So I am trying to sort out variable scope. Below is a simple snippet of code:
const params = {
versions: versions,
user: user,
statsParams: statsParams,
csrfToken: csurf.createToken(req),
};
res.render("server/edit", params);
return;
Now the values that are in the params object are available in the ejs page for use. What I am seeing is that other variables that precede this code block also seem to be available in the ejs file as well not just the ones passed via the param object. Is this expected behavior? I have looked on the ejs website and it doesn't speak of variable scope.
Brad
What you are doing with your code is rendering the page using ejs and passing the params object to the page. By passing it to the page you can render the page with access to the variables you passed in using the following tags : <%= variable =>
In terms of scope, you have now rendered the page to have access to all the variables you have passed in under the name params during the operation : res.render("server/edit", params);
If you have passed other variables through api calls to your backend you will also be able to access them in their according scope, but unless you include other variables to be passed as parameters you will not be able to access other variables from your backend.
Example :
--> userController.js
var outOfScope = True;
const params = {
versions: versions,
user: user,
statsParams: statsParams,
csrfToken: csurf.createToken(req),
};
res.render("index", params);
return;
--> index.html
...
<h1>Variable</h1>
<p><%= params.user %></p>
...
This will not work
...
<h1>Variable</h1>
<p><%= outOfScope %></p>
...
If you still have issues regarding access to variables you haven't passed it is possible you may have included them from another file by accident (ex. a header that is included).
I hope this helps, but if you are having trouble with specific variables please include them in your question as well as how you are accessing them.
Related
I have a strange error with mongoose deleteOne() function. Today I wanted to work on my project and got an error while deleting an item from a collection. It simply doesn't delete the document until I use a hardcoded parameter for the options object like this:
const { deletedCount } = await Model.deleteOne({symbol: 'hardcoded'})
// results in deletedCount = 1
But if I try to use a dynamic string like:
const test = 'dynamic'
const { deletedCount } = await Model.deleteOne({symbol: test})
// results in deletedCount = 0
It does no longer delete the document from my collection. The strange thing is yesterday it worked fine and deleted the item.
I tried one other thing I read regarding errors with deleteOne():
const { deletedCount } = await Model.deleteOne({symbol: JSON.stringifiy(symbol)})
But this doesn't work, too.
Does anyone have an idea what's going wrong?
I always default to using ids whenever possible to make sure there's no mistake in the data I am targeting with a given operation.
So in this case that would mean using findByIdAndDelete() instead.
If I don't know the id of the document I'm trying to delete, then only I'd use findOneAndDelete() or deleteOne(), as you have, with something other than an id to identify the document I'm looking for.
Are you certain that the key-value pair you're passing to the function exists in your database?
Problem solved. I accidentally added an additional space character at the end of the string. This is very strange because the error was there since the beginning of my project and yesterday it worked.
So for everyone who might have a similar problem:
I have a ejs template file where I render a html element like this:
<div id="<%= symbol %> ">
Then in my event handler for requesting the server to deleting one item from my list I use the id attribute as a request parameter in the body. In the route handler this parameter is passed to mongoose:
const { symbol } = req.body
const { deletedCount } = await Model.deleteOne({ symbol })
As I mentioned. In the template file after the last ejs seperator there is an addional space character that caused the error. I spotted this issue by making a copy of the monoogse query and than logged it to the console. There I could see the wrong condition parameter.
We can use variables in aura components to concatenate some expression, we have to use variable name itself in lwc components, while looping how to change the lwc comp variable in js file.
I tried to access the dom using this.template.querySelector(); but this one is only giving the value if I use a rendered callback.
<template for:each={documentLinks} for:item="item">
//here I need to pass the item.ContentDocument.LatestPublishedVersionId to the end of a URL string
<img src={item.srcUrl} alt="PDF"/>
we can modify the returned data from apex but the data is proxy we cannot modify it.
One of the possible solutions to change the URL on the dom when it loads is to change the returned data from the server. here, In lightning web components the returned data is a proxy object, only readable. so we have to clone it(there are multiple ways to clone it), to make any changes. but here what I did.
therefore, overrides array is going to be the new data.
let overrides = [];
let newData = {
contentDocs: data[i],
srcUrl: '/sfc/servlet.shepherd/version/renditionDownloadrendition=thumb120by90&versionId=' + data[i]['ContentDocument']['LatestPublishedVersionId']
};
makeLoggable(newData);
overrides.push(newData);
function makeLoggable(target) {
return new Proxy(target, {
get(target, property) {
return target[property];
},
set(target, property, value) {
Reflect.set(target, property, value);
},
});
}
To access a unique identifier for Bixby, I'm trying to access the contactId field within the contact library (which is also viv.self I think?). I tried using the code snippet found in the docs here, but I'm getting some errors.
Code Snippet (Source)
text (Name) {
extends (contact.StructuredName)
}
Errors
ERROR: invalid capsule alias contact
ERROR: unknown super-type: contact.contactId
I would ultimately like to do something like this
integer (Identifier) {
extends (contact.ContactId)
}
Would appreciate any help on accessing this data!
I ended up finding another way to get a device identifier from these docs. There's also a sample capsule here.
In your corresponding JavaScript file, access the $vivContext.locale parameter to return the locale information.
module.exports.function = function accessVivContext (dummyInput, $vivContext) {
var result = "Testing Access vivContext..."
// See docs for all the properties of $vivContext
result = $vivContext.userId
return result
}
You would then need to configure your endpoints for this action like below, including making sure that you set up the proper accepted-inputs for your endpoint:
action-endpoint (AccessVivContext) {
accepted-inputs (dummyInput, $vivContext)
local-endpoint ("AccessVivContext.js")
}
I'm doing some URL verification between a Shopify site and my app. On Shopify, in a .liquid file, I'm creating an HMAC value using Shopify's built in hmac_sha256 string filter. I'm using a secret key and a Twitch user ID which I've stored in a customer tag.
The hash value is passed as a query parameter to my app, which uses the crypto module in node.js to generate a hash and compare it with the hash from the url.
Things get strange here: In the .liquid file, when I type the Twitch ID directly into the string filter, the hash value generated by the .liquid file is the same value my app generates, and everything looks good:
{{ "12345678" | hmac_sha256: "secret_key" }}
However, when I pass the same Twitch ID as a variable into the string filter, the hash value the liquid file generates is different than the first time:
{{ twitchId | hmac_sha256: "secret_key" }}
I've already tried removing whitespace and newline characters from the Twitch ID variable just in case there were any. I don't even have a guess as to what the problem could be. Maybe the variable (which is a string) is encoded differently than when I type it in directly?
For reference, the javascript code checking for matching hashes:
// Get query string params:
const { hash, twitchId } = req.query;
console.log('Twitch ID in query: ' + twitchId);
// Verify user
const generatedUserHash = crypto
.createHmac('sha256', userVerifySecret)
.update(twitchId)
.digest('hex');
console.log('Passed hash: ' + hash + ' Generated hash: ' + generatedUserHash);
if (generatedUserHash == hash) {
return true;
} else {
return false;
}
You need to show how you are assigning the ID to the variable. Without seeing that, there is no way to validate your question.
I did a quick test, and proved I get the same HMAC with a string and a variable, so it must be that you are doing something weird in your assignment:
<h1>{{ "12345678" | hmac_sha256: "secret_key" }}</h1>
{% capture fizz %}12345678{% endcapture%}
<h1>{{ fizz | hmac_sha256: "secret_key"}}</h1>
Produces:
fcfebc0d424982ce8c7a986264beb0d4b1de44507501451e142236404e5b9778
fcfebc0d424982ce8c7a986264beb0d4b1de44507501451e142236404e5b9778
Turns out my variable twitchId was getting instantiated after I was trying to use it in the sha256 filter. I was instantiating it in my theme.liquid file, and I was trying to access it in a liquid file in my app (the request from the Shopify site is responded to with a liquid file).
I guess I wrongly assumed the theme.liquid file is loaded before the file in my response to Shopify. I assumed this because javascript variables I instantiate in my theme.liquid file are available in my response liquid file (I think this has something to do with liquid variables being created server-side and javascript variables being created client-side).
I am now instantiating the twitchId variable in my response liquid file. So that solved it.
I first get the data from sql then pass it into handlebars.
Inside the tag in .handlebars/using view.js, I want to access doctors, but i keep getting[object][object]. I tried json.stringifying it before but still no luck. What is the best way to do this?
umd.matchDocs(val2, function(data) {
console.log(data);
var renderDocs = {
doctors: data
}
res.render("dashboard", renderDocs);
});
After passing object to handlebars, how can I access that object in script tag?
No, not by default. But you can make the data available manually if you want.
Data you pass to handlebars rendering operation is available during the rendering operation only. If you want to be able to access some of that data later in client-side <script> tags, then you can "render" Javascript variables into the <script> tags that contain the desired data.
Remember when rendering data into Javascript variables, you need to render the actual Javascript text (converting to JSON will often create the text for you).
In your specific example, you could do something like this in your rendering code:
umd.matchDocs(val2, function(data) {
console.log(data);
var renderDocs = {
doctors: JSON.stringify(data)
}
res.render("dashboard", renderDocs);
});
And, then in the template:
<script>
var doctors = {{{doctors}}};
</script>
Then, this array of doctors would be available to the Javascript in your page.
In case you haven't seen the triple braces like shown above, that's to tell handlebars to skip any HTML escaping in the data (because this isn't HTML).