feat: implemented email validation in the homepage newsletter

[AKACHI-4]

Description

• Add email validation to the Subscribe Newsletter homepage.
• Use AbstractAPI Email Validation, which provides 100 API requests per month.
• Generalize the code for all three newsletter statuses: success, error, and invalid.

Related issue(s)
Fixes #2125

Implementation

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[asyncapi-bot]

⚡️ Lighthouse report for the changes in this PR:

Category	Score
🔴 Performance	34
🟢 Accessibility	98
🟢 Best practices	92
🟢 SEO	100
🔴 PWA	33

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[anshgoyalevil]

Use AbstractAPI Email Validation, which provides 100 API requests per month

IMHO, we won't use any paid external service unless it is a Freemium tool (with large FREE limits, unlike 100 requests per month, which can be abused by even a single bot).

[AKACHI-4]

Use AbstractAPI Email Validation, which provides 100 API requests per month

IMHO, we won't use any paid external service unless it is a Freemium tool (with large FREE limits, unlike 100 requests per month, which can be abused by even a single bot).

Ah okay. Got it. I will switch to some other tool that's free with a high limit.

Also, I'm open to any member suggesting some tools.

[RegretfulWinter]

Hi @AKACHI-4 , I did some research on Email verification tool and I found some tools (for free) :

• check if email exists. . Did not speficy the number of verification request limit of validation. Its SaaS version is paid but for this open source version it's free.
• verifalia. Stated that they doesnt have a verification limit, but having HTTP rate limits.

Hope it helps. Will update if I found more tools

[AKACHI-4]

Hey @RegretfulWinter, Thanks for this .. It means a lot to me. I will check out and commit changes ASAP.

[AKACHI-4]

I am considering using @chimanos/deep-email-validator. After reviewing the code and documentation, I found that this package consolidates regex, SMTP, and disposable mail checks. The package is free and can be downloaded from npm.

The reasons I chose not to go with the following options are:

• check-if-mail-exists: While the Docker method seems viable, the problem is that we would have to keep a server running regardless of the current status of newsletter requests. This could result in extra processing as we would have to deploy it on a cloud for users to maintain.
• verifalia : The API documentation is somewhat tangled and it's hard to obtain any fixed information regarding the API's use with the current request rate limit. It also throws an HTTP 429 Status Code when the limit is exceeded.

However, I am open to further suggestions for improvement.

[AKACHI-4]

Now, that's not good. I should have checked before making a decision... Results, I should continue my search and work on this issue.

[AKACHI-4]

With my search so far, it seems impossible to find a completely free email validation service. The best I've found offers 50 validations per day, which could easily be exhausted by bot spamming.

What could be the solution?
Perhaps using npm packages or creating something myself. For instance, I could use Rust code and check-if-mail-exists, then deploy it. However, I must consider the worst-case scenario of handling 1 million validation requests per day. That's a significant load, and even my API might not be able to handle it without asking me to pay.

I suppose 50 validations per day might be sufficient. If not, I could use regex and SMTP check npm packages as an alternative.

[AKACHI-4]

• verifalia. Stated that they doesnt have a verification limit, but having HTTP rate limits.

The part where they say unlimited is supposed to refer to concurrent verification jobs at a time, and they don't have a limit over that, which in no way corresponds with the count of requests a single account or user can make.

I logged in and found only those 50 daily credits tho.

[sambhavgupta0705]

@AKACHI-4 what's the status of this PR

[sambhavgupta0705]

closing this as there is no update from the contributor