Add Go command implementations

.gitignore

@@ -2,3 +2,6 @@
 *.rej
 .*.swp
 /.idea/
+/matrix-host-notification
+/matrix-service-notification
+dist/

cmd/matrix-host-notification/main.go

@@ -0,0 +1,71 @@
+// Copyright Jan Dittberner
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+// The main package for matrix-host-notification
+package main
+
+import (
+	"flag"
+	"log"
+	"os"
+
+	"git.ditberner.info/jan/icinga2-matrix-notification/internal/icinga2"
+	"git.ditberner.info/jan/icinga2-matrix-notification/internal/matrix"
+)
+
+func main() {
+	config := parseFlags()
+
+	message, err := icinga2.BuildHostNotification(config)
+	if err != nil {
+		log.Fatalf("could not build message: %v", err)
+	}
+
+	if err := matrix.SendMessage(config.MatrixServer.URL, config.MatrixRoom, config.MatrixToken, message); err != nil {
+		log.Fatalf("could not send message: %v", err)
+	}
+}
+
+func parseFlags() *icinga2.HostParameters {
+	config := &icinga2.HostParameters{}
+
+	flag.StringVar(&config.LongDateTime, "d", "", "long date time ($icinga.long_date_time$)")
+	flag.StringVar(&config.Hostname, "l", "", "hostname ($host.name$)")
+	flag.StringVar(&config.HostDisplayName, "n", "", "host display name ($host.display_name$)")
+
+	flag.StringVar(&config.HostOutput, "o", "", "host output ($host.output$)")
+	flag.StringVar(&config.HostState, "s", "", "host state ($host.state$)")
+
+	flag.StringVar(&config.MatrixRoom, "m", "", "matrix room ($notification_matrix_room$)")
+	flag.Var(&config.MatrixServer, "x", "matrix server ($notification_matrix_server$)")
+	flag.StringVar(&config.MatrixToken, "y", "", "matrix access token ($notification_matrix_token$)")
+
+	flag.StringVar(&config.HostAddress, "4", "", "host address ($address$)")
+	flag.StringVar(&config.HostAddress6, "6", "", "host address ($address6$)")
+	flag.StringVar(&config.NotificationAuthorName, "b", "", "notification author name ($notification.author_name$)")
+	flag.StringVar(&config.NotificationComment, "c", "", "notification comment ($notification.comment$)")
+	flag.Var(&config.IcingaWeb2URL, "i", "IcingaWeb 2 URL ($notification_icingaweb2url$)")
+
+	flag.Parse()
+
+	if err := config.ValidateRequired(); err != nil {
+		flag.Usage()
+
+		os.Exit(2) //nolint:mnd
+	}
+
+	return config
+}

cmd/matrix-service-notification/main.go

@@ -0,0 +1,73 @@
+// Copyright Jan Dittberner
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+package main
+
+import (
+	"flag"
+	"log"
+	"os"
+
+	"git.ditberner.info/jan/icinga2-matrix-notification/internal/icinga2"
+	"git.ditberner.info/jan/icinga2-matrix-notification/internal/matrix"
+)
+
+func main() {
+	parameters := parseFlags()
+
+	message, err := icinga2.BuildServiceNotification(parameters)
+	if err != nil {
+		log.Fatalf("could not build message: %v", err)
+	}
+
+	if err := matrix.SendMessage(
+		parameters.MatrixServer.URL, parameters.MatrixRoom, parameters.MatrixToken, message,
+	); err != nil {
+		log.Fatalf("could not send message: %v", err)
+	}
+}
+
+func parseFlags() *icinga2.ServiceParameters {
+	parameters := &icinga2.ServiceParameters{}
+
+	flag.StringVar(&parameters.LongDateTime, "d", "", "long date time ($icinga.long_date_time$)")
+	flag.StringVar(&parameters.Hostname, "l", "", "hostname ($host.name$)")
+	flag.StringVar(&parameters.HostDisplayName, "n", "", "host display name ($host.display_name$)")
+
+	flag.StringVar(&parameters.ServiceName, "e", "", "service name ($service.name$)")
+	flag.StringVar(&parameters.ServiceDisplayName, "u", "", "service display name ($service.display_name$)")
+	flag.StringVar(&parameters.ServiceOutput, "o", "", "service output ($service.output$)")
+	flag.StringVar(&parameters.ServiceState, "s", "", "service state ($service.state$)")
+
+	flag.StringVar(&parameters.MatrixRoom, "m", "", "matrix room ($notification_matrix_room$)")
+	flag.Var(&parameters.MatrixServer, "x", "matrix server ($notification_matrix_server$)")
+	flag.StringVar(&parameters.MatrixToken, "y", "", "matrix access token ($notification_matrix_token$)")
+
+	flag.StringVar(&parameters.HostAddress, "4", "", "host address ($address$)")
+	flag.StringVar(&parameters.HostAddress6, "6", "", "host address ($address6$)")
+	flag.StringVar(&parameters.NotificationAuthorName, "b", "", "notification author name ($notification.author_name$)")
+	flag.StringVar(&parameters.NotificationComment, "c", "", "notification comment ($notification.comment$)")
+	flag.Var(&parameters.IcingaWeb2URL, "i", "IcingaWeb 2 URL ($notification_icingaweb2url$)")
+
+	flag.Parse()
+
+	if err := parameters.ValidateRequired(); err != nil {
+		flag.Usage()
+
+		os.Exit(2) //nolint:mnd
+	}
+
+	return parameters
+}

internal/icinga2/messages.go

@@ -0,0 +1,149 @@
+// Copyright Jan Dittberner
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+package icinga2
+
+import (
+	"fmt"
+	"strings"
+)
+
+const (
+	WarnIcon     = "⚠"
+	ErrorIcon    = "❌"
+	OKIcon       = "🆗"
+	QuestionIcon = "❓"
+)
+
+func getIcon(state string) string {
+	switch state {
+	case "UP", "OK":
+		return OKIcon
+	case "UNKNOWN":
+		return QuestionIcon
+	case "WARNING":
+		return WarnIcon
+	default:
+		return ErrorIcon
+	}
+}
+
+type CouldNotWriteToBufferErr struct {
+	Wrapped error
+}
+
+func (e CouldNotWriteToBufferErr) Error() string {
+	return fmt.Sprintf("could not write to message builder: %s", e.Wrapped)
+}
+
+func (e CouldNotWriteToBufferErr) Unwrap() error {
+	return e.Wrapped
+}
+
+func addOptionalData(message *strings.Builder, p *BaseParameters) error {
+	if p.HostAddress != "" {
+		if _, err := fmt.Fprintf(message, "<strong>IPv4:</strong> %s<br/>\n", p.HostAddress); err != nil {
+			return CouldNotWriteToBufferErr{err}
+		}
+	}
+
+	if p.HostAddress6 != "" {
+		if _, err := fmt.Fprintf(message, "<strong>IPv6:</strong> %s<br/>\n", p.HostAddress6); err != nil {
+			return CouldNotWriteToBufferErr{err}
+		}
+	}
+
+	if p.NotificationAuthorName != "" && p.NotificationComment != "" {
+		if _, err := fmt.Fprintf(
+			message,
+			"Comment by <strong>%s:</strong> %s<br/>\n",
+			p.NotificationAuthorName,
+			p.NotificationComment,
+		); err != nil {
+			return CouldNotWriteToBufferErr{err}
+		}
+	}
+
+	return nil
+}
+
+func BuildHostNotification(p *HostParameters) (string, error) {
+	message := &strings.Builder{}
+
+	if _, err := fmt.Fprintf(
+		message,
+		"%s <strong>HOST:</strong> %s is <strong>%s!</strong><br/>\n"+
+			"<strong>When:</strong> %s<br/>\n"+
+			"<strong>Info:</strong> %s<br/>\n",
+		getIcon(p.HostState),
+		p.HostDisplayName, p.HostState,
+		p.LongDateTime, p.HostOutput); err != nil {
+		return "", CouldNotWriteToBufferErr{err}
+	}
+
+	if err := addOptionalData(message, &p.BaseParameters); err != nil {
+		return "", err
+	}
+
+	if p.IcingaWeb2URL.URL != nil {
+		icinga2Url := p.IcingaWeb2URL.URL.JoinPath("monitoring/host/show")
+
+		q := icinga2Url.Query()
+		q.Set("host", p.Hostname)
+
+		icinga2Url.RawQuery = q.Encode()
+
+		if _, err := message.WriteString(icinga2Url.String()); err != nil {
+			return "", CouldNotWriteToBufferErr{err}
+		}
+	}
+
+	return message.String(), nil
+}
+
+func BuildServiceNotification(p *ServiceParameters) (string, error) {
+	message := &strings.Builder{}
+
+	if _, err := fmt.Fprintf(
+		message,
+		"%s <strong>Service:</strong> %s on %s is <strong>%s</strong>.<br/>\n"+
+			"<strong>When:</strong> %s<br/>\n"+
+			"<strong>Info:</strong> %s<br/>\n",
+		getIcon(p.ServiceState), p.ServiceDisplayName, p.HostDisplayName,
+		p.ServiceState, p.LongDateTime, p.ServiceOutput,
+	); err != nil {
+		return "", CouldNotWriteToBufferErr{err}
+	}
+
+	if err := addOptionalData(message, &p.BaseParameters); err != nil {
+		return "", err
+	}
+
+	if p.IcingaWeb2URL.URL != nil {
+		icinga2Url := p.IcingaWeb2URL.URL.JoinPath("monitoring/service/show")
+
+		q := icinga2Url.Query()
+		q.Set("host", p.Hostname)
+		q.Set("service", p.ServiceName)
+
+		icinga2Url.RawQuery = q.Encode()
+
+		if _, err := message.WriteString(icinga2Url.String()); err != nil {
+			return "", CouldNotWriteToBufferErr{err}
+		}
+	}
+
+	return message.String(), nil
+}

internal/icinga2/parameters.go

@@ -0,0 +1,104 @@
+// Copyright Jan Dittberner
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+package icinga2
+
+import (
+	"errors"
+	"fmt"
+	"net/url"
+)
+
+type URLValue struct {
+	URL *url.URL
+}
+
+func (u *URLValue) Set(value string) error {
+	var err error
+
+	u.URL, err = url.Parse(value)
+	if err != nil {
+		return fmt.Errorf("could not parse URL: %w", err)
+	}
+
+	return nil
+}
+
+func (u *URLValue) String() string {
+	if u.URL != nil {
+		return u.URL.String()
+	}
+
+	return ""
+}
+
+type MatrixParameters struct {
+	MatrixRoom   string
+	MatrixServer URLValue
+	MatrixToken  string
+}
+
+func (m *MatrixParameters) HasRequired() bool {
+	return m.MatrixRoom != "" && m.MatrixServer.URL != nil && m.MatrixToken != ""
+}
+
+type BaseParameters struct {
+	NotificationAuthorName string
+	NotificationComment    string
+	IcingaWeb2URL          URLValue
+	LongDateTime           string
+	Hostname               string
+	HostDisplayName        string
+	HostAddress            string
+	HostAddress6           string
+}
+
+func (p BaseParameters) HasRequired() bool {
+	return p.LongDateTime != "" && p.Hostname != "" && p.HostDisplayName != ""
+}
+
+type HostParameters struct {
+	HostOutput string
+	HostState  string
+	BaseParameters
+	MatrixParameters
+}
+
+func (p *HostParameters) ValidateRequired() error {
+	if !p.BaseParameters.HasRequired() || !p.MatrixParameters.HasRequired() ||
+		p.HostOutput == "" || p.HostState == "" {
+		return errors.New("missing required fields")
+	}
+
+	return nil
+}
+
+type ServiceParameters struct {
+	ServiceName        string
+	ServiceDisplayName string
+	ServiceOutput      string
+	ServiceState       string
+	BaseParameters
+	MatrixParameters
+}
+
+func (p *ServiceParameters) ValidateRequired() error {
+	if !p.BaseParameters.HasRequired() || !p.MatrixParameters.HasRequired() ||
+		p.ServiceName == "" || p.ServiceDisplayName == "" || p.ServiceState == "" || p.ServiceOutput == "" {
+		return errors.New("missing required fields")
+	}
+
+	return nil
+}

internal/matrix/constants.go

@@ -0,0 +1,21 @@
+// Copyright Jan Dittberner
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+package matrix
+
+const (
+	TextMessage = "m.text"
+	HTMLFormat  = "org.matrix.custom.html"
+)

internal/matrix/message.go

@@ -0,0 +1,95 @@
+// Copyright Jan Dittberner
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+package matrix
+
+import (
+	"bytes"
+	"crypto/rand"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+)
+
+const transactionIDLength = 16
+
+type Message struct {
+	Type          string `json:"msgtype"`
+	Body          string `json:"body"`
+	FormattedBody string `json:"formatted_body"`
+	Format        string `json:"format"`
+}
+
+func SendMessage(server *url.URL, room string, token string, message string) error {
+	messageBytes, err := json.Marshal(Message{
+		Type:          TextMessage,
+		Body:          message,
+		FormattedBody: message,
+		Format:        HTMLFormat,
+	})
+	if err != nil {
+		return fmt.Errorf("could not build JSON message: %w", err)
+	}
+
+	transaction, err := generateTransactionID()
+	if err != nil {
+		return err
+	}
+
+	postURL := server.JoinPath("/_matrix/client/r0/rooms/", room, "/send/m.room.message/", transaction)
+
+	request, err := http.NewRequest(http.MethodPut, postURL.String(), bytes.NewBuffer(messageBytes))
+	if err != nil {
+		return fmt.Errorf("could not build request: %w", err)
+	}
+
+	request.Header.Set("Accept", "application/json")
+	request.Header.Set("Content-Type", "application/json")
+	request.Header.Set("Authorization", "Bearer "+token)
+
+	response, err := http.DefaultClient.Do(request)
+	if err != nil {
+		return fmt.Errorf("could not send request: %w", err)
+	}
+
+	defer func() {
+		_ = response.Body.Close()
+	}()
+
+	if response.StatusCode > http.StatusBadRequest {
+		responseBody, err := io.ReadAll(response.Body)
+		if err != nil {
+			return fmt.Errorf("received an error: %s, could not read response body: %w", response.Status, err)
+		}
+
+		return fmt.Errorf("received an error: %s %s", response.Status, string(responseBody))
+	}
+
+	return nil
+}
+
+func generateTransactionID() (string, error) {
+	IDBytes := make([]byte, transactionIDLength)
+
+	_, err := rand.Read(IDBytes)
+	if err != nil {
+		return "", fmt.Errorf("could not generate transaction id: %w", err)
+	}
+
+	return base64.RawURLEncoding.EncodeToString(IDBytes), nil
+}