From 1923f2d08e2342998e192037d476c12f8b921d3c Mon Sep 17 00:00:00 2001
From: Tommi Reiman <tommi@iki.fi>
Date: Thu, 14 Jun 2018 17:52:57 +0300
Subject: [PATCH] handle query-parameters in reverse routing

---
 CHANGELOG.md                             | 16 ++++++++++++++++
 modules/reitit-core/src/reitit/core.cljc |  6 ++++++
 modules/reitit-core/src/reitit/impl.cljc |  7 +++++++
 test/cljc/reitit/core_test.cljc          | 11 +++++++++++
 test/cljc/reitit/impl_test.cljc          | 16 ++++++++++++++++
 5 files changed, 56 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7f223f96..5aa591cd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -21,6 +21,22 @@
 ;  :query {:int 10}}
 ```
 
+* `reitit.core/match->path` to create full paths from match, including the query parameters:
+
+```clj
+(require '[reitit.core :as r])
+
+(-> (r/router ["/:a/:b" ::route])
+    (r/match-by-name! ::route {:a "olipa", :b "kerran"})
+    (r/match->path))
+; "/olipa/kerran"
+
+(-> (r/router ["/:a/:b" ::route])
+    (r/match-by-name! ::route {:a "olipa", :b "kerran"})
+    (r/match->path {:iso "pöriläinen"}))
+; "/olipa/kerran?iso=p%C3%B6ril%C3%A4inen"
+```
+
 ## 0.1.2 (2018-6-6)
 
 ### `reitit-core`
diff --git a/modules/reitit-core/src/reitit/core.cljc b/modules/reitit-core/src/reitit/core.cljc
index b3785447..2a22f1a7 100644
--- a/modules/reitit-core/src/reitit/core.cljc
+++ b/modules/reitit-core/src/reitit/core.cljc
@@ -129,6 +129,12 @@
        (impl/throw-on-missing-path-params
          (:template match) (:required match) path-params)))))
 
+(defn match->path
+  ([match]
+   (match->path match nil))
+  ([match query-params]
+   (some-> match :path (cond-> query-params (str "?" (impl/query-string query-params))))))
+
 (def default-router-options
   {:lookup name-lookup
    :expand expand
diff --git a/modules/reitit-core/src/reitit/impl.cljc b/modules/reitit-core/src/reitit/impl.cljc
index 49409265..003f2870 100644
--- a/modules/reitit-core/src/reitit/impl.cljc
+++ b/modules/reitit-core/src/reitit/impl.cljc
@@ -209,3 +209,10 @@
       (assoc m k (url-encode (into-string v))))
     {}
     params))
+
+(defn query-string
+  "shallow transform of query parameters into query string"
+  [params]
+  (->> params
+       (map (fn [[k v]] (str (url-encode (into-string k)) "=" (url-encode (into-string v)))))
+       (str/join "&")))
diff --git a/test/cljc/reitit/core_test.cljc b/test/cljc/reitit/core_test.cljc
index f8233888..f1a27584 100644
--- a/test/cljc/reitit/core_test.cljc
+++ b/test/cljc/reitit/core_test.cljc
@@ -246,3 +246,14 @@
               [["/a"] ["/a"]]))))
     (testing "can be configured to ignore"
       (is (not (nil? (r/router [["/a"] ["/a"]] {:conflicts (constantly nil)})))))))
+
+(deftest match->path-test
+  (let [router (r/router ["/:a/:b" ::route])]
+    (is (= "/olipa/kerran"
+           (-> router
+               (r/match-by-name! ::route {:a "olipa", :b "kerran"})
+               (r/match->path))))
+    (is (= "/olipa/kerran?iso=p%C3%B6ril%C3%A4inen"
+           (-> router
+               (r/match-by-name! ::route {:a "olipa", :b "kerran"})
+               (r/match->path {:iso "pöriläinen"}))))))
diff --git a/test/cljc/reitit/impl_test.cljc b/test/cljc/reitit/impl_test.cljc
index 1f669b83..1d437ed8 100644
--- a/test/cljc/reitit/impl_test.cljc
+++ b/test/cljc/reitit/impl_test.cljc
@@ -48,3 +48,19 @@
                             :k :kikka
                             :qk ::kikka
                             :nil nil}))))
+
+(deftest query-params-test
+  (are [x y]
+    (= (impl/query-string x) y)
+    {:a "b"} "a=b"
+    {"a" "b"} "a=b"
+    {:a 1} "a=1"
+    {:a nil} "a="
+    {:a :b :c "d"} "a=b&c=d"
+    {:a "b c"} "a=b%20c"))
+
+; TODO: support seq values?
+;{:a ["b" "c"]} "a=b&a=c"
+;{:a ["c" "b"]} "a=c&a=b"
+;{:a (seq [1 2])} "a=1&a=2"
+;{:a #{"c" "b"}} "a=b&a=c"