auth: add new authentication source: GitHub, including GitHub Enterprise (#5340)

* Add new Authentication Source: GitHub, including GitHub Enterprise.

* Add vendor dependencies.

vendor/github.com/google/go-github/github/users_gpg_keys.go

@@ -0,0 +1,140 @@
+// Copyright 2016 The go-github AUTHORS. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package github
+
+import (
+	"context"
+	"fmt"
+	"time"
+)
+
+// GPGKey represents a GitHub user's public GPG key used to verify GPG signed commits and tags.
+//
+// https://developer.github.com/changes/2016-04-04-git-signing-api-preview/
+type GPGKey struct {
+	ID                *int64     `json:"id,omitempty"`
+	PrimaryKeyID      *int64     `json:"primary_key_id,omitempty"`
+	KeyID             *string    `json:"key_id,omitempty"`
+	PublicKey         *string    `json:"public_key,omitempty"`
+	Emails            []GPGEmail `json:"emails,omitempty"`
+	Subkeys           []GPGKey   `json:"subkeys,omitempty"`
+	CanSign           *bool      `json:"can_sign,omitempty"`
+	CanEncryptComms   *bool      `json:"can_encrypt_comms,omitempty"`
+	CanEncryptStorage *bool      `json:"can_encrypt_storage,omitempty"`
+	CanCertify        *bool      `json:"can_certify,omitempty"`
+	CreatedAt         *time.Time `json:"created_at,omitempty"`
+	ExpiresAt         *time.Time `json:"expires_at,omitempty"`
+}
+
+// String stringifies a GPGKey.
+func (k GPGKey) String() string {
+	return Stringify(k)
+}
+
+// GPGEmail represents an email address associated to a GPG key.
+type GPGEmail struct {
+	Email    *string `json:"email,omitempty"`
+	Verified *bool   `json:"verified,omitempty"`
+}
+
+// ListGPGKeys lists the public GPG keys for a user. Passing the empty
+// string will fetch keys for the authenticated user. It requires authentication
+// via Basic Auth or via OAuth with at least read:gpg_key scope.
+//
+// GitHub API docs: https://developer.github.com/v3/users/gpg_keys/#list-gpg-keys-for-a-user
+func (s *UsersService) ListGPGKeys(ctx context.Context, user string, opt *ListOptions) ([]*GPGKey, *Response, error) {
+	var u string
+	if user != "" {
+		u = fmt.Sprintf("users/%v/gpg_keys", user)
+	} else {
+		u = "user/gpg_keys"
+	}
+	u, err := addOptions(u, opt)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	req, err := s.client.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches.
+	req.Header.Set("Accept", mediaTypeGitSigningPreview)
+
+	var keys []*GPGKey
+	resp, err := s.client.Do(ctx, req, &keys)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return keys, resp, nil
+}
+
+// GetGPGKey gets extended details for a single GPG key. It requires authentication
+// via Basic Auth or via OAuth with at least read:gpg_key scope.
+//
+// GitHub API docs: https://developer.github.com/v3/users/gpg_keys/#get-a-single-gpg-key
+func (s *UsersService) GetGPGKey(ctx context.Context, id int64) (*GPGKey, *Response, error) {
+	u := fmt.Sprintf("user/gpg_keys/%v", id)
+	req, err := s.client.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches.
+	req.Header.Set("Accept", mediaTypeGitSigningPreview)
+
+	key := &GPGKey{}
+	resp, err := s.client.Do(ctx, req, key)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return key, resp, nil
+}
+
+// CreateGPGKey creates a GPG key. It requires authenticatation via Basic Auth
+// or OAuth with at least write:gpg_key scope.
+//
+// GitHub API docs: https://developer.github.com/v3/users/gpg_keys/#create-a-gpg-key
+func (s *UsersService) CreateGPGKey(ctx context.Context, armoredPublicKey string) (*GPGKey, *Response, error) {
+	gpgKey := &struct {
+		ArmoredPublicKey string `json:"armored_public_key"`
+	}{ArmoredPublicKey: armoredPublicKey}
+	req, err := s.client.NewRequest("POST", "user/gpg_keys", gpgKey)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches.
+	req.Header.Set("Accept", mediaTypeGitSigningPreview)
+
+	key := &GPGKey{}
+	resp, err := s.client.Do(ctx, req, key)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return key, resp, nil
+}
+
+// DeleteGPGKey deletes a GPG key. It requires authentication via Basic Auth or
+// via OAuth with at least admin:gpg_key scope.
+//
+// GitHub API docs: https://developer.github.com/v3/users/gpg_keys/#delete-a-gpg-key
+func (s *UsersService) DeleteGPGKey(ctx context.Context, id int64) (*Response, error) {
+	u := fmt.Sprintf("user/gpg_keys/%v", id)
+	req, err := s.client.NewRequest("DELETE", u, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches.
+	req.Header.Set("Accept", mediaTypeGitSigningPreview)
+
+	return s.client.Do(ctx, req, nil)
+}