| 1 | // Package matterhook provides interaction with mattermost incoming/outgoing webhooks |
| 2 | package matterhook |
| 3 | |
| 4 | import ( |
| 5 | "bytes" |
| 6 | "crypto/tls" |
| 7 | "encoding/json" |
| 8 | "fmt" |
| 9 | "io" |
| 10 | "log" |
| 11 | "net" |
| 12 | "net/http" |
| 13 | "time" |
| 14 | |
| 15 | "github.com/gorilla/schema" |
| 16 | "github.com/slack-go/slack" |
| 17 | ) |
| 18 | |
| 19 | // OMessage for mattermost incoming webhook. (send to mattermost) |
| 20 | type OMessage struct { |
| 21 | Channel string `json:"channel,omitempty"` |
| 22 | IconURL string `json:"icon_url,omitempty"` |
| 23 | IconEmoji string `json:"icon_emoji,omitempty"` |
| 24 | UserName string `json:"username,omitempty"` |
| 25 | Text string `json:"text"` |
| 26 | Attachments []slack.Attachment `json:"attachments,omitempty"` |
| 27 | Type string `json:"type,omitempty"` |
| 28 | Props map[string]interface{} `json:"props"` |
| 29 | } |
| 30 | |
| 31 | // IMessage for mattermost outgoing webhook. (received from mattermost) |
| 32 | type IMessage struct { |
| 33 | BotID string `schema:"bot_id"` |
| 34 | BotName string `schema:"bot_name"` |
| 35 | Token string `schema:"token"` |
| 36 | TeamID string `schema:"team_id"` |
| 37 | TeamDomain string `schema:"team_domain"` |
| 38 | ChannelID string `schema:"channel_id"` |
| 39 | ChannelName string `schema:"channel_name"` |
| 40 | Timestamp string `schema:"timestamp"` |
| 41 | UserID string `schema:"user_id"` |
| 42 | UserName string `schema:"user_name"` |
| 43 | PostId string `schema:"post_id"` |
| 44 | RawText string `schema:"raw_text"` |
| 45 | ServiceId string `schema:"service_id"` |
| 46 | Text string `schema:"text"` |
| 47 | TriggerWord string `schema:"trigger_word"` |
| 48 | FileIDs string `schema:"file_ids"` |
| 49 | } |
| 50 | |
| 51 | // Client for Mattermost. |
| 52 | type Client struct { |
| 53 | // URL for incoming webhooks on mattermost. |
| 54 | Url string |
| 55 | In chan IMessage |
| 56 | Out chan OMessage |
| 57 | httpclient *http.Client |
| 58 | Config |
| 59 | } |
| 60 | |
| 61 | // Config for client. |
| 62 | type Config struct { |
| 63 | BindAddress string // Address to listen on |
| 64 | Token string // Only allow this token from Mattermost. (Allow everything when empty) |
| 65 | InsecureSkipVerify bool // disable certificate checking |
| 66 | DisableServer bool // Do not start server for outgoing webhooks from Mattermost. |
| 67 | } |
| 68 | |
| 69 | // New Mattermost client. |
| 70 | func New(url string, config Config) *Client { |
| 71 | c := &Client{Url: url, In: make(chan IMessage), Out: make(chan OMessage), Config: config} |
| 72 | tr := &http.Transport{ |
| 73 | TLSClientConfig: &tls.Config{InsecureSkipVerify: config.InsecureSkipVerify}, //nolint:gosec |
| 74 | } |
| 75 | c.httpclient = &http.Client{Transport: tr} |
| 76 | if !c.DisableServer { |
| 77 | _, _, err := net.SplitHostPort(c.BindAddress) |
| 78 | if err != nil { |
| 79 | log.Fatalf("incorrect bindaddress %s", c.BindAddress) |
| 80 | } |
| 81 | go c.StartServer() |
| 82 | } |
| 83 | return c |
| 84 | } |
| 85 | |
| 86 | // StartServer starts a webserver listening for incoming mattermost POSTS. |
| 87 | func (c *Client) StartServer() { |
| 88 | mux := http.NewServeMux() |
| 89 | mux.Handle("/", c) |
| 90 | srv := &http.Server{ |
| 91 | ReadTimeout: 5 * time.Second, |
| 92 | WriteTimeout: 10 * time.Second, |
| 93 | Handler: mux, |
| 94 | Addr: c.BindAddress, |
| 95 | } |
| 96 | log.Printf("Listening on http://%v...\n", c.BindAddress) |
| 97 | if err := srv.ListenAndServe(); err != nil { |
| 98 | log.Fatal(err) |
| 99 | } |
| 100 | } |
| 101 | |
| 102 | // ServeHTTP implementation. |
| 103 | func (c *Client) ServeHTTP(w http.ResponseWriter, r *http.Request) { |
| 104 | if r.Method != "POST" { |
| 105 | log.Println("invalid " + r.Method + " connection from " + r.RemoteAddr) |
| 106 | http.NotFound(w, r) |
| 107 | return |
| 108 | } |
| 109 | msg := IMessage{} |
| 110 | err := r.ParseForm() |
| 111 | if err != nil { |
| 112 | log.Println(err) |
| 113 | http.NotFound(w, r) |
| 114 | return |
| 115 | } |
| 116 | defer r.Body.Close() |
| 117 | decoder := schema.NewDecoder() |
| 118 | err = decoder.Decode(&msg, r.PostForm) |
| 119 | if err != nil { |
| 120 | log.Println(err) |
| 121 | http.NotFound(w, r) |
| 122 | return |
| 123 | } |
| 124 | if msg.Token == "" { |
| 125 | log.Println("no token from " + r.RemoteAddr) |
| 126 | http.NotFound(w, r) |
| 127 | return |
| 128 | } |
| 129 | if c.Token != "" { |
| 130 | if msg.Token != c.Token { |
| 131 | log.Println("invalid token " + msg.Token + " from " + r.RemoteAddr) |
| 132 | http.NotFound(w, r) |
| 133 | return |
| 134 | } |
| 135 | } |
| 136 | c.In <- msg |
| 137 | } |
| 138 | |
| 139 | // Receive returns an incoming message from mattermost outgoing webhooks URL. |
| 140 | func (c *Client) Receive() IMessage { |
| 141 | var msg IMessage |
| 142 | for msg := range c.In { |
| 143 | return msg |
| 144 | } |
| 145 | return msg |
| 146 | } |
| 147 | |
| 148 | // Send sends a msg to mattermost incoming webhooks URL. |
| 149 | func (c *Client) Send(msg OMessage) error { |
| 150 | buf, err := json.Marshal(msg) |
| 151 | if err != nil { |
| 152 | return err |
| 153 | } |
| 154 | resp, err := c.httpclient.Post(c.Url, "application/json", bytes.NewReader(buf)) |
| 155 | if err != nil { |
| 156 | return err |
| 157 | } |
| 158 | defer resp.Body.Close() |
| 159 | |
| 160 | // Read entire body to completion to re-use keep-alive connections. |
| 161 | _, err = io.Copy(io.Discard, resp.Body) |
| 162 | if err != nil { |
| 163 | return err |
| 164 | } |
| 165 | |
| 166 | if resp.StatusCode != 200 { |
| 167 | return fmt.Errorf("unexpected status code: %d", resp.StatusCode) |
| 168 | } |
| 169 | return nil |
| 170 | } |
| 171 | |
