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JSON + Node.js - Jeton inattendu o

Je viens de commencer à travailler avec des objets node.js et json dans mon cours universitaire. L'une de nos missions cette semaine était de créer quelques objets json et d'extraire des parties de l'objet dans une page html. Je pensais avoir une bonne compréhension de la façon de procéder, mais je rencontre une erreur lorsque j'essaie de démarrer le nœud. Si je supprime l'objet colleges et l'instruction parse, le nœud fonctionne correctement.

Voici l'erreur que j'obtiens lorsque j'exécute "node index.js":

undefined:1
[object Object],[object Object],[object Object],[object Object],[object Object
 ^
SyntaxError: Unexpected token o
at Object.parse (native)
at Object.<anonymous> (/home/ubuntu/node_stuff/node_json/requestHandlers.js:13:20)
at Module._compile (module.js:449:26)
at Object.Module._extensions..js (module.js:467:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Module.require (module.js:362:17)
at require (module.js:378:17)
at Object.<anonymous> (/home/ubuntu/node_stuff/node_json/index.js:3:23)
at Module._compile (module.js:449:26)

Et voici le code avec lequel je travaille.

var querystring = require("querystring"),
fs = require("fs"),
formidable = require("formidable");

var colleges = [
{"name":"A-B Tech","street":"340 Victoria Road","city":"Asheville","state":"NC","Zip":"28801","phone":"828-254-1921"},
{"name":"UNC Asheville","street":"1 University Heights","city":"Asheville","state":"NC","Zip":"28804","phone":"828-251-6600"},
{"name":"UNC Charlotte","street":"9201 University City Blvd","city":"Charlotte","state":"NC","Zip":"28223","phone":"704-687-8622"},
{"name":"Western Carolina","street":"North Carolina 107","city":"Cullowhee","state":"NC","Zip":"28723","phone":"877-928-4968"},
{"name":"NC State","street":"2200 Hillsborough","city":"Raleigh","state":"NC","Zip":"27695","phone":"919-515-2011"}
];

var college = JSON.parse(colleges);

function abtech(response) {
console.log("Request handler 'abtech' was called.");

var body = '<html>'+
'<head>'+
'<meta http-equiv="Content-Type" '+
'content="text/html; charset=UTF-8" />'+
'</head>'+
'<body>'+
'<ul>'+
'<li>' + college[0].name + '</li>'+
'<li>' + college[0].street + '</li>'+
'<li>' + college[0].city + ' ' + college[0].state + ' ' + college[0].Zip + '</li>'+
'<li>' + college[0].phone + '</li>'+
'</ul>'+
'</body>'+
'</html>';

response.writeHead(200, {"Content-Type": "text/html"});
response.write(body);
response.end();
}

function unca(response) {
console.log("Request handler 'abtech' was called.");

var body = '<html>'+
'<head>'+
'<meta http-equiv="Content-Type" '+
'content="text/html; charset=UTF-8" />'+
'</head>'+
'<body>'+
'<ul>'+
'<li></li>'+
'<li></li>'+
'<li></li>'+
'<li></li>'+
'</ul>'+
'</body>'+
'</html>';

response.writeHead(200, {"Content-Type": "text/html"});
response.write(body);
response.end();
}

function home(response) {
console.log("Request handler 'home' was called.");

var body = '<html>'+
'<head>'+
'<meta http-equiv="Content-Type" '+
'content="text/html; charset=UTF-8" />'+
'</head>'+
'<body>'+
'<h1>Welcome to College</h2>'+
'<p>Where would you like to visit?</p>'+
'<ul>'+
'<li><a href="/colleges">Colleges</a></li>'+
'<li><a href="/hours">Hours of Operation</a></li>'+ 
'<li><a href="/start">Upload a Photo</a></li>'+
'<li><a href="/show">View Gallery</a></li>'+
'</ul>'+
'</body>'+
'</html>';

response.writeHead(200, {"Content-Type": "text/html"});
response.write(body);
response.end();
}

function colleges(response) {
console.log("Request handler 'colleges' was called.");

var body = '<html>'+
'<head>'+
'<meta http-equiv="Content-Type" '+
'content="text/html; charset=UTF-8" />'+
'</head>'+
'<body>'+
'<h1>Colleges</h2>'+
'<ul>'+
'<li><a href="/abtech">A-B Tech</a></li>'+
'<li><a href="/unca">UNC Asheville</a></li>'+
'<li><a href="/uncc">UNC Charlotte</a></li>'+
'<li><a href="/wcu">Western Carolina</a></li>'+
'<li><a href="/ncsu">NC State</a></li>'+
'</ul>'+
'</body>'+
'</html>';

response.writeHead(200, {"Content-Type": "text/html"});
response.write(body);
response.end();
}

function hours(response) {
console.log("Request handler 'gallery' was called.");

var body = '<html>'+
'<head>'+
'<meta http-equiv="Content-Type" '+
'content="text/html; charset=UTF-8" />'+
'</head>'+
'<body>'+
'<h1>Hours of Operation</h2>'+
'<table>'+
'<tr><td>Monday - Thursday</td><td>9 a.m. - 7 p.m.</td></tr>'+
'<tr><td>Friday</td><td>9 a.m. - 5 p.m.</td></tr>'+
'<tr><td>Saturday</td><td>9 a.m. - 12 p.m.</td></tr>'+
'</table>'+
'</body>'+
'</html>';

response.writeHead(200, {"Content-Type": "text/html"});
response.write(body);
response.end();
}


function start(response) {
console.log("Request handler 'start' was called.");

var body = '<html>'+
'<head>'+
'<meta http-equiv="Content-Type" '+
'content="text/html; charset=UTF-8" />'+
'</head>'+
'<body>'+
'<h1>Upload a file</h2>'+
'<p>It will be shown on the /show url after</p>'+
'<form action="/upload" enctype="multipart/form-data" '+
'method="post">'+
'<input type="file" name="upload" multiple="multiple">'+
'<input type="submit" value="Upload file" />'+
'</form>'+
'</body>'+
'</html>';

response.writeHead(200, {"Content-Type": "text/html"});
response.write(body);
response.end();
}

function upload(response, request) {
console.log("Request handler 'upload' was called.");

var form = new formidable.IncomingForm();
console.log("about to parse");
form.parse(request, function(error, fields, files) {
console.log("parsing done");

/* Possible error on Windows systems:
   tried to rename to an already existing file */
fs.rename(files.upload.path, "/home/ubuntu/node_stuff/node_assignment/test.jpg", function(err) {
  if (err) {
    fs.unlink("/home/ubuntu/node_stuff/node_assignment/test.jpg")
    fs.rename(files.upload.path, "/home/ubuntu/node_stuff/node_assignment/test.jpg");
  }
});
response.writeHead(200, {"Content-Type": "text/html"});
response.write("received image:<br/>");
response.write("<img src='/show' />");
response.end();
});
}

function show(response) {
console.log("Request handler 'show' was called.");
fs.readFile("/home/ubuntu/node_stuff/node_assignment/test.jpg", "binary", function(error, file) {
if(error) {
  response.writeHead(500, {"Content-Type": "text/plain"});
  response.write(error + "\n");
  response.end();
} else {
  response.writeHead(200, {"Content-Type": "image/jpg"});
  response.write(file, "binary");
  response.end();
}
});
}

exports.start = start;
exports.upload = upload;
exports.show = show;
exports.home = home;
exports.colleges = colleges;
exports.hours = hours;
exports.abtech = abtech;

Tout indice sur ce que je fais mal serait très apprécié. Mon instructeur est difficile à joindre pendant le week-end, donc je n'ai pas vraiment d'autre endroit où me tourner. Je vous remercie.

javascripthtmljsonnode.js
24
Daniel

Votre variable colleges est déjà un objet JavaScript valide. Vous n'êtes pas obligé d'utiliser JSON.parse dessus.

JSON.parse attend un String comme premier argument, mais vous fournissez un Object. Ainsi, il est contraint à un String ressemblant à celui que vous voyez dans le message d'erreur.

Pour le reste de votre code, vous voudrez peut-être jeter un œil à Express ou Zappa pour pouvoir écrire le code un peu plus compact;)

36
Tharabas

la solution consiste à utiliser JSON.stringify comme suit

var target=JSON.parse(JSON.stringify(source));
0
Badr Bellaj