I am building a PB object in Haskell and I do not want to specify optional fields. Is this possible?
In the very simplest case, I have a header field that has a failure_message that I want empty in most cases. I have some code where a worker task responds with an OK status:
let repMsg = ProtoMsg.WorkerResponse.WorkerResponse {
header = ProtoMsg.ReqResponse.ReqResponse {
ProtoMsg.ReqResponse.status = Just ProtoMsg.Status.OK,
failure_message = Nothing
}
}
Is there a way to set all unspecified fields to Nothing some how? In this case it's not so bad, but when there are more optional fields it gets annoying.
You can make a record value that has the fields you want already set and then update that record.
noFailureMsg = ProtoMsg.ReqResponse.ReqResponse {
failure_message = Nothing
}
let repMsg = ProtoMsg.WorkerResponse.WorkerResponse {
header = noFailureMsg {
ProtoMsg.ReqResponse.status = Just ProtoMsg.Status.OK
}
}
I'm not completely sure this is what you are looking for.
Related
So I came across this general problem and didn't find an answer yet.
Problem: The input value can have optional variables, like the case below, group_memberships is an optional input, at the moment I make it an empty string input for this to work.
But if I comment it out like shown below and run it, I would get the error:
The given key does not identify an element in this collection value.
Basically it's complaining that I don't have list_of_users.test_user.group_memberships.Is there a way to tell terraform if the input is not declared, just ignore it? I know I can leave it the way it is but user can potentially have many optional values, and making lots of empty input doesn't really make sense.
Thanks! First post question, sorry about poor layout for the code : )
in my .tfvars file:
list_of_users = {
regular_user = {
email = "pdv#abc.com",
group_memberships = "regular_group"
},
test_user = {
email = "test#abc.com",
// group_memberships = "" <------ Currently can work if not comment out, looking for solution that I can remove those reduent empty declariation
},
admin_user = {
email = "admin#abc.com",
group_memberships = "admin_group"
}
}
in .tf file:
variable "list_of_users" {}
resource "user_api_from_provider" "user_generate" {
for_each = var.list_of_users
email = each.value["email"]
group_memberships = each.value["group_memberships"] !=""? [user_api_from_provider.group_generate[each.value["group_memberships"]].id] : null
}
There is support for this as a Terraform "experiment" (it's implemented, but could change or be removed in future versions). You have to declare in your module that you're using the experiment:
terraform {
# Optional attributes and the defaults function are
# both experimental, so we must opt in to the experiment.
experiments = [module_variable_optional_attrs]
}
And then you would use it in your case like this:
variable "list_of_users" {
type = map(object({
email = string
group_memberships = optional(string)
}))
}
Now, if group_membership isn't defined for a given user, that field will have the value of null, so you can now do:
resource "user_api_from_provider" "user_generate" {
...
group_memberships = each.value.group_memberships != null ? [user_api_from_provider.group_generate[each.value["group_memberships"]].id] : null
}
Alternatively, if you don't want to use the experiment, you should be able to do this (untested):
resource "user_api_from_provider" "user_generate" {
...
group_memberships = contains(each.value, "group_memberships") ? [user_api_from_provider.group_generate[each.value["group_memberships"]].id] : null
}
As of Terraform v1.3 the Optional Object Type Attributes feature is official, which means it is no longer an experiment and the syntax is considered stable.
As mentioned in previous comments, you can now do something like:
variable "list_of_users" {
type = map(object({
email = string
group_memberships = optional(string, "")
}))
}
In the above example, using the default value ("") allows the Terraform code in the project/module to function as if there is always a value even if it is omitted from the input variables.
I am using node-config in basically all my projects and most of the time I come across the problem of parsing booleans and numbers which are set as environment variables.
E.g.
default.js
module.exports = {
myNumber = 10,
myBool = true
}
custom-environment-variables.js
module.exports = {
myNumber = "MY_NUMBER",
myBool = "MY_BOOL"
}
Now, the obvious problem is that if I override the default values with custom values set as environment variables they will be a string value instead of a number or boolean value. So now, to make sure in my code that the types are correct. I always have to do type conversion and for booleans use a proper library e.g. yn. The problem is I have to do this conversion every time I use config.get() for example +config.get("myNumber") or yn(config.get("myBool")).
Is there a better and more elegant way to do this?
One solution I see would be to add a type property to an environment variable as it is done here with format. This would allow to do something like this...
custom-environment-variables.js
module.exports = {
myNumber = {
name: "MY_NUMBER",
type: "number"
},
myBool = {
name: "MY_BOOL",
type: "boolean"
}
}
node-config would handle the type conversions and there would be no need to do it all the time in the code when getting it. Of course there would be the requirement to implement a proper parser for booleans but those already exist and could be used here.
By default, environment variables will be parsed as string.
In node-config, we could override this behaviour with __format as shown below.
We don't need any additional libraries. Normal json datatypes like boolean, number, nested json etc., should work well.
Taking an easy to relate example.
config/default.json
{
"service": {
"autostart": false
}
}
custom-environment-variables.json
{
"service": {
"autostart": {
"__name": "AUTOSTART",
"__format": "json"
}
}
}
Now we can pass environment variables when we like to override and no type conversation should be needed for basic types.
This feature is now supported in node-config v3.3.2, see changelog
I use this method:
const toBoolean = (dataStr) => {
return !!(dataStr?.toLowerCase?.() === 'true' || dataStr === true);
};
You can add cases if you want 0 to resolve to true as well:
const toBoolean = (dataStr) => {
return !!(dataStr?.toLowerCase?.() === 'true' || dataStr === true || Number.parseInt(dataStr, 10) === 0);
};
I want to make sure that no search bar is displayed when the datasource of my table view is empty. (Makes sense, no? shouldn't that be default behaviour?)
Here's a piece of my code that tries (currently uncommented) different things to accomplish that, but somehow it doesn't work.
Can anybody advise me what I'm doing wrong? Let me know if you need more snippets.
messagesArray=loadMessages()
DispatchQueue.main.async {
if (self.messagesArray.count==0){
self.noMessageview.isHidden=false
//self.searchController.searchBar.isHidden = true
//self.searchController.isActive = false
} else{
self.noMessageview.isHidden=true
//self.searchController.searchBar.isHidden = false
//self.searchController.isActive = true
}
self.spinner.stopAnimating()
self.refreshControl.endRefreshing()
self.tableView.reloadData()
}
UPDATE:
I declare the search controller like this:
let searchController = UISearchController(searchResultsController: nil)
and in the ViewDidLoad I do:
navigationItem.searchController = searchController
I believe you are using iOS 11 because of setting UISearchController from navigationItem, Thus you can use the following code to remove it:
if #available(iOS 11.0, *) {
self.navigationItem.largeTitleDisplayMode = .never;
self.navigationItem.searchController = nil
} else {
// Fallback on earlier versions
self.navigationItem.titleView = nil
};
I had some problem and i think its iOS 11 bug, when removing the UISearchController, the view doesn't get adjusted thus i had to call this right before removing UISearchController.
self.navigationItem.largeTitleDisplayMode = .never;
Thats all.
It's difficult to explain the case by words, let me give an example:
var myObj = {
'name': 'Umut',
'age' : 34
};
var prop = 'name';
var value = 'Onur';
myObj[name] = value; // This does not work
eval('myObj.' + name) = value; //Bad coding ;)
How can I set a variable property with variable value in a JavaScript object?
myObj[prop] = value;
That should work. You mixed up the name of the variable and its value. But indexing an object with strings to get at its properties works fine in JavaScript.
myObj.name=value
or
myObj['name']=value (Quotes are required)
Both of these are interchangeable.
Edit: I'm guessing you meant myObj[prop] = value, instead of myObj[name] = value. Second syntax works fine: http://jsfiddle.net/waitinforatrain/dNjvb/1/
You can get the property the same way as you set it.
foo = {
bar: "value"
}
You set the value
foo["bar"] = "baz";
To get the value
foo["bar"]
will return "baz".
You could also create something that would be similar to a value object (vo);
SomeModelClassNameVO.js;
function SomeModelClassNameVO(name,id) {
this.name = name;
this.id = id;
}
Than you can just do;
var someModelClassNameVO = new someModelClassNameVO('name',1);
console.log(someModelClassNameVO.name);
simple as this
myObj.name = value;
When you create an object myObj as you have, think of it more like a dictionary. In this case, it has two keys, name, and age.
You can access these dictionaries in two ways:
Like an array (e.g. myObj[name]); or
Like a property (e.g. myObj.name); do note that some properties are reserved, so the first method is preferred.
You should be able to access it as a property without any problems. However, to access it as an array, you'll need to treat the key like a string.
myObj["name"]
Otherwise, javascript will assume that name is a variable, and since you haven't created a variable called name, it won't be able to access the key you're expecting.
You could do the following:
var currentObj = {
name: 'Umut',
age : 34
};
var newValues = {
name: 'Onur',
}
Option 1:
currentObj = Object.assign(currentObj, newValues);
Option 2:
currentObj = {...currentObj, ...newValues};
Option 3:
Object.keys(newValues).forEach(key => {
currentObj[key] = newValues[key];
});
I'm writing a mini-console of sorts and I'm trying to figure out how to extract things from a link. For example, in PHP this is a request variable
so:
http://somelink.com/somephp.php?variable1=10&variable2=20
Then PHP figures out the url parameters and assigns them to a variable.
How would I parse something like this in Swift?
So, given the string I'd want to take: variable1=10 and variable2=20 etc, is there a simple way to do this? I tried googling around but didn't really know what I was searching for.
I have a really horrible hacky way of doing this but it's not really extendable.
You’d be wanting NSURLComponents:
import Foundation
let urlStr = "http://somelink.com/somephp.php?variable1=10&variable2=20"
let components = NSURLComponents(string: urlStr)
components?.queryItems?.first?.name // Optional("variable1")
components?.queryItems?.first?.value // Optional("10")
You might find it helpful to add a subscript operator for the query items:
extension NSURLComponents {
subscript(queryItemName: String) -> String? {
// of course, if you do this a lot,
// cache it in a dictionary instead
for item in self.queryItems ?? [] {
if item.name == queryItemName {
return item.value
}
}
return nil
}
}
if let components = NSURLComponents(string: urlStr) {
components["variable1"] ?? "No value"
}