Add zkSync Checkout

[mds1]

This is currently a draft PR, but the core functionality has been implemented so I think this is a good time for an initial review

Instructions for testing

1. zkSync has test tokens for Rinkeby that anyone can mint. The full list of supported Rinkeby tokens can be found here, but only a subset have been added to Gitcoin. Mint yourself the below tokens:

   • USDT, 6 decimals, located at 0x3b00ef435fa4fcff5c209a37d1f3dcff37c705ad
   • LINK, 18 decimals, located at 0x4da8d0795830f75be471f072a034d42c369b5d0a
   • You'll see I added Rinkeby USDC to the economy model, but for some reason Gitcoin doesn't seem to recognize that, so just use the above two

2. Then, add some grants to your cart

3. Choose any mix of ETH, USDT, and LINK for your grants. For now, don't use token amounts below 0.5 to ensure the amount is packable. (We'll handle this more robustly later. For more info see here and here in the zkSync docs.)

4. Click "Checkout with zkSync" and follow the steps

cc @danlipert @octavioamu @thelostone-mc @apbendi @owocki

[mds1]

The checkout modal shown in these Figma mockups has now been implemented, so you no longer have to rely on console messages to see status updates

[codecov]

Codecov Report

Merging #7314 into round-7-integration will decrease coverage by 0.08%.
The diff coverage is 11.25%.

@@                   Coverage Diff                   @@
##           round-7-integration    #7314      +/-   ##
=======================================================
- Coverage                26.47%   26.38%   -0.09%     
=======================================================
  Files                      303      306       +3     
  Lines                    29996    30211     +215     
  Branches                  4430     4461      +31     
=======================================================
+ Hits                      7942     7972      +30     
- Misses                   21779    21969     +190     
+ Partials                   275      270       -5     

Impacted Files	Coverage Δ
app/grants/urls.py	100.00% <ø> (ø)
app/grants/models.py	43.09% <5.00%> (-2.44%)	⬇️
app/grants/views.py	15.46% <15.78%> (+0.09%)	⬆️
app/economy/tx.py	17.82% <50.00%> (ø)
app/retail/emails.py	20.95% <0.00%> (-0.12%)	⬇️
app/grants/clr.py	0.00% <0.00%> (ø)
app/quests/views.py	16.22% <0.00%> (ø)
...rketing/management/commands/no_applicants_email.py	0.00% <0.00%> (ø)
...eting/management/commands/assemble_leaderboards.py	39.73% <0.00%> (ø)
app/grants/management/commands/analytics_clr.py	0.00% <0.00%> (ø)
... and 8 more

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[mds1]

Hey @thelostone-mc and @apbendi, this PR has most of the core functionality already, so I think it would be good to get a first round of reviews now. Current functionality that was added:

1. Main zkSync checkout flow. See the description above for instructions on how to test this
2. JSONStore is used to indicate whether a user was interrupted during zkSync checkout. Upon visiting the cart, we check this, and do not let them do another checkout until they finish the first checkout. Currently the proper modal will show up, but the "finish checkout" functionality is not yet finished
   • You can test this feature by confirming the tx in step 3 then immediately closing/refreshing the page. You should also be warned before closing the page if you've confirmed the tx in step 3
3. Transaction validator was updated to not mark contributions as complete until the zkSync transfer was done on L2. Can test similarly to above

[mds1]

@thelostone-mc New changes just pushed:

• zkSync modal can now only be closed by pressing the "X", to prevent accidental closures
• zkSync checkout can be resumed when interrupted by visiting the carts page. This should support cases were the deposit tx was dropped and replaced
• Add "Transaction Processing Info", "Grant Creation", and "Grant Details" updates of these Figma mockups

[mds1]

Additional updates. This is probably a good final set of changes for this PR:

• Batch deposit address was updated since that is now deployed on mainnet
• If the user only is checking out with 1 token, they use the regular zkSync contract instead of our batch deposit contract. This saves them about 15k gas
• Does not allow zkSync checkout with unsupported tokens

[thelostone-mc]

looks gooood

[thelostone-mc]

Any thoughts on how we'd improve this ?

[mds1]

There's two situations to consider:

1. User is only checking out with one token, e.g. only DAI
2. User is checking out with 2 or more tokens, e.g. DAI and ETH

For case 1, zkSync checkout only supports [ 'ETH', 'DAI', 'USDC', 'USDT', 'LINK', 'WBTC', 'PAN' ], so we can find mainnet deposits using those tokens (or just make some ourselves if we can't find any) and use those for the estimates.

For case 2, it gets a little tricker. Ganache fork of mainnet seemed to be returning wrong gas estimates when I tested earlier. If I can figure out why and how to make those more accurate, that is the easiest approach, and we can just test every combination and go from there. If that approach won't work, I need to think about this more and am open to ideas! 🙂

[owocki]

+1 for improving the gas limits pls. its very scary to see a 1mm gas estimate as an end user