From 8c12c6939aab9106db14ec2d11d983bc5b29fb2c Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Sun, 7 Jul 2019 21:33:44 +0100 Subject: Switch to modules --- .../github.com/hashicorp/go-retryablehttp/LICENSE | 363 --------------- .../github.com/hashicorp/go-retryablehttp/Makefile | 11 - .../hashicorp/go-retryablehttp/README.md | 46 -- .../hashicorp/go-retryablehttp/client.go | 500 --------------------- 4 files changed, 920 deletions(-) delete mode 100644 vendor/github.com/hashicorp/go-retryablehttp/LICENSE delete mode 100644 vendor/github.com/hashicorp/go-retryablehttp/Makefile delete mode 100644 vendor/github.com/hashicorp/go-retryablehttp/README.md delete mode 100644 vendor/github.com/hashicorp/go-retryablehttp/client.go (limited to 'vendor/github.com/hashicorp/go-retryablehttp') diff --git a/vendor/github.com/hashicorp/go-retryablehttp/LICENSE b/vendor/github.com/hashicorp/go-retryablehttp/LICENSE deleted file mode 100644 index e87a115..0000000 --- a/vendor/github.com/hashicorp/go-retryablehttp/LICENSE +++ /dev/null @@ -1,363 +0,0 @@ -Mozilla Public License, version 2.0 - -1. Definitions - -1.1. "Contributor" - - means each individual or legal entity that creates, contributes to the - creation of, or owns Covered Software. - -1.2. "Contributor Version" - - means the combination of the Contributions of others (if any) used by a - Contributor and that particular Contributor's Contribution. - -1.3. "Contribution" - - means Covered Software of a particular Contributor. - -1.4. "Covered Software" - - means Source Code Form to which the initial Contributor has attached the - notice in Exhibit A, the Executable Form of such Source Code Form, and - Modifications of such Source Code Form, in each case including portions - thereof. - -1.5. "Incompatible With Secondary Licenses" - means - - a. that the initial Contributor has attached the notice described in - Exhibit B to the Covered Software; or - - b. that the Covered Software was made available under the terms of - version 1.1 or earlier of the License, but not also under the terms of - a Secondary License. - -1.6. "Executable Form" - - means any form of the work other than Source Code Form. - -1.7. "Larger Work" - - means a work that combines Covered Software with other material, in a - separate file or files, that is not Covered Software. - -1.8. "License" - - means this document. - -1.9. "Licensable" - - means having the right to grant, to the maximum extent possible, whether - at the time of the initial grant or subsequently, any and all of the - rights conveyed by this License. - -1.10. "Modifications" - - means any of the following: - - a. any file in Source Code Form that results from an addition to, - deletion from, or modification of the contents of Covered Software; or - - b. any new file in Source Code Form that contains any Covered Software. - -1.11. "Patent Claims" of a Contributor - - means any patent claim(s), including without limitation, method, - process, and apparatus claims, in any patent Licensable by such - Contributor that would be infringed, but for the grant of the License, - by the making, using, selling, offering for sale, having made, import, - or transfer of either its Contributions or its Contributor Version. - -1.12. "Secondary License" - - means either the GNU General Public License, Version 2.0, the GNU Lesser - General Public License, Version 2.1, the GNU Affero General Public - License, Version 3.0, or any later versions of those licenses. - -1.13. "Source Code Form" - - means the form of the work preferred for making modifications. - -1.14. "You" (or "Your") - - means an individual or a legal entity exercising rights under this - License. For legal entities, "You" includes any entity that controls, is - controlled by, or is under common control with You. For purposes of this - definition, "control" means (a) the power, direct or indirect, to cause - the direction or management of such entity, whether by contract or - otherwise, or (b) ownership of more than fifty percent (50%) of the - outstanding shares or beneficial ownership of such entity. - - -2. License Grants and Conditions - -2.1. Grants - - Each Contributor hereby grants You a world-wide, royalty-free, - non-exclusive license: - - a. under intellectual property rights (other than patent or trademark) - Licensable by such Contributor to use, reproduce, make available, - modify, display, perform, distribute, and otherwise exploit its - Contributions, either on an unmodified basis, with Modifications, or - as part of a Larger Work; and - - b. under Patent Claims of such Contributor to make, use, sell, offer for - sale, have made, import, and otherwise transfer either its - Contributions or its Contributor Version. - -2.2. Effective Date - - The licenses granted in Section 2.1 with respect to any Contribution - become effective for each Contribution on the date the Contributor first - distributes such Contribution. - -2.3. Limitations on Grant Scope - - The licenses granted in this Section 2 are the only rights granted under - this License. No additional rights or licenses will be implied from the - distribution or licensing of Covered Software under this License. - Notwithstanding Section 2.1(b) above, no patent license is granted by a - Contributor: - - a. for any code that a Contributor has removed from Covered Software; or - - b. for infringements caused by: (i) Your and any other third party's - modifications of Covered Software, or (ii) the combination of its - Contributions with other software (except as part of its Contributor - Version); or - - c. under Patent Claims infringed by Covered Software in the absence of - its Contributions. - - This License does not grant any rights in the trademarks, service marks, - or logos of any Contributor (except as may be necessary to comply with - the notice requirements in Section 3.4). - -2.4. Subsequent Licenses - - No Contributor makes additional grants as a result of Your choice to - distribute the Covered Software under a subsequent version of this - License (see Section 10.2) or under the terms of a Secondary License (if - permitted under the terms of Section 3.3). - -2.5. Representation - - Each Contributor represents that the Contributor believes its - Contributions are its original creation(s) or it has sufficient rights to - grant the rights to its Contributions conveyed by this License. - -2.6. Fair Use - - This License is not intended to limit any rights You have under - applicable copyright doctrines of fair use, fair dealing, or other - equivalents. - -2.7. Conditions - - Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted in - Section 2.1. - - -3. Responsibilities - -3.1. Distribution of Source Form - - All distribution of Covered Software in Source Code Form, including any - Modifications that You create or to which You contribute, must be under - the terms of this License. You must inform recipients that the Source - Code Form of the Covered Software is governed by the terms of this - License, and how they can obtain a copy of this License. You may not - attempt to alter or restrict the recipients' rights in the Source Code - Form. - -3.2. Distribution of Executable Form - - If You distribute Covered Software in Executable Form then: - - a. such Covered Software must also be made available in Source Code Form, - as described in Section 3.1, and You must inform recipients of the - Executable Form how they can obtain a copy of such Source Code Form by - reasonable means in a timely manner, at a charge no more than the cost - of distribution to the recipient; and - - b. You may distribute such Executable Form under the terms of this - License, or sublicense it under different terms, provided that the - license for the Executable Form does not attempt to limit or alter the - recipients' rights in the Source Code Form under this License. - -3.3. Distribution of a Larger Work - - You may create and distribute a Larger Work under terms of Your choice, - provided that You also comply with the requirements of this License for - the Covered Software. If the Larger Work is a combination of Covered - Software with a work governed by one or more Secondary Licenses, and the - Covered Software is not Incompatible With Secondary Licenses, this - License permits You to additionally distribute such Covered Software - under the terms of such Secondary License(s), so that the recipient of - the Larger Work may, at their option, further distribute the Covered - Software under the terms of either this License or such Secondary - License(s). - -3.4. Notices - - You may not remove or alter the substance of any license notices - (including copyright notices, patent notices, disclaimers of warranty, or - limitations of liability) contained within the Source Code Form of the - Covered Software, except that You may alter any license notices to the - extent required to remedy known factual inaccuracies. - -3.5. Application of Additional Terms - - You may choose to offer, and to charge a fee for, warranty, support, - indemnity or liability obligations to one or more recipients of Covered - Software. However, You may do so only on Your own behalf, and not on - behalf of any Contributor. You must make it absolutely clear that any - such warranty, support, indemnity, or liability obligation is offered by - You alone, and You hereby agree to indemnify every Contributor for any - liability incurred by such Contributor as a result of warranty, support, - indemnity or liability terms You offer. You may include additional - disclaimers of warranty and limitations of liability specific to any - jurisdiction. - -4. Inability to Comply Due to Statute or Regulation - - If it is impossible for You to comply with any of the terms of this License - with respect to some or all of the Covered Software due to statute, - judicial order, or regulation then You must: (a) comply with the terms of - this License to the maximum extent possible; and (b) describe the - limitations and the code they affect. Such description must be placed in a - text file included with all distributions of the Covered Software under - this License. Except to the extent prohibited by statute or regulation, - such description must be sufficiently detailed for a recipient of ordinary - skill to be able to understand it. - -5. Termination - -5.1. The rights granted under this License will terminate automatically if You - fail to comply with any of its terms. However, if You become compliant, - then the rights granted under this License from a particular Contributor - are reinstated (a) provisionally, unless and until such Contributor - explicitly and finally terminates Your grants, and (b) on an ongoing - basis, if such Contributor fails to notify You of the non-compliance by - some reasonable means prior to 60 days after You have come back into - compliance. Moreover, Your grants from a particular Contributor are - reinstated on an ongoing basis if such Contributor notifies You of the - non-compliance by some reasonable means, this is the first time You have - received notice of non-compliance with this License from such - Contributor, and You become compliant prior to 30 days after Your receipt - of the notice. - -5.2. If You initiate litigation against any entity by asserting a patent - infringement claim (excluding declaratory judgment actions, - counter-claims, and cross-claims) alleging that a Contributor Version - directly or indirectly infringes any patent, then the rights granted to - You by any and all Contributors for the Covered Software under Section - 2.1 of this License shall terminate. - -5.3. In the event of termination under Sections 5.1 or 5.2 above, all end user - license agreements (excluding distributors and resellers) which have been - validly granted by You or Your distributors under this License prior to - termination shall survive termination. - -6. Disclaimer of Warranty - - Covered Software is provided under this License on an "as is" basis, - without warranty of any kind, either expressed, implied, or statutory, - including, without limitation, warranties that the Covered Software is free - of defects, merchantable, fit for a particular purpose or non-infringing. - The entire risk as to the quality and performance of the Covered Software - is with You. Should any Covered Software prove defective in any respect, - You (not any Contributor) assume the cost of any necessary servicing, - repair, or correction. This disclaimer of warranty constitutes an essential - part of this License. No use of any Covered Software is authorized under - this License except under this disclaimer. - -7. Limitation of Liability - - Under no circumstances and under no legal theory, whether tort (including - negligence), contract, or otherwise, shall any Contributor, or anyone who - distributes Covered Software as permitted above, be liable to You for any - direct, indirect, special, incidental, or consequential damages of any - character including, without limitation, damages for lost profits, loss of - goodwill, work stoppage, computer failure or malfunction, or any and all - other commercial damages or losses, even if such party shall have been - informed of the possibility of such damages. This limitation of liability - shall not apply to liability for death or personal injury resulting from - such party's negligence to the extent applicable law prohibits such - limitation. Some jurisdictions do not allow the exclusion or limitation of - incidental or consequential damages, so this exclusion and limitation may - not apply to You. - -8. Litigation - - Any litigation relating to this License may be brought only in the courts - of a jurisdiction where the defendant maintains its principal place of - business and such litigation shall be governed by laws of that - jurisdiction, without reference to its conflict-of-law provisions. Nothing - in this Section shall prevent a party's ability to bring cross-claims or - counter-claims. - -9. Miscellaneous - - This License represents the complete agreement concerning the subject - matter hereof. If any provision of this License is held to be - unenforceable, such provision shall be reformed only to the extent - necessary to make it enforceable. Any law or regulation which provides that - the language of a contract shall be construed against the drafter shall not - be used to construe this License against a Contributor. - - -10. Versions of the License - -10.1. New Versions - - Mozilla Foundation is the license steward. Except as provided in Section - 10.3, no one other than the license steward has the right to modify or - publish new versions of this License. Each version will be given a - distinguishing version number. - -10.2. Effect of New Versions - - You may distribute the Covered Software under the terms of the version - of the License under which You originally received the Covered Software, - or under the terms of any subsequent version published by the license - steward. - -10.3. Modified Versions - - If you create software not governed by this License, and you want to - create a new license for such software, you may create and use a - modified version of this License if you rename the license and remove - any references to the name of the license steward (except to note that - such modified license differs from this License). - -10.4. Distributing Source Code Form that is Incompatible With Secondary - Licenses If You choose to distribute Source Code Form that is - Incompatible With Secondary Licenses under the terms of this version of - the License, the notice described in Exhibit B of this License must be - attached. - -Exhibit A - Source Code Form License Notice - - 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/. - -If it is not possible or desirable to put the notice in a particular file, -then You may include the notice in a location (such as a LICENSE file in a -relevant directory) where a recipient would be likely to look for such a -notice. - -You may add additional accurate notices of copyright ownership. - -Exhibit B - "Incompatible With Secondary Licenses" Notice - - This Source Code Form is "Incompatible - With Secondary Licenses", as defined by - the Mozilla Public License, v. 2.0. - diff --git a/vendor/github.com/hashicorp/go-retryablehttp/Makefile b/vendor/github.com/hashicorp/go-retryablehttp/Makefile deleted file mode 100644 index da17640..0000000 --- a/vendor/github.com/hashicorp/go-retryablehttp/Makefile +++ /dev/null @@ -1,11 +0,0 @@ -default: test - -test: - go vet ./... - go test -race ./... - -updatedeps: - go get -f -t -u ./... - go get -f -u ./... - -.PHONY: default test updatedeps diff --git a/vendor/github.com/hashicorp/go-retryablehttp/README.md b/vendor/github.com/hashicorp/go-retryablehttp/README.md deleted file mode 100644 index ccdc7e8..0000000 --- a/vendor/github.com/hashicorp/go-retryablehttp/README.md +++ /dev/null @@ -1,46 +0,0 @@ -go-retryablehttp -================ - -[![Build Status](http://img.shields.io/travis/hashicorp/go-retryablehttp.svg?style=flat-square)][travis] -[![Go Documentation](http://img.shields.io/badge/go-documentation-blue.svg?style=flat-square)][godocs] - -[travis]: http://travis-ci.org/hashicorp/go-retryablehttp -[godocs]: http://godoc.org/github.com/hashicorp/go-retryablehttp - -The `retryablehttp` package provides a familiar HTTP client interface with -automatic retries and exponential backoff. It is a thin wrapper over the -standard `net/http` client library and exposes nearly the same public API. This -makes `retryablehttp` very easy to drop into existing programs. - -`retryablehttp` performs automatic retries under certain conditions. Mainly, if -an error is returned by the client (connection errors, etc.), or if a 500-range -response code is received (except 501), then a retry is invoked after a wait -period. Otherwise, the response is returned and left to the caller to -interpret. - -The main difference from `net/http` is that requests which take a request body -(POST/PUT et. al) can have the body provided in a number of ways (some more or -less efficient) that allow "rewinding" the request body if the initial request -fails so that the full request can be attempted again. See the -[godoc](http://godoc.org/github.com/hashicorp/go-retryablehttp) for more -details. - -Example Use -=========== - -Using this library should look almost identical to what you would do with -`net/http`. The most simple example of a GET request is shown below: - -```go -resp, err := retryablehttp.Get("/foo") -if err != nil { - panic(err) -} -``` - -The returned response object is an `*http.Response`, the same thing you would -usually get from `net/http`. Had the request failed one or more times, the above -call would block and retry with exponential backoff. - -For more usage and examples see the -[godoc](http://godoc.org/github.com/hashicorp/go-retryablehttp). diff --git a/vendor/github.com/hashicorp/go-retryablehttp/client.go b/vendor/github.com/hashicorp/go-retryablehttp/client.go deleted file mode 100644 index 21f45e5..0000000 --- a/vendor/github.com/hashicorp/go-retryablehttp/client.go +++ /dev/null @@ -1,500 +0,0 @@ -// The retryablehttp package provides a familiar HTTP client interface with -// automatic retries and exponential backoff. It is a thin wrapper over the -// standard net/http client library and exposes nearly the same public API. -// This makes retryablehttp very easy to drop into existing programs. -// -// retryablehttp performs automatic retries under certain conditions. Mainly, if -// an error is returned by the client (connection errors etc), or if a 500-range -// response is received, then a retry is invoked. Otherwise, the response is -// returned and left to the caller to interpret. -// -// Requests which take a request body should provide a non-nil function -// parameter. The best choice is to provide either a function satisfying -// ReaderFunc which provides multiple io.Readers in an efficient manner, a -// *bytes.Buffer (the underlying raw byte slice will be used) or a raw byte -// slice. As it is a reference type, and we will wrap it as needed by readers, -// we can efficiently re-use the request body without needing to copy it. If an -// io.Reader (such as a *bytes.Reader) is provided, the full body will be read -// prior to the first request, and will be efficiently re-used for any retries. -// ReadSeeker can be used, but some users have observed occasional data races -// between the net/http library and the Seek functionality of some -// implementations of ReadSeeker, so should be avoided if possible. -package retryablehttp - -import ( - "bytes" - "context" - "fmt" - "io" - "io/ioutil" - "log" - "math" - "math/rand" - "net/http" - "net/url" - "os" - "strings" - "time" - - "github.com/hashicorp/go-cleanhttp" -) - -var ( - // Default retry configuration - defaultRetryWaitMin = 1 * time.Second - defaultRetryWaitMax = 30 * time.Second - defaultRetryMax = 4 - - // defaultClient is used for performing requests without explicitly making - // a new client. It is purposely private to avoid modifications. - defaultClient = NewClient() - - // We need to consume response bodies to maintain http connections, but - // limit the size we consume to respReadLimit. - respReadLimit = int64(4096) -) - -// ReaderFunc is the type of function that can be given natively to NewRequest -type ReaderFunc func() (io.Reader, error) - -// LenReader is an interface implemented by many in-memory io.Reader's. Used -// for automatically sending the right Content-Length header when possible. -type LenReader interface { - Len() int -} - -// Request wraps the metadata needed to create HTTP requests. -type Request struct { - // body is a seekable reader over the request body payload. This is - // used to rewind the request data in between retries. - body ReaderFunc - - // Embed an HTTP request directly. This makes a *Request act exactly - // like an *http.Request so that all meta methods are supported. - *http.Request -} - -// WithContext returns wrapped Request with a shallow copy of underlying *http.Request -// with its context changed to ctx. The provided ctx must be non-nil. -func (r *Request) WithContext(ctx context.Context) *Request { - r.Request = r.Request.WithContext(ctx) - return r -} - -// NewRequest creates a new wrapped request. -func NewRequest(method, url string, rawBody interface{}) (*Request, error) { - var err error - var body ReaderFunc - var contentLength int64 - - if rawBody != nil { - switch rawBody.(type) { - // If they gave us a function already, great! Use it. - case ReaderFunc: - body = rawBody.(ReaderFunc) - tmp, err := body() - if err != nil { - return nil, err - } - if lr, ok := tmp.(LenReader); ok { - contentLength = int64(lr.Len()) - } - if c, ok := tmp.(io.Closer); ok { - c.Close() - } - - case func() (io.Reader, error): - body = rawBody.(func() (io.Reader, error)) - tmp, err := body() - if err != nil { - return nil, err - } - if lr, ok := tmp.(LenReader); ok { - contentLength = int64(lr.Len()) - } - if c, ok := tmp.(io.Closer); ok { - c.Close() - } - - // If a regular byte slice, we can read it over and over via new - // readers - case []byte: - buf := rawBody.([]byte) - body = func() (io.Reader, error) { - return bytes.NewReader(buf), nil - } - contentLength = int64(len(buf)) - - // If a bytes.Buffer we can read the underlying byte slice over and - // over - case *bytes.Buffer: - buf := rawBody.(*bytes.Buffer) - body = func() (io.Reader, error) { - return bytes.NewReader(buf.Bytes()), nil - } - contentLength = int64(buf.Len()) - - // We prioritize *bytes.Reader here because we don't really want to - // deal with it seeking so want it to match here instead of the - // io.ReadSeeker case. - case *bytes.Reader: - buf, err := ioutil.ReadAll(rawBody.(*bytes.Reader)) - if err != nil { - return nil, err - } - body = func() (io.Reader, error) { - return bytes.NewReader(buf), nil - } - contentLength = int64(len(buf)) - - // Compat case - case io.ReadSeeker: - raw := rawBody.(io.ReadSeeker) - body = func() (io.Reader, error) { - raw.Seek(0, 0) - return ioutil.NopCloser(raw), nil - } - if lr, ok := raw.(LenReader); ok { - contentLength = int64(lr.Len()) - } - - // Read all in so we can reset - case io.Reader: - buf, err := ioutil.ReadAll(rawBody.(io.Reader)) - if err != nil { - return nil, err - } - body = func() (io.Reader, error) { - return bytes.NewReader(buf), nil - } - contentLength = int64(len(buf)) - - default: - return nil, fmt.Errorf("cannot handle type %T", rawBody) - } - } - - httpReq, err := http.NewRequest(method, url, nil) - if err != nil { - return nil, err - } - httpReq.ContentLength = contentLength - - return &Request{body, httpReq}, nil -} - -// RequestLogHook allows a function to run before each retry. The HTTP -// request which will be made, and the retry number (0 for the initial -// request) are available to users. The internal logger is exposed to -// consumers. -type RequestLogHook func(*log.Logger, *http.Request, int) - -// ResponseLogHook is like RequestLogHook, but allows running a function -// on each HTTP response. This function will be invoked at the end of -// every HTTP request executed, regardless of whether a subsequent retry -// needs to be performed or not. If the response body is read or closed -// from this method, this will affect the response returned from Do(). -type ResponseLogHook func(*log.Logger, *http.Response) - -// CheckRetry specifies a policy for handling retries. It is called -// following each request with the response and error values returned by -// the http.Client. If CheckRetry returns false, the Client stops retrying -// and returns the response to the caller. If CheckRetry returns an error, -// that error value is returned in lieu of the error from the request. The -// Client will close any response body when retrying, but if the retry is -// aborted it is up to the CheckResponse callback to properly close any -// response body before returning. -type CheckRetry func(ctx context.Context, resp *http.Response, err error) (bool, error) - -// Backoff specifies a policy for how long to wait between retries. -// It is called after a failing request to determine the amount of time -// that should pass before trying again. -type Backoff func(min, max time.Duration, attemptNum int, resp *http.Response) time.Duration - -// ErrorHandler is called if retries are expired, containing the last status -// from the http library. If not specified, default behavior for the library is -// to close the body and return an error indicating how many tries were -// 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) - -// Client is used to make HTTP requests. It adds additional functionality -// like automatic retries to tolerate minor outages. -type Client struct { - HTTPClient *http.Client // Internal HTTP client. - Logger *log.Logger // Customer logger instance. - - RetryWaitMin time.Duration // Minimum time to wait - RetryWaitMax time.Duration // Maximum time to wait - RetryMax int // Maximum number of retries - - // RequestLogHook allows a user-supplied function to be called - // before each retry. - RequestLogHook RequestLogHook - - // ResponseLogHook allows a user-supplied function to be called - // with the response from each HTTP request executed. - ResponseLogHook ResponseLogHook - - // CheckRetry specifies the policy for handling retries, and is called - // after each request. The default policy is DefaultRetryPolicy. - CheckRetry CheckRetry - - // Backoff specifies the policy for how long to wait between retries - Backoff Backoff - - // ErrorHandler specifies the custom error handler to use, if any - ErrorHandler ErrorHandler -} - -// NewClient creates a new Client with default settings. -func NewClient() *Client { - return &Client{ - HTTPClient: cleanhttp.DefaultClient(), - Logger: log.New(os.Stderr, "", log.LstdFlags), - RetryWaitMin: defaultRetryWaitMin, - RetryWaitMax: defaultRetryWaitMax, - RetryMax: defaultRetryMax, - CheckRetry: DefaultRetryPolicy, - Backoff: DefaultBackoff, - } -} - -// DefaultRetryPolicy provides a default callback for Client.CheckRetry, which -// will retry on connection errors and server errors. -func DefaultRetryPolicy(ctx context.Context, resp *http.Response, err error) (bool, error) { - // do not retry on context.Canceled or context.DeadlineExceeded - if ctx.Err() != nil { - return false, ctx.Err() - } - - if err != nil { - return true, err - } - // Check the response code. We retry on 500-range responses to allow - // the server time to recover, as 500's are typically not permanent - // errors and may relate to outages on the server side. This will catch - // invalid response codes as well, like 0 and 999. - if resp.StatusCode == 0 || (resp.StatusCode >= 500 && resp.StatusCode != 501) { - return true, nil - } - - return false, nil -} - -// DefaultBackoff provides a default callback for Client.Backoff which -// will perform exponential backoff based on the attempt number and limited -// by the provided minimum and maximum durations. -func DefaultBackoff(min, max time.Duration, attemptNum int, resp *http.Response) time.Duration { - mult := math.Pow(2, float64(attemptNum)) * float64(min) - sleep := time.Duration(mult) - if float64(sleep) != mult || sleep > max { - sleep = max - } - return sleep -} - -// 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. -// -// min and max here are *not* absolute values. The number to be multipled by -// the attempt number will be chosen at random from between them, thus they are -// bounding the jitter. -// -// For instance: -// * To get strictly linear backoff of one second increasing each retry, set -// both to one second (1s, 2s, 3s, 4s, ...) -// * To get a small amount of jitter centered around one second increasing each -// retry, set to around one second, such as a min of 800ms and max of 1200ms -// (892ms, 2102ms, 2945ms, 4312ms, ...) -// * To get extreme jitter, set to a very wide spread, such as a min of 100ms -// and a max of 20s (15382ms, 292ms, 51321ms, 35234ms, ...) -func LinearJitterBackoff(min, max time.Duration, attemptNum int, resp *http.Response) time.Duration { - // attemptNum always starts at zero but we want to start at 1 for multiplication - attemptNum++ - - if max <= min { - // Unclear what to do here, or they are the same, so return min * - // attemptNum - return min * time.Duration(attemptNum) - } - - // Seed rand; doing this every time is fine - rand := 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) - jitterMin := int64(jitter) + int64(min) - return time.Duration(jitterMin * int64(attemptNum)) -} - -// PassthroughErrorHandler is an ErrorHandler that directly passes through the -// values from the net/http library for the final request. The body is not -// closed. -func PassthroughErrorHandler(resp *http.Response, err error, _ int) (*http.Response, error) { - return resp, err -} - -// Do wraps calling an HTTP method with retries. -func (c *Client) Do(req *Request) (*http.Response, error) { - if c.Logger != nil { - c.Logger.Printf("[DEBUG] %s %s", req.Method, req.URL) - } - - var resp *http.Response - var err error - - for i := 0; ; i++ { - var code int // HTTP response code - - // Always rewind the request body when non-nil. - if req.body != nil { - body, err := req.body() - if err != nil { - return resp, err - } - if c, ok := body.(io.ReadCloser); ok { - req.Request.Body = c - } else { - req.Request.Body = ioutil.NopCloser(body) - } - } - - if c.RequestLogHook != nil { - c.RequestLogHook(c.Logger, req.Request, i) - } - - // Attempt the request - resp, err = c.HTTPClient.Do(req.Request) - if resp != nil { - code = resp.StatusCode - } - - // Check if we should continue with retries. - checkOK, checkErr := c.CheckRetry(req.Request.Context(), resp, err) - - if err != nil { - if c.Logger != nil { - c.Logger.Printf("[ERR] %s %s request failed: %v", req.Method, req.URL, err) - } - } else { - // Call this here to maintain the behavior of logging all requests, - // even if CheckRetry signals to stop. - if c.ResponseLogHook != nil { - // Call the response logger function if provided. - c.ResponseLogHook(c.Logger, resp) - } - } - - // Now decide if we should continue. - if !checkOK { - if checkErr != nil { - err = checkErr - } - return resp, err - } - - // We do this before drainBody beause there's no need for the I/O if - // we're breaking out - remain := c.RetryMax - i - if remain <= 0 { - break - } - - // We're going to retry, consume any response to reuse the connection. - if err == nil && resp != nil { - c.drainBody(resp.Body) - } - - wait := c.Backoff(c.RetryWaitMin, c.RetryWaitMax, i, resp) - desc := fmt.Sprintf("%s %s", req.Method, req.URL) - if code > 0 { - desc = fmt.Sprintf("%s (status: %d)", desc, code) - } - if c.Logger != nil { - c.Logger.Printf("[DEBUG] %s: retrying in %s (%d left)", desc, wait, remain) - } - time.Sleep(wait) - } - - if c.ErrorHandler != nil { - return c.ErrorHandler(resp, err, c.RetryMax+1) - } - - // By default, we close the response body and return an error without - // returning the response - if resp != nil { - resp.Body.Close() - } - return nil, fmt.Errorf("%s %s giving up after %d attempts", - req.Method, req.URL, c.RetryMax+1) -} - -// 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)) - if err != nil { - if c.Logger != nil { - c.Logger.Printf("[ERR] error reading response body: %v", err) - } - } -} - -// Get is a shortcut for doing a GET request without making a new client. -func Get(url string) (*http.Response, error) { - return defaultClient.Get(url) -} - -// Get is a convenience helper for doing simple GET requests. -func (c *Client) Get(url string) (*http.Response, error) { - req, err := NewRequest("GET", url, nil) - if err != nil { - return nil, err - } - return c.Do(req) -} - -// Head is a shortcut for doing a HEAD request without making a new client. -func Head(url string) (*http.Response, error) { - return defaultClient.Head(url) -} - -// Head is a convenience method for doing simple HEAD requests. -func (c *Client) Head(url string) (*http.Response, error) { - req, err := NewRequest("HEAD", url, nil) - if err != nil { - return nil, err - } - return c.Do(req) -} - -// Post is a shortcut for doing a POST request without making a new client. -func Post(url, bodyType string, body interface{}) (*http.Response, error) { - return defaultClient.Post(url, bodyType, body) -} - -// Post is a convenience method for doing simple POST requests. -func (c *Client) Post(url, bodyType string, body interface{}) (*http.Response, error) { - req, err := NewRequest("POST", url, body) - if err != nil { - return nil, err - } - req.Header.Set("Content-Type", bodyType) - return c.Do(req) -} - -// PostForm is a shortcut to perform a POST with form data without creating -// a new client. -func PostForm(url string, data url.Values) (*http.Response, error) { - return defaultClient.PostForm(url, data) -} - -// PostForm is a convenience method for doing simple POST operations using -// pre-filled url.Values form data. -func (c *Client) PostForm(url string, data url.Values) (*http.Response, error) { - return c.Post(url, "application/x-www-form-urlencoded", strings.NewReader(data.Encode())) -} -- cgit v1.2.3