What is the difference between path and pathPrefix directives?

In Akka HTTP, the path and pathPrefix directives are used to match and handle parts of the request URI. While both are involved in routing based on the path, they differ in how they match and handle the URI. Here's a detailed comparison:

1. path Directive :

The path directive is used to match exact path segments in the URI. It requires the entire remaining path to match exactly, with no additional segments allowed unless explicitly defined.

Key Characteristics:

  • Matches the exact path specified.
  • Does not allow additional segments after the match.
  • Commonly used for specific, well-defined routes.

Example :

val route = path("users") {
  complete("Users endpoint")
}
?
2. pathPrefix Directive :

The pathPrefix directive is used to match the beginning (prefix) of a path. It allows additional segments in the URI after the matched prefix, which can be handled by nested routes.

Key Characteristics:

  • Matches the specified prefix and allows the remaining path to be processed by child directives or routes.
  • Ideal for grouping routes under a common base path.

Example :

val route = pathPrefix("users") {
  path("create") {
    complete("Create user")
  } ~
  path(IntNumber) { userId =>
    complete(s"Details for user $userId")
  }
}?