task_tracker/api/git.go
2019-03-10 09:47:11 -04:00

143 lines
2.9 KiB
Go

package api
import (
"crypto"
"crypto/hmac"
"encoding/hex"
"encoding/json"
"fmt"
"github.com/simon987/task_tracker/config"
"github.com/simon987/task_tracker/storage"
"github.com/sirupsen/logrus"
"github.com/valyala/fasthttp"
"hash"
"strings"
)
func (api *WebAPI) ReceiveGitWebHook(r *Request) {
payload := &GitPayload{}
err := json.Unmarshal(r.Ctx.Request.Body(), payload)
if err != nil {
r.Ctx.SetStatusCode(400)
return
}
logrus.WithFields(logrus.Fields{
"payload": payload,
}).Info("Received git WebHook")
if !isProductionBranch(payload) {
r.Ctx.SetStatusCode(400)
return
}
project := api.getAssociatedProject(payload)
if project == nil {
r.Ctx.SetStatusCode(400)
return
}
signature, err := api.Database.GetWebhookSecret(project.Id)
if err != nil {
_, _ = fmt.Fprintf(r.Ctx, err.Error())
r.Ctx.SetStatusCode(400)
return
}
if !signatureValid(r, signature) {
logrus.Error("WebHook signature does not match!")
r.Ctx.SetStatusCode(403)
_, _ = fmt.Fprintf(r.Ctx, "Signature does not match")
return
}
version := getVersion(payload)
project.Version = version
err = api.Database.UpdateProject(project)
handleErr(err, r)
}
func signatureValid(r *Request, webhookSignature string) (matches bool) {
signature := parseSignatureFromRequest(r.Ctx)
if signature == "" {
return false
}
body := r.Ctx.PostBody()
mac := hmac.New(getHashFuncFromConfig(), []byte(webhookSignature))
mac.Write(body)
expectedMac := hex.EncodeToString(mac.Sum(nil))
matches = strings.Compare(expectedMac, signature) == 0
logrus.WithFields(logrus.Fields{
"expected": expectedMac,
"signature": signature,
"matches": matches,
}).Trace("Validating WebHook signature")
return
}
func getHashFuncFromConfig() func() hash.Hash {
if config.Cfg.WebHookHash == "sha1" {
return crypto.SHA1.New
} else if config.Cfg.WebHookHash == "sha256" {
return crypto.SHA256.New
}
logrus.WithFields(logrus.Fields{
"hash": config.Cfg.WebHookHash,
}).Error("Invalid hash function from config")
return nil
}
func parseSignatureFromRequest(ctx *fasthttp.RequestCtx) string {
signature := string(ctx.Request.Header.Peek(config.Cfg.WebHookSigHeader))
sigParts := strings.Split(signature, "=")
signature = sigParts[len(sigParts)-1]
return signature
}
func (api *WebAPI) getAssociatedProject(payload *GitPayload) *storage.Project {
project := api.Database.GetProjectWithRepoName(payload.Repository.FullName)
logrus.WithFields(logrus.Fields{
"project": project,
}).Trace("Found project associated with WebHook")
return project
}
func isProductionBranch(payload *GitPayload) (isProd bool) {
isProd = strings.HasSuffix(payload.Ref, "master")
logrus.WithFields(logrus.Fields{
"isProd": isProd,
}).Trace("Identified if push event occured in production branch")
return
}
func getVersion(payload *GitPayload) (version string) {
version = payload.After
logrus.WithFields(logrus.Fields{
"version": version,
}).Trace("Got new version")
return
}