I'm not sure if the title accurately explains what I'm looking to do so I'll try to give as many details as I can.
I have a struct with nested structs that I am marshalling and sending out to an API. There are some requests that require my lowest level struct to be empty and I need its parent parameter to equal an empty array instead of null. If I use omitempty on the parameter, it will completely remove it from my request and the request will fail. If I use omitempty on the parameter's parameters, it causes the value to be null and the request will fail.
Here are the structs I am using for the request:
// SubscribeRequest is the top level wrapper for ICWS request bodies
SubscribeRequest struct {
ClientStateIsFresh bool `json:"clientStateIsFresh"`
StatisticKeys []StatisticKey `json:"statisticKeys"`
}
// StatisticKey is a value we want to pull from ICWS reporting
StatisticKey struct {
StatisticIdentifier string `json:"statisticIdentifier"`
ParameterValueItems []Parameter `json:"parameterValueItems"`
}
// Parameter is a filter applied when pulling statistics
Parameter struct {
ParameterTypeID string `json:"parameterTypeId"`
Value string `json:"value"`
}
And I need the marshalled JSON to look like this:
{
"clientStateIsFresh":true,
"statisticKeys":
[
{
"statisticIdentifier":"inin.system.interaction:ActiveCalls",
"parameterValueItems":
[
]
}
]
}
If I have anything other than this, the request fails. I don't get any errors, but it doesn't return any usable data. Any suggestions on how to accomplish this?
*Note: I did try using []*Parameter instead of []Parameter, but it gave me the same result.
If you want an empty array, you have to provide an empty slice.
StatisticKey{
StatisticIdentifier: "id.string",
ParameterValueItems: []Parameter{},
}
Related
I have an object of $person as below:
$person = Person::where('id', $id)->first();
According to which $person exists or not I load other data:
if($person) {
$person->family_members = FamilyMemberController::FamilyMemberOf($person->id);
} else {
$person->family_members = [];
}
In the view file, I check the $person->family_members if not empty and exists to add a generated value :
if(!empty(array_filter($person->family_members))) {
// my code
}
But it throws an error:
array_filter(): Argument #1 ($array) must be of type array, Illuminate\Database\Eloquent\Collection given
I need to check this $person->family_members to make sure whether it's an array or a collection is not empty.
Writing code for if array do something if collection do something is the wrong way of implementation.
You can do two things.
use both returns as collection()
or either use both returns as an array[]
If collection
else {
$person->family_members = collect();
}
If array
use ->toArray() at the end of Eloquent. Check this answer
As well, I think you are confused with array_filter(). Maybe you are searching for in_array() or contains()
Use count method
if(count($person->family_members)>0){
//your code
}
We don't know your code, but given the error, it's safe to assume your method returns a Collection. You can see available methods in the docs. However, if you need it as array, all you need to do is call ->toArray() on the result Collection. Then you can use array_filter.
What about just doing
if(!$person->family_members){
// your code here
}
or
if($person->family_members){
// your code here
} else {
// code of "if it's empty" goes here
}
You can use the count() function to return a count of an index. ex
if(count($person->family_members)){
//do your true algo
}
Why you are using the empty method ?! Try this:
$person->family_members = $person ? FamilyMemberController::FamilyMemberOf($person->id) : null;
if($person->family_members){ // your code }
Try simple ways in Programming ;)
I want to create a json in golang for which I need to first create map of the following:
{"inputs": [{"data": {"image": {"url": "SOME_URL"}}}]}
how to create this map on golang. (for now even hardcoded will also work for me)
In a struct:
type SomeData struct {
Inputs []struct {
Data struct {
Image struct {
URL string `json:"url"`
} `json:"image"`
} `json:"data"`
} `json:"inputs"`
}
But if we wanted to be able to add things individually, AND be more idiomatic, we would do it like this:
type Image struct {
URL string `json:"url"`
}
type Data struct {
Image Image `json:"image"`
}
type Input struct {
Data Data `json:"data"`
}
type SomeData struct {
Inputs []Input `json:"inputs"`
}
Then, of course, we could always just use a map:
someData := map[interface{}]interface{}{}
It really just depends on which route you'd like to go. I suggest the second one as it gives you better fine-grained tooling without any pesky dirty tricks or code-clutter.
Hope this helps!
neededMap := make(map[string][]map[string]map[string]map[string]string)
I have a computed array which is full of tags and updates depending on what selection i make in the select box. I would like to take this array and pass it to a method and then run a method to update what “results” have an active class. Although I get an array saying I can’t run forEach on this element.
Been through a few topics and understand computed properties dont work like that but surely there is a way around this.
https://jsfiddle.net/39jb3fzw/6/
Short Snippet
methods: {
updateOutput() {
var tags = this.tagArray;
tags.forEach(function(tag) {
console.log(tag);
})
}
},
computed: {
concatenated: function () {
var ret = this.selected.concat(this.selected2, this.selected3);
this.tagArray = ret;
//this.updateOutput();
return ret;
}
}
Full Output
https://jsfiddle.net/39jb3fzw/6/
Thanks again :slight_smile:
It looks like the issue is the line:
var ret = this.selected.concat(this.selected2, this.selected3);
That line of code is returning an empty string rather than an array. This is because this.selectedX is a string rather than an Array. This explains why tag.forEach is undefined. forEach doesn't exist on the String prototype.
You can create this an array instead be doing
var ret = [ this.selected, this.selected2, this.selected3 ]
From there you can set this.tagArray to ret
Hope this helps
I created some classes with Ruby's C API. I want to create a function whose behavior will change depending on the class of the Ruby object.
I tried to use is_a? from Ruby, however, I don't think it's the good way to do this. I checked "Creating Extension Libraries for Ruby" without success. The only direct way to check classes is with the default types.
I have my class "Klass" already created:
VALUE rb_cKlass = rb_define_class("Klass", rb_cObject);
And how I wanted to check if the class is the good one:
VALUE my_function(VALUE self, VALUE my_argument) {
if(rb_check_class(my_argument), rb_cKlass)) {
// do something if my_argument is an instance of Klass
} else {
return Qnil;
}
}
Is there a way to do this?
I came across this recently, and used the RBASIC_CLASS macro, but was getting segfaults in certain scenarios for some unexplained reason.
After scanning through ruby.h, I found the CLASS_OF macro, which returns the class as VALUE of a given object.
VALUE obj = INT2NUM(10);
VALUE klass = CLASS_OF(obj); // rb_cInteger
Using Ruby 2.5
Every ruby object is internally represented by RObject struct (I will copy the source here for the sake of future readers):
struct RObject {
struct RBasic basic;
union {
struct {
uint32_t numiv;
VALUE *ivptr;
void *iv_index_tbl; /* shortcut for RCLASS_IV_INDEX_TBL(rb_obj_class(obj)) */
} heap;
VALUE ary[ROBJECT_EMBED_LEN_MAX];
} as;
};
The very first member, RBasic, defines the class:
struct RBasic {
VALUE flags;
const VALUE klass;
}
To get an access to RBasic metadata of anything, one might use RBASIC macro:
RBASIC(my_argument)
To get the class directly, one might use RBASIC_CLASS macro:
RBASIC_CLASS(my_argument)
If you want to stay close to the is_a? Ruby fashion (i.e. check if any of the ancestors is the expected class), you could directly use the C implementation of is_a?, rb_obj_is_kind_of:
rb_obj_is_kind_of(my_argument, rb_cKlass) // Qtrue OR Qfalse
And since Qfalse == 0, you can just use that method as a condition:
VALUE my_function(VALUE self, VALUE my_argument) {
if(rb_obj_is_kind_of(my_argument, rb_cKlass)) {
// do something if my_argument is an instance of Klass
} else {
return Qnil;
}
}
To find this method, just check Object#is_a? documentation and click to toggle source, you'll see the C implementation if it is a C function (hence this will work for most of the standard lib).
I'm having trouble using reflection in Go to fetch data from a cache dynamically into various statically declared struct types:
func FetchFromCacheOrSomewhereElse(cacheKey string, returnType reflect.Type) (out interface {}, err error) {
fetchFromCache := reflect.New(returnType).Interface();
_, err=memcache.Gob.Get(*context, cacheKey, &fetchFromCache);
if (err==nil) {
out=reflect.ValueOf(fetchFromCache).Elem().Interface();
} else if (err==memcache.ErrCacheMiss) {
/* Fetch data manually... */
}
return out, err;
}
It seems that reflect won't translate this statically typed cache data back into a reflect value, and returns this error instead: gob: local interface type *interface {} can only be decoded from remote interface type; received concrete type ... :\
This data is saved elsewhere in the code to the cache without the need for reflect.
memcache.Gob.Get() which is Codec.Get() expects the "target" as a pointer, wrapped into an interface{}.
Your fetchFromCache is already just that: a pointer to a value of the specified type (returnType) wrapped in an interface{}. So you don't need to take its address when passing it to Gob.Get(): pass it as-is:
_, err=memcache.Gob.Get(*context, cacheKey, fetchFromCache)