From c2f2910a838e8a359bba6c2f3c872b2f884db697 Mon Sep 17 00:00:00 2001
From: Pierre-Olivier Mercier <nemunaire@nemunai.re>
Date: Wed, 14 Sep 2022 00:19:43 +0200
Subject: [PATCH] Fetch PGP keys from GitLab CRI as fallback

---
 gitlab.go | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++---
 keys.go   | 15 ++++++++--
 2 files changed, 90 insertions(+), 7 deletions(-)

diff --git a/gitlab.go b/gitlab.go
index 54f3db6..9afeec5 100644
--- a/gitlab.go
+++ b/gitlab.go
@@ -1,13 +1,16 @@
 package main
 
 import (
+	"bytes"
 	"context"
 	"encoding/hex"
 	"encoding/json"
 	"flag"
 	"fmt"
+	"io/ioutil"
 	"log"
 	"net/http"
+	"net/url"
 	"os"
 	"time"
 
@@ -157,13 +160,18 @@ type GitLabRepositoryNamespace struct {
 	Kind string
 }
 
-type GitLabRepositoryUser struct {
+type GitLabUser struct {
 	ID       int
 	Username string
 	Name     string
 	State    string
 }
 
+type GitLabUserKey struct {
+	ID  int
+	Key string
+}
+
 type GitLabRepository struct {
 	ID                int
 	Description       string
@@ -177,9 +185,9 @@ type GitLabRepository struct {
 	AvatarURL         string    `json:"avatar_url"`
 	LastActivityAt    time.Time `json:"last_activity_at,omitempty"`
 	Namespace         GitLabRepositoryNamespace
-	Visibility        string                `json:"visibility,omitempty"`
-	Owner             *GitLabRepositoryUser `json:"owner,omitempty"`
-	ForkedFromProject *GitLabRepository     `json:"forked_from_project,omitempty"`
+	Visibility        string            `json:"visibility,omitempty"`
+	Owner             *GitLabUser       `json:"owner,omitempty"`
+	ForkedFromProject *GitLabRepository `json:"forked_from_project,omitempty"`
 }
 
 func GitLab_GetMyRepositories(c *gin.Context) {
@@ -251,3 +259,69 @@ func GitLab_getUsersRepositories(c context.Context, u *User) ([]*GitLabRepositor
 
 	return repositories, err
 }
+
+func GitLab_getUserId(c context.Context, u *User) (int, error) {
+	client := gitlaboauth2Config.Client(c, gitlabToken())
+
+	val := url.Values{}
+	val.Set("username", u.Login)
+
+	req, err := http.NewRequest("GET", gitlabBaseURL+fmt.Sprintf("/api/v4/users?%s", val.Encode()), nil)
+	if err != nil {
+		return 0, err
+	}
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return 0, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return 0, fmt.Errorf("Bad status code from the API")
+	}
+
+	var users []*GitLabUser
+	err = json.NewDecoder(resp.Body).Decode(&users)
+
+	if len(users) == 0 {
+		return 0, fmt.Errorf("Login not found in GitLab")
+	}
+
+	return users[0].ID, nil
+}
+
+func GitLab_getUserPGPKeys(c context.Context, u *User) ([]byte, error) {
+	userid, err := GitLab_getUserId(c, u)
+	if err != nil {
+		return nil, err
+	}
+
+	client := gitlaboauth2Config.Client(c, gitlabToken())
+
+	req, err := http.NewRequest("GET", gitlabBaseURL+fmt.Sprintf("/api/v4/users/%d/gpg_keys", userid), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		rep, _ := ioutil.ReadAll(resp.Body)
+		log.Printf("%d %s", resp.StatusCode, rep)
+		return nil, fmt.Errorf("Bad status code from the API")
+	}
+
+	var keys []*GitLabUserKey
+	err = json.NewDecoder(resp.Body).Decode(&keys)
+
+	var b bytes.Buffer
+	for _, k := range keys {
+		b.Write([]byte(k.Key))
+		b.Write([]byte{'\n'})
+	}
+
+	return b.Bytes(), nil
+}
diff --git a/keys.go b/keys.go
index 77f9321..e0cf925 100644
--- a/keys.go
+++ b/keys.go
@@ -33,9 +33,18 @@ func declareAPIKeysRoutes(router *gin.RouterGroup) {
 		}
 
 		var ret []byte
-		for _, key := range keys {
-			if key.Type == "pgp" {
-				ret = append(ret, []byte(key.Content)...)
+		if len(keys) == 0 {
+			ret, err = GitLab_getUserPGPKeys(c.Request.Context(), u)
+			if err != nil {
+				log.Println("Unable to GitLab_getUserPGPKeys:", err)
+				c.AbortWithStatusJSON(http.StatusInternalServerError, gin.H{"errmsg": "Unable to retrieve your keys from GitLab. Please try again in a few moment or add them directly on /keys page on this website."})
+				return
+			}
+		} else {
+			for _, key := range keys {
+				if key.Type == "pgp" {
+					ret = append(ret, []byte(key.Content)...)
+				}
 			}
 		}