Struggling to build a JS/PHP validation function for my app - javascript

I have a web service that returns a JSON object when the web service is queried and a match is found, an example of a successful return is below:
{"terms":[{"term":{"termName":"Focus Puller","definition":"A focus puller or 1st assistant camera..."}}]}
If the query does not produce a match it returns:
Errant query: SELECT termName, definition FROM terms WHERE termID = xxx
Now, when I access this through my Win 8 Metro app I parson the JSON notation object using the following code to get a JS object:
var searchTerm = JSON.parse(Result.responseText)
I then have code that processes searchTerm and binds the returned values to the app page control. If I enter in a successful query that finds match in the DB everything works great.
What I can't work out is a way of validating a bad query. I want to test the value that is returned by var searchTerm = JSON.parse(Result.responseText) and continue doing what I'm doing now if it is a successful result, but then handle the result differently on failure. What check should I make to test this? I am happy to implement additional validation either in my app or in the web service, any advice is appreciated.
Thanks!

There are a couple of different ways to approach this.
One approach would be to utilize the HTTP response headers to relay information about the query (i.e. HTTP 200 status for a found record, 404 for a record that is not found, 400 for a bad request, etc.). You could then inspect the response code to determine what you need to do. The pro of this approach is that this would not require any change to the response message format. The con might be that you then have to modify the headers being returned. This is more typical of the approach used with true RESTful services.
Another approach might be to return success/error messaging as part of the structured JSON response. Such that your JSON might look like:
{
"result":"found",
"message":
{
"terms":[{"term":{"termName":"Focus Puller","definition":"A focus puller or 1st assistant camera..."}}]}
}
}
You could obviously change the value of result in the data to return an error and place the error message in message.
The pros here is that you don't have to worry about header modification, and that your returned data would always be parse-able via JSON.parse(). The con is that now you have extra verbosity in your response messaging.

Related

WP REST API ERROR 401 While trying to fetch image from wp:featuredmedia

I'm trying to fetch featured image from my published post but it seems impossible! I get
an error :( that's the code:
function fetchSlideShow(){
let endpoint = "http://loreleiheckmann.com/wordpress/wordpress/wp-json/wp/v2/Vinyls?_embed";
fetch(endpoint)
.then(e => e.json())
.then(showSlideShow);
}
function showSlideShow(data){
console.log(data);
data.forEach(showSingleSlide);
showSlides();
}
function showSingleSlide(aSlide) {
let template = document.querySelector(".slide_template").content;
let clone = template.cloneNode(true);
console.log(aSlide);
clone.querySelector("img").setAttribute("src", aSlide._embedded["wp:featuredmedia"]
[0].media_details.source_url);
let SlideList = document.querySelector("#SlideList");
SlideList.appendChild(clone);
}
While going to the array I see error 401 :( and moreover: Cannot read property 'source_url' of undefined" I don't know what I'm doing wrong .. any insights?
HERE ARE THE ERRORS -> 401 ON CONSOLE + PROBLEM WITH URL.:
Please try changing your url in the endpoint variable:
let endpoint = "http://loreleiheckmann.com/wordpress/wordpress/wp-json/wp/v2/posts?per_page=20&_embed=wp:featuredmedia
If you need more data you can add them with a comma:
wp-json/wp/v2/posts?per_page=20&_embed=wp:term,wp:featuredmedia
Post per page is optional, but I would prefer having that set.
And you should write what image size you need. That way rest api will give you the right source url:
_embedded['wp:featuredmedia']['0'].media_details.sizes.medium_large.source_url
I think it would also be better practice if you use an ssl certificate, there are free by "Let's encrypt".
EDIT:
Your screenshot shows the rest api message:
wp:featuredmedia: Array(1)
0:
code: "rest_forbidden"
data: {status: 401}
message: "Sorry, you are not allowed to do that."
So the 401 status code means: unauthorised
Seems like you are not allowed to access the data via rest api.
There could be multiple reasons for that:
The image is attached to an unpublished post. The post may have the status "private" or "draft", and therefore is not public available.
Your post (and attached image) is not available for not logged in users. If there is a restriction to view your code, this also applies to rest api.
Maybe you are using some kind of membership plugin that restricts the wp rest-api. Try deactivating all plugins if one of them affects the behaviour.
You have added some custom code to restrict access rest api access.
If nothing works for you, you should look into your database and check the medias post_status.
I think it is working fine, but you do not have access to view the posts data. This is what the 401 error indicates.
To whom it may concern - In the end, I added image in WP by custom post type ( I gave up wp:featured media - I wasn't able to fetch it.) Afterward I added a code to JS -> b.querySelector(".img").setAttribute("src", a.acf.image.url); so it works:)

AngularJs bookmarkable url and query parameters

I'm trying to fix one mistake which one of the previous developer has did. Currently in project we have half-bookmarkable pages. Why half? Because if token has expired user will be redirect to resourse where he has to provide his credentials and on success he will be redirect to previous resource which he has used before. Sounds good for now. The problem here is next, some of resources have server side filtering and highly complicated logic which comes in the end to the one object like this:
param = {
limit: 10,
offset: 0,
orderBy: 'value',
query: 'string query can include 10 more filters'
};
then thru the service it sends a request to the end point
var custom = {};
function data(param) {
custom.params = param;
return $http.get('/data_endpoint', custom)
.then(function (response) {
return response.data;
});
From this part request works fine and response is correct but url isn't. User cannot store current url with search params because url doesn't have it and if user will try to get back to previous page with applied filters he won't be able to do that.
Also there is interceptor in this application, which add one more query param to every api request, because every api request requires some specific validation. This param is always the same.
I have tried to add $location.search(param) exactly to this data service but it breaks the app with infinity loop of login / logout looping, because interceptor stops working and all other request are sending without special query param
Then I thought to add this params inside interceptor like this:
config.params.hasOwnProperty('query') ? $location.search(config.params) : $location.search();
But it still breaks app to infinity loop.
This method adds query to url but doesn't allow to modify it, so if user applied additional filtering, it doesn't send new modified request but sends old one.
if (config.params.hasOwnProperty('query')){
for (var key in config.params){
$location.search(key, config.params[key])
}
}
That's why I decided to ask question here, probably somebody gives an advice how to solve this problem. Thanks in advance.

Use JS to execute MySQL queries and the security issues it involves

I've been searching around the internet for a way to define a query in JavaScript, pass that query to PHP. Let PHP set up a MySQL connection, execute the query and return the results json encoded.
However my concern is with the security of this method since users could tamper with the queries and do things you don't want them to do or request data you do not want them to see.
Question
In an application/plugin like this, what kind of security measures would you suggest to prevent users from requesting information I don't want them to?
Edit
The end result of my plugin will be something like
var data = Querier({
table: "mytable",
columns: {"column1", "column2", "column3"},
where: "column2='blablabla'",
limit: "10"
});
I'm going to let that function make an AJAX request and execute a query in PHP using the above data. I would like to know what security risks this throws up and how to prevent them.
It's unclear from your question whether you're allowing users to type queries that will be run against your database, or if your code running in the browser is doing it (e.g., not the user).
If it's the user: You'd have to really trust them, since they can (and probably will) destroy your database.
If it's your code running in the browser that's creating them: Don't do that. Instead, have client-side code send data to the server, and formulate the queries on the server using full precautions to prevent SQL Injection (parameterized queries, etc.).
Re your update:
I can see at least a couple issues:
Here's a risk right here:
where: "column2='blablabla'"
Now, suppose I decide to get my hands on that before it gets sent to the server and change it to:
where: "column2=');DROP TABLE Stuff; --"
You can't send a complete WHERE clause to the server, because you can't trust it. This is the point of parameterized queries:
Instead, specify the columns by name and on the PHP side, be sure you're doing correct handling of parameter values (more here).
var data = Querier({
table: "mytable",
columns: {"column1", "column2", "column3"},
where: {
column2: {
op: '=',
value: 'blablabla'
}
}
limit: "10"
});
Now you can build your query without blindly trusting the text from the client; you'll need to do thorough validation of column names, operators, etc.
Exposing information about your scheme to the entire world is giving up information for free. Security is an onion, and one of the outer layers of that onion is obscurity. It's not remotely sufficient unto itself, but it's a starting point. So don't let your client code (and therefore anyone reading it) know what your table names and column names are. Consider using server-side name mapping, etc.
Depending on how you intend to do, you might have a hole bigger than the one made in this economy or no hole at all.
If you are going to write the query on client-side, and send to php, I would create a user with only select, insert, delete and update, without permissions to access any other database.
Ignore this if you use SQlite.
I advise against this!
If you build the query on server-side, just stuff to the server the data you want!
I would change the code into something like this:
var link = QuerierLink('sql.php');//filename to use for the query
var data = Querier('users',link);//locks access to only this table
data.select({
columns: ['id','name','email'],
where: [
{id:{'>':5}},
{name:{'like':'%david%'}}
],
limit:10
});
Which, on server-side, would generate the query:
select `id`,`name`,`email` from `db.users` where `id`>5 and `name` like '%david%' limit 10
This would be a lot better to use.
With prepared statements, you use:
select `id`,`name`,`email` from `db.users` where `id`>:id and `name` like :name limit 10
Passing to PDO, pseudo-code:
$query='select `id`,`name`,`email` from `'.$database_name.'.users` where `id`>:id and `name` like :name limit 10';
$result=$PDO->exec($query,array(
'id'=>5,
'name'=>'%david%'
)
);
This is the prefered way, since you have more control over what is passed.
Also, set the exact database name along the name of the table, so you avoid users accessing stuff from other tables/databases.
Other databases include information_schema, which has every single piece of information from your entire databasem, including user list and restrictions.
Ignore this for SQlite.
If you are going to use MySQL/MariaDB/other you should disable all read/write permissions.
You really don't want anyone writting files into your server! Specially into any location they wish.
The risk: They have a new puppy for the attackers to do what they wish! This is a massive hole.
Solution: Disable FILE privileges or limit the access to a directory where you block external access using .htaccess, using the argument --secure_file_priv or the system variable ##secure_file_priv.
If you use SQlite, just create a .sqlite(3) file, based on a template file, for each client connecting. Then you delete the file when the user closes the connection or scrap every n minutes for files older than x time.
The risk: Filling your disk with .sqlite files.
Solution: Clear the files sooner or use a ramdisk with a cron job.
I've wanted to implement something like this a long ago and this was a good way to exercice my mind.
Maybe I'll implement it like this!
Introducing easy JavaScript data access
So you want to rapidly prototype a really cool Web 2.0 JavaScript application, but you don't want to spend all your time writing the wiring code to get to the database? Traditionally, to get data all the way from the database to the front end, you need to write a class for each table in the database with all the create, read, update, and delete (CRUD) methods. Then you need to put some marshalling code atop that to provide an access layer to the front end. Then you put JavaScript libraries on top of that to access the back end. What a pain!
This article presents an alternative method in which you use a single database class to wrap multiple database tables. A single driver script connects the front end to the back end, and another wrapper class on the front end gives you access to all the tables you need.
Example/Usage
// Sample functions to update authors
function updateAuthorsTable() {
dbw.getAll( function(data) {
$('#authors').html('<table id="authors"><tr><td>ID</td><td>Author</td></tr></table>');
$(data).each( function( ind, author ) {
$('#authors tr:last').after('<tr><td>'+author.id+'</td><td>'+author.name+'</td></tr>');
});
});
}
$(document).ready(function() {
dbw = new DbWrapper();
dbw.table = 'authors';
updateAuthorsTable();
$('#addbutton').click( function() {
dbw.insertObject( { name: $('#authorname').val() },
function(data) {
updateAuthorsTable();
});
});
});
I think this is exactly what you're looking for. This way you won't have to build it yourself.
The more important thing is to be careful about the rights you grant to your MySQL user for this kind of operations.
For instance, you don't want them to DROP a database, nor executing such request:
LOAD DATA LOCAL INFILE '/etc/passwd' INTO TABLE test FIELDS TERMINATED BY '\n';
You have to limit the operations enabled to this MySQL user, and the tables he has accessed.
Access to total database:
grant select on database_name.*
to 'user_name'#'localhost' identified by 'password';
Access to a table:
grant select on database_name.table_name
to 'user_name'#'localhost' identified by 'password';
Then... what else... This should avoid unwanted SQL injection for updating/modifying tables or accessing other tables/databases, at least, as long as SELECT to a specific table/database is the only privillege you grant to this user.
But it won't avoid an user to launch a silly bad-performance request which might require all your CPU.
var data = Querier({
table: "mytable, mytable9, mytable11, mytable12",
columns: {"mytable.column1", "count(distinct mytable11.column2)",
"SUM(mytable9.column3)"},
where: "column8 IN(SELECT column7 FROM mytable2
WHERE column4 IN(SELECT column5 FROM mytable3)) ",
limit: "500000"
});
You have to make some check on the data passed if you don't want your MySQL server possibly down.

javascript - make facebook page post

I am not using the Javascript SDK because that is client-side whereas I'm making a server-side call.
I want to make a page post so that I can make an ad creative with it. I can do the call perfectly fine in the Graph API Explorer tool, but I cannot make the same call (with the same long-lived access tokens that continue to work in the Graph Explorer) from Javascript. Here is my code:
tok = <valid and never expiring user token>;
var pg_tok = <valid and never expiring page token>;
var act_id = <account_id>;
var pg_id = <page_id>;
var call_to_action = 'INSTALL_MOBILE_APP';
var fb_app_url = 'https://itunes.apple.com/us/app/id284882215';
var msg = 'Test creative, ya see';
var pic_url = 'https://s3.amazonaws.com/<path_to_my_image>';
var ROOT = 'https://graph.facebook.com/';
var pagepost_endpoint = ROOT+pg_id+'/feed';
console.log(pagepost_endpoint);
var pagepost_params = {
access_token: pg_tok,
call_to_action: {
type: call_to_action,
value: {link: fb_app_url}
},
message: msg,
picture: pic_url,
published: false
};
console.log(pagepost_params);
var pagepost_res = HTTP.post(pagepost_endpoint, {params: pagepost_params});
console.log(pagepost_res);
I have played around a bunch with params vs. data for where pagepost_params goes in the HTTP.post that is giving the error (that is Meteor's HTTP btw).
-Putting everything in params gives the error: {"error":{"type":"Exception","message":"No Call To Action Type was parseable. Please refer to the call to action api documentation","code":1373054,"is_transient":false}}.
-Putting everything in data gives the error: {"error":{"message":"(#200) This API call requires a valid app_id.","type":"OAuthException","code":200}}.
-Putting access_token in params and everything else in data gives the error: {"error":{"message":"Invalid parameter","type":"FacebookApiException","code":100,"error_subcode":1349125}}.
One more clue for everyone, if I change the HTTP.post to HTTP.get, and just put access_token in params and include no other parameters (in params or in data), the call succeeds and I see past posts I have made on this page through the Graph Explorer (only the ones with published: true, though), so the access token and endpoint do work, just something is faulty about POST-ing instead of GET-ing and the specific parameters I'm using.
Have you tried posting to /photos instead of /feed? The error subcode is the same as mentioned here Posting to facebook wall using graph api
Hope this helps
Turned out to be an issue with Meteor's HTTP. It does not handle nested JSON very well, and we're going to submit a pull request for that. But for those seeing this, the important thing to take away is that the call_to_action may not be a valid JSON object, and even if it is, it may not be being stringified/parsed as expected. My fix was using request.post instead of HTTP.post. (then instead of params or data, you use form. look up node's request https://github.com/mikeal/request)

Generate card_error in stripe.js while testing

I dont know this can be done or not, but i was wondering is there any way to generate card_error on stripe for testing?
To clarify my question here's what I want to do:
Stripe provides varieties of card numbers for testing purposes
(here). Along with this it also provides methods for form
validation(eg. I enter 34/2013 as expiry date and i'll get invalid
date error by validation then and there).
But i want to create a situation where a
user enters an expiry date which is a valid date (say 12/2015) but
its not the real expiry date of the card, so that on sending this
information to stripe, i recieve an error in json form named
card_error. (here)
How can this be done?
There are two approaches you could take to this.
You pass the stripe API call a callback function. This callback is the unit of code that you want to test with the card_error type of response
'test card_error is handled correctly': function() {
var response = {
type: 'card_error',
message: 'The human readable message',
code: 'invalid_cvc'
myStripeCallback(response)
// Make assertions down here about what happened when
// you called the function with the error message
// Maybe it emailed you, maybe it displayed a message
// to the user. I would then probably make another test
// for each `code` that I cared about.
}
The second approach would be to mock out the stripe api call entirely. Check that it was called with the right arguments and then call the provided callback with the error response that you wanted to deal with in that test.
Im sorry, turned out to be stripe already has special codes for this purpose. I over looked that part of the page despite going through the page several times.. stupid me! :-/
Anyways here are the codes:
source: https://stripe.com/docs/testing

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