vorteil/direktiv

package auth

import (
    "bytes"
    "encoding/json"
    "io"
    "net/http"
    "net/url"

    "github.com/direktiv/direktiv/pkg/core"
    "github.com/direktiv/direktiv/pkg/gateway"
    "github.com/slack-go/slack"
)

type SlackWebhookPlugin struct {
    Secret string `mapstructure:"secret"`
}

func (p *SlackWebhookPlugin) NewInstance(config core.PluginConfig) (core.Plugin, error) {
    pl := &SlackWebhookPlugin{}

    err := gateway.ConvertConfig(config.Config, pl)
    if err != nil {
        return nil, err
    }

    return pl, nil
}

func (p *SlackWebhookPlugin) Execute(w http.ResponseWriter, r *http.Request) *http.Request {
    // check request is already authenticated
    if gateway.ExtractContextActiveConsumer(r) != nil {
        return r
    }

    body, err := io.ReadAll(r.Body)
    if err != nil {
        gateway.WriteInternalError(r, w, err, "can not read request body")
        return nil
    }

    sv, err := slack.NewSecretsVerifier(r.Header, p.Secret)
    if err != nil {
        gateway.WriteInternalError(r, w, err, "can not create slack verifier")
        return nil
    }

    if _, err := sv.Write(body); err != nil {
        gateway.WriteInternalError(r, w, err, "can not write slack hmac")
        return nil
    }

    // hmac is not valid
    if err := sv.Ensure(); err != nil {
        gateway.WriteInternalError(r, w, err, "slack hmac failed")
        return nil
    }

    c := &core.Consumer{
        ConsumerFile: core.ConsumerFile{
            Username: "slack",
        },
    }
    // set active comsumer.
    r = gateway.InjectContextActiveConsumer(r, c)

    // convert to json if url encoded
    // nolint:canonicalheader
    if r.Header.Get("Content-type") == "application/x-www-form-urlencoded" {
        v, err := url.ParseQuery(string(body))
        if err != nil {
            gateway.WriteInternalError(r, w, err, "can parse url form encoded data")
            return nil
        }

        b, err := json.Marshal(v)
        if err != nil {
            gateway.WriteInternalError(r, w, err, "can not marshal slack data")
            return nil
        }
        r.Body = io.NopCloser(bytes.NewBuffer(b))
    } else {
        r.Body = io.NopCloser(bytes.NewBuffer(body))
    }

    return r
}

func (*SlackWebhookPlugin) Type() string {
    return "slack-webhook-auth"
}

func init() {
    gateway.RegisterPlugin(&SlackWebhookPlugin{})
}