Add support for http_unix_socket (#30)

gh.go

@@ -15,6 +15,7 @@ import (
 
 	iapi "github.com/cli/go-gh/internal/api"
 	"github.com/cli/go-gh/internal/config"
+	iconfig "github.com/cli/go-gh/internal/config"
 	"github.com/cli/go-gh/internal/git"
 	irepo "github.com/cli/go-gh/internal/repository"
 	"github.com/cli/go-gh/pkg/api"
@@ -53,8 +54,9 @@ func run(path string, env []string, args ...string) (stdOut, stdErr bytes.Buffer
 }
 
 // RESTClient builds a client to send requests to GitHub REST API endpoints.
-// As part of the configuration a hostname, auth token, and default set of headers are resolved
-// from the gh environment configuration. These behaviors can be overridden using the opts argument.
+// As part of the configuration a hostname, auth token, default set of headers,
+// and unix domain socket are resolved from the gh environment configuration.
+// These behaviors can be overridden using the opts argument.
 func RESTClient(opts *api.ClientOptions) (api.RESTClient, error) {
 	if opts == nil {
 		opts = &api.ClientOptions{}
@@ -71,8 +73,9 @@ func RESTClient(opts *api.ClientOptions) (api.RESTClient, error) {
 }
 
 // GQLClient builds a client to send requests to GitHub GraphQL API endpoints.
-// As part of the configuration a hostname, auth token, and default set of headers are resolved
-// from the gh environment configuration. These behaviors can be overridden using the opts argument.
+// As part of the configuration a hostname, auth token, default set of headers,
+// and unix domain socket are resolved from the gh environment configuration.
+// These behaviors can be overridden using the opts argument.
 func GQLClient(opts *api.ClientOptions) (api.GQLClient, error) {
 	if opts == nil {
 		opts = &api.ClientOptions{}
@@ -89,12 +92,14 @@ func GQLClient(opts *api.ClientOptions) (api.GQLClient, error) {
 }
 
 // HTTPClient builds a client that can be passed to another library.
-// As part of the configuration a hostname, auth token, and default set of headers are resolved
-// from the gh environment configuration. These behaviors can be overridden using the opts argument.
-// In this instance providing opts.Host will not change the destination of your request as it is
-// the responsibility of the consumer to configure this. However, if opts.Host does not match the request
-// host, the auth token will not be added to the headers. This is to protect against the case where tokens
-// could be sent to an arbitrary host.
+// As part of the configuration a hostname, auth token, default set of headers,
+// and unix domain socket are resolved from the gh environment configuration.
+// These behaviors can be overridden using the opts argument. In this instance
+// providing opts.Host will not change the destination of your request as it is
+// the responsibility of the consumer to configure this. However, if opts.Host
+// does not match the request host, the auth token will not be added to the headers.
+// This is to protect against the case where tokens could be sent to an arbitrary
+// host.
 func HTTPClient(opts *api.ClientOptions) (*http.Client, error) {
 	if opts == nil {
 		opts = &api.ClientOptions{}
@@ -155,10 +160,19 @@ func resolveOptions(opts *api.ClientOptions, cfg config.Config) error {
 	if opts.AuthToken == "" {
 		token, err = cfg.AuthToken(opts.Host)
 		if err != nil {
-			return err
+			var notFoundError iconfig.NotFoundError
+			if errors.As(err, &notFoundError) {
+				return fmt.Errorf("authentication token not found for host %s", opts.Host)
+			} else {
+				return err
+			}
 		}
 		opts.AuthToken = token
 	}
+	if opts.UnixDomainSocket == "" {
+		unixSocket, _ := cfg.Get("http_unix_socket")
+		opts.UnixDomainSocket = unixSocket
+	}
 	return nil
 }
 

gh_test.go

@@ -168,21 +168,25 @@ func TestResolveOptions(t *testing.T) {
 		opts          *api.ClientOptions
 		wantAuthToken string
 		wantHost      string
+		wantSocket    string
 	}{
 		{
 			name: "honors consumer provided ClientOptions",
 			opts: &api.ClientOptions{
-				Host:      "test.com",
-				AuthToken: "token_from_opts",
+				Host:             "test.com",
+				AuthToken:        "token_from_opts",
+				UnixDomainSocket: "socket_from_opts",
 			},
 			wantAuthToken: "token_from_opts",
 			wantHost:      "test.com",
+			wantSocket:    "socket_from_opts",
 		},
 		{
 			name:          "uses config values if there are no consumer provided ClientOptions",
 			opts:          &api.ClientOptions{},
 			wantAuthToken: "token",
 			wantHost:      "github.com",
+			wantSocket:    "socket",
 		},
 	}
 
@@ -192,6 +196,7 @@ func TestResolveOptions(t *testing.T) {
 			assert.NoError(t, err)
 			assert.Equal(t, tt.wantHost, tt.opts.Host)
 			assert.Equal(t, tt.wantAuthToken, tt.opts.AuthToken)
+			assert.Equal(t, tt.wantSocket, tt.opts.UnixDomainSocket)
 		})
 	}
 }
@@ -203,6 +208,7 @@ hosts:
     user: user1
     oauth_token: token
     git_protocol: ssh
+http_unix_socket: socket
 `
 	cfg, _ := config.FromString(data)
 	return cfg

internal/api/http.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -74,11 +75,25 @@ func NewHTTPClient(opts *api.ClientOptions) http.Client {
 	}
 
 	transport := http.DefaultTransport
+
+	if opts.UnixDomainSocket != "" {
+		transport = newUnixDomainSocketRoundTripper(opts.UnixDomainSocket)
+	}
+
 	if opts.Transport != nil {
 		transport = opts.Transport
 	}
 
-	transport = newHeaderRoundTripper(opts.Host, opts.AuthToken, opts.Headers, transport)
+	if opts.EnableCache {
+		if opts.CacheDir == "" {
+			opts.CacheDir = filepath.Join(os.TempDir(), "gh-cli-cache")
+		}
+		if opts.CacheTTL == 0 {
+			opts.CacheTTL = time.Hour * 24
+		}
+		c := cache{dir: opts.CacheDir, ttl: opts.CacheTTL}
+		transport = c.RoundTripper(transport)
+	}
 
 	if opts.Log != nil {
 		logger := &httpretty.Logger{
@@ -99,25 +114,17 @@ func NewHTTPClient(opts *api.ClientOptions) http.Client {
 		transport = logger.RoundTripper(transport)
 	}
 
-	if opts.EnableCache {
-		if opts.CacheDir == "" {
-			opts.CacheDir = filepath.Join(os.TempDir(), "gh-cli-cache")
-		}
-		if opts.CacheTTL == 0 {
-			opts.CacheTTL = time.Hour * 24
-		}
-		c := cache{dir: opts.CacheDir, ttl: opts.CacheTTL}
-		transport = c.RoundTripper(transport)
-	}
+	transport = newHeaderRoundTripper(opts.Host, opts.AuthToken, opts.Headers, transport)
 
 	return http.Client{Transport: transport, Timeout: opts.Timeout}
 }
 
+// TODO: Export function in near future.
 func handleHTTPError(resp *http.Response) error {
 	httpError := api.HTTPError{
-		StatusCode:  resp.StatusCode,
-		RequestURL:  resp.Request.URL,
-		OAuthScopes: resp.Header.Get("X-Oauth-Scopes"),
+		StatusCode: resp.StatusCode,
+		RequestURL: resp.Request.URL,
+		Headers:    resp.Header,
 	}
 
 	if !jsonTypeRE.MatchString(resp.Header.Get(contentType)) {
@@ -198,19 +205,19 @@ func isEnterprise(host string) bool {
 }
 
 type headerRoundTripper struct {
-	host    string
 	headers map[string]string
+	host    string
 	rt      http.RoundTripper
 }
 
 func newHeaderRoundTripper(host string, authToken string, headers map[string]string, rt http.RoundTripper) http.RoundTripper {
 	if headers == nil {
 		headers = map[string]string{}
 	}
-	if headers[contentType] == "" {
+	if _, ok := headers[contentType]; !ok {
 		headers[contentType] = jsonContentType
 	}
-	if headers[userAgent] == "" {
+	if _, ok := headers[userAgent]; !ok {
 		headers[userAgent] = "go-gh"
 		info, ok := debug.ReadBuildInfo()
 		if ok {
@@ -222,13 +229,13 @@ func newHeaderRoundTripper(host string, authToken string, headers map[string]str
 			}
 		}
 	}
-	if headers[authorization] == "" && authToken != "" {
+	if _, ok := headers[authorization]; !ok && authToken != "" {
 		headers[authorization] = fmt.Sprintf("token %s", authToken)
 	}
-	if headers[timeZone] == "" {
+	if _, ok := headers[timeZone]; !ok {
 		headers[timeZone] = currentTimeZone()
 	}
-	if headers[accept] == "" {
+	if _, ok := headers[accept]; !ok {
 		// Preview for PullRequest.mergeStateStatus.
 		a := "application/vnd.github.merge-info-preview+json"
 		// Preview for visibility when RESTing repos into an org.
@@ -260,6 +267,18 @@ func (hrt headerRoundTripper) RoundTrip(req *http.Request) (*http.Response, erro
 	return hrt.rt.RoundTrip(req)
 }
 
+func newUnixDomainSocketRoundTripper(socketPath string) http.RoundTripper {
+	dial := func(network, addr string) (net.Conn, error) {
+		return net.Dial("unix", socketPath)
+	}
+
+	return &http.Transport{
+		Dial:              dial,
+		DialTLS:           dial,
+		DisableKeepAlives: true,
+	}
+}
+
 func currentTimeZone() string {
 	tz := time.Local.String()
 	if tz == "Local" {

internal/config/config.go

@@ -138,6 +138,7 @@ func defaultConfig() Config {
 	return config{global: configMap{Root: defaultGlobal().Content[0]}}
 }
 
+//TODO: Add caching so as not to load config multiple times.
 func Load() (Config, error) {
 	return load(configFile(), hostsConfigFile())
 }

pkg/api/client.go

@@ -32,7 +32,7 @@ type ClientOptions struct {
 	// Default headers will be overridden by keys specified in Headers.
 	Headers map[string]string
 
-	// Host is the host that every API request will be sent to.
+	// Host is the default host that API requests will be sent to.
 	Host string
 
 	// Log specifies a writer to write API request logs to.
@@ -44,8 +44,18 @@ type ClientOptions struct {
 	Timeout time.Duration
 
 	// Transport specifies the mechanism by which individual API requests are made.
+	// If both Transport and UnixDomainSocket are specified then Transport takes
+	// precedence. Due to this behavior any value set for Transport needs to manually
+	// handle routing to UnixDomainSocket if necessary. Generally, setting Transport
+	// should be reserved for testing purposes.
 	// Default is http.DefaultTransport.
 	Transport http.RoundTripper
+
+	// UnixDomainSocket specifies the Unix domain socket address by which individual
+	// API requests will be routed. If specifed, this will form the base of the API
+	// request transport chain.
+	// Default is no socket address.
+	UnixDomainSocket string
 }
 
 // RESTClient is the interface that wraps methods for the different types of

pkg/api/http.go

@@ -2,17 +2,18 @@ package api
 
 import (
 	"fmt"
+	"net/http"
 	"net/url"
 	"strings"
 )
 
 // HTTPError represents an error response from the GitHub API.
 type HTTPError struct {
-	StatusCode  int
-	RequestURL  *url.URL
-	Message     string
-	OAuthScopes string
-	Errors      []HTTPErrorItem
+	Errors     []HTTPErrorItem
+	Headers    http.Header
+	Message    string
+	RequestURL *url.URL
+	StatusCode int
 }
 
 // HTTPErrorItem stores additional information about an error response