Directly use resource server URL to generate URLs for Open Payments resources

[mkurapov]

Context

Currently, in order to generate the URLs for Open Payments resources (like incoming payments, quotes, outgoing payments), we generate the URL as such:

  public getUrl(walletAddress: WalletAddress): string {
    const url = new URL(walletAddress.url)
    return `${url.origin}${Quote.urlPath}/${this.id}`
  }

However, this assumes that the wallet address URL origin is equal to the resource server. In a typical implementation, wallet address URL origin = resource server URL, but in the context of Open Payments, it doesn't need to be.

To allow for more flexibility, instead of using wallet address URL origin to getUrl on a resouce, we should use the Open Payments resource server URL directly.

Todos

• Update the getUrl methods on our models to directly use the resource server URL instead of the wallet address URL origin