Merge branch 'main' into noretry-header-cert

.github/workflows/actionlint.yml

@@ -12,7 +12,7 @@ jobs:
   actionlint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@8f4b7f84864484a7bf31766abe9204da3cbe65b3 # v3.5.0
+      - uses: actions/checkout@44c2b7a8a4ea60a981eaca3cf939b5f4305c123b # v4.1.5
       - name: "Check GitHub workflow files"
         uses: docker://docker.mirror.hashicorp.services/rhysd/actionlint:latest
         with:

.github/workflows/pr-gofmt.yaml

@@ -0,0 +1,23 @@
+name: Go format check
+on:
+  pull_request:
+    types: ['opened', 'synchronize']
+
+jobs:
+  run-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@44c2b7a8a4ea60a981eaca3cf939b5f4305c123b # v4.1.5
+
+      - uses: actions/setup-go@cdcb36043654635271a94b9a6d1392de5bb323a7 # v5.0.1
+        with:
+          go-version-file: ./.go-version
+
+      - name: Run go format
+        run: |-
+          files=$(gofmt -s -l .)
+          if [ -n "$files" ]; then
+            echo >&2 "The following file(s) are not gofmt compliant:"
+            echo >&2 "$files"
+            exit 1
+          fi

.github/workflows/pr-unit-tests-1.19.yaml

@@ -0,0 +1,17 @@
+name: Unit tests (Go 1.19)
+on:
+  pull_request:
+    types: ['opened', 'synchronize']
+
+jobs:
+  run-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@44c2b7a8a4ea60a981eaca3cf939b5f4305c123b # v4.1.5
+
+      - uses: actions/setup-go@cdcb36043654635271a94b9a6d1392de5bb323a7 # v5.0.1
+        with:
+          go-version: 1.19
+
+      - name: Run unit tests
+        run: make test

.github/workflows/pr-unit-tests-1.20.yaml

@@ -0,0 +1,17 @@
+name: Unit tests (Go 1.20+)
+on:
+  pull_request:
+    types: ['opened', 'synchronize']
+
+jobs:
+  run-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@44c2b7a8a4ea60a981eaca3cf939b5f4305c123b # v4.1.5
+
+      - uses: actions/setup-go@cdcb36043654635271a94b9a6d1392de5bb323a7 # v5.0.1
+        with:
+          go-version: 1.22
+
+      - name: Run unit tests
+        run: make test

.go-version

@@ -0,0 +1 @@
+1.22.2

CHANGELOG.md

@@ -1,14 +1,22 @@
+## 0.7.6 (Unreleased)
+
+ENHANCEMENTS:
+
+- client: support a `RetryPrepare` function for modifying the request before retrying (#216)
+- client: support HTTP-date values for `Retry-After` header value (#138)
+- client: avoid reading entire body when the body is a `*bytes.Reader` (#197)
+
 ## 0.7.5 (Nov 8, 2023)
 
-BUG FIXES
+BUG FIXES:
 
-- client: fixes an issue where the request body is not preserved on temporary redirects or re-established HTTP/2 connections [GH-207]
+- client: fixes an issue where the request body is not preserved on temporary redirects or re-established HTTP/2 connections (#207)
 
 ## 0.7.4 (Jun 6, 2023)
 
-BUG FIXES
+BUG FIXES:
 
-- client: fixing an issue where the Content-Type header wouldn't be sent with an empty payload when using HTTP/2 [GH-194]
+- client: fixing an issue where the Content-Type header wouldn't be sent with an empty payload when using HTTP/2 (#194)
 
 ## 0.7.3 (May 15, 2023)
 

CODEOWNERS

@@ -1 +1 @@
-* @hashicorp/release-engineering
+* @hashicorp/go-retryablehttp-maintainers

Makefile

@@ -2,7 +2,7 @@ default: test
 
 test:
 	go vet ./...
-	go test -race ./...
+	go test -v -race ./...
 
 updatedeps:
 	go get -f -t -u ./...

README.md

@@ -59,4 +59,4 @@ standardClient := retryClient.StandardClient() // *http.Client
 ```
 
 For more usage and examples see the
-[godoc](http://godoc.org/github.com/hashicorp/go-retryablehttp).
+[pkg.go.dev](https://pkg.go.dev/github.com/hashicorp/go-retryablehttp).

client.go

@@ -29,7 +29,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"math"
 	"math/rand"
@@ -62,6 +61,10 @@ var (
 	// limit the size we consume to respReadLimit.
 	respReadLimit = int64(4096)
 
+	// timeNow sets the function that returns the current time.
+	// This defaults to time.Now. Changes to this should only be done in tests.
+	timeNow = time.Now
+
 	// A regular expression to match the error returned by net/http when the
 	// configured number of redirects is exhausted. This error isn't typed
 	// specifically so we resort to matching on the error string.
@@ -252,29 +255,27 @@ func getBodyReaderAndContentLength(rawBody interface{}) (ReaderFunc, int64, erro
 	// deal with it seeking so want it to match here instead of the
 	// io.ReadSeeker case.
 	case *bytes.Reader:
-		buf, err := ioutil.ReadAll(body)
-		if err != nil {
-			return nil, 0, err
-		}
+		snapshot := *body
 		bodyReader = func() (io.Reader, error) {
-			return bytes.NewReader(buf), nil
+			r := snapshot
+			return &r, nil
 		}
-		contentLength = int64(len(buf))
+		contentLength = int64(body.Len())
 
 	// Compat case
 	case io.ReadSeeker:
 		raw := body
 		bodyReader = func() (io.Reader, error) {
 			_, err := raw.Seek(0, 0)
-			return ioutil.NopCloser(raw), err
+			return io.NopCloser(raw), err
 		}
 		if lr, ok := raw.(LenReader); ok {
 			contentLength = int64(lr.Len())
 		}
 
 	// Read all in so we can reset
 	case io.Reader:
-		buf, err := ioutil.ReadAll(body)
+		buf, err := io.ReadAll(body)
 		if err != nil {
 			return nil, 0, err
 		}
@@ -397,6 +398,9 @@ type Backoff func(min, max time.Duration, attemptNum int, resp *http.Response) t
 // attempted. If overriding this, be sure to close the body if needed.
 type ErrorHandler func(resp *http.Response, err error, numTries int) (*http.Response, error)
 
+// PrepareRetry is called before retry operation. It can be used for example to re-sign the request
+type PrepareRetry func(req *http.Request) error
+
 // Client is used to make HTTP requests. It adds additional functionality
 // like automatic retries to tolerate minor outages.
 type Client struct {
@@ -425,6 +429,9 @@ type Client struct {
 	// ErrorHandler specifies the custom error handler to use, if any
 	ErrorHandler ErrorHandler
 
+	// PrepareRetry can prepare the request for retry operation, for example re-sign it
+	PrepareRetry PrepareRetry
+
 	loggerInit sync.Once
 	clientInit sync.Once
 }
@@ -544,10 +551,8 @@ func baseRetryPolicy(resp *http.Response, err error) (bool, error) {
 func DefaultBackoff(min, max time.Duration, attemptNum int, resp *http.Response) time.Duration {
 	if resp != nil {
 		if resp.StatusCode == http.StatusTooManyRequests || resp.StatusCode == http.StatusServiceUnavailable {
-			if s, ok := resp.Header["Retry-After"]; ok {
-				if sleep, err := strconv.ParseInt(s[0], 10, 64); err == nil {
-					return time.Second * time.Duration(sleep)
-				}
+			if sleep, ok := parseRetryAfterHeader(resp.Header["Retry-After"]); ok {
+				return sleep
 			}
 		}
 	}
@@ -560,6 +565,41 @@ func DefaultBackoff(min, max time.Duration, attemptNum int, resp *http.Response)
 	return sleep
 }
 
+// parseRetryAfterHeader parses the Retry-After header and returns the
+// delay duration according to the spec: https://httpwg.org/specs/rfc7231.html#header.retry-after
+// The bool returned will be true if the header was successfully parsed.
+// Otherwise, the header was either not present, or was not parseable according to the spec.
+//
+// Retry-After headers come in two flavors: Seconds or HTTP-Date
+//
+// Examples:
+// * Retry-After: Fri, 31 Dec 1999 23:59:59 GMT
+// * Retry-After: 120
+func parseRetryAfterHeader(headers []string) (time.Duration, bool) {
+	if len(headers) == 0 || headers[0] == "" {
+		return 0, false
+	}
+	header := headers[0]
+	// Retry-After: 120
+	if sleep, err := strconv.ParseInt(header, 10, 64); err == nil {
+		if sleep < 0 { // a negative sleep doesn't make sense
+			return 0, false
+		}
+		return time.Second * time.Duration(sleep), true
+	}
+
+	// Retry-After: Fri, 31 Dec 1999 23:59:59 GMT
+	retryTime, err := time.Parse(time.RFC1123, header)
+	if err != nil {
+		return 0, false
+	}
+	if until := retryTime.Sub(timeNow()); until > 0 {
+		return until, true
+	}
+	// date is in the past
+	return 0, true
+}
+
 // LinearJitterBackoff provides a callback for Client.Backoff which will
 // perform linear backoff based on the attempt number and with jitter to
 // prevent a thundering herd.
@@ -587,13 +627,13 @@ func LinearJitterBackoff(min, max time.Duration, attemptNum int, resp *http.Resp
 	}
 
 	// Seed rand; doing this every time is fine
-	rand := rand.New(rand.NewSource(int64(time.Now().Nanosecond())))
+	source := rand.New(rand.NewSource(int64(time.Now().Nanosecond())))
 
 	// Pick a random number that lies somewhere between the min and max and
 	// multiply by the attemptNum. attemptNum starts at zero so we always
 	// increment here. We first get a random percentage, then apply that to the
 	// difference between min and max, and add to min.
-	jitter := rand.Float64() * float64(max-min)
+	jitter := source.Float64() * float64(max-min)
 	jitterMin := int64(jitter) + int64(min)
 	return time.Duration(jitterMin * int64(attemptNum))
 }
@@ -627,10 +667,10 @@ func (c *Client) Do(req *Request) (*http.Response, error) {
 	var resp *http.Response
 	var attempt int
 	var shouldRetry bool
-	var doErr, respErr, checkErr error
+	var doErr, respErr, checkErr, prepareErr error
 
 	for i := 0; ; i++ {
-		doErr, respErr = nil, nil
+		doErr, respErr, prepareErr = nil, nil, nil
 		attempt++
 
 		// Always rewind the request body when non-nil.
@@ -643,7 +683,7 @@ func (c *Client) Do(req *Request) (*http.Response, error) {
 			if c, ok := body.(io.ReadCloser); ok {
 				req.Body = c
 			} else {
-				req.Body = ioutil.NopCloser(body)
+				req.Body = io.NopCloser(body)
 			}
 		}
 
@@ -737,17 +777,26 @@ func (c *Client) Do(req *Request) (*http.Response, error) {
 		// without racing against the closeBody call in persistConn.writeLoop.
 		httpreq := *req.Request
 		req.Request = &httpreq
+
+		if c.PrepareRetry != nil {
+			if err := c.PrepareRetry(req.Request); err != nil {
+				prepareErr = err
+				break
+			}
+		}
 	}
 
 	// this is the closest we have to success criteria
-	if doErr == nil && respErr == nil && checkErr == nil && !shouldRetry {
+	if doErr == nil && respErr == nil && checkErr == nil && prepareErr == nil && !shouldRetry {
 		return resp, nil
 	}
 
 	defer c.HTTPClient.CloseIdleConnections()
 
 	var err error
-	if checkErr != nil {
+	if prepareErr != nil {
+		err = prepareErr
+	} else if checkErr != nil {
 		err = checkErr
 	} else if respErr != nil {
 		err = respErr
@@ -779,7 +828,7 @@ func (c *Client) Do(req *Request) (*http.Response, error) {
 // Try to read the response body so we can reuse this connection.
 func (c *Client) drainBody(body io.ReadCloser) {
 	defer body.Close()
-	_, err := io.Copy(ioutil.Discard, io.LimitReader(body, respReadLimit))
+	_, err := io.Copy(io.Discard, io.LimitReader(body, respReadLimit))
 	if err != nil {
 		if c.logger() != nil {
 			switch v := c.logger().(type) {