Piotr Walczak :
{
"groups": [
{
"name": "Event",
"groups": [
{
"name": "Service",
"subscriptions": [
{
"topic": "SERVICE_STATUS_PRESETS"
},
{
"topic": "AIRCRAFT_ACTIVATION",
},
{
"topic": "OUT_OF_SERVICE",
}
]
}
]
},
{
"name": "Enquiries",
"groups": [
{
"name": "Service-related",
"subscriptions": [
{
"topic": "PROMO_CODES_REQUESTS",
}
]
}
]
}
],
"subscriptions": [
{
"topic": "BANNERS",
},
{
"topic": "DOCUMENTS",
},
{
"topic": "USER",
}
]
}
OK guys I have such JSON structure what I need is to: return all topics in array, in this example it will be:
["SERVICE_STATUS_PRESETS", "AIRCRAFT_ACTIVATION", "OUT_OF_SERVICE", "PROMO_CODES_REQUESTS", "BANNERS", "DOCUMENTS", "USER"]
I try recursive calls like this, though I only get last three records:
getRecursive() {
if (Array.isArray(data)) {
for (let i = 0; i < data.length; i++) {
if (data[i].subscriptions) {
return data[i].subscriptions.map((val: SubscriptionGroupDetails) => val.topic);
} else if (data[i].groups) {
return this.getAllTopics(data[i].groups);
}
}
}
if (data && data.groups) {
return this.getAllTopics(data.groups);
}
return data.subscriptions.map((val: SubscriptionGroupDetails) => val.topic);
}
Nina Scholz :
You could take a recursive approach and check
- if the handed over data is not an object for checking, then return with empty array,
- if the object has the wanted property, then return an array with the value of
topic
, - or get the values and make a recursive call with the function and return an array with the result of it.
function getTopics(object) {
if (!object || typeof object !== 'object') return [];
if ('topic' in object) return [object.topic];
return Object.values(object).reduce((r, v) => [...r, ...getTopics(v)], []);
}
var data = { groups: [{ name: "Event", groups: [{ name: "Service", subscriptions: [{ topic: "SERVICE_STATUS_PRESETS" }, { topic: "AIRCRAFT_ACTIVATION" }, { topic: "OUT_OF_SERVICE" }] }] }, { name: "Enquiries", groups: [{ name: "Service-related", subscriptions: [{ topic: "PROMO_CODES_REQUESTS" }] }] }], subscriptions: [{ topic: "BANNERS" }, { topic: "DOCUMENTS" }, { topic: "USER" }] },
result = getTopics(data);
console.log(result);