Merge pull request #1 from trishume/dlang

Dlang

.gitignore

@@ -1,6 +1,8 @@
-.tern-port
-server
-nimcache
 data
-lib/graph
-jester
+.dub
+docs.json
+__dummy.html
+*.o
+*.obj
+ratewithscience
+__test__library__

Readme.md

@@ -4,7 +4,7 @@ A web app for finding a rating scale between two arbitrary things.
 Ever wanted to rate something on a scale of David Hasselhoff to the Eiffel Tower? Well now you can.
 
 [Dave Pagurek](http://davepagurek.com/) and I made this for the [TerribleHack Winter 2015](http://terriblehack.website/) hackathon. I wrote the backend, Dave wrote the frontend.
-I later rewrote the backend in [Nim](http://nim-lang.org/) to make it cleaner and easier to deploy.
+I later rewrote the backend in [Nim](http://nim-lang.org/) and then [D](http://dlang.org) to make it cleaner and easier to deploy as well as learn new languages.
 
 Try it out at [http://ratewith.science](http://ratewith.science)!
 
@@ -21,16 +21,24 @@ Dave's JS sends my backend two endpoints via AJAX and my backend gives back a li
 ## The Current Tech
 
 The frontend is written in static HTML and JS with CSS3 animations and properties for extra fancy design.
-The backend was recently rewritten in [Nim](http://nim-lang.org/) by Tristan as a way of learning the language and make the whole thing less hacky than the old Rust version was.
+The backend is currently written in [D](http://dlang.org/), which is the third compiled language I (Tristan) have written the same thing in.
+Now I have a nice comparison corpus of having implemented the exact same app in Rust, Nim and D. It is a great way to try out a language.
 
-The Nim backend uses the [Jester][] web framework to serve Dave's frontend as well
-as respond to API calls for path finding.
+The D backend uses the [Vibe.d][] web framework to serve Dave's frontend as well
+as respond to API calls for path finding. It was a mostly straightforward translation of the Nim version, but a bit nicer.
 
 First the backend translates the given pages into something usable with the binary graph using the [wikicrush][] `xindex.db` file with Nim's standard Sqlite library.
 The backend then performs a breadth-first-search on an in-memory buffer of the [wikicrush][] `indexbi.bin` file.
 It first tries to BFS through only bidirectional links as these lead to better paths but if that fails it tries a single-direction search.
 Then it uses the Sqlite database to translate the path offsets it got back into article names and ships them back to the frontend as JSON.
 
+The JSON API is generated using [Vibe.d's fancy REST generator][https://vibed.org/api/vibe.web.rest/].
+
+## The Nim Tech
+
+The first rewrite was done in [Nim](http://nim-lang.org/) by Tristan as a way of learning the language and make the whole thing less hacky than the old Rust version was.
+The Nim backend used the [Jester][] web framework to serve Dave's frontend as well as respond to API calls for path finding.
+
 ## The Original Tech (From the Hackathon)
 The backend uses a compiled Rust binary from the [ratews_backend](https://github.com/trishume/ratews_backend) project to find a path.
 
@@ -55,3 +63,5 @@ Steps:
 
 [wikicrush]: https://github.com/trishume/wikicrush
 [Jester]: https://github.com/dom96/jester
+[Vibe.d]: https://vibed.org/
+[d2sqlite3]: https://github.com/biozic/d2sqlite3

dub.json

@@ -0,0 +1,15 @@
+{
+  "name": "ratewithscience",
+  "description": "The backend for http://ratewith.science/",
+  "copyright": "Copyright © 2016, Tristan Hume",
+  "authors": ["Tristan Hume"],
+  "libs": ["sqlite3"],
+  "lflags": ["-L/usr/local/Cellar/sqlite/3.8.10.2/lib/"],
+  "dependencies": {
+    "d2sqlite3": "~>0.9.0",
+    "dunit": "~>1.0.10",
+    "gfm:core": "~>3.0.11",
+    "vibe-d": "~>0.7.26"
+  },
+  "versions": ["VibeDefaultMain"]
+}

dub.selections.json

@@ -0,0 +1,14 @@
+{
+	"fileVersion": 1,
+	"versions": {
+		"libevent": "2.0.1+2.0.16",
+		"libev": "5.0.0+4.04",
+		"openssl": "1.1.4+1.0.1g",
+		"memutils": "0.4.4",
+		"vibe-d": "0.7.26",
+		"d2sqlite3": "0.9.0",
+		"gfm": "3.0.11",
+		"libasync": "0.7.5",
+		"dunit": "1.0.12"
+	}
+}

public/index.html

@@ -52,7 +52,7 @@ <h2>Rate things on arbitrary scales with scientific accuracy</h2>
         <section id="error" class="hidden">
             <div class="wrapper">
                 <h2>Uh oh!</h2>
-                <p>We couldn't make a scale with your input. Try some other endpoints!</p>
+                <p id="errormsg">We couldn't make a scale with your input. Try some other endpoints!</p>
                 <input type="button" id="close_error" value="Try again">
             </div>
         </section>

public/rws.js

@@ -109,23 +109,31 @@ document.getElementById("go").addEventListener("click", function() {
             },
             dataType: "json",
             success: function(result) {
-                if (result.status == "ok") {
+                if (result.status > 2) { // success
                     var scale = document.getElementById("scale");
                     scale.classList.remove("quality");
-                    if (result.quality && result.quality == 2) {
+                    if (result.status == 3) {
                         scale.classList.add("quality");
                     }
                     scale.innerHTML = "";
-                    for (var i=0; i<result.scale.length; i++) {
+                    for (var i=0; i<result.path.length; i++) {
                         var item = "<div class='item'><h3>" + (i+1) + "</h3>"
-                        item += "<a href='http://en.wikipedia.org/wiki/" + encodeURIComponent(result.scale[i]) + "' target='_blanl'>" + result.scale[i] + "</a>"
+                        item += "<a href='http://en.wikipedia.org/wiki/" + encodeURIComponent(result.path[i]) + "' target='_blanl'>" + result.path[i] + "</a>"
                         item += "<div class='bg'></div>";
                         item += "</div>";
                         scale.innerHTML += item;
                     }
                     hide(document.getElementById("loading"));
                     show(document.getElementById("results"));
                 } else {
+                    var errorMsgEl = document.getElementById("errormsg");
+                    if(result.status == 0) {
+                        errorMsgEl.innerHTML = "There's no path between these pages! This is super rare, you must be good at finding obscure pages.";
+                    } else if(result.status == 1) {
+                        errorMsgEl.innerHTML = "I can't find a Wikipedia page for your start point. This might be because I can't currently use redirects as endpoints.";
+                    } else if(result.status == 2) {
+                        errorMsgEl.innerHTML = "I can't find a Wikipedia page for your end point. This might be because I can't currently use redirects as endpoints.";
+                    }
                     hide(document.getElementById("loading"));
                     show(document.getElementById("error"));
                 }

source/app.d

@@ -0,0 +1,39 @@
+import std.stdio, std.datetime;
+import vibe.d;
+import graph;
+
+Graph wikiGraph;
+TaskMutex mtx;
+
+@path("/api")
+interface Api {
+  @path("findscale")
+  graph.Path getFindScale(string start, string stop);
+}
+
+class ApiImpl : Api {
+  override:
+  graph.Path getFindScale(string start, string stop) {
+    StopWatch sw = StopWatch(AutoStart.yes);
+    writeln("Pathing from ", start, " to ", stop);
+    mtx.lock();
+    auto res = wikiGraph.rateWithScience(start, stop);
+    mtx.unlock();
+    sw.stop();
+    writeln("Done pathing with result", res, " it took ", sw.peek().msecs, "ms");
+    return res;
+  }
+}
+
+shared static this() {
+  wikiGraph = new Graph("data");
+  mtx = new TaskMutex;
+
+  auto router = new URLRouter;
+  router.registerRestInterface(new ApiImpl());
+  router.get("*", serveStaticFiles("./public/"));
+
+  auto settings = new HTTPServerSettings;
+  settings.port = 5000;
+  listenHTTP(settings, router);
+}