Add ability to trace CloudAPI HTTP requests (#180)

CHANGELOG.md

@@ -1,5 +1,11 @@
 ## Unreleased
 
+## 1.8.1 (May 4 2020)
+
+- Add ability to trace CloudAPI HTTP requests [#180]. You can set the
+  TRITON_TRACE_HTTP environment variable to have the CloudAPI HTTP requests and
+  responses be printed to stderr.
+
 ## 1.8.0 (April 27 2020)
 
 - Update Triton acceptance tests to work with any Triton [#178]

README.md

@@ -120,6 +120,8 @@ Additionally, you may set these optional environment variables:
     is set, the PrivateKeySigner (see above) will be used - if not the
     SSHAgentSigner will be used. You can also set `TRITON_USER` to run the tests
     against an account other than the main Triton account.
+- `TRITON_TRACE_HTTP` - when set this will print the HTTP requests and responses
+  to stderr.
 - `TRITON_VERBOSE_TESTS` - turns on extra logging for test runs
 
 ### Example Run

client/client.go

@@ -18,13 +18,15 @@ import (
 	"net"
 	"net/http"
 	"net/url"
+	"os"
 	"regexp"
 	"strings"
 	"time"
 
 	triton "github.com/joyent/triton-go"
 	"github.com/joyent/triton-go/authentication"
 	"github.com/joyent/triton-go/errors"
+	tritonutils "github.com/joyent/triton-go/utils"
 	pkgerrors "github.com/pkg/errors"
 )
 
@@ -46,6 +48,9 @@ var (
 
 	jpcFormatURL = "https://tsg.%s.svc.joyent.zone"
 	spcFormatURL = "https://tsg.%s.svc.samsungcloud.zone"
+
+	tritonTransportHttpTraceChecked = false
+	tritonTransportHttpTraceEnabled = false
 )
 
 // Client represents a connection to the Triton Compute or Object Storage APIs.
@@ -72,6 +77,21 @@ func isPrivateInstall(url string) bool {
 	return true
 }
 
+func wrapTritonTransport(in http.RoundTripper) http.RoundTripper {
+	if tritonTransportHttpTraceChecked == false {
+		tritonTransportHttpTraceChecked = true
+		if os.Getenv("TRITON_TRACE_HTTP") != "" {
+			tritonTransportHttpTraceEnabled = true
+		}
+	}
+
+	if tritonTransportHttpTraceEnabled {
+		return tritonutils.TraceRoundTripper(in)
+	}
+
+	return in
+}
+
 // parseDC parses out the data center commonly found in Triton URLs. Returns an
 // error if the Triton URL does not include a known data center name, in which
 // case a URL override (TRITON_TSG_URL) must be provided.
@@ -158,6 +178,9 @@ func New(tritonURL string, mantaURL string, accountName string, signers ...authe
 		AccountName: accountName,
 	}
 
+	// Allow wrapping of the HTTP Transport.
+	newClient.HTTPClient.Transport = wrapTritonTransport(newClient.HTTPClient.Transport)
+
 	// Default to constructing an SSHAgentSigner if there are no other signers
 	// passed into NewClient and there's an TRITON_KEY_ID and SSH_AUTH_SOCK
 	// available in the user's environ(7).
@@ -202,6 +225,8 @@ func (c *Client) InsecureSkipTLSVerify() {
 	}
 
 	c.HTTPClient.Transport = httpTransport(true)
+	// Allow wrapping of the HTTP Transport.
+	c.HTTPClient.Transport = wrapTritonTransport(c.HTTPClient.Transport)
 }
 
 // httpTransport is responsible for setting up our HTTP client's transport

utils/http_debugging.go

@@ -0,0 +1,64 @@
+//
+// Copyright 2020 Joyent, Inc.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+//
+
+package utils
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httputil"
+	"os"
+)
+
+// This file is used for tracing HTTP requests (trace).
+//
+// All HTTP requests and responses through this transport will be printed to
+// stderr.
+
+// TraceRoundTripper to wrap a HTTP Transport.
+func TraceRoundTripper(in http.RoundTripper) http.RoundTripper {
+	return &traceRoundTripper{inner: in, logger: os.Stderr}
+}
+
+type traceRoundTripper struct {
+	inner  http.RoundTripper
+	logger io.Writer
+}
+
+func (d *traceRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	d.dumpRequest(req)
+	res, err := d.inner.RoundTrip(req)
+	d.dumpResponse(res)
+	return res, err
+}
+
+func (d *traceRoundTripper) dumpRequest(r *http.Request) {
+	dump, err := httputil.DumpRequestOut(r, true)
+	if err != nil {
+		fmt.Fprintf(d.logger, "\n\tERROR dumping: %v\n", err)
+		return
+	}
+	d.dump("REQUEST", dump)
+}
+
+func (d *traceRoundTripper) dumpResponse(r *http.Response) {
+	dump, err := httputil.DumpResponse(r, true)
+	if err != nil {
+		fmt.Fprintf(d.logger, "\n\tERROR dumping: %v\n", err)
+		return
+	}
+	d.dump("RESPONSE", dump)
+}
+
+func (d *traceRoundTripper) dump(label string, dump []byte) {
+	fmt.Fprintf(d.logger, "\n%s:\n--\n%s\n", label, string(dump))
+	if label == "RESPONSE" {
+		fmt.Fprintf(d.logger, "\n")
+	}
+}

version.go

@@ -15,7 +15,7 @@ import (
 
 // Version represents main version number of the current release
 // of the Triton-go SDK.
-const Version = "1.8.0"
+const Version = "1.8.1"
 
 // Prerelease adds a pre-release marker to the version.
 //