feat: apply markdown rendering to HITL email, sanitize email subject and body by Blackoutta · Pull Request #32305 · langgenius/dify

Blackoutta · 2026-02-13T07:48:31Z

Summary

Add NH3-based sanitization for human-input email HTML with strict/balanced/free profiles.
Apply sanitization in both test-send and background mail task paths.
Harden subject handling by stripping ASCII control characters (except tab).
Add unit tests for sanitizer behavior and update mail config docs.
Dependency: nh3~=0.3.2.

Checklist

This change requires a documentation update, included: Dify Document
I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
I've updated the documentation accordingly.
I ran make lint and make type-check (backend) and cd web && npx lint-staged (frontend) to appease the lint gods

gemini-code-assist · 2026-02-13T07:48:57Z

Summary of Changes

Hello @Blackoutta, 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 significantly enhances the security posture of outbound emails by integrating robust HTML and subject sanitization. It addresses potential vulnerabilities arising from untrusted HTML content in emails by introducing configurable sanitization profiles, ensuring that only safe and intended elements are delivered to recipients. This change improves the integrity and safety of email communications within the system.

Highlights

Email HTML Sanitization: Introduced NH3-based HTML sanitization for outbound emails, offering 'strict', 'balanced', and 'free' profiles to control allowed tags, attributes, and URL schemes.
Subject Hardening: Implemented email subject hardening by stripping most ASCII control characters (except tab) to prevent injection attacks.
Sanitization Application: Applied both HTML and subject sanitization to email content in test-send functionality and background mail tasks, ensuring consistent security.
New Dependency & Configuration: Added nh3~=0.3.2 as a new dependency and introduced MAIL_HTML_SANITIZER_PROFILE configuration option in environment files and Docker Compose.
Unit Testing: Added comprehensive unit tests to validate the behavior of the new HTML and subject sanitization logic across different profiles and malicious inputs.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

Changelog

api/.env.example
- Added a new environment variable MAIL_HTML_SANITIZER_PROFILE with a default of balanced to configure email HTML sanitization.
api/configs/feature/init.py
- Defined MailHtmlSanitizerProfile enum with STRICT, BALANCED, and FREE options.
- Integrated MAIL_HTML_SANITIZER_PROFILE into the MailConfig class with a default value of BALANCED.
api/libs/email_html_sanitizer.py
- Created a new module containing functions sanitize_email_html and sanitize_email_subject.
- Implemented nh3-based HTML cleaning logic with predefined strict and balanced profiles.
- Added logic to strip control characters from email subjects.
api/pyproject.toml
- Added nh3~=0.3.2 to the project's dependencies.
api/services/human_input_delivery_test_service.py
- Imported sanitize_email_html and sanitize_email_subject functions.
- Updated the send_test function to apply sanitization to the email subject and body before sending test emails.
api/tasks/mail_human_input_delivery_task.py
- Imported sanitize_email_html and sanitize_email_subject functions.
- Modified the dispatch_human_input_email_task to sanitize both the subject and HTML body of emails before dispatching them.
api/tests/unit_tests/libs/test_email_html_sanitizer.py
- Added a new test file with unit tests covering various scenarios for HTML and subject sanitization.
- Included tests for stripping scripts, event handlers, JavaScript URLs, and control characters, and verifying allowed content.
api/tests/unit_tests/services/test_human_input_delivery_test_service.py
- Added a new test case to verify that the email delivery test handler correctly sanitizes HTML content based on the configured profile.
api/uv.lock
- Updated the dependency lock file to include the nh3 package and its associated metadata.
docker/.env.example
- Added MAIL_HTML_SANITIZER_PROFILE with a default value of balanced to the Docker environment example.
docker/docker-compose.yaml
- Included MAIL_HTML_SANITIZER_PROFILE in the x-shared-env section for API and worker services, defaulting to balanced.

Activity

No human activity has been recorded on this pull request yet.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	`/gemini review`	Performs a code review for the current pull request in its current state.
Pull Request Summary	`/gemini summary`	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	`/gemini help`	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

gemini-code-assist

Code Review

This pull request introduces robust HTML sanitization for emails using the nh3 library and hardens email subject handling, providing strong security against XSS and CRLF injection attacks. While no critical security vulnerabilities were identified, there is a critical bug in the background task where the email subject is not rendered, causing template variables to be ignored. Further improvements include making the sanitize_email_subject function more concise and clarifying misleading test names in the new unit tests. The critical bug in the mail task must be addressed before merging.

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

…while resuming

Manipulate sys.path inside test making test fragile and hard to reason. Instead of manully append / prepend sys.path, we set the `pythonpath` option for pytest, so the PYTHONPATH and import path are automatically determined by the location of `pytest.ini`. We also set the `--import-mode` to `importlib` to prevent pytest from prepending paths to sys.path. ref: - [pytest import mechanisms and sys.path/PYTHONPATH](https://docs.pytest.org/en/stable/explanation/pythonpath.html#pythonpath) - [Initialization: determining rootdir and configfile](https://docs.pytest.org/en/stable/reference/customize.html#finding-the-rootdir)

remove unused import in test code

…l-bod

…il-bod

github-actions · 2026-03-16T07:55:45Z

Pyrefly Diff

No changes detected.

QuantumGhost · 2026-03-16T08:06:52Z

Hi @Blackoutta, I have revised the PR and introduced markdown rendering as part of the PR. I've also added SMTP header injection protection to this PR.

github-actions · 2026-03-16T08:12:28Z

Pyrefly Diff

No changes detected.

Blackoutta · 2026-03-16T08:19:44Z

Hi @Blackoutta, I have revised the PR and introduced markdown rendering as part of the PR. I've also added SMTP header injection protection to this PR.

awesome!

feat: Add email HTML sanitization profiles

bea62a5

Blackoutta requested review from QuantumGhost and laipz8200 as code owners February 13, 2026 07:48

dosubot Bot added size:L This PR changes 100-499 lines, ignoring generated files. 💪 enhancement New feature or request labels Feb 13, 2026

Merge branch 'main' into feature/add-email-sanitization

e35200e

gemini-code-assist Bot reviewed Feb 13, 2026

View reviewed changes

Comment thread api/tasks/mail_human_input_delivery_task.py Outdated

Comment thread api/libs/email_html_sanitizer.py Outdated

Comment thread api/tests/unit_tests/libs/test_email_html_sanitizer.py Outdated

Comment thread api/tests/unit_tests/libs/test_email_html_sanitizer.py Outdated

Blackoutta marked this pull request as draft February 13, 2026 07:54

Blackoutta and others added 2 commits February 13, 2026 16:02

Update api/libs/email_html_sanitizer.py

2c16e54

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

fix: email sanitizer unit test names

b300afa

Blackoutta marked this pull request as ready for review February 13, 2026 08:33

Blackoutta and others added 12 commits February 13, 2026 17:28

Merge branch 'main' into feature/add-email-sanitization

9aa7e8c

Merge branch 'main' into feature/add-email-sanitization

9b5afb2

Merge branch 'main' into feature/add-email-sanitization

b977987

fix(api): fix the issue that workflow_runs.started_at is overwritten …

ed85979

…while resuming

[autofix.ci] apply automated fixes

9686b7c

test(api): fix broken test

425d585

[autofix.ci] apply automated fixes

424fd94

test(api): remove uncessary try ... except inside conftest.py

aa8671b

remove unused import in test code

chore(api): log the url used for offline migration sql generation

e29f1fd

test(api): Update import path for workflow related types

ef12b75

[autofix.ci] apply automated fixes

b5471ca

QuantumGhost removed the request for review from laipz8200 March 16, 2026 02:47

QuantumGhost added 2 commits March 16, 2026 11:04

feat(hitl-email): render markdown body and sanitize html with bleach

9c44374

refactor(hitl-email): restrict markdown html allowlist to basic tags

f5ad0d0

QuantumGhost mentioned this pull request Mar 16, 2026

[Tracker] 1.13.1 release blockers #33478

Closed

10 tasks

refactor(hitl-email): strip raw html before markdown rendering

04493aa

QuantumGhost marked this pull request as draft March 16, 2026 06:10

QuantumGhost added 7 commits March 16, 2026 14:16

feat(hitl-email): enable gfm table rendering with bleach sanitization

2f67593

test(hitl-email): cover javascript markdown link sanitization

dc83660

Merge remote-tracking branch 'upstream/main' into vk/3a78-render-emai…

a07dd25

…l-bod

Merge remote-tracking branch 'upstream/main' into vk/3a78-render-emai…

8d694f9

…l-bod

Merge branch 'feature/add-email-sanitization' into vk/3a78-render-ema…

4aecf8b

…il-bod

security(hitl-email): sanitize subject against CRLF and html injection

e70bf57

test(hitl-email): cover subject sanitization for standalone CR and LF

9f246d3

QuantumGhost marked this pull request as ready for review March 16, 2026 07:54

fatelei approved these changes Mar 16, 2026

View reviewed changes

dosubot Bot added the lgtm This PR has been approved by a maintainer label Mar 16, 2026

Merge branch 'main' into feature/add-email-sanitization

1909012

QuantumGhost changed the title ~~feat: Add email HTML sanitization profiles~~ feat: apply markdown rendering to email , sanitize email subject and body Mar 16, 2026

QuantumGhost changed the title ~~feat: apply markdown rendering to email , sanitize email subject and body~~ feat: apply markdown rendering to HITL email, sanitize email subject and body Mar 16, 2026

QuantumGhost merged commit 57d476d into langgenius:main Mar 16, 2026
19 checks passed

pgs-bot Bot mentioned this pull request Mar 18, 2026

Update Dify to v1.13.1 progamesigner/manifests#790

Merged

dosubot Bot mentioned this pull request Mar 26, 2026

Human Input email delivery can generate broken form links when {{#url#}} is adjacent to text #34160

Open

6 tasks

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

feat: apply markdown rendering to HITL email, sanitize email subject and body#32305

feat: apply markdown rendering to HITL email, sanitize email subject and body#32305
QuantumGhost merged 27 commits intolanggenius:mainfrom
Blackoutta:feature/add-email-sanitization

Blackoutta commented Feb 13, 2026 •

edited by QuantumGhost

Loading

Uh oh!

gemini-code-assist Bot commented Feb 13, 2026

Uh oh!

gemini-code-assist Bot left a comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

github-actions Bot commented Mar 16, 2026

Uh oh!

QuantumGhost commented Mar 16, 2026 •

edited

Loading

Uh oh!

github-actions Bot commented Mar 16, 2026

Uh oh!

Blackoutta commented Mar 16, 2026

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Conversation

Blackoutta commented Feb 13, 2026 • edited by QuantumGhost Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Checklist

Uh oh!

gemini-code-assist Bot commented Feb 13, 2026

Summary of Changes

Highlights

Footnotes

Uh oh!

gemini-code-assist Bot left a comment

Choose a reason for hiding this comment

Code Review

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

github-actions Bot commented Mar 16, 2026

Pyrefly Diff

Uh oh!

QuantumGhost commented Mar 16, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

github-actions Bot commented Mar 16, 2026

Pyrefly Diff

Uh oh!

Blackoutta commented Mar 16, 2026

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Blackoutta commented Feb 13, 2026 •

edited by QuantumGhost

Loading

QuantumGhost commented Mar 16, 2026 •

edited

Loading