Say, we have an api which returns a list of employee records. Each record has a gender field whose value may be 'MALE' or 'FEMALE'. We want to show the gender of each employee with a message which may be 'Male' or 'Female'.
To achieve the goal above, we have following options:
Return both the value and the message so the client doesn't bother
Return the value only and let client determine the appropriate message
Which one is better?
It does depend. If you plan to give a uniform vision about your backend data and potentially there will be N API Consumer that will use your service, I'd prefer the first option. This can come in handy if you have to tackle to internationalization issue
Related
I want to retrieve highest 10 scores from firebase . When i search stackoverflow i found some answers on here Firebase retrieve highest 100 score but i can not imagine how to implement them with REST API . My code is like this. I send request to end point and get response .
RestClient.Get<User>(databaseURL + getScoreText.text + ".json").Then(response =>
{
user = response;
UpdateScore();
});
Also for 2nd way, i can get all users' info by some json parser package and parse them and get the highest scores . But if my database gets bigger , i think i ll have problems . I need a way like "orderby". Do you know any way to implement "orderby" method to my restclient code ?
Reading the firebase docs:
Filtered data is returned unordered: When using the REST API, the filtered results are returned in an undefined order since JSON interpreters don't enforce any ordering. If the order of your data is important you should sort the results in your application after they are returned from Firebase.
It seems like scaling is a real limitation of the realtime database.
Firestore can do this pretty easily if you want to switch.
If you're sticking with realtime DB, I would save a separate database-reference that only ever contains the top 10 scores.
So when a player gets a new score, they would only upload it to this reference if it's higher than the 10th top score. This would mean you would only have a DB reference containing 10 or less top scores, and scaling wouldn't be a problem. I'm not very familiar with realtime DB, but I'm sure you could write a security to rule to enforce this in a secure, server authoritative manner, at the very least a cloud function.
everyone!
I have the following situation: client sends attributes, which he wants to retrieve from table, for example "Id, Name, Price", and I should send them , having been mapped them before. The problem is, how to find out what are the types of given attribute? I want to know where the data of Price attribute is stored: val["Price"].N or val["Price"].S or somewhere else? Is there any way to find it out?
Thank you for any advice!!!
I am not familiar with the .net SDK specifically, but if you are looking for what data type each attribute is stored in DynamoDB, you could do the calls with the low level client in the SDK, as opposed to the DocumentClient. The low level client returns DynamoDB's native JSON format and will tell for each attribute if it is a string, number, map, etc.
I need to get the Marketo Leads who have changes on "progressionStatus" field (inside membership) with the API.
I can get all the leads related to a Program (with Get Leads by ProgramID API) without issues, but my need is to get those Leads with changes on "progressionStatus" column.
I was thinking to use the CreatedAt / UpdatedAt fields of the Program, so then, get all the leads related to those programs. But I didn't get the accurate results that I want.
Also, I tried to use the GET Lead changes API and use "fields" parameter to "progressionstatus" but that field don't exist.
It is possible to resolve this?
Thanks in advance.
You can get the list of Leads with progression status change by querying against the Get Lead Activities endpoint.
The Get Lead Changes endpoint could sound as a good candidate, but that endpoint only returns changes on the lead fields. Progression status change is not stored on the lead directly, so at the end that won't work. On the other hand the Get Leads by ProgramId endpoint returns –amongst others– the actual value of progressionStatus (program status of the lead in the parent program) but not the “change” itself, so you cannot process the resultset based on that.
The good news is that the progression status change is an activity type and luckily we have the above mentioned Get Lead Activities endpoint (which is also mentioned as the Query in the API docs) available to query just that. This endpoint also allows for filtering by activityTypeIds to narrow down the resultset to a single activity type.
Basically you have to call the GET /rest/v1/activities.json enpoint and pass the values of activityTypeIds and nextPageToken as query parameters (next to the access token obviously). So, first you need to get the internal Id of the activity type called “Change Status in Progression”. You can do that by querying the GET /rest/v1/activities/types.json endpoint and look for a record with that name. (I don't know if this Id changes from instance to instance, but in ours it is the #104). Also, to obtain a nextPageToken you have to make a call to GET /rest/v1/activities/pagingtoken.json as well, where you have to specify the earliest datetime to retrieve activities from. See more about Paging Tokens.
Once you have all of these bits at hand, you can make your request like that:
GET https://<INSTANCE_ID>.mktorest.com/rest/v1/activities.json?activityTypeIds=<TYPE_ID>&nextPageToken=<NEXTPAGE_TOKEN>&access_token=<ACCESS_TOKEN>
The result it gives is an array with items like below, which is easy to process further.
{
"id":712630,
"marketoGUID":"712630",
"leadId":824864,
"activityDate":"2017-12-01T08:51:13Z",
"activityTypeId":104,
"primaryAttributeValueId":1104,
"primaryAttributeValue":"PROGRAM_NAME",
"attributes":[
{"name":"Acquired By","value":true},
{"name":"New Status ID","value":33},
{"name":"Old Status ID","value":32},
{"name":"Reason","value":"Filled out form"},
{"name":"Success","value":false},
{"name":"New Status","value":"Filled-out Form"},
{"name":"Old Status","value":"Not in Program"}
]
}
Knowing the leadIds in question, you can make yet another request to fetch the actual lead records.
I'm designing a chat app much like Facebook Messenger. My two current root nodes are chats and users. A user has an associated list of chats users/user/chats, and the chats are added by autoID in the chats node chats/a151jl1j6. That node stores information such as a list of the messages, time of the last message, if someone is typing, etc.
What I'm struggling with is where to make the definition of which two users are in the chat. Originally, I put a reference to the other user as the value of the chatId key in the users/user/chats node, but I thought that was a bad idea incase I ever wanted group chats.
What seems more logical is to have a chats/chat/members node in which I define userId: true, user2id: true. My issue with this is how to efficiently query it. For example, if the user is going to create a new chat with a user, we want to check if a chat already exists between them. I'm not sure how to do the query of "Find chat where members contains currentUserId and friendUserId" or if this is an efficient denormalized way of doing things.
Any hints?
Although the idea of having ids in the format id1---||---id2 definitely gets the job done, it may not scale if you expect to have large groups and you have to account for id2---||---id1 comparisons which also gets more complicated when you have more people in a conversation. You should go with that if you don't need to worry about large groups.
I'd actually go with using the autoId chats/a151jl1j6 since you get it for free. The recommended way to structure the data is to make the autoId the key in the other nodes with related child objects. So chats/a151jl1j6 would contain the conversation metadata, members/a151jl1j6 would contain the members in that conversation, messages/a151jl1j6 would contain the messages and so on.
"chats":{
"a151jl1j6":{}}
"members":{
"a151jl1j6":{
"user1": true,
"user2": true
}
}
"messages":{
"a151jl1j6":{}}
The part where this gets is little "inefficient" is the querying for conversations that include both user1 and user2. The recommended way is to create an index of conversations for each user and then query the members data.
"user1":{
"chats":{
"a151jl1j6":true
}
}
This is a trade-off when it comes to querying relationships with a flattened data structure. The queries are fast since you are only dealing with a subset of the data, but you end up with a lot of duplicate data that need to be accounted for when you are modifying/deleting i.e. when the user leaves the chat conversation, you have to update multiple structures.
Reference: https://firebase.google.com/docs/database/ios/structure-data#flatten_data_structures
I remember I had similar issue some time ago. The way how I solved it:
user 1 has an unique ID id1
user 2 has an unique ID id2
Instead of adding a new chat by autoId chats/a151jl1j6 the ID of the chat was id1---||---id2 (superoriginal human-readable delimeter)
(which is exactly what you've originally suggested)
Originally, I put a reference to the other user as the value of the chatId key in the users/user/chats node, but I thought that was a bad idea in case I ever wanted group chats.
There is a saying: https://en.wikipedia.org/wiki/You_aren%27t_gonna_need_it
There might a limitation of how many userIDs can live in the path - you can always hash the value...
My question is a really basic question. Consider to query a modality work list to get some work items by a C-FIND query. Consider using a sequence (SQ) as Return Key attribute for the C-FIND query, for example: [0040,0100] (Scheduled Procedure Step) and universal matching.
What should I expect in the SCP's C-FIND response? Or, better say, what should I expect to find with regards of the scheduled procedure step for a specific work item? All the mandatory items that Modality Work List Information Model declare as encapsulated in the sequence? Should I instead explicitly issue a C-FIND request for those keys I want the SCP return in the response?
For example: if I want the SCP return the Scheduled Procedure Step Start Time and Scheduled Procedure Start Date, do I need to issue a specific C-FIND request with those keys or querying for Scheduled Procedure Step key is enough to force the SCP to send all items related to the Scheduled Procedure Step itself?
Yes, you should include the Scheduled Procedure Step Start Time / Date Tags into the 0040,0100 sequence.
See also Service Class Specifications (K6.1.2.2)
This will not ensure you will retrieve this information, because it depends on the Modality Worklist Provider, which information will be returned.
You could also request a Dicom Conformance Statement from the Modality Provider to know the necessary tags for request/retrieve.
As for table K.6-1, you can consider it as showing only the requirement of the SCP side or what SCP is required to use for matching key (i.e. query filter) and additional required attribute values to return (i.e. Return Key) with successful match. It is up to SCP’s implementation to support matching against required key but you can always expect SCP to use the values in matching key for query filter.
Also note that, SCP is only required to return values for attributes that are present in the C-FIND Request. One exception is the sequence matching and there you have the universal matching like mechanism where you can pass a zero length ITEM to retrieve entire sequence. So as stated in PS 3.4 section C.2.2.2.6, you can just include an empty ITEM (FFFE, E000) element with VR of SQ under Scheduled Procedure Step Sequence (0040, 0100) for universal matching.