docs: Update README

README.md

@@ -38,7 +38,8 @@ an ACME account), `--acme-file` (`ACME_FILE`; Path to the file where ACME accoun
 are stored in) are additionally required. `--acme-server` (`ACME_SERVER`) should also
 be set to your ACME CA's directory URL as this option defaults to the
 [Let's Encrypt Staging Environment](https://letsencrypt.org/docs/staging-environment/). Note that using this optional implies that you accept your
-configured ACME CA's Terms of Service.
+configured ACME CA's Terms of Service. rio will also spawn an unencrypted HTTP server that is bound to the host specified with `--http-host` (`HTTP_HOST`) and
+the port specified with `--http-port` (`HTTP_PORT`). The functionality of this second HTTP server is to upgrade plain HTTP requests to HTTPS requests.
 
 You can also run with `--debug` (`DEBUG_ENABLE=1`) to enable debug logging.
 

internal/repo/client.go

@@ -19,12 +19,18 @@ type GetRepositoryMethod func(username, repositoryName string) (Repository, erro
 // <username>/<repository>@<branch> exists. If not, returns "", error.
 type GetFileMethod func(username, repositoryName, branch, path string, since *time.Time) ([]byte, bool, error)
 
+// Returns the result of a CNAME lookup for @domain.
 type LookupCNAMEMethod func(domain string) (string, error)
 
+// Return the repository the domain should point to by looking up the TXT record
+// "_rio-pages.<domain>".
 type LookupRepoTXTMethod func(domain string) (string, error)
 
+// Check of the repository <username>/<repositoryName> contains the specified
+// branch.
 type HasBranchMethod func(username, repositoryName, branchName string) bool
 
+// Check if the specified username exists.
 type HasUserMethod func(username string) bool
 
 type Repository struct {