feat() add host matching support to controllers

[nonplus]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Other... Please describe:

What is the current behavior?

Currently the request hostname is not taken into consideration when dispatching routes.

Issue Number: #2521

What is the new behavior?

• New optional host @Controller setting that changes controller to only route if the request host matches.
• The host value may capture parameters, e.g. :tenant.example.com
• New @HostParam parameter decorator that returns captured host parameter, e.g. @HostParam('tenant') tenant: string
• Caveat: Due to how Fastify implements routing, this feature only works in the default (Express) router. When used with Fastify, routing to a controller with a{ host: ":tenant.example.com" } filter will return a 500 response with an HTTP Adapter does not support filtering on { host: ":tenant.example.com" } message.

@Controller({ host: ':tenant.example.com')
export class TenantController {
  @Get()
  public getInfo(@HostParam('tenant') tenant: string) {
    return `Tenant from hostname: [${tenant}]`;
  }
}

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[coveralls]

Pull Request Test Coverage Report for Build 3336

• 26 of 35 (74.29%) changed or added relevant lines in 9 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.05%) to 95.235%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
packages/core/router/router-explorer.ts	11	20	55.0%

Totals
Change from base Build 2285:	-0.05%
Covered Lines:	4137
Relevant Lines:	4344

---

💛 - Coveralls

[kamilmysliwiec]

Thanks for your contribution! I'll review it shortly.

[kamilmysliwiec]

Can't we just return handler here? (without setting the hosts property on req)

[kamilmysliwiec]

Would you like to create a PR to the docs with this feature? :)

[nonplus]

@kamilmysliwiec, the docs are done via the docs.nestjs.com repo, right? I'll open a PR today.

[nonplus]

PR for documentation update: nestjs/docs.nestjs.com#737

[kamilmysliwiec]

Thank you! This will be published as 6.12.0

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.