Add min amount validation to server side one time payments

[tjmw]

What are you doing in this PR?

Add min amount validation to the payment API for one time contributions.

Trello Card

Why are you doing this?

We already have client side validation for this, but we'd like to enforce server side too as this makes us more robust.

How to test

I've tested this in CODE. In order to do this I had to temporarily remove the client side validation. The error message we show in this case is quite generic, but I think in general we don't expect users to hit this as the client side validation should kick in before the request even makes it to the backend.

Stripe:

PayPal:

If we need to, perhaps we could follow up with a more contextual error message in another PR.

How can we measure success?

Have we considered potential risks?

Accessibility test checklist

• Tested with screen reader
• Navigable with keyboard
• Colour contrast passed
• The change doesn't use only colour to convey meaning

Screenshots

[github-actions]

Deploy build 12795 of support::stripe-patrons-data to CODE

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From guardian/actions-riff-raff.

[github-actions]

Size Change: 0 B

Total Size: 2.24 MB

ℹ️ View Unchanged

Filename	Size
./public/compiled-assets/javascripts/[countryGroupId]/events/router.js	90.1 kB
./public/compiled-assets/javascripts/[countryGroupId]/router.js	267 kB
./public/compiled-assets/javascripts/ausMomentMap.js	108 kB
./public/compiled-assets/javascripts/contributionsRedirectStyles.js	20 B
./public/compiled-assets/javascripts/digitalSubscriptionLandingPage.js	237 kB
./public/compiled-assets/javascripts/downForMaintenancePage.js	70.7 kB
./public/compiled-assets/javascripts/error404Page.js	70.7 kB
./public/compiled-assets/javascripts/error500Page.js	70.6 kB
./public/compiled-assets/javascripts/favicons.js	617 B
./public/compiled-assets/javascripts/paperSubscriptionCheckoutPage.js	175 kB
./public/compiled-assets/javascripts/paperSubscriptionLandingPage.js	87.5 kB
./public/compiled-assets/javascripts/payPalErrorPage.js	69 kB
./public/compiled-assets/javascripts/payPalErrorPageStyles.js	20 B
./public/compiled-assets/javascripts/promotionTerms.js	73.6 kB
./public/compiled-assets/javascripts/subscriptionsLandingPage.js	72.9 kB
./public/compiled-assets/javascripts/subscriptionsRedemptionPage.js	127 kB
./public/compiled-assets/javascripts/supporterPlusLandingPage.js	308 kB
./public/compiled-assets/javascripts/unsupportedBrowserStyles.js	20 B
./public/compiled-assets/javascripts/weeklySubscriptionCheckoutPage.js	172 kB
./public/compiled-assets/javascripts/weeklySubscriptionLandingPage.js	87.7 kB
./public/compiled-assets/webpack/136.js	2.17 kB
./public/compiled-assets/webpack/187.js	21.6 kB
./public/compiled-assets/webpack/344.js	2.01 kB
./public/compiled-assets/webpack/643.js	22.4 kB
./public/compiled-assets/webpack/706.js	107 kB

_{compressed-size-action}

[github-actions]

Deploy build 22059 of support:support-workers-mono to CODE

All deployment options

• Deploy build 22059 of support:support-workers-mono to CODE
• Deploy parts of build 22059 to CODE by previewing it first
• What's on CODE right now?

---

From guardian/actions-riff-raff.