Merge pull request #39 from sparsetech/issue/37

Route: Require exact match when parsing

manual/introduction.md

@@ -1,5 +1,5 @@
 # Introduction
-Trail is a routing library for Scala. It allows to define type-safe routes, generate URLs and perform pattern matching.
+Trail is a routing library for Scala. It allows defining type-safe routes, generating URLs and performing pattern matching.
 
 ## Installation
 Add the following dependencies to your build configuration:
@@ -10,35 +10,46 @@ libraryDependencies += "tech.sparse" %%% "trail" % "%version%"  // Scala.js, Sca
 ```
 
 ## Usage
-Create a route:
+First, import Trail's DSL and define a type-safe route:
 <listing id="route">
 
-Create a string URL by filling the placeholders of the route:
+To fill the route's placeholders, call the `url()` or `apply()` functions:
 <listing id="url">
 
-Parse an URL:
-<listing id="map">
+When parsing an URL, Trail maps the values onto Scala types. The result will also contain any unmatched path elements, arguments or the fragment:
+<listing id="parse">
 
-Define and parse a route with a query parameter:
+We will now define a route with one query parameter. Here, we are only interested in the arguments and exact path matches. For this use case, Trail provides the function `parseArgs()`:
 <listing id="query-params">
 
-A query parameter may be optional:
+The output shows that additional arguments are still permitted. If this is undesired, you can call `parseArgsStrict()` to parse a route more strictly:
+<listing id="query-params-strict">
+
+Routes may specify optional query parameters:
 <listing id="query-params-opt">
 
-A fragment can be specified:
+You can match fragments, too:
 <listing id="query-fragment">
 
-Create a routing table:
-<listing id="parse">
+Since `parseArgs()` disallows additional path elements, you can match them only on specific routes using `Elems`. It should be the last DSL combinator in the route definition:
+<listing id="additional-elems">
+
+Similarly, additional parameters can be matched with `Params`:
+<listing id="additional-params">
+
+Routing tables can be expressed with pattern matching:
+<listing id="routing-table">
+
+The underlying `unapply()` function calls `parseArgs()` instead of `parse()`. Therefore, the ordering of routes does not impact precedence.
 
-Note that you can populate the `trail.Path()` data structure yourself and use it in place of its string counterpart. This is useful if you are using a third-party routing library which already provides you with a deconstructed URL:
+You may populate the `trail.Path()` data structure yourself and use it in place of an URL. This is useful if an HTTP server already provides the path and arguments of requests:
 <listing id="parse-path">
 
-Define a custom codec that can be used in arguments, parameters and fragments:
+Trail defines codecs for common Scala types. You can define a custom codec for any type. These codecs can be used in arguments, parameters and fragments:
 <listing id="custom-codec">
 
-Define a custom path element type:
+It is possible to define a custom path element type, too:
 <listing id="custom-path-elem">
 
-Encode and decode [URI values](https://en.wikipedia.org/wiki/Percent-encoding):
+Trail provides helper utilities, for example to encode and decode [URI values](https://en.wikipedia.org/wiki/Percent-encoding):
 <listing id="uri-values">

manual/listings.json

@@ -4,40 +4,55 @@
     "language" : "scala",
     "result" : "%C3%A4%C3%B6%C3%BC\näöü"
   },
-  "map" : {
-    "code" : "println(details.parse(\"/details/42\"))",
+  "url" : {
+    "code" : "println(details.url(1))\nprintln(details(1))",
     "language" : "scala",
-    "result" : "Some(42)"
+    "result" : "/details/1\n/details/1"
   },
-  "url" : {
-    "code" : "println(details.url(1))  // Shorter: details(1)",
+  "query-params-strict" : {
+    "code" : "println(route.parseArgsStrict(\"/details/sub-page\"))\nprintln(route.parseArgsStrict(\"/details?show=false\"))\nprintln(route.parseArgsStrict(\"/details?show=false&a=b\"))\nprintln(route.parseArgsStrict(\"/details#frag\"))",
     "language" : "scala",
-    "result" : "/details/1"
+    "result" : "None\nSome(false)\nNone\nNone"
   },
   "parse-path" : {
-    "code" : "val result2 = trail.Path(\"/user/hello\", List(\"show\" -> \"false\")) match {\n  case details (a)      => s\"details: $a\"\n  case userInfo((u, s)) => s\"user: $u, show: $s\"\n}\nprintln(result2)",
+    "code" : "val (requestPath, requestParams) = (\"/user/hello\", List(\"show\" -> \"false\"))\nval result2 = trail.Path(requestPath, requestParams) match {\n  case details (a)      => s\"details: $a\"\n  case userInfo((u, s)) => s\"user: $u, show: $s\"\n}\nprintln(result2)",
     "language" : "scala",
     "result" : "user: hello, show: false"
   },
+  "additional-elems" : {
+    "code" : "val routeAdditionalElems = Root / \"a\" / Elems\nprintln(routeAdditionalElems.parseArgs(\"/a/b/c\"))",
+    "language" : "scala",
+    "result" : "Some(List(b, c))"
+  },
   "query-params-opt" : {
-    "code" : "val routeParamsOpt = Root / \"details\" & Param[Int](\"id\") & Param[Option[Boolean]](\"show\")\nprintln(routeParamsOpt.parse(\"/details?id=42\"))",
+    "code" : "val routeParamsOpt = Root / \"details\" & Param[Int](\"id\") & Param[Option[Boolean]](\"show\")\nprintln(routeParamsOpt.parseArgs(\"/details?id=42\"))",
     "language" : "scala",
     "result" : "Some((42,None))"
   },
   "parse" : {
+    "code" : "println(details.parse(\"/details/42\"))\nprintln(details.parse(\"/details/42/sub-page?name=value\"))\nprintln(details.parse(\"/details/42/sub-page?name=value#frag\"))",
+    "language" : "scala",
+    "result" : "Some((42,Path(,List(),None)))\nSome((42,Path(sub-page,List((name,value)),None)))\nSome((42,Path(sub-page,List((name,value)),Some(frag))))"
+  },
+  "query-params" : {
+    "code" : "val route = Root / \"details\" & Param[Boolean](\"show\")\nprintln(route.parseArgs(\"/details/sub-page\"))\nprintln(route.parseArgs(\"/details?show=false\"))\nprintln(route.parseArgs(\"/details?show=false&a=b\"))\nprintln(route.parseArgs(\"/details#frag\"))",
+    "language" : "scala",
+    "result" : "None\nSome(false)\nSome(false)\nNone"
+  },
+  "routing-table" : {
     "code" : "val userInfo = Root / \"user\" / Arg[String] & Param[Boolean](\"show\")\n\nval result = \"/user/hello?show=false\" match {\n  case details (a)      => s\"details: $a\"\n  case userInfo((u, s)) => s\"user: $u, show: $s\"\n}\nprintln(result)",
     "language" : "scala",
     "result" : "user: hello, show: false"
   },
-  "query-params" : {
-    "code" : "val route = Root / \"details\" & Param[Boolean](\"show\")\nprintln(route.parse(\"/details?show=false\"))",
+  "additional-params" : {
+    "code" : "val routeAdditionalParams = Root / Arg[String] & Params\nprintln(routeAdditionalParams.parseArgs(\"/a?param1=value1&param2=value2\"))",
     "language" : "scala",
-    "result" : "Some(false)"
+    "result" : "Some((a,List((param1,value1), (param2,value2))))"
   },
   "route" : {
-    "code" : "import trail._\nimport shapeless._\n\nval details = Root / \"details\" / Arg[Int]\nprintln(details)",
+    "code" : "import trail._\nval details = Root / \"details\" / Arg[Int]",
     "language" : "scala",
-    "result" : "ConcatRight(ConcatRight(Root,Static(details)),Dynamic(Arg()))"
+    "result" : null
   },
   "custom-path-elem" : {
     "code" : "case class Foo(bar: String)\nimplicit object FooElement extends StaticElement[Foo](_.bar)\n\nprintln((Root / Foo(\"asdf\")).url(()))",
@@ -50,7 +65,7 @@
     "result" : "/export/1,2,3"
   },
   "query-fragment" : {
-    "code" : "val routeFragment = Root $ Fragment[Int]\nprintln(routeFragment.parse(\"/#42\"))",
+    "code" : "val routeFragment = Root $ Fragment[Int]\nprintln(routeFragment.parseArgs(\"/#42\"))",
     "language" : "scala",
     "result" : "Some(42)"
   }

manual/src/main/scala/trail/manual/Listings.scala

@@ -7,30 +7,47 @@ object Listings extends App {
 
   listing("route")
   import trail._
-  import shapeless._
-
   val details = Root / "details" / Arg[Int]
-  println(details)
 
   listing("url")
-  println(details.url(1))  // Shorter: details(1)
+  println(details.url(1))
+  println(details(1))
 
-  listing("map")
+  listing("parse")
   println(details.parse("/details/42"))
+  println(details.parse("/details/42/sub-page?name=value"))
+  println(details.parse("/details/42/sub-page?name=value#frag"))
 
   listing("query-params")
   val route = Root / "details" & Param[Boolean]("show")
-  println(route.parse("/details?show=false"))
+  println(route.parseArgs("/details/sub-page"))
+  println(route.parseArgs("/details?show=false"))
+  println(route.parseArgs("/details?show=false&a=b"))
+  println(route.parseArgs("/details#frag"))
+
+  listing("query-params-strict")
+  println(route.parseArgsStrict("/details/sub-page"))
+  println(route.parseArgsStrict("/details?show=false"))
+  println(route.parseArgsStrict("/details?show=false&a=b"))
+  println(route.parseArgsStrict("/details#frag"))
 
   listing("query-params-opt")
   val routeParamsOpt = Root / "details" & Param[Int]("id") & Param[Option[Boolean]]("show")
-  println(routeParamsOpt.parse("/details?id=42"))
+  println(routeParamsOpt.parseArgs("/details?id=42"))
 
   listing("query-fragment")
   val routeFragment = Root $ Fragment[Int]
-  println(routeFragment.parse("/#42"))
+  println(routeFragment.parseArgs("/#42"))
 
-  listing("parse")
+  listing("additional-elems")
+  val routeAdditionalElems = Root / "a" / Elems
+  println(routeAdditionalElems.parseArgs("/a/b/c"))
+
+  listing("additional-params")
+  val routeAdditionalParams = Root / Arg[String] & Params
+  println(routeAdditionalParams.parseArgs("/a?param1=value1&param2=value2"))
+
+  listing("routing-table")
   val userInfo = Root / "user" / Arg[String] & Param[Boolean]("show")
 
   val result = "/user/hello?show=false" match {
@@ -40,7 +57,8 @@ object Listings extends App {
   println(result)
 
   listing("parse-path")
-  val result2 = trail.Path("/user/hello", List("show" -> "false")) match {
+  val (requestPath, requestParams) = ("/user/hello", List("show" -> "false"))
+  val result2 = trail.Path(requestPath, requestParams) match {
     case details (a)      => s"details: $a"
     case userInfo((u, s)) => s"user: $u, show: $s"
   }

shared/src/main/scala/trail/Path.scala

@@ -64,4 +64,4 @@ object PathParser {
 
     Path(path, args, fragment)
   }
-}
+}