🐛 bug: Fix multipart boundary for Client per RFC 2046 by gaby · Pull Request #3563 · gofiber/fiber

gaby · 2025-07-03T12:23:43Z

Summary

remove leading dashes from default multipart boundary in client
update tests for new boundary formatting

Related #3383

coderabbitai · 2025-07-03T12:23:49Z

Walkthrough

The changes update the default multipart boundary string in the client package by removing leading dashes from its value. Associated test assertions and regular expressions are also adjusted to reflect the new boundary format, ensuring consistency across the codebase and tests.

Changes

Files	Change Summary
client/core.go, client/request.go	Updated the default multipart boundary string by removing leading dashes from its value.
client/hooks_test.go	Adjusted test assertions to match the new boundary string format in multipart header and body.
client/request_test.go	Modified regex in test to expect a 33-character boundary, aligning with the updated format.

Suggested labels

🧹 Updates, v3

Suggested reviewers

sixcolors
nickajacks1
ReneWerner87

Poem

A boundary once wore dashes bold,
But now its tale is simply told—
Stripped of lines, it stands with pride,
In headers, tests, and code beside.
The rabbits cheer this tidy feat,
For cleaner strings are hard to beat!
🐇✨

📜 Recent review details

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 01d8543 and d5eea38.

📒 Files selected for processing (4)

client/core.go (1 hunks)
client/hooks_test.go (3 hunks)
client/request.go (1 hunks)
client/request_test.go (1 hunks)

🧰 Additional context used

🧠 Learnings (5)

📓 Common learnings

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Feature request #3224 has been created to add support for square bracket notation and comma-separated values in multipart form data in Fiber, while maintaining binary data transfer capabilities. This would bring parity with the existing form-urlencoded functionality.

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Fiber currently supports square bracket notation in form data with 'application/x-www-form-urlencoded' content type, but this feature is not available for multipart form data. The implementation for form-urlencoded is in ctx.go (BodyParser method), while multipart form data handling needs enhancement to support this feature.

Learnt from: ReneWerner87
PR: gofiber/fiber#3161
File: app.go:923-932
Timestamp: 2024-11-15T07:56:21.623Z
Learning: In the Fiber framework, breaking changes are acceptable when moving from version 2 to version 3, including modifications to method signatures such as in the `Test` method in `app.go`.

client/request_test.go (5)

Learnt from: gaby
PR: gofiber/fiber#3170
File: ctx_test.go:1721-1724
Timestamp: 2024-10-16T12:12:30.506Z
Learning: In the Go unit tests in `ctx_test.go`, it is acceptable to use invalid CIDR notation such as `"0.0.0.1/31junk"` for testing purposes.

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Fiber currently supports square bracket notation in form data with 'application/x-www-form-urlencoded' content type, but this feature is not available for multipart form data. The implementation for form-urlencoded is in ctx.go (BodyParser method), while multipart form data handling needs enhancement to support this feature.

Learnt from: ReneWerner87
PR: gofiber/fiber#3161
File: app.go:923-932
Timestamp: 2024-11-15T07:56:21.623Z
Learning: In the Fiber framework, breaking changes are acceptable when moving from version 2 to version 3, including modifications to method signatures such as in the `Test` method in `app.go`.

Learnt from: gaby
PR: gofiber/fiber#3056
File: middleware/encryptcookie/utils.go:22-25
Timestamp: 2024-07-02T13:29:56.992Z
Learning: The `encryptcookie_test.go` file contains unit tests that validate key lengths for both `EncryptCookie` and `DecryptCookie` functions, ensuring that invalid key lengths raise appropriate errors.

Learnt from: gaby
PR: gofiber/fiber#3056
File: middleware/encryptcookie/utils.go:22-25
Timestamp: 2024-10-08T19:06:06.583Z
Learning: The `encryptcookie_test.go` file contains unit tests that validate key lengths for both `EncryptCookie` and `DecryptCookie` functions, ensuring that invalid key lengths raise appropriate errors.

client/core.go (3)

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Fiber currently supports square bracket notation in form data with 'application/x-www-form-urlencoded' content type, but this feature is not available for multipart form data. The implementation for form-urlencoded is in ctx.go (BodyParser method), while multipart form data handling needs enhancement to support this feature.

Learnt from: ReneWerner87
PR: gofiber/fiber#3161
File: app.go:923-932
Timestamp: 2024-11-15T07:56:21.623Z
Learning: In the Fiber framework, breaking changes are acceptable when moving from version 2 to version 3, including modifications to method signatures such as in the `Test` method in `app.go`.

Learnt from: gaby
PR: gofiber/fiber#3193
File: middleware/adaptor/adaptor.go:111-111
Timestamp: 2024-11-10T23:44:13.704Z
Learning: In the `middleware/adaptor/adaptor.go` file of the Fiber framework, when updating context handling, replacing `c.Context()` with `c.RequestCtx()` is appropriate to access the `fasthttp.RequestCtx`.

client/hooks_test.go (14)

Learnt from: ReneWerner87
PR: gofiber/fiber#3161
File: app.go:923-932
Timestamp: 2024-11-15T07:56:21.623Z
Learning: In the Fiber framework, breaking changes are acceptable when moving from version 2 to version 3, including modifications to method signatures such as in the `Test` method in `app.go`.

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Fiber currently supports square bracket notation in form data with 'application/x-www-form-urlencoded' content type, but this feature is not available for multipart form data. The implementation for form-urlencoded is in ctx.go (BodyParser method), while multipart form data handling needs enhancement to support this feature.

Learnt from: sixcolors
PR: gofiber/fiber#3016
File: middleware/csrf/csrf_test.go:188-193
Timestamp: 2024-10-08T19:06:06.583Z
Learning: In the Fiber framework tests, using `ctx.Response.Header.Cookie` may not be suitable for parsing cookies from the response header, as it requires a `*Cookie` and fills it rather than returning a string value; thus, manual parsing of the `Set-Cookie` header may be necessary.

Learnt from: sixcolors
PR: gofiber/fiber#3016
File: middleware/csrf/csrf_test.go:188-193
Timestamp: 2024-09-25T15:57:10.221Z
Learning: In the Fiber framework tests, using `ctx.Response.Header.Cookie` may not be suitable for parsing cookies from the response header, as it requires a `*Cookie` and fills it rather than returning a string value; thus, manual parsing of the `Set-Cookie` header may be necessary.

Learnt from: sixcolors
PR: gofiber/fiber#2922
File: middleware/cors/utils.go:63-71
Timestamp: 2024-07-26T21:00:12.902Z
Learning: The project uses the testify/assert package for assertions in unit tests.

Learnt from: sixcolors
PR: gofiber/fiber#2922
File: middleware/cors/utils.go:63-71
Timestamp: 2024-10-08T19:06:06.583Z
Learning: The project uses the testify/assert package for assertions in unit tests.

Learnt from: efectn
PR: gofiber/fiber#3162
File: hooks_test.go:228-228
Timestamp: 2024-12-13T08:14:22.851Z
Learning: In Go test files, prefer using the `require` methods from the `testify` package for assertions instead of manual comparisons and calls to `t.Fatal` or `t.Fatalf`.

Learnt from: gaby
PR: gofiber/fiber#3170
File: ctx_test.go:1721-1724
Timestamp: 2024-10-16T12:12:30.506Z
Learning: In the Go unit tests in `ctx_test.go`, it is acceptable to use invalid CIDR notation such as `"0.0.0.1/31junk"` for testing purposes.

Learnt from: sixcolors
PR: gofiber/fiber#3051
File: middleware/session/session.go:215-216
Timestamp: 2024-06-30T00:38:06.580Z
Learning: Parallel tests for `Session.Save` already exist in the `middleware/session/session_test.go` file, specifically in the `Test_Session_Save` and `Test_Session_Save_Expiration` functions.

Learnt from: sixcolors
PR: gofiber/fiber#3051
File: middleware/session/session.go:215-216
Timestamp: 2024-10-08T19:06:06.583Z
Learning: Parallel tests for `Session.Save` already exist in the `middleware/session/session_test.go` file, specifically in the `Test_Session_Save` and `Test_Session_Save_Expiration` functions.

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Feature request #3224 has been created to add support for square bracket notation and comma-separated values in multipart form data in Fiber, while maintaining binary data transfer capabilities. This would bring parity with the existing form-urlencoded functionality.

Learnt from: gaby
PR: gofiber/fiber#3193
File: middleware/adaptor/adaptor.go:111-111
Timestamp: 2024-11-10T23:44:13.704Z
Learning: In the `middleware/adaptor/adaptor.go` file of the Fiber framework, when updating context handling, replacing `c.Context()` with `c.RequestCtx()` is appropriate to access the `fasthttp.RequestCtx`.

Learnt from: sixcolors
PR: gofiber/fiber#3016
File: middleware/session/store.go:164-167
Timestamp: 2024-10-02T23:03:31.727Z
Learning: Unit tests in this project use testify require.

Learnt from: sixcolors
PR: gofiber/fiber#3016
File: middleware/session/store.go:164-167
Timestamp: 2024-10-08T19:06:06.583Z
Learning: Unit tests in this project use testify require.

client/request.go (4)

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Fiber currently supports square bracket notation in form data with 'application/x-www-form-urlencoded' content type, but this feature is not available for multipart form data. The implementation for form-urlencoded is in ctx.go (BodyParser method), while multipart form data handling needs enhancement to support this feature.

Learnt from: gaby
PR: gofiber/fiber#3193
File: middleware/cache/cache_test.go:897-897
Timestamp: 2024-11-08T04:10:42.990Z
Learning: In the Fiber framework, `Context()` is being renamed to `RequestCtx()`, and `UserContext()` to `Context()` to improve clarity and align with Go's context conventions.

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Feature request #3224 has been created to add support for square bracket notation and comma-separated values in multipart form data in Fiber, while maintaining binary data transfer capabilities. This would bring parity with the existing form-urlencoded functionality.

Learnt from: gaby
PR: gofiber/fiber#3193
File: middleware/adaptor/adaptor.go:111-111
Timestamp: 2024-11-10T23:44:13.704Z
Learning: In the `middleware/adaptor/adaptor.go` file of the Fiber framework, when updating context handling, replacing `c.Context()` with `c.RequestCtx()` is appropriate to access the `fasthttp.RequestCtx`.

🔇 Additional comments (5)

client/core.go (1)

17-17: LGTM! Boundary format correction.

Removing the leading dashes from the boundary variable is correct. According to RFC 2046, the boundary parameter in the Content-Type header should not include the leading dashes - those are added by the multipart writer when delimiting parts in the message body.

client/request.go (1)

941-941: LGTM! Consistent boundary format.

The boundary initialization in the request pool now matches the corrected format from core.go, ensuring consistency across the client package.

client/request_test.go (1)

1335-1335: LGTM! Boundary length validation updated correctly.

The regex pattern correctly adjusts the expected boundary length from 35 to 33 characters, accounting for the removal of the 2 leading dashes from the boundary format.

client/hooks_test.go (2)

301-301: LGTM! Header boundary validation corrected.

The test now correctly expects the boundary without leading dashes in the Content-Type header, which aligns with RFC 2046 multipart specifications.

517-517: LGTM! Body boundary validation corrected.

The tests now correctly expect --FiberFormBoundary in the multipart body content, which is the proper format where the multipart writer adds exactly two leading dashes to delimit message parts.

Also applies to: 530-530

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gemini-code-assist

Summary of Changes

Hello @gaby, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request refines the client's handling of multipart form data by correcting the default boundary string format. The primary goal is to ensure compliance with multipart specifications, which dictates that the boundary string itself should not include the leading hyphens, as these are part of the delimiter used within the message body. Accompanying test updates validate this corrected behavior.

Highlights

Multipart Boundary Standardization: The default multipart boundary string used by the client has been updated to remove the leading double dashes (--). This change ensures the boundary string itself is FiberFormBoundary, with the RFC 2046 required leading dashes being part of the delimiter in the message body, not the boundary definition.
Test Suite Alignment: All relevant test cases have been adjusted to reflect the new boundary format. This includes updates to assertions checking the MultipartFormBoundary() in headers, the RawRequest.Body() content, and the regex pattern used to validate the length of the boundary in the Content-Type header.

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Copilot

Pull Request Overview

This PR removes the leading dashes from the default multipart boundary in the client implementation and updates tests to match the new boundary format.

Drop -- prefix from the default boundary variable.
Update tests to expect the shorter boundary (length minus two hyphens).
Adjust regex and literal checks in request and hooks tests.

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
client/request.go	Removed leading dashes from default boundary
client/core.go	Updated global `boundary` var without `--`
client/request_test.go	Adjusted regex from `{35}` to `{33}` for boundary length
client/hooks_test.go	Updated literal expectations for multipart boundaries

client/request_test.go

client/hooks_test.go

gemini-code-assist

Code Review

This pull request fixes an issue with multipart form boundaries by removing the prepended dashes from the default boundary value. The associated tests have been updated to reflect this fix.

client/request.go

🩹 Fix: remove leading dashes from multipart boundary

d5eea38

Copilot AI review requested due to automatic review settings July 3, 2025 12:23

gaby added the codex label Jul 3, 2025 — with ChatGPT Codex Connector

gaby requested a review from a team as a code owner July 3, 2025 12:23

gaby requested review from ReneWerner87, efectn and sixcolors July 3, 2025 12:23

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gaby added ☢️ Bug v3 labels Jul 3, 2025

gaby added this to v3 Jul 3, 2025

gaby added this to the v3 milestone Jul 3, 2025

gaby moved this to In Progress in v3 Jul 3, 2025

Copilot AI reviewed Jul 3, 2025

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client/request_test.go Show resolved Hide resolved

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gaby changed the title ~~Fix multipart boundary for client~~ 🐛 bug: Fix multipart boundary for client Jul 3, 2025

gaby changed the title ~~🐛 bug: Fix multipart boundary for client~~ 🐛 bug: Fix multipart boundary for Client Jul 3, 2025

gemini-code-assist bot reviewed Jul 3, 2025

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gaby changed the title ~~🐛 bug: Fix multipart boundary for Client~~ 🐛 bug: Fix multipart boundary for Client per RFC 2046 Jul 3, 2025

ReneWerner87 approved these changes Jul 3, 2025

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ReneWerner87 merged commit 10e92eb into main Jul 3, 2025
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github-project-automation bot moved this from In Progress to Done in v3 Jul 3, 2025

gaby deleted the 2025-07-03-12-23-39 branch July 3, 2025 21:16

coderabbitai bot mentioned this pull request Oct 5, 2025

🧹 chore: make boundary a const #3783

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gaby added the 📜 RFC Compliance Feature, implementation, or contribution adheres to relevant RFC standards. label Nov 27, 2025

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🐛 bug: Fix multipart boundary for Client per RFC 2046#3563

🐛 bug: Fix multipart boundary for Client per RFC 2046#3563
ReneWerner87 merged 1 commit intomainfrom
2025-07-03-12-23-39

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