feat: sign usign twofactor_gateway

[vitormattos]

Objective

Allow requesting a document signature by adding a WhatsApp number (or another configured gateway) and sending the signing link directly to this number.

⚠️ For WhatsApp, this implementation uses WhatsApp Web and not the WhatsApp Business API.

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How to test

• Install the twofactor_gateway app.
  • For now will be necessary to use the master branch of this app.
• Configure a gateway (e.g., WhatsApp or SMS).
• Go to LibreSign Administration Settings.
• Enable the signature method related to the configured provider in Twofactor Gateway.
  • Only the providers that are configured will appear as signature methods.
• Follow the usual steps to request a document signature.

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Administration settings

Only the gateways configured in the Twofactor Gateway app will be visible.

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Sign request flow

• The Add signer screen has been improved for a better UX and now is a dialog.
• Signature methods are now organized into tabs.
• Only the identity methods enabled in Administration Settings will be shown.

👉 Don’t worry about the number of tabs, in most scenarios there will be no more than three. For demonstration purposes, all available methods were enabled to show compatibility with multiple signature request options.

• The chosen signature method will now appear as a label under the signer’s name.

• After finishing the sign request flow, the signer will receive the signing link via the selected service:

To-do

• Implement unit tests
• Implement integration tests
• Add a new gateway to sign with Telegram at Twofactor Gateway but now using the client API of Telegram

[backportbot-libresign]

The backport to stable32 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable32
git pull origin stable32

# Create the new backport branch
git checkout -b backport/5459/stable32

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 36d259c5 4c843ae8 5a5f4d26 10898291 a795fbf1 28875646 02c1d605 d3660d41 9858fe58 260c0574 1add24e3 d3e123f0 346ec72a 67f789f9 b4535c3c 005cf495 89ef1412 56d03a7a e5d08b57 d85b0b92 e9d82fca 2b5436ae aaec06f0 5ff83601 e74af514 fbc1f1d5 fd4be101 aa15d265 e36196ba 568c1d82

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/5459/stable32

Error: Failed to push branch backport/5459/stable32: fatal: could not read Username for 'https://github.com': No such device or address

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Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.