Token123456",

internal/config/fixtures/config.test.yml

@@ -39,6 +39,16 @@ notif:
       - "<@&200>"
     renderFields: true
     timeout: 10s
+  elasticsearch:
+    scheme: https
+    host: localhost
+    port: 9200
+    username: elastic
+    password: password
+    client: diun
+    index: diun-notifications
+    timeout: 10s
+    insecureSkipVerify: false
   gotify:
     endpoint: http://gotify.foo.com
     token: Token123456

internal/config/fixtures/config.validate.yml

@@ -28,6 +28,16 @@ notif:
       - "<@&200>"
     renderFields: true
     timeout: 10s
+  elasticsearch:
+    scheme: https
+    host: localhost
+    port: 9200
+    username: elastic
+    password: password
+    client: diun
+    index: diun-notifications
+    timeout: 10s
+    insecureSkipVerify: false
   gotify:
     endpoint: http://gotify.foo.com
     token: Token123456

internal/model/notif.go

@@ -35,6 +35,7 @@ type Notif struct {
 	Amqp          *NotifAmqp          `yaml:"amqp,omitempty" json:"amqp,omitempty"`
 	Apprise       *NotifApprise       `yaml:"apprise,omitempty" json:"apprise,omitempty"`
 	Discord       *NotifDiscord       `yaml:"discord,omitempty" json:"discord,omitempty"`
+	Elasticsearch *NotifElasticsearch `yaml:"elasticsearch,omitempty" json:"elasticsearch,omitempty"`
 	Gotify        *NotifGotify        `yaml:"gotify,omitempty" json:"gotify,omitempty"`
 	Mail          *NotifMail          `yaml:"mail,omitempty" json:"mail,omitempty"`
 	Matrix        *NotifMatrix        `yaml:"matrix,omitempty" json:"matrix,omitempty"`

internal/model/notif_elasticsearch.go

@@ -0,0 +1,39 @@
+package model
+
+import (
+	"time"
+
+	"github.com/crazy-max/diun/v4/pkg/utl"
+)
+
+type NotifElasticsearch struct {
+	Scheme             string         `yaml:"scheme,omitempty" json:"scheme,omitempty" validate:"required,oneof=http https"`
+	Host               string         `yaml:"host,omitempty" json:"host,omitempty" validate:"required"`
+	Port               int            `yaml:"port,omitempty" json:"port,omitempty" validate:"required,min=1"`
+	Username           string         `yaml:"username,omitempty" json:"username,omitempty" validate:"omitempty"`
+	UsernameFile       string         `yaml:"usernameFile,omitempty" json:"usernameFile,omitempty" validate:"omitempty,file"`
+	Password           string         `yaml:"password,omitempty" json:"password,omitempty" validate:"omitempty"`
+	PasswordFile       string         `yaml:"passwordFile,omitempty" json:"passwordFile,omitempty" validate:"omitempty,file"`
+	Client             string         `yaml:"client,omitempty" json:"client,omitempty" validate:"required"`
+	Index              string         `yaml:"index,omitempty" json:"index,omitempty" validate:"required"`
+	Timeout            *time.Duration `yaml:"timeout,omitempty" json:"timeout,omitempty" validate:"required"`
+	InsecureSkipVerify bool           `yaml:"insecureSkipVerify,omitempty" json:"insecureSkipVerify,omitempty" validate:"omitempty"`
+}
+
+// GetDefaults gets the default values
+func (s *NotifElasticsearch) GetDefaults() *NotifElasticsearch {
+	n := &NotifElasticsearch{}
+	n.SetDefaults()
+	return n
+}
+
+// SetDefaults sets the default values
+func (s *NotifElasticsearch) SetDefaults() {
+	s.Scheme = "http"
+	s.Host = "localhost"
+	s.Port = 9200
+	s.Client = "diun"
+	s.Index = "diun-notifications"
+	s.Timeout = utl.NewDuration(10 * time.Second)
+	s.InsecureSkipVerify = false
+}

internal/notif/client.go

@@ -7,6 +7,7 @@ import (
 	"github.com/crazy-max/diun/v4/internal/notif/amqp"
 	"github.com/crazy-max/diun/v4/internal/notif/apprise"
 	"github.com/crazy-max/diun/v4/internal/notif/discord"
+	"github.com/crazy-max/diun/v4/internal/notif/elasticsearch"
 	"github.com/crazy-max/diun/v4/internal/notif/gotify"
 	"github.com/crazy-max/diun/v4/internal/notif/mail"
 	"github.com/crazy-max/diun/v4/internal/notif/matrix"
@@ -54,6 +55,9 @@ func New(config *model.Notif, meta model.Meta) (*Client, error) {
 	if config.Discord != nil {
 		c.notifiers = append(c.notifiers, discord.New(config.Discord, meta))
 	}
+	if config.Elasticsearch != nil {
+		c.notifiers = append(c.notifiers, elasticsearch.New(config.Elasticsearch, meta))
+	}
 	if config.Gotify != nil {
 		c.notifiers = append(c.notifiers, gotify.New(config.Gotify, meta))
 	}

internal/notif/elasticsearch/client.go

@@ -0,0 +1,137 @@
+package elasticsearch
+
+import (
+	"bytes"
+	"context"
+	"crypto/tls"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/crazy-max/diun/v4/internal/model"
+	"github.com/crazy-max/diun/v4/internal/msg"
+	"github.com/crazy-max/diun/v4/internal/notif/notifier"
+	"github.com/crazy-max/diun/v4/pkg/utl"
+	"github.com/pkg/errors"
+)
+
+// Client represents an active elasticsearch notification object
+type Client struct {
+	*notifier.Notifier
+	cfg  *model.NotifElasticsearch
+	meta model.Meta
+}
+
+// New creates a new elasticsearch notification instance
+func New(config *model.NotifElasticsearch, meta model.Meta) notifier.Notifier {
+	return notifier.Notifier{
+		Handler: &Client{
+			cfg:  config,
+			meta: meta,
+		},
+	}
+}
+
+// Name returns notifier's name
+func (c *Client) Name() string {
+	return "elasticsearch"
+}
+
+// Send creates and sends an elasticsearch notification with an entry
+func (c *Client) Send(entry model.NotifEntry) error {
+	username, err := utl.GetSecret(c.cfg.Username, c.cfg.UsernameFile)
+	if err != nil {
+		return err
+	}
+
+	password, err := utl.GetSecret(c.cfg.Password, c.cfg.PasswordFile)
+	if err != nil {
+		return err
+	}
+
+	// Use the same JSON structure as webhook notifier
+	message, err := msg.New(msg.Options{
+		Meta:  c.meta,
+		Entry: entry,
+	})
+	if err != nil {
+		return err
+	}
+
+	body, err := message.RenderJSON()
+	if err != nil {
+		return err
+	}
+
+	// Parse the JSON to add the client field
+	var doc map[string]any
+	if err := json.Unmarshal(body, &doc); err != nil {
+		return err
+	}
+
+	// Add the current time
+	doc["@timestamp"] = time.Now().Format(time.RFC3339Nano)
+
+	// Add the client field from the configuration
+	doc["client"] = c.cfg.Client
+
+	// Re-marshal the JSON with the client field
+	body, err = json.Marshal(doc)
+	if err != nil {
+		return err
+	}
+
+	// Build the Elasticsearch indexing URL
+	// This uses the Index API (POST /{index}/_doc) to create a document with an auto-generated _id:
+	// https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-create
+	url := fmt.Sprintf("%s://%s:%d/%s/_doc", c.cfg.Scheme, c.cfg.Host, c.cfg.Port, c.cfg.Index)
+
+	cancelCtx, cancel := context.WithCancelCause(context.Background())
+	timeoutCtx, _ := context.WithTimeoutCause(cancelCtx, *c.cfg.Timeout, errors.WithStack(context.DeadlineExceeded)) //nolint:govet // no need to manually cancel this context as we already rely on parent
+	defer func() { cancel(errors.WithStack(context.Canceled)) }()
+
+	hc := http.Client{
+		Transport: &http.Transport{
+			TLSClientConfig: &tls.Config{
+				InsecureSkipVerify: c.cfg.InsecureSkipVerify,
+			},
+		},
+	}
+
+	req, err := http.NewRequestWithContext(timeoutCtx, "POST", url, bytes.NewBuffer(body))
+	if err != nil {
+		return err
+	}
+
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("User-Agent", c.meta.UserAgent)
+
+	// Add authentication if provided
+	if username != "" && password != "" {
+		req.SetBasicAuth(username, password)
+	}
+
+	resp, err := hc.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusCreated {
+		var errBody struct {
+			Status int `json:"status"`
+			Error  struct {
+				Type   string `json:"type"`
+				Reason string `json:"reason"`
+			} `json:"error"`
+		}
+		if err := json.NewDecoder(resp.Body).Decode(&errBody); err != nil {
+			return errors.Wrapf(err, "cannot decode JSON error response for HTTP %d %s status",
+				resp.StatusCode, http.StatusText(resp.StatusCode))
+		}
+		return errors.Errorf("%d %s: %s", errBody.Status, errBody.Error.Type, errBody.Error.Reason)
+	}
+
+	return nil
+}

mkdocs.yml

@@ -120,6 +120,7 @@ nav:
     - Amqp: notif/amqp.md
     - Apprise: notif/apprise.md
     - Discord: notif/discord.md
+    - Elasticsearch: notif/elasticsearch.md
     - Gotify: notif/gotify.md
     - Mail: notif/mail.md
     - Matrix: notif/matrix.md