Refactor body parsing

README.md

@@ -2,6 +2,8 @@
 
 An HTTP server which used to handle webhooks triggered by [OpenDistro for Elasticsearch Alerting](https://opendistro.github.io/for-elasticsearch-docs/docs/alerting)
 
+> Notice, the readme is for `0.2.x` version
+
 ## Why?
 
 As for time  of writing `destination` options that `ODFE` provides are limited.
@@ -46,26 +48,37 @@ Download latest version for your platform from [releases](https://github.com/bri
 
 1. Go to `Alerting` > `Destinations`
 2. Create the destination with type `Custom webhook`
-3. Chose `Define endpoint by custom attributes URL`
+3. Choose `Define endpoint by URL`
+    - For `slack` set the url to have path with `/slack`, like `http://odfe-server:8080/slack`
+    - For `email` set the url to have path with `/email`, like `http://odfe-server:8080/email`
+
+### Sending Email from triggers
 
-Fill in `Type`, `Host` and `Port` according to how and where you installed `odfe-alerts-handler`.
+1. Select destination which was created with the `/email` path
+2. The `Message` body look like below:
 
-### Configuring for Email
+```yaml
+to: ['[email protected]']
+subject: ['Optional subject param']
+---
+This is the body of the message
+Here you can use the templeting as usual...
+```
 
-1. Set `Path` to `email`
-2. Set `Query parameters` as follows:
-    - Key: `addresses`
-    - Value: comma separated list of emails to send
+`subject` is optional, if not provided the default one, see [#usage](usage).
 
-You can also override the default subject.
-If the first line of the alert message contains `Subject:`, that line will be used as a subject for the email.
+### Sending Slack from triggers
 
-### Configuring for Slack
+1. Select destination which was created with the `/slack` path
+2. The `Message` body look like below:
 
-1. Set `Path` to `slack`
-2. Set `Query parameters` as follows:
-    - Key: `channels` or `users`
-    - Value: comma separated list of user **emails** or list of channels
+```yaml
+channels: ['#alerts']
+users: ['[email protected]']
+---
+This is the body of the message
+Here you can use the templeting as usual...
+```
 
 You can have both `channels` and `users` keys if you desire to send to both.
 Optionally, for `channels` you can omit the leading `#`.
@@ -74,7 +87,7 @@ Optionally, for `channels` you can omit the leading `#`.
 
 ```shell
 RELEASE_TITLE="First release"
-RELEASE_VERSION=0.1.0
+RELEASE_VERSION=0.2.0
 
 git tag -a v${RELEASE_VERSION} -m "${RELEASE_TITLE}"
 git push --tags

go.mod

@@ -12,4 +12,5 @@ require (
 	github.com/nlopes/slack v0.6.0
 	golang.org/x/crypto v0.0.0-20190829043050-9756ffdc2472 // indirect
 	gopkg.in/alecthomas/kingpin.v2 v2.2.6
+	gopkg.in/yaml.v2 v2.2.2
 )

handlers/common.go

@@ -1,9 +1,34 @@
 package handlers
 
-import "strings"
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"regexp"
 
-func fields(s string, sep rune) []string {
-	return strings.FieldsFunc(s, func(c rune) bool {
-		return c == sep
-	})
+	"gopkg.in/yaml.v2"
+)
+
+var bodySep = regexp.MustCompile("(?:^|\\s*\n)---\\s*")
+
+func parseBody(requestBody io.ReadCloser, target interface{}) (string, error) {
+	body, err := ioutil.ReadAll(requestBody)
+
+	if err != nil {
+		return "", fmt.Errorf("failed to read body, %v", err)
+	}
+
+	docs := bodySep.Split(string(body), 2)
+
+	if len(docs) != 2 {
+		return "", fmt.Errorf("cannot split body, got %d elements after split, but 2 elements required", len(docs))
+	}
+
+	params, data := []byte(docs[0]), docs[1]
+
+	if err := yaml.Unmarshal(params, target); err != nil {
+		return "", fmt.Errorf("cannot unmarshal params, %v", err)
+	}
+
+	return data, nil
 }

handlers/email.go

@@ -1,23 +1,17 @@
 package handlers
 
 import (
-	"bufio"
-	"bytes"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/smtp"
-	"regexp"
 	"strconv"
 
 	emailClient "github.com/jordan-wright/email"
 	"github.com/labstack/echo/v4"
 	"github.com/labstack/gommon/log"
 )
 
-var subjectRe = regexp.MustCompile(`(?i)^(\s+)?subject:(\s+)?`)
-
 // Email used to configure common params for sending email
 type Email struct {
 	Host           string
@@ -30,31 +24,18 @@ type Email struct {
 
 // email used by the handler to set params per incoming request
 type email struct {
-	Email
+	*Email
 
-	subject string
-	to      []string
+	Subject string
+	To      []string
 	data    []byte
 }
 
-func (e *email) prepareSubject() {
-	scanner := bufio.NewScanner(bytes.NewReader(e.data))
-	scanner.Scan()
-
-	if subjectRe.Match(scanner.Bytes()) {
-		e.subject = subjectRe.ReplaceAllString(scanner.Text(), "")
-		e.data = e.data[len(scanner.Bytes()):]
-		return
-	}
-
-	e.subject = e.DefaultSubject
-}
-
 func (e *email) send() error {
 	client := &emailClient.Email{
-		To:      e.to,
+		To:      e.To,
 		From:    e.From,
-		Subject: e.subject,
+		Subject: e.Subject,
 		Text:    e.data,
 	}
 
@@ -68,40 +49,38 @@ func (e *email) send() error {
 
 // EchoHandler sends email per each incoming http request
 func (e Email) EchoHandler(c echo.Context) error {
-	addresses := fields(c.QueryParam("addresses"), ',')
-
-	if len(addresses) == 0 {
-		response := "email was not sent, no addresses param provided"
-
-		log.Error(response)
-		return echo.NewHTTPError(http.StatusBadRequest, response)
+	emailer := email{
+		Email:   &e,
+		Subject: e.DefaultSubject,
 	}
 
 	defer c.Request().Body.Close()
-	requestBody, err := ioutil.ReadAll(c.Request().Body)
+	data, err := parseBody(c.Request().Body, &emailer)
+
 	if err != nil {
-		response := fmt.Sprintf("email was not sent, failed to read body, %v", err)
+		response := fmt.Sprintf("email was not sent, %v", err)
 
 		log.Error(response)
 		return echo.NewHTTPError(http.StatusInternalServerError, response)
 	}
 
-	emailer := email{
-		Email: e,
-		data:  requestBody,
-		to:    addresses,
+	if len(emailer.To) == 0 {
+		response := "email was not sent, 'To' param wasn't provided"
+
+		log.Error(response)
+		return echo.NewHTTPError(http.StatusBadRequest, response)
 	}
 
-	emailer.prepareSubject()
+	emailer.data = []byte(data)
 
 	if err := emailer.send(); err != nil {
-		response := fmt.Sprintf("email was not sent, to: %v, subject: %s, %v", addresses, emailer.subject, err)
+		response := fmt.Sprintf("email was not sent, to: %v, subject: %s, %v", emailer.To, emailer.Subject, err)
 
 		log.Error(response)
 		return echo.NewHTTPError(http.StatusInternalServerError, response)
 	}
 
-	response := fmt.Sprintf("email successfuly sent, to: %v, subject: %s", addresses, emailer.subject)
+	response := fmt.Sprintf("email successfuly sent, to: %v, subject: %s", emailer.To, emailer.Subject)
 	log.Info(response)
 	return echo.NewHTTPError(http.StatusOK, response)
 }

handlers/slack.go

@@ -2,7 +2,6 @@ package handlers
 
 import (
 	"fmt"
-	"io/ioutil"
 	"net/http"
 	"strings"
 
@@ -20,10 +19,10 @@ type Slack struct {
 
 // slack used by the handler to set params per incoming request
 type slack struct {
-	Slack
+	*Slack `yaml:"-"`
 
-	channels []string
-	users    []string
+	Channels []string
+	Users    []string
 	text     string
 }
 
@@ -38,7 +37,7 @@ func (s *slack) getClient() *slackAPI.Client {
 func (s slack) postToChannels() error {
 	var result error
 
-	for _, channel := range s.channels {
+	for _, channel := range s.Channels {
 		if !strings.HasPrefix(channel, "#") {
 			channel = "#" + channel
 		}
@@ -54,7 +53,7 @@ func (s slack) postToChannels() error {
 func (s slack) postToUsers() error {
 	var result error
 
-	for _, user := range s.users {
+	for _, user := range s.Users {
 
 		user, err := s.getClient().GetUserByEmail(user)
 		if err != nil {
@@ -80,13 +79,13 @@ func (s slack) postToUsers() error {
 func (s slack) post() error {
 	var result error
 
-	if len(s.channels) > 0 {
+	if len(s.Channels) > 0 {
 		if err := s.postToChannels(); err != nil {
 			result = multierror.Append(result, err)
 		}
 	}
 
-	if len(s.users) > 0 {
+	if len(s.Users) > 0 {
 		if err := s.postToUsers(); err != nil {
 			result = multierror.Append(result, err)
 		}
@@ -104,39 +103,37 @@ func (s Slack) EchoHandler(c echo.Context) error {
 		return echo.NewHTTPError(http.StatusUnprocessableEntity, response)
 	}
 
-	channels, users := fields(c.QueryParam("channels"), ','), fields(c.QueryParam("users"), ',')
-
-	if len(channels) == 0 && len(users) == 0 {
-		response := "slack message was not sent, no channels or users params provided"
-
-		log.Error(response)
-		return echo.NewHTTPError(http.StatusBadRequest, response)
+	slacker := slack{
+		Slack: &s,
 	}
 
 	defer c.Request().Body.Close()
-	requestBody, err := ioutil.ReadAll(c.Request().Body)
+	text, err := parseBody(c.Request().Body, &slacker)
+
 	if err != nil {
-		response := fmt.Sprintf("slack message was not sent, failed to read body, %v", err)
+		response := fmt.Sprintf("slack message was not sent, %v", err)
 
 		log.Error(response)
 		return echo.NewHTTPError(http.StatusInternalServerError, response)
 	}
 
-	slacker := slack{
-		Slack:    s,
-		channels: channels,
-		users:    users,
-		text:     string(requestBody),
+	if len(slacker.Channels) == 0 && len(slacker.Users) == 0 {
+		response := "slack message was not sent, no channels or users params provided"
+
+		log.Error(response)
+		return echo.NewHTTPError(http.StatusBadRequest, response)
 	}
 
+	slacker.text = text
+
 	if err := slacker.post(); err != nil {
-		response := fmt.Sprintf("slack message was not sent, channels: %v, users: %v, %v", channels, users, err)
+		response := fmt.Sprintf("slack message was not sent, channels: %v, users: %v, %v", slacker.Channels, slacker.Users, err)
 
 		log.Error(response)
 		return echo.NewHTTPError(http.StatusInternalServerError, response)
 	}
 
-	response := fmt.Sprintf("slack message successfuly sent, channels: %v, users: %v", channels, users)
+	response := fmt.Sprintf("slack message successfuly sent, channels: %v, users: %v", slacker.Channels, slacker.Users)
 	log.Info(response)
 	return echo.NewHTTPError(http.StatusOK, response)
 }