[CT-02] Implement revoke_document handler

[mftee]

Problem

The POST /revoke endpoint returns a hardcoded NOT_FOUND with not yet implemented. There is no way to record that a previously anchored document has been revoked, which is a required step in the document lifecycle.

Proposed Solution

Implement the revoke_document handler inside contract/module/revoke/. The revocation must be anchored on Stellar and recorded in Redis so that downstream systems can detect revoked documents.

Acceptance Criteria

• Handler validates the document_hash using HashValidator::validate_sha256
• Checks Redis for an existing revocation record — if one already exists returns 409 with a already revoked error
• Anchors the revocation event on Stellar using StellarClient with a memo containing REVOKE: and the first 20 characters of the hash
• Stores the revocation record in Redis under key revoke:{document_hash} with fields: reason, revoked_by, txHash, and revoked_at (Unix timestamp)
• Returns 200 with a RevokeResponse containing transaction_id and revoked_at
• Returns 400 for invalid hash format
• Implementation files live inside contract/module/revoke/

[NEA-DEV-coder]

@NEA-DEV-coder has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi , I am a smart contract developer proficient with stellar contract, I believe i can handle this issue. ETA 2hrs

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[shadrach68]

@shadrach68 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi maintainer, I'd like to work on this issue. Can you assign?

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[AGWAM001]

@AGWAM001 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Please assign will work it out very fast

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[Ejirowebfi]

@Ejirowebfi has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi maintainers, I'd like to work on this issue.

I'm a Full Stack Developer with experience across the entire stack — from pixel-accurate frontend UIs to scalable backend APIs and database design. I've shipped production-ready features using Next.js/React + Tailwind on the frontend, and Node.js/Express, PostgreSQL, and REST/GraphQL APIs on the backend.

What I'll deliver

• Component/feature implemented to match the design/spec
• Responsive behavior (mobile + desktop), no layout breakage
• Hover/focus states + accessible semantics
• Clean, reusable components and consistent styling
• RESTful or GraphQL API endpoints (if applicable)
• Database schema design or migrations (if applicable)
• Authentication, authorization, and data validation where needed

Approach

1. Review the design/spec, existing code patterns, and any relevant API contracts
2. Build the UI + interactions on the frontend
3. Implement or update backend logic, routes, and data models as needed
4. Write unit/integration tests for critical paths
5. QA on multiple breakpoints + open a PR with screenshots/video and a summary of backend changes

Stack
Frontend: Next.js · React · TypeScript · Tailwind CSS
Backend: Node.js · Express · PostgreSQL · Prisma / Drizzle
Infra: REST · GraphQL · JWT Auth · Docker · Vercel / Railway

If assigned, I'll start immediately and share progress updates in the PR.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Ejirowebfi to this issue.

[Michealshodipo56]

@Michealshodipo56 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

i would like to work on this kindly assign me

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[Sadeequ]

@Sadeequ has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi maintaintainer let me get on this for you, it is similar to the issue i solved earlier. I can implement this and improve performance of the other subroutine i pushed Sir.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Sadeequ to this issue.

[drips-wave]

Congratulations, @Sadeequ! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @Sadeequ: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊