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

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

* Add vendor dependencies.

1 files changed, 1051 insertions, 0 deletions

diff --git a/vendor/github.com/google/go-github/github/repos.go b/vendor/github.com/google/go-github/github/repos.go
new file mode 100644
index 00000000..aa9b6ace
--- /dev/null
+++ b/vendor/github.com/google/go-github/github/repos.go
@@ -0,0 +1,1051 @@
+// Copyright 2013 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"
+	"strings"
+)
+
+// RepositoriesService handles communication with the repository related
+// methods of the GitHub API.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/
+type RepositoriesService service
+
+// Repository represents a GitHub repository.
+type Repository struct {
+	ID               *int64           `json:"id,omitempty"`
+	Owner            *User            `json:"owner,omitempty"`
+	Name             *string          `json:"name,omitempty"`
+	FullName         *string          `json:"full_name,omitempty"`
+	Description      *string          `json:"description,omitempty"`
+	Homepage         *string          `json:"homepage,omitempty"`
+	CodeOfConduct    *CodeOfConduct   `json:"code_of_conduct,omitempty"`
+	DefaultBranch    *string          `json:"default_branch,omitempty"`
+	MasterBranch     *string          `json:"master_branch,omitempty"`
+	CreatedAt        *Timestamp       `json:"created_at,omitempty"`
+	PushedAt         *Timestamp       `json:"pushed_at,omitempty"`
+	UpdatedAt        *Timestamp       `json:"updated_at,omitempty"`
+	HTMLURL          *string          `json:"html_url,omitempty"`
+	CloneURL         *string          `json:"clone_url,omitempty"`
+	GitURL           *string          `json:"git_url,omitempty"`
+	MirrorURL        *string          `json:"mirror_url,omitempty"`
+	SSHURL           *string          `json:"ssh_url,omitempty"`
+	SVNURL           *string          `json:"svn_url,omitempty"`
+	Language         *string          `json:"language,omitempty"`
+	Fork             *bool            `json:"fork,omitempty"`
+	ForksCount       *int             `json:"forks_count,omitempty"`
+	NetworkCount     *int             `json:"network_count,omitempty"`
+	OpenIssuesCount  *int             `json:"open_issues_count,omitempty"`
+	StargazersCount  *int             `json:"stargazers_count,omitempty"`
+	SubscribersCount *int             `json:"subscribers_count,omitempty"`
+	WatchersCount    *int             `json:"watchers_count,omitempty"`
+	Size             *int             `json:"size,omitempty"`
+	AutoInit         *bool            `json:"auto_init,omitempty"`
+	Parent           *Repository      `json:"parent,omitempty"`
+	Source           *Repository      `json:"source,omitempty"`
+	Organization     *Organization    `json:"organization,omitempty"`
+	Permissions      *map[string]bool `json:"permissions,omitempty"`
+	AllowRebaseMerge *bool            `json:"allow_rebase_merge,omitempty"`
+	AllowSquashMerge *bool            `json:"allow_squash_merge,omitempty"`
+	AllowMergeCommit *bool            `json:"allow_merge_commit,omitempty"`
+	Topics           []string         `json:"topics,omitempty"`
+
+	// Only provided when using RepositoriesService.Get while in preview
+	License *License `json:"license,omitempty"`
+
+	// Additional mutable fields when creating and editing a repository
+	Private           *bool   `json:"private,omitempty"`
+	HasIssues         *bool   `json:"has_issues,omitempty"`
+	HasWiki           *bool   `json:"has_wiki,omitempty"`
+	HasPages          *bool   `json:"has_pages,omitempty"`
+	HasProjects       *bool   `json:"has_projects,omitempty"`
+	HasDownloads      *bool   `json:"has_downloads,omitempty"`
+	LicenseTemplate   *string `json:"license_template,omitempty"`
+	GitignoreTemplate *string `json:"gitignore_template,omitempty"`
+	Archived          *bool   `json:"archived,omitempty"`
+
+	// Creating an organization repository. Required for non-owners.
+	TeamID *int64 `json:"team_id,omitempty"`
+
+	// API URLs
+	URL              *string `json:"url,omitempty"`
+	ArchiveURL       *string `json:"archive_url,omitempty"`
+	AssigneesURL     *string `json:"assignees_url,omitempty"`
+	BlobsURL         *string `json:"blobs_url,omitempty"`
+	BranchesURL      *string `json:"branches_url,omitempty"`
+	CollaboratorsURL *string `json:"collaborators_url,omitempty"`
+	CommentsURL      *string `json:"comments_url,omitempty"`
+	CommitsURL       *string `json:"commits_url,omitempty"`
+	CompareURL       *string `json:"compare_url,omitempty"`
+	ContentsURL      *string `json:"contents_url,omitempty"`
+	ContributorsURL  *string `json:"contributors_url,omitempty"`
+	DeploymentsURL   *string `json:"deployments_url,omitempty"`
+	DownloadsURL     *string `json:"downloads_url,omitempty"`
+	EventsURL        *string `json:"events_url,omitempty"`
+	ForksURL         *string `json:"forks_url,omitempty"`
+	GitCommitsURL    *string `json:"git_commits_url,omitempty"`
+	GitRefsURL       *string `json:"git_refs_url,omitempty"`
+	GitTagsURL       *string `json:"git_tags_url,omitempty"`
+	HooksURL         *string `json:"hooks_url,omitempty"`
+	IssueCommentURL  *string `json:"issue_comment_url,omitempty"`
+	IssueEventsURL   *string `json:"issue_events_url,omitempty"`
+	IssuesURL        *string `json:"issues_url,omitempty"`
+	KeysURL          *string `json:"keys_url,omitempty"`
+	LabelsURL        *string `json:"labels_url,omitempty"`
+	LanguagesURL     *string `json:"languages_url,omitempty"`
+	MergesURL        *string `json:"merges_url,omitempty"`
+	MilestonesURL    *string `json:"milestones_url,omitempty"`
+	NotificationsURL *string `json:"notifications_url,omitempty"`
+	PullsURL         *string `json:"pulls_url,omitempty"`
+	ReleasesURL      *string `json:"releases_url,omitempty"`
+	StargazersURL    *string `json:"stargazers_url,omitempty"`
+	StatusesURL      *string `json:"statuses_url,omitempty"`
+	SubscribersURL   *string `json:"subscribers_url,omitempty"`
+	SubscriptionURL  *string `json:"subscription_url,omitempty"`
+	TagsURL          *string `json:"tags_url,omitempty"`
+	TreesURL         *string `json:"trees_url,omitempty"`
+	TeamsURL         *string `json:"teams_url,omitempty"`
+
+	// TextMatches is only populated from search results that request text matches
+	// See: search.go and https://developer.github.com/v3/search/#text-match-metadata
+	TextMatches []TextMatch `json:"text_matches,omitempty"`
+}
+
+func (r Repository) String() string {
+	return Stringify(r)
+}
+
+// RepositoryListOptions specifies the optional parameters to the
+// RepositoriesService.List method.
+type RepositoryListOptions struct {
+	// Visibility of repositories to list. Can be one of all, public, or private.
+	// Default: all
+	Visibility string `url:"visibility,omitempty"`
+
+	// List repos of given affiliation[s].
+	// Comma-separated list of values. Can include:
+	// * owner: Repositories that are owned by the authenticated user.
+	// * collaborator: Repositories that the user has been added to as a
+	//   collaborator.
+	// * organization_member: Repositories that the user has access to through
+	//   being a member of an organization. This includes every repository on
+	//   every team that the user is on.
+	// Default: owner,collaborator,organization_member
+	Affiliation string `url:"affiliation,omitempty"`
+
+	// Type of repositories to list.
+	// Can be one of all, owner, public, private, member. Default: all
+	// Will cause a 422 error if used in the same request as visibility or
+	// affiliation.
+	Type string `url:"type,omitempty"`
+
+	// How to sort the repository list. Can be one of created, updated, pushed,
+	// full_name. Default: full_name
+	Sort string `url:"sort,omitempty"`
+
+	// Direction in which to sort repositories. Can be one of asc or desc.
+	// Default: when using full_name: asc; otherwise desc
+	Direction string `url:"direction,omitempty"`
+
+	ListOptions
+}
+
+// List the repositories for a user. Passing the empty string will list
+// repositories for the authenticated user.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#list-user-repositories
+func (s *RepositoriesService) List(ctx context.Context, user string, opt *RepositoryListOptions) ([]*Repository, *Response, error) {
+	var u string
+	if user != "" {
+		u = fmt.Sprintf("users/%v/repos", user)
+	} else {
+		u = "user/repos"
+	}
+	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 headers when APIs fully launch.
+	acceptHeaders := []string{mediaTypeLicensesPreview, mediaTypeCodesOfConductPreview, mediaTypeTopicsPreview}
+	req.Header.Set("Accept", strings.Join(acceptHeaders, ", "))
+
+	var repos []*Repository
+	resp, err := s.client.Do(ctx, req, &repos)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return repos, resp, nil
+}
+
+// RepositoryListByOrgOptions specifies the optional parameters to the
+// RepositoriesService.ListByOrg method.
+type RepositoryListByOrgOptions struct {
+	// Type of repositories to list. Possible values are: all, public, private,
+	// forks, sources, member. Default is "all".
+	Type string `url:"type,omitempty"`
+
+	ListOptions
+}
+
+// ListByOrg lists the repositories for an organization.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#list-organization-repositories
+func (s *RepositoriesService) ListByOrg(ctx context.Context, org string, opt *RepositoryListByOrgOptions) ([]*Repository, *Response, error) {
+	u := fmt.Sprintf("orgs/%v/repos", org)
+	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 headers when APIs fully launch.
+	acceptHeaders := []string{mediaTypeLicensesPreview, mediaTypeCodesOfConductPreview, mediaTypeTopicsPreview}
+	req.Header.Set("Accept", strings.Join(acceptHeaders, ", "))
+
+	var repos []*Repository
+	resp, err := s.client.Do(ctx, req, &repos)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return repos, resp, nil
+}
+
+// RepositoryListAllOptions specifies the optional parameters to the
+// RepositoriesService.ListAll method.
+type RepositoryListAllOptions struct {
+	// ID of the last repository seen
+	Since int64 `url:"since,omitempty"`
+}
+
+// ListAll lists all GitHub repositories in the order that they were created.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#list-all-public-repositories
+func (s *RepositoriesService) ListAll(ctx context.Context, opt *RepositoryListAllOptions) ([]*Repository, *Response, error) {
+	u, err := addOptions("repositories", opt)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	req, err := s.client.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	var repos []*Repository
+	resp, err := s.client.Do(ctx, req, &repos)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return repos, resp, nil
+}
+
+// Create a new repository. If an organization is specified, the new
+// repository will be created under that org. If the empty string is
+// specified, it will be created for the authenticated user.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#create
+func (s *RepositoriesService) Create(ctx context.Context, org string, repo *Repository) (*Repository, *Response, error) {
+	var u string
+	if org != "" {
+		u = fmt.Sprintf("orgs/%v/repos", org)
+	} else {
+		u = "user/repos"
+	}
+
+	req, err := s.client.NewRequest("POST", u, repo)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	r := new(Repository)
+	resp, err := s.client.Do(ctx, req, r)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return r, resp, nil
+}
+
+// Get fetches a repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#get
+func (s *RepositoriesService) Get(ctx context.Context, owner, repo string) (*Repository, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v", owner, repo)
+	req, err := s.client.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when the license support fully launches
+	// https://developer.github.com/v3/licenses/#get-a-repositorys-license
+	acceptHeaders := []string{mediaTypeLicensesPreview, mediaTypeCodesOfConductPreview, mediaTypeTopicsPreview}
+	req.Header.Set("Accept", strings.Join(acceptHeaders, ", "))
+
+	repository := new(Repository)
+	resp, err := s.client.Do(ctx, req, repository)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return repository, resp, nil
+}
+
+// GetCodeOfConduct gets the contents of a repository's code of conduct.
+//
+// GitHub API docs: https://developer.github.com/v3/codes_of_conduct/#get-the-contents-of-a-repositorys-code-of-conduct
+func (s *RepositoriesService) GetCodeOfConduct(ctx context.Context, owner, repo string) (*CodeOfConduct, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/community/code_of_conduct", owner, repo)
+	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", mediaTypeCodesOfConductPreview)
+
+	coc := new(CodeOfConduct)
+	resp, err := s.client.Do(ctx, req, coc)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return coc, resp, nil
+}
+
+// GetByID fetches a repository.
+//
+// Note: GetByID uses the undocumented GitHub API endpoint /repositories/:id.
+func (s *RepositoriesService) GetByID(ctx context.Context, id int64) (*Repository, *Response, error) {
+	u := fmt.Sprintf("repositories/%d", id)
+	req, err := s.client.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when the license support fully launches
+	// https://developer.github.com/v3/licenses/#get-a-repositorys-license
+	req.Header.Set("Accept", mediaTypeLicensesPreview)
+
+	repository := new(Repository)
+	resp, err := s.client.Do(ctx, req, repository)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return repository, resp, nil
+}
+
+// Edit updates a repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#edit
+func (s *RepositoriesService) Edit(ctx context.Context, owner, repo string, repository *Repository) (*Repository, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v", owner, repo)
+	req, err := s.client.NewRequest("PATCH", u, repository)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	r := new(Repository)
+	resp, err := s.client.Do(ctx, req, r)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return r, resp, nil
+}
+
+// Delete a repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#delete-a-repository
+func (s *RepositoriesService) Delete(ctx context.Context, owner, repo string) (*Response, error) {
+	u := fmt.Sprintf("repos/%v/%v", owner, repo)
+	req, err := s.client.NewRequest("DELETE", u, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	return s.client.Do(ctx, req, nil)
+}
+
+// Contributor represents a repository contributor
+type Contributor struct {
+	Login             *string `json:"login,omitempty"`
+	ID                *int64  `json:"id,omitempty"`
+	AvatarURL         *string `json:"avatar_url,omitempty"`
+	GravatarID        *string `json:"gravatar_id,omitempty"`
+	URL               *string `json:"url,omitempty"`
+	HTMLURL           *string `json:"html_url,omitempty"`
+	FollowersURL      *string `json:"followers_url,omitempty"`
+	FollowingURL      *string `json:"following_url,omitempty"`
+	GistsURL          *string `json:"gists_url,omitempty"`
+	StarredURL        *string `json:"starred_url,omitempty"`
+	SubscriptionsURL  *string `json:"subscriptions_url,omitempty"`
+	OrganizationsURL  *string `json:"organizations_url,omitempty"`
+	ReposURL          *string `json:"repos_url,omitempty"`
+	EventsURL         *string `json:"events_url,omitempty"`
+	ReceivedEventsURL *string `json:"received_events_url,omitempty"`
+	Type              *string `json:"type,omitempty"`
+	SiteAdmin         *bool   `json:"site_admin,omitempty"`
+	Contributions     *int    `json:"contributions,omitempty"`
+}
+
+// ListContributorsOptions specifies the optional parameters to the
+// RepositoriesService.ListContributors method.
+type ListContributorsOptions struct {
+	// Include anonymous contributors in results or not
+	Anon string `url:"anon,omitempty"`
+
+	ListOptions
+}
+
+// ListContributors lists contributors for a repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#list-contributors
+func (s *RepositoriesService) ListContributors(ctx context.Context, owner string, repository string, opt *ListContributorsOptions) ([]*Contributor, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/contributors", owner, repository)
+	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
+	}
+
+	var contributor []*Contributor
+	resp, err := s.client.Do(ctx, req, &contributor)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return contributor, resp, nil
+}
+
+// ListLanguages lists languages for the specified repository. The returned map
+// specifies the languages and the number of bytes of code written in that
+// language. For example:
+//
+//     {
+//       "C": 78769,
+//       "Python": 7769
+//     }
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#list-languages
+func (s *RepositoriesService) ListLanguages(ctx context.Context, owner string, repo string) (map[string]int, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/languages", owner, repo)
+	req, err := s.client.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	languages := make(map[string]int)
+	resp, err := s.client.Do(ctx, req, &languages)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return languages, resp, nil
+}
+
+// ListTeams lists the teams for the specified repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#list-teams
+func (s *RepositoriesService) ListTeams(ctx context.Context, owner string, repo string, opt *ListOptions) ([]*Team, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/teams", owner, repo)
+	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
+	}
+
+	req.Header.Set("Accept", mediaTypeNestedTeamsPreview)
+
+	var teams []*Team
+	resp, err := s.client.Do(ctx, req, &teams)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return teams, resp, nil
+}
+
+// RepositoryTag represents a repository tag.
+type RepositoryTag struct {
+	Name       *string `json:"name,omitempty"`
+	Commit     *Commit `json:"commit,omitempty"`
+	ZipballURL *string `json:"zipball_url,omitempty"`
+	TarballURL *string `json:"tarball_url,omitempty"`
+}
+
+// ListTags lists tags for the specified repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#list-tags
+func (s *RepositoriesService) ListTags(ctx context.Context, owner string, repo string, opt *ListOptions) ([]*RepositoryTag, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/tags", owner, repo)
+	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
+	}
+
+	var tags []*RepositoryTag
+	resp, err := s.client.Do(ctx, req, &tags)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return tags, resp, nil
+}
+
+// Branch represents a repository branch
+type Branch struct {
+	Name      *string           `json:"name,omitempty"`
+	Commit    *RepositoryCommit `json:"commit,omitempty"`
+	Protected *bool             `json:"protected,omitempty"`
+}
+
+// Protection represents a repository branch's protection.
+type Protection struct {
+	RequiredStatusChecks       *RequiredStatusChecks          `json:"required_status_checks"`
+	RequiredPullRequestReviews *PullRequestReviewsEnforcement `json:"required_pull_request_reviews"`
+	EnforceAdmins              *AdminEnforcement              `json:"enforce_admins"`
+	Restrictions               *BranchRestrictions            `json:"restrictions"`
+}
+
+// ProtectionRequest represents a request to create/edit a branch's protection.
+type ProtectionRequest struct {
+	RequiredStatusChecks       *RequiredStatusChecks                 `json:"required_status_checks"`
+	RequiredPullRequestReviews *PullRequestReviewsEnforcementRequest `json:"required_pull_request_reviews"`
+	EnforceAdmins              bool                                  `json:"enforce_admins"`
+	Restrictions               *BranchRestrictionsRequest            `json:"restrictions"`
+}
+
+// RequiredStatusChecks represents the protection status of a individual branch.
+type RequiredStatusChecks struct {
+	// Require branches to be up to date before merging. (Required.)
+	Strict bool `json:"strict"`
+	// The list of status checks to require in order to merge into this
+	// branch. (Required; use []string{} instead of nil for empty list.)
+	Contexts []string `json:"contexts"`
+}
+
+// PullRequestReviewsEnforcement represents the pull request reviews enforcement of a protected branch.
+type PullRequestReviewsEnforcement struct {
+	// Specifies which users and teams can dismiss pull request reviews.
+	DismissalRestrictions DismissalRestrictions `json:"dismissal_restrictions"`
+	// Specifies if approved reviews are dismissed automatically, when a new commit is pushed.
+	DismissStaleReviews bool `json:"dismiss_stale_reviews"`
+	// RequireCodeOwnerReviews specifies if an approved review is required in pull requests including files with a designated code owner.
+	RequireCodeOwnerReviews bool `json:"require_code_owner_reviews"`
+}
+
+// PullRequestReviewsEnforcementRequest represents request to set the pull request review
+// enforcement of a protected branch. It is separate from PullRequestReviewsEnforcement above
+// because the request structure is different from the response structure.
+type PullRequestReviewsEnforcementRequest struct {
+	// Specifies which users and teams should be allowed to dismiss pull request reviews.
+	// User and team dismissal restrictions are only available for
+	// organization-owned repositories. Must be nil for personal repositories.
+	DismissalRestrictionsRequest *DismissalRestrictionsRequest `json:"dismissal_restrictions,omitempty"`
+	// Specifies if approved reviews can be dismissed automatically, when a new commit is pushed. (Required)
+	DismissStaleReviews bool `json:"dismiss_stale_reviews"`
+	// RequireCodeOwnerReviews specifies if an approved review is required in pull requests including files with a designated code owner.
+	RequireCodeOwnerReviews bool `json:"require_code_owner_reviews"`
+}
+
+// PullRequestReviewsEnforcementUpdate represents request to patch the pull request review
+// enforcement of a protected branch. It is separate from PullRequestReviewsEnforcementRequest above
+// because the patch request does not require all fields to be initialized.
+type PullRequestReviewsEnforcementUpdate struct {
+	// Specifies which users and teams can dismiss pull request reviews. Can be omitted.
+	DismissalRestrictionsRequest *DismissalRestrictionsRequest `json:"dismissal_restrictions,omitempty"`
+	// Specifies if approved reviews can be dismissed automatically, when a new commit is pushed. Can be omitted.
+	DismissStaleReviews *bool `json:"dismiss_stale_reviews,omitempty"`
+	// RequireCodeOwnerReviews specifies if an approved review is required in pull requests including files with a designated code owner.
+	RequireCodeOwnerReviews bool `json:"require_code_owner_reviews,omitempty"`
+}
+
+// AdminEnforcement represents the configuration to enforce required status checks for repository administrators.
+type AdminEnforcement struct {
+	URL     *string `json:"url,omitempty"`
+	Enabled bool    `json:"enabled"`
+}
+
+// BranchRestrictions represents the restriction that only certain users or
+// teams may push to a branch.
+type BranchRestrictions struct {
+	// The list of user logins with push access.
+	Users []*User `json:"users"`
+	// The list of team slugs with push access.
+	Teams []*Team `json:"teams"`
+}
+
+// BranchRestrictionsRequest represents the request to create/edit the
+// restriction that only certain users or teams may push to a branch. It is
+// separate from BranchRestrictions above because the request structure is
+// different from the response structure.
+type BranchRestrictionsRequest struct {
+	// The list of user logins with push access. (Required; use []string{} instead of nil for empty list.)
+	Users []string `json:"users"`
+	// The list of team slugs with push access. (Required; use []string{} instead of nil for empty list.)
+	Teams []string `json:"teams"`
+}
+
+// DismissalRestrictions specifies which users and teams can dismiss pull request reviews.
+type DismissalRestrictions struct {
+	// The list of users who can dimiss pull request reviews.
+	Users []*User `json:"users"`
+	// The list of teams which can dismiss pull request reviews.
+	Teams []*Team `json:"teams"`
+}
+
+// DismissalRestrictionsRequest represents the request to create/edit the
+// restriction to allows only specific users or teams to dimiss pull request reviews. It is
+// separate from DismissalRestrictions above because the request structure is
+// different from the response structure.
+// Note: Both Users and Teams must be nil, or both must be non-nil.
+type DismissalRestrictionsRequest struct {
+	// The list of user logins who can dismiss pull request reviews. (Required; use nil to disable dismissal_restrictions or &[]string{} otherwise.)
+	Users *[]string `json:"users,omitempty"`
+	// The list of team slugs which can dismiss pull request reviews. (Required; use nil to disable dismissal_restrictions or &[]string{} otherwise.)
+	Teams *[]string `json:"teams,omitempty"`
+}
+
+// ListBranches lists branches for the specified repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#list-branches
+func (s *RepositoriesService) ListBranches(ctx context.Context, owner string, repo string, opt *ListOptions) ([]*Branch, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches", owner, repo)
+	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", mediaTypeProtectedBranchesPreview)
+
+	var branches []*Branch
+	resp, err := s.client.Do(ctx, req, &branches)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return branches, resp, nil
+}
+
+// GetBranch gets the specified branch for a repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#get-branch
+func (s *RepositoriesService) GetBranch(ctx context.Context, owner, repo, branch string) (*Branch, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v", owner, repo, branch)
+	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", mediaTypeProtectedBranchesPreview)
+
+	b := new(Branch)
+	resp, err := s.client.Do(ctx, req, b)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return b, resp, nil
+}
+
+// GetBranchProtection gets the protection of a given branch.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#get-branch-protection
+func (s *RepositoriesService) GetBranchProtection(ctx context.Context, owner, repo, branch string) (*Protection, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection", owner, repo, branch)
+	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", mediaTypeProtectedBranchesPreview)
+
+	p := new(Protection)
+	resp, err := s.client.Do(ctx, req, p)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return p, resp, nil
+}
+
+// GetRequiredStatusChecks gets the required status checks for a given protected branch.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#get-required-status-checks-of-protected-branch
+func (s *RepositoriesService) GetRequiredStatusChecks(ctx context.Context, owner, repo, branch string) (*RequiredStatusChecks, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection/required_status_checks", owner, repo, branch)
+	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", mediaTypeProtectedBranchesPreview)
+
+	p := new(RequiredStatusChecks)
+	resp, err := s.client.Do(ctx, req, p)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return p, resp, nil
+}
+
+// ListRequiredStatusChecksContexts lists the required status checks contexts for a given protected branch.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#list-required-status-checks-contexts-of-protected-branch
+func (s *RepositoriesService) ListRequiredStatusChecksContexts(ctx context.Context, owner, repo, branch string) (contexts []string, resp *Response, err error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection/required_status_checks/contexts", owner, repo, branch)
+	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", mediaTypeProtectedBranchesPreview)
+
+	resp, err = s.client.Do(ctx, req, &contexts)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return contexts, resp, nil
+}
+
+// UpdateBranchProtection updates the protection of a given branch.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#update-branch-protection
+func (s *RepositoriesService) UpdateBranchProtection(ctx context.Context, owner, repo, branch string, preq *ProtectionRequest) (*Protection, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection", owner, repo, branch)
+	req, err := s.client.NewRequest("PUT", u, preq)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches
+	req.Header.Set("Accept", mediaTypeProtectedBranchesPreview)
+
+	p := new(Protection)
+	resp, err := s.client.Do(ctx, req, p)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return p, resp, nil
+}
+
+// RemoveBranchProtection removes the protection of a given branch.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#remove-branch-protection
+func (s *RepositoriesService) RemoveBranchProtection(ctx context.Context, owner, repo, branch string) (*Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection", owner, repo, branch)
+	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", mediaTypeProtectedBranchesPreview)
+
+	return s.client.Do(ctx, req, nil)
+}
+
+// License gets the contents of a repository's license if one is detected.
+//
+// GitHub API docs: https://developer.github.com/v3/licenses/#get-the-contents-of-a-repositorys-license
+func (s *RepositoriesService) License(ctx context.Context, owner, repo string) (*RepositoryLicense, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/license", owner, repo)
+	req, err := s.client.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	r := &RepositoryLicense{}
+	resp, err := s.client.Do(ctx, req, r)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return r, resp, nil
+}
+
+// GetPullRequestReviewEnforcement gets pull request review enforcement of a protected branch.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#get-pull-request-review-enforcement-of-protected-branch
+func (s *RepositoriesService) GetPullRequestReviewEnforcement(ctx context.Context, owner, repo, branch string) (*PullRequestReviewsEnforcement, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection/required_pull_request_reviews", owner, repo, branch)
+	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", mediaTypeProtectedBranchesPreview)
+
+	r := new(PullRequestReviewsEnforcement)
+	resp, err := s.client.Do(ctx, req, r)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return r, resp, nil
+}
+
+// UpdatePullRequestReviewEnforcement patches pull request review enforcement of a protected branch.
+// It requires admin access and branch protection to be enabled.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#update-pull-request-review-enforcement-of-protected-branch
+func (s *RepositoriesService) UpdatePullRequestReviewEnforcement(ctx context.Context, owner, repo, branch string, patch *PullRequestReviewsEnforcementUpdate) (*PullRequestReviewsEnforcement, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection/required_pull_request_reviews", owner, repo, branch)
+	req, err := s.client.NewRequest("PATCH", u, patch)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches
+	req.Header.Set("Accept", mediaTypeProtectedBranchesPreview)
+
+	r := new(PullRequestReviewsEnforcement)
+	resp, err := s.client.Do(ctx, req, r)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return r, resp, err
+}
+
+// DisableDismissalRestrictions disables dismissal restrictions of a protected branch.
+// It requires admin access and branch protection to be enabled.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#update-pull-request-review-enforcement-of-protected-branch
+func (s *RepositoriesService) DisableDismissalRestrictions(ctx context.Context, owner, repo, branch string) (*PullRequestReviewsEnforcement, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection/required_pull_request_reviews", owner, repo, branch)
+
+	data := struct {
+		R []interface{} `json:"dismissal_restrictions"`
+	}{[]interface{}{}}
+
+	req, err := s.client.NewRequest("PATCH", u, data)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches
+	req.Header.Set("Accept", mediaTypeProtectedBranchesPreview)
+
+	r := new(PullRequestReviewsEnforcement)
+	resp, err := s.client.Do(ctx, req, r)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return r, resp, err
+}
+
+// RemovePullRequestReviewEnforcement removes pull request enforcement of a protected branch.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#remove-pull-request-review-enforcement-of-protected-branch
+func (s *RepositoriesService) RemovePullRequestReviewEnforcement(ctx context.Context, owner, repo, branch string) (*Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection/required_pull_request_reviews", owner, repo, branch)
+	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", mediaTypeProtectedBranchesPreview)
+
+	return s.client.Do(ctx, req, nil)
+}
+
+// GetAdminEnforcement gets admin enforcement information of a protected branch.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#get-admin-enforcement-of-protected-branch
+func (s *RepositoriesService) GetAdminEnforcement(ctx context.Context, owner, repo, branch string) (*AdminEnforcement, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection/enforce_admins", owner, repo, branch)
+	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", mediaTypeProtectedBranchesPreview)
+
+	r := new(AdminEnforcement)
+	resp, err := s.client.Do(ctx, req, r)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return r, resp, nil
+}
+
+// AddAdminEnforcement adds admin enforcement to a protected branch.
+// It requires admin access and branch protection to be enabled.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#add-admin-enforcement-of-protected-branch
+func (s *RepositoriesService) AddAdminEnforcement(ctx context.Context, owner, repo, branch string) (*AdminEnforcement, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection/enforce_admins", owner, repo, branch)
+	req, err := s.client.NewRequest("POST", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches
+	req.Header.Set("Accept", mediaTypeProtectedBranchesPreview)
+
+	r := new(AdminEnforcement)
+	resp, err := s.client.Do(ctx, req, r)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return r, resp, err
+}
+
+// RemoveAdminEnforcement removes admin enforcement from a protected branch.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/branches/#remove-admin-enforcement-of-protected-branch
+func (s *RepositoriesService) RemoveAdminEnforcement(ctx context.Context, owner, repo, branch string) (*Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/branches/%v/protection/enforce_admins", owner, repo, branch)
+	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", mediaTypeProtectedBranchesPreview)
+
+	return s.client.Do(ctx, req, nil)
+}
+
+// repositoryTopics represents a collection of repository topics.
+type repositoryTopics struct {
+	Names []string `json:"names"`
+}
+
+// ListAllTopics lists topics for a repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#list-all-topics-for-a-repository
+func (s *RepositoriesService) ListAllTopics(ctx context.Context, owner, repo string) ([]string, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/topics", owner, repo)
+	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", mediaTypeTopicsPreview)
+
+	topics := new(repositoryTopics)
+	resp, err := s.client.Do(ctx, req, topics)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return topics.Names, resp, nil
+}
+
+// ReplaceAllTopics replaces topics for a repository.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#replace-all-topics-for-a-repository
+func (s *RepositoriesService) ReplaceAllTopics(ctx context.Context, owner, repo string, topics []string) ([]string, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/topics", owner, repo)
+	t := &repositoryTopics{
+		Names: topics,
+	}
+	if t.Names == nil {
+		t.Names = []string{}
+	}
+	req, err := s.client.NewRequest("PUT", u, t)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches.
+	req.Header.Set("Accept", mediaTypeTopicsPreview)
+
+	t = new(repositoryTopics)
+	resp, err := s.client.Do(ctx, req, t)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return t.Names, resp, nil
+}
+
+// TransferRequest represents a request to transfer a repository.
+type TransferRequest struct {
+	NewOwner string  `json:"new_owner"`
+	TeamID   []int64 `json:"team_id,omitempty"`
+}
+
+// Transfer transfers a repository from one account or organization to another.
+//
+// This method might return an *AcceptedError and a status code of
+// 202. This is because this is the status that GitHub returns to signify that
+// it has now scheduled the transfer of the repository in a background task.
+// A follow up request, after a delay of a second or so, should result
+// in a successful request.
+//
+// GitHub API docs: https://developer.github.com/v3/repos/#transfer-a-repository
+func (s *RepositoriesService) Transfer(ctx context.Context, owner, repo string, transfer TransferRequest) (*Repository, *Response, error) {
+	u := fmt.Sprintf("repos/%v/%v/transfer", owner, repo)
+
+	req, err := s.client.NewRequest("POST", u, &transfer)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when this API fully launches.
+	req.Header.Set("Accept", mediaTypeRepositoryTransferPreview)
+
+	r := new(Repository)
+	resp, err := s.client.Do(ctx, req, r)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return r, resp, nil
+}