something seems broken...

10 files changed, 87 insertions, 461 deletions

diff --git a/docker-compose.yml b/docker-compose.yml
index b7a8e13..dddd22a 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -4,4 +4,4 @@ services:
   manager:
     build: .
     ports:
-      - "80:80"
\ No newline at end of file
+      - 8031:80
diff --git a/main.go b/main.go
index fbf524a..4fe5ae2 100644
--- a/main.go
+++ b/main.go
@@ -1,195 +1,115 @@
 package main
 
 import (
+	"encoding/json"
 	"fmt"
-	"html/template"
+	"io/ioutil"
 	"log"
 	"net/http"
 	"net/url"
 	"strconv"
 
 	"github.com/gorilla/mux"
+
+	"git.darknebu.la/GalaxySimulator/structs"
 )
 
-type Page struct {
-	NewTree bool
-	X, Y, W float64
-}
+func indexHandler(w http.ResponseWriter, r *http.Request) {
+	infostring := `Galaxy Simulator Manager 
 
-func overviewHandler(w http.ResponseWriter, r *http.Request) {
-	t := template.Must(template.ParseFiles(
-		"tmpl/overview.html",
-		"tmpl/header.html",
-		"tmpl/nav.html",
-		"tmpl/javascript.html",
-	))
-	templateExecuteError := t.ExecuteTemplate(w, "overview", &Page{})
-	if templateExecuteError != nil {
-		log.Println(templateExecuteError)
-	}
+API: 
+	/calcallforces/{treeindex}`
+	_, _ = fmt.Fprintf(w, infostring)
 }
 
-func newtreeHandler(w http.ResponseWriter, r *http.Request) {
-	log.Println("the new tree handler was accessed")
-	// if the method used to get the page is GET, simply respond with the tree-creation form
-	if r.Method == "GET" {
-		log.Println("using a GET method")
-		t := template.Must(template.ParseFiles(
-			"tmpl/newtree.html",
-			"tmpl/header.html",
-			"tmpl/nav.html",
-			"tmpl/javascript.html",
-		))
-		templateExecuteError := t.ExecuteTemplate(w, "newtree", &Page{})
-		if templateExecuteError != nil {
-			log.Println(templateExecuteError)
-		}
-	} else {
-		log.Println("using a POST method")
-
-		// get the values from the form
-		err := r.ParseForm()
-		log.Println(err)
-		log.Println("parsed the form")
-
-		x, _ := strconv.ParseFloat(r.Form["x"][0], 64)     // x position of the midpoint of the tree
-		y, _ := strconv.ParseFloat(r.Form["y"][0], 64)     // y position of the midpoint of the tree
-		width, _ := strconv.ParseFloat(r.Form["w"][0], 64) // width the the tree
-		dbip := r.Form["db-ip"][0]                         // ip address of the database
-
-		log.Println("parsed the form arguments")
-
-		// parse the template files
-		t := template.Must(template.ParseFiles(
-			"tmpl/newtree.html",
-			"tmpl/header.html",
-			"tmpl/nav.html",
-			"tmpl/javascript.html",
-		))
-		log.Println("parsed the template file")
-
-		// execute the template
-		templateExecuteError := t.ExecuteTemplate(w, "newtree", &Page{NewTree: true, X: x, Y: y, W: width})
-
-		log.Println("executed the template")
-
-		// handle potential errors
-		if templateExecuteError != nil {
-			log.Println(templateExecuteError)
-		}
-
-		log.Println("handled potential errors")
-
-		// create the new tree by accessing the api endpoint of the database
-		postUrl := fmt.Sprintf("http://%s/new", dbip)
-
-		log.Printf("the postURL: %s", postUrl)
-		log.Println("created the url for the post request")
-
-		// define the data that should be posted
-		formData := url.Values{
-			"x": r.Form["x"],
-			"y": r.Form["y"],
-			"w": r.Form["w"],
-		}
-
-		log.Println("created the form to be sent in the post request")
-
-		// make the http Post request
-		resp, err := http.PostForm(postUrl, formData)
-
-		log.Println("sent the post request")
-
-		// some debug messages
-		log.Printf("[   ] POST response: %v", resp)
-		log.Printf("[   ] POST err: %v", err)
+func calcallforcesHandler(w http.ResponseWriter, r *http.Request) {
+	// get the tree index
+	vars := mux.Vars(r)
+	treeindex, _ := strconv.ParseInt(vars["treeindex"], 10, 0)
+
+	_, _ = fmt.Fprintf(w, "Got the treeindex, it's %d\n", treeindex)
+	fmt.Printf("treeindex: %d\n", treeindex)
+
+	// ################################################################################
+	// Calculate the center of mass and total mass of each tree
+	// ################################################################################
+
+	// db.updatestufff()
+
+	// ################################################################################
+	// Get a list of all stars in the tree
+	// ################################################################################
+	// make the following post request:
+	// db.docker.localhost/getallstars/{treeindex}
+	requesturl := fmt.Sprintf("http://db.docker.localhost/starlist/%d", treeindex)
+	_, _ = fmt.Fprintf(w, "Got the requesturl, it's %s\n", requesturl)
+	fmt.Printf("requesturl: %s\n", requesturl)
+	resp, err := http.Get(requesturl)
+	fmt.Println("After http GET, but before the error handling")
+	if err != nil {
+		fmt.Println("PANIC")
+		panic(err)
+	}
+	fmt.Println("After http GET and after error handling")
+	defer resp.Body.Close()
+
+	// read the response containing a list of all stars in json format
+	body, err := ioutil.ReadAll(resp.Body)
+	_, _ = fmt.Fprintf(w, "Got the body, it's %v\n", string(body))
+	fmt.Printf("body: %v\n", string(body))
+
+	// unmarshal the json
+	listofstars := &[]structs.Star2D{}
+	jsonUnmarschalErr := json.Unmarshal(body, listofstars)
+	if jsonUnmarschalErr != nil {
+		panic(jsonUnmarschalErr)
 	}
-}
-
-func addstarsHandler(w http.ResponseWriter, r *http.Request) {
-	// if the method used to get the page is GET, simply respond with the add-stars form
-	if r.Method == "GET" {
-		log.Println("/addstars was accessed using a GET method")
-		t := template.Must(template.ParseFiles(
-			"tmpl/addstars.html",
-			"tmpl/header.html",
-			"tmpl/nav.html",
-			"tmpl/javascript.html",
-		))
-		templateExecuteError := t.ExecuteTemplate(w, "addstars", &Page{})
-		if templateExecuteError != nil {
-			log.Println(templateExecuteError)
-		}
-	} else {
-		log.Println("/addstars was accessed using a POST method")
-
-		// get the values from the form
-		_ = r.ParseForm()
-
-		log.Println("parsed the form")
-
-		// extract some information from the form
-		dbip := r.Form["dbip"][0]                                   // ip address of the database
-		treeindex, _ := strconv.ParseInt(r.Form["tree"][0], 10, 64) // index of the tree
-		log.Println(dbip)
-		log.Println(treeindex)
-
-		log.Println("parsed the form arguments")
-
-		t := template.Must(template.ParseFiles(
-			"tmpl/addstars.html",
-			"tmpl/header.html",
-			"tmpl/nav.html",
-			"tmpl/javascript.html",
-		))
-
-		log.Println("parsed the template file")
 
-		templateExecuteError := t.ExecuteTemplate(w, "addstars", &Page{})
-		if templateExecuteError != nil {
-			log.Println(templateExecuteError)
+	fmt.Printf("listofstars: %v\n", listofstars)
+	_, _ = fmt.Fprintf(w, "Got the listofstars, it's %v\n", listofstars)
+	fmt.Printf("listofstars: %v\n", listofstars)
+
+	// ################################################################################
+	// Send the star to the simulator in order to simulate it's new position
+	// ################################################################################
+
+	// make a post request to the simulator with every star
+	for _, star := range *listofstars {
+		fmt.Printf("star: %v", star)
+		_, _ = fmt.Fprintf(w, "One of the stars is %v\n", star)
+
+		requesturlSimu := fmt.Sprintf("http://simulator.docker.localhost/calcallforces/%d", treeindex)
+
+		response, err := http.PostForm(requesturlSimu, url.Values{
+			"x":  {fmt.Sprintf("%f", star.C.X)},
+			"y":  {fmt.Sprintf("%f", star.C.Y)},
+			"vx": {fmt.Sprintf("%f", star.V.X)},
+			"vy": {fmt.Sprintf("%f", star.V.Y)},
+			"m":  {fmt.Sprintf("%f", star.M)},
+		})
+		if err != nil {
+			panic(err)
 		}
 
-		log.Println("executed the template")
-
-		// create the new tree by accessing the api endpoint of the database
-		postUrl := fmt.Sprintf("http://%s/insert/%d", dbip, treeindex)
-
-		log.Printf("the postURL: %s", postUrl)
-		log.Println("created the url for the post request")
-
-		// define the data that should be posted
-		formData := url.Values{
-			"x":  r.Form["x"],
-			"y":  r.Form["y"],
-			"vx": r.Form["vx"],
-			"vy": r.Form["vy"],
-			"m":  r.Form["mass"],
+		respBody, readAllErr := ioutil.ReadAll(response.Body)
+		if readAllErr != nil {
+			panic(readAllErr)
 		}
-
-		log.Println("created the form to be sent in the post request")
-
-		// make the http Post request
-		resp, err := http.PostForm(postUrl, formData)
-
-		log.Println("sent the post request")
-
-		// some debug messages
-		log.Printf("[   ] POST response: %v", resp)
-		log.Printf("[   ] POST err: %v", err)
+		_, _ = fmt.Fprintf(w, "%s\n", string(respBody))
 	}
+	_, _ = fmt.Fprintf(w, "DONE!\n")
+	fmt.Printf("DONE!\n")
 }
 
-func drawtreeHandler(w http.ResponseWriter, r *http.Request) {
-
+func printhiHandler(w http.ResponseWriter, r *http.Request) {
+	_, _ = fmt.Fprintf(w, "Hi there!")
 }
 
 func main() {
 	router := mux.NewRouter()
 
-	router.HandleFunc("/", overviewHandler).Methods("GET")
-	router.HandleFunc("/newtree", newtreeHandler).Methods("GET", "POST")
-	router.HandleFunc("/addstars", addstarsHandler).Methods("GET", "POST")
-	router.HandleFunc("/drawtree", drawtreeHandler).Methods("GET")
-	log.Fatal(http.ListenAndServe(":8429", router))
+	router.HandleFunc("/", indexHandler).Methods("GET")
+	router.HandleFunc("/calcallforces/{treeindex}", calcallforcesHandler).Methods("GET")
+	router.HandleFunc("/printhi", printhiHandler).Methods("GET")
+	log.Fatal(http.ListenAndServe(":8031", router))
 }
diff --git a/tmpl/addstars.html b/tmpl/addstars.html
deleted file mode 100644
index cffc31e..0000000
--- a/tmpl/addstars.html
+++ /dev/null
@@ -1,84 +0,0 @@
-{{define "addstars"}}
-    <head>
-        {{template "header"}}
-        <style>
-            .jumbotron{
-                margin: 10px;
-            }
-        </style>
-    </head>
-    <body>
-    {{template "nav"}}
-
-    <div class="container">
-        <div class="tab-content" id="nav-tabContent">
-            <div class="tab-pane fade" id="nav-overview" role="tabpanel" aria-labelledby="nav-overview-tab">There will be an overview here!</div>
-            <div class="tab-pane fade" id="nav-new-tree" role="tabpanel" aria-labelledby="nav-new-tree-tab">add tree</div>
-            <div class="tab-pane fade" id="nav-add-stars" role="tabpanel" aria-labelledby="nav-add-stars-tab">Add some stars!</div>
-            <div class="tab-pane fade" id="nav-draw-tree" role="tabpanel" aria-labelledby="nav-draw-tree-tab">Draw one of the galaxies!</div>
-        </div>
-    </div>
-
-    <div class="container">
-        <div class="jumbotron">
-            <h1 class="display-4">Add Stars</h1>
-            <p class="lead">This is the "Add your star to a tree" page! Fill out the form below for adding one of your stars into one of the trees!</p>
-            <form action="/addstars" method="post">
-
-                <hr class="my-4">
-                <div class="form-group">
-                    <input type="text" class="form-control" id="dbip" placeholder="db-ip" name="dbip">
-                </div>
-                <div class="form-group">
-                    <input type="text" class="form-control" id="tree" placeholder="tree index" name="tree">
-                </div>
-                <hr class="my-4">
-
-                <div class="form-group">
-                    <input type="text" class="form-control" id="x" placeholder="x" name="x">
-                </div>
-                <div class="form-group">
-                    <input type="text" class="form-control" id="y" placeholder="y" name="y">
-                </div>
-                <div class="form-group">
-                    <input type="text" class="form-control" id="vx" placeholder="vx" name="vx">
-                </div>
-                <div class="form-group">
-                    <input type="text" class="form-control" id="vy" placeholder="vy" name="vy">
-                </div>
-                <div class="form-group">
-                    <input type="text" class="form-control" id="m" placeholder="mass" name="mass">
-                </div>
-                <button type="submit" class="btn btn-primary">Submit</button>
-            </form>
-        </div>
-    </div>
-
-    <div class="container">
-        <div class="jumbotron">
-            <p class="lead">Optionally: select a .csv:</p>
-            <div class="input-group">
-                <div class="input-group-prepend">
-                    <span class="input-group-text" id="inputGroupFileAddon01">Upload</span>
-                </div>
-                <div class="custom-file">
-                    <input type="file" class="custom-file-input" id="inputGroupFile01" aria-describedby="inputGroupFileAddon01">
-                    <label class="custom-file-label" for="inputGroupFile01">Choose file</label>
-                </div>
-            </div>
-        </div>
-    </div>
-
-    <div class="container">
-        <div class="jumbotron">
-            <form enctype="multipart/form-data" action="http://127.0.0.1:9090/upload" method="post">
-                <input type="file" name="uploadfile" />
-                <input type="hidden" name="token" value="{{.}}"/>
-                <input type="submit" value="upload" />
-            </form>
-        </div>
-    </div>
-
-    {{template "javascript"}}
-    </body>
-{{end}}
diff --git a/tmpl/header.html b/tmpl/header.html
deleted file mode 100644
index 57e749e..0000000
--- a/tmpl/header.html
+++ /dev/null
@@ -1,11 +0,0 @@
-{{define "header"}}
-    <meta charset="utf-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
-    <title>emile.space</title>
-    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
-    <style>
-        .nav {
-            margin: 10px;
-        }
-    </style>
-{{end}}
diff --git a/tmpl/index.html b/tmpl/index.html
deleted file mode 100644
index 1f22908..0000000
--- a/tmpl/index.html
+++ /dev/null
@@ -1,24 +0,0 @@
-{{define "index"}}
-    <head>
-        {{template "header"}}
-        <style>
-            .jumbotron{
-                margin: 10px;
-            }
-        </style>
-    </head>
-    <body>
-    {{template "nav"}}
-
-    <div class="container">
-        <div class="tab-content" id="nav-tabContent">
-            <div class="tab-pane fade" id="nav-overview" role="tabpanel" aria-labelledby="nav-overview-tab">There will be an overview here!</div>
-            <div class="tab-pane fade" id="nav-new-tree" role="tabpanel" aria-labelledby="nav-new-tree-tab">add tree</div>
-            <div class="tab-pane fade" id="nav-add-stars" role="tabpanel" aria-labelledby="nav-add-stars-tab">Add some stars!</div>
-            <div class="tab-pane fade" id="nav-draw-tree" role="tabpanel" aria-labelledby="nav-draw-tree-tab">Draw one of the galaxies!</div>
-        </div>
-    </div>
-
-    {{template "javascript"}}
-    </body>
-{{end}}
diff --git a/tmpl/javascript.html b/tmpl/javascript.html
deleted file mode 100644
index 54b2810..0000000
--- a/tmpl/javascript.html
+++ /dev/null
@@ -1,5 +0,0 @@
-{{define "javascript"}}
-<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
-<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
-<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>
-{{end}}
diff --git a/tmpl/nav.html b/tmpl/nav.html
deleted file mode 100644
index 9c7a94b..0000000
--- a/tmpl/nav.html
+++ /dev/null
@@ -1,20 +0,0 @@
-{{define "nav"}}
-<div class="container">
-    <nav>
-        <ul class="nav nav-tabs">
-            <li class="nav-item">
-                <a class="nav-link" href="/">Overview</a>
-            </li>
-            <li class="nav-item">
-                <a class="nav-link" href="/newtree">New Tree</a>
-            </li>
-            <li class="nav-item">
-                <a class="nav-link" href="/addstars">Add Stars</a>
-            </li>
-            <li class="nav-item">
-                <a class="nav-link" href="/drawtree">Draw Tree</a>
-            </li>
-        </ul>
-    </nav>
-</div>
-{{end}}
diff --git a/tmpl/newtree.html b/tmpl/newtree.html
deleted file mode 100644
index 974e45c..0000000
--- a/tmpl/newtree.html
+++ /dev/null
@@ -1,60 +0,0 @@
-{{define "newtree"}}
-    <head>
-        {{template "header"}}
-        <style>
-            .jumbotron{
-                margin: 10px;
-            }
-        </style>
-    </head>
-    <body>
-    {{template "nav"}}
-
-    <div class="container">
-        <div class="tab-content" id="nav-tabContent">
-            <div class="tab-pane fade" id="nav-overview" role="tabpanel" aria-labelledby="nav-overview-tab">There will be an overview here!</div>
-            <div class="tab-pane fade" id="nav-new-tree" role="tabpanel" aria-labelledby="nav-new-tree-tab">add tree</div>
-            <div class="tab-pane fade" id="nav-add-stars" role="tabpanel" aria-labelledby="nav-add-stars-tab">Add some stars!</div>
-            <div class="tab-pane fade" id="nav-draw-tree" role="tabpanel" aria-labelledby="nav-draw-tree-tab">Draw one of the galaxies!</div>
-        </div>
-    </div>
-
-    <div class="container">
-        <div class="jumbotron">
-            <h1 class="display-4">New Tree</h1>
-            <p class="lead">This is the "Create your own tree" page! Fill out the form below to create a new (quad)tree storing a complete galaxy!</p>
-            <hr class="my-4">
-            <form action="/newtree" method="post">
-                <div class="form-group">
-                    <label for="db-ip">The ip of the database</label>
-                    <input type="text" class="form-control" id="x-pos" placeholder="db-ip" name="db-ip">
-                </div>
-                <div class="form-group">
-                    <label for="x-pos">(Center) X Position</label>
-                    <input type="text" class="form-control" id="x-pos" placeholder="x-pos" name="x">
-                </div>
-                <div class="form-group">
-                    <label for="y-pos">(Center) Y Position</label>
-
-                    <input type="text" class="form-control" id="y-pos" placeholder="y-pos" name="y">
-                </div>
-                <div class="form-group">
-                    <label for="width">Width</label>
-                    <input type="text" class="form-control" id="width" placeholder="width" name="w">
-                </div>
-                <button type="submit" class="btn btn-primary">Submit</button>
-            </form>
-        </div>
-        {{if .NewTree}}
-            <div class="alert alert-success alert-dismissible fade show" role="success">
-                <strong>Successfully created the tree!</strong> (x:{{.X}}, y:{{.Y}}), width: {{.W}}
-                <button type="button" class="close" data-dismiss="alert" aria-label="Close">
-                    <span aria-hidden="true">&times;</span>
-                </button>
-            </div>
-        {{end}}
-    </div>
-
-    {{template "javascript"}}
-    </body>
-{{end}}
diff --git a/tmpl/overview.html b/tmpl/overview.html
deleted file mode 100644
index 7f20c2c..0000000
--- a/tmpl/overview.html
+++ /dev/null
@@ -1,49 +0,0 @@
-{{define "overview"}}
-    <head>
-        {{template "header"}}
-    </head>
-    <body>
-        {{template "nav"}}
-        <div id="wrap">
-            <div class="container">
-                <h3>Existing galaxies</h3>
-                <table cellpadding="0" cellspacing="0" border="0" class="datatable table table-striped table-bordered">
-                    <thead>
-                        <tr>
-                            <th>Index</th>
-                            <th>Boundary</th>
-                            <th>Amounf of stars</th>
-                            <th>Range</th>
-                        </tr>
-                    </thead>
-
-                    <tbody>
-                        <tr class="gradeX">
-                            <td>1</td>
-                            <td></td>
-                            <td></td>
-                            <td></td>
-                        </tr>
-                        <tr class="gradeX">
-                            <td>2</td>
-                            <td></td>
-                            <td></td>
-                            <td></td>
-                        </tr>
-                        <tr class="gradeX">
-                            <td>3</td>
-                            <td></td>
-                            <td></td>
-                            <td></td>
-                        </tr>
-                    </tbody>
-
-                    <tfoot>
-                    </tfoot>
-                </table>
-            </div>
-        </div>
-
-        {{template "javascript"}}
-    </body>
-{{end}}
\ No newline at end of file
diff --git a/web/index.html b/web/index.html
deleted file mode 100644
index 51627b0..0000000
--- a/web/index.html
+++ /dev/null
@@ -1,41 +0,0 @@
-<!doctype html>
-<html lang="en">
-<head>
-    <!-- Required meta tags -->
-    <meta charset="utf-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
-
-    <!-- Bootstrap CSS -->
-    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
-
-    <title>Hello, world!</title>
-
-    <style>
-        .nav {
-            margin: 10px;
-        }
-    </style>
-</head>
-<body>
-    <nav>
-        <div class="nav nav-tabs" id="nav-tab" role="tablist">
-            <a class="nav-item nav-link active" id="nav-overview-tab" data-toggle="tab" href="#nav-overview" role="tab" aria-controls="nav-overview" aria-selected="true">Overview</a>
-            <a class="nav-item nav-link" id="nav-new-tree-tab" data-toggle="tab" href="#nav-new-tree" role="tab" aria-controls="nav-new-tree" aria-selected="false">New Tree</a>
-            <a class="nav-item nav-link" id="nav-add-stars-tab" data-toggle="tab" href="#nav-add-stars" role="tab" aria-controls="nav-add-stars" aria-selected="false">Add Stars</a>
-            <a class="nav-item nav-link" id="nav-draw-tree-tab" data-toggle="tab" href="#nav-draw-tree" role="tab" aria-controls="nav-contact" aria-selected="false">Draw Tree</a>
-        </div>
-    </nav>
-    <div class="tab-content" id="nav-tabContent">
-        <div class="tab-pane fade show active" id="nav-overview" role="tabpanel" aria-labelledby="nav-overview-tab">This is the main overview page!</div>
-        <div class="tab-pane fade" id="nav-new-tree" role="tabpanel" aria-labelledby="nav-new-tree-tab">Create a new tree!</div>
-        <div class="tab-pane fade" id="nav-add-stars" role="tabpanel" aria-labelledby="nav-add-stars-tab">Add some stars!</div>
-        <div class="tab-pane fade" id="nav-draw-tree" role="tabpanel" aria-labelledby="nav-draw-tree-tab">Draw one of the galaxies!</div>
-    </div>
-
-    <!-- Optional JavaScript -->
-    <!-- jQuery first, then Popper.js, then Bootstrap JS -->
-    <script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
-    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
-    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>
-</body>
-</html>
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