I have been researching Firebase as an alternative to the recently deprecated Dropbox Datastore API. I read the articles about structuring data, but I’m still a little unclear.
I have a bunch of users:
users
- name
- email
...and each user has three database “tables”, aircraft, entries, and customFields.
aircraft
- name
- category
- make
entries
- flightDate
- departure
- destination
customFields
- name
- type
So would my Firebase data structure look something like this?
{
“users”: {
“bob”: {
“name”: …
“email”: …
},
“sally”: {
“name”: …
“email”: …
}
},
“aircraft”:{
???
},
“entries”:{
???
},
“customFields”:{
???
}
}
Thanks in advance.
Are you familiar with OOP? Each "table" is an object. Personally I would do something as follows. Since I don't understand what you're trying to achieve with the database and their objects, this may not be correct:
{
"user": {
"name": "bob",
"aircraft": {
"name": "name"
},
"entries": {
"flightdate": "27/05/2015"
}
}
}
Think in objects, not tables. Think parent and child.
But in your example, if each object (user, aircraft, entries etc.) was plurals, you can treat them as a "table", it would just be an array of objects:
{
"aircrafts":[
{
"id":1,
"name": "name"
},
{
"id":2,
"name": "name"
}
]
}
Edit: My first example was if each user had an aircraft, in retrospect it was silly, but my point still stands.
Related
I would like to add to add a custom extension to my Schedule resource.
In my app, Schedule have visit motives (reasons). I know there's a list of classified appointments / encounter reasons but I would like to use mine.
I have something like this :
{
"resourceType":"Schedule",
"identifier":"logical_id",
"type":"schedule_speciality",
"actor":{
"practioner_id":"identifier",
"practioner_name":"practioner name"
},
"external_id":{
"extension":[
{
"url":"http://api.test.com/fhir/schedule/external_id",
"valueIdentifier":"external_id"
}
]
},
"visit_motives":{
"extension":[
{
"url":"https://api.test.com/fhir/ValueSet/schedule#visit_motives",
"valueString":"vist_motive1"
},
{
"url":"https://api.test.com/fhir/ValueSet/schedule#visit_motives",
"valueString":"vist_motive2"
},
{
"url":"https://api.test.com/fhir/ValueSet/schedule#visit_motives",
"valueString":"vist_motive3"
}
]
},
"practice_id":{
"extension":[
{
"url":"https://api.test.com/fhir/schedule/practice_id",
"valueIdentifier":"practice_id"
}
]
}
}
I'm not sure about this part :
"visit_motives":{
"extension":[
{
"url":"https://api.test.com/fhir/ValueSet/schedule#visit_motives",
"valueString":"vist_motive1"
},
{
"url":"https://api.test.com/fhir/ValueSet/schedule#visit_motives",
"valueString":"vist_motive2"
},
{
"url":"https://api.test.com/fhir/ValueSet/schedule#visit_motives",
"valueString":"vist_motive3"
}
]
}
Is it correct to add an extension this way ? There are always multiple visit motives for a specific schedule so I have to list them.
I also have seen this kind of things :
"visit_motives": {
"coding": [
{
"system": "https://api.test.com/fhir/ValueSet/schedule#visit_motives",
"code": "visit_motive1"
}
]
}
Which one is the correct one or am I wrong ?
There are several issues here:
It seems odd to capture a "reason" on a schedule. A schedule says when a particular clinician or clinic or other resource is available. E.g. "Dr. Smith takes appointments Mon/Wed/Fri from 1pm-4pm". So if you were to capture a reason on the resource, it would reflect "Why does Dr. Smith have a schedule?" Typically reasons are captured for an individual Appointment. That's the resource that reserves a particular slot for a planned visit. And Appointment already has an element for reason where you're free to use your own codes or just send text.
You have extensions to convey identifiers, but Schedule already has an element for identifiers. Why would you use extensions instead of the standard element? Note that you can use the "system" and/or "type" components to differentiate different kinds of identifiers.
You're sending "identifier", "type", "name", etc. as simple strings - but they're complex data types, so you need to communicate the child elements
actor is of type Reference - that means you need to point to the Practitioner resource. You can't send the properties in-line. (If the Practitioner only exists in the context of the Schedule, you could use the "contained" approach which would use an internal reference, but containment doesn't seem to make sense in this use-case.
The URL for your extension contains ValueSet, which isn't correct - extensions are all structure definitions. Also, there shouldn't be a # symbol in the URL.
Your syntax for extensions is incorrect. You can't introduce new properties in FHIR. The property name for all extensions is just "extension". You differentiate by the URL. So your syntax should be:
{
"resourceType":"Schedule",
"id":"logical_id",
"extension": [
{
"url":"https://api.test.com/fhir/StructureDefinition/schedule-visit_motive",
"valueString":"vist_motive1"
},
{
"url":"https://api.test.com/fhir/StructureDefinition/schedule-visit_motive",
"valueString":"vist_motive2"
},
{
"url":"https://api.test.com/fhir/StructureDefinition/schedule-visit_motives",
"valueString":"vist_motive3"
}
],
"identifier": [
{
"system": http://api.test.com/fhir/NamingSystem/external_id",
"value": "external_id"
}
{
"system": http://api.test.com/fhir/NamingSystem/practice_id",
"value": "practice_id"
}
]
"type": {
"coding": {
"system": "http://somewhere.org/fhir/CodeSystem/specialties",
"code": "schedule_speciality"
},
"text": "Some text description of specialty"
},
"actor":{
"reference": "http://myserver.org/fhir/Practitioner/12345"
"display": "Dr. smith"
}
}
The following is my structure of data
[
{
"id": 1,
"title": "Welcome to my playground",
"description": "This is so fun to play with, you will like it <3",
"comments": [
{
"id": 1140406,
"comment": "this is an example comment",
"postId": 1
}
]
},
...
]
And I'm trying to use immutable js to do this operation
Get all the posts
Search for a post I want to add comment to
Adding the comments when the post is found
The following is my code
posts = posts.map((post) => {
if(post.get('id') == payload.post_id) {
return post.update('comments', (comments) => {
return comments.push(Map({
id: payload.id,
comment: payload.comment
}));
});
}
return post;
});
But I assume this pattern is very common and there should be a simpler way to do this in immutableJS. Any advice will be helpful, thanks.
First off, it's worth mentioning that your Data structure is Immutable Lists and Maps.. not JS Arrays and Objects.
OK, without changing your data structure you could do:
posts.map(post => post.get('id') === payload.post_id ?
post.update('comments', comments.push(payload) :
post)
If you were to change your data structure, and instead of having a List of posts, had a Map of post's with their ID as the key you could just do:
post.updateIn([payload.post_id, 'comments'], comments => comments.push(payload))
BTW you can use push or concat here, both will function the same.
Also, if comments may be undefined, you can provide a "noSetValue" as a List (https://facebook.github.io/immutable-js/docs/#/List/updateIn):
posts.map(post => post.get('id') === payload.post_id ?
post.update('comments', Immutable.List([]), comments.push(payload) :
post)
post.updateIn([payload.post_id, 'comments'], Immutable.List([]), comments => comments.push(payload))
For others who has the same question: One should consider a data normalisation (search for normalizr). You could then normalise your data to something like:
"entities": {
"posts": {
"1": {
"id": 1,
"title": "Welcome to my playground",
"description": "This is so fun to play with, you will like it <3",
"comments": [1140406, 1140407, 1140408]
},
"42" : {...}
}
"comments": {
"1140406": {
"id": 1140406,
"comment": "this is an example comment",
"postId": 1
},
"1140407": {...}
}
}
then updating post and comments becomes much easier
I was just looking in the docs but couldn't find anything.
So my web app has a structure that's similar to the one in this site.
For the sake of simplicity, let's say my app has only questions which are catalogued by tags. As suggested in the docs, we store our data with a flat, non-normalized structure (E.g.
{
"questions": {
...
},
"tags": {
"tag1": {
"name": "Tag1",
"questions": { "0": true, "1": true }
},
"tag2": {
"name": "Tag2",
"questions": { "2": true, "3": true }
}
}
}
), rather than a normalized structure without data replication like:
{
"questions": {
"0": { "title": ..., "tag": ... },
"1": { "title": ..., "tag": ... },
}
}
One of the advantages of using the first structure is that I can search for questions that have a certain tag without downloading all the data of all of the questions first: querying for /tags/tag1/questions, will return all the object with all of the question's keys. Now, I can query for the questions, but how do I do that?
I don't want to make ten requests for every question, it seems a waste of time and performance, but I couldn't find a way to make Firebase filter by multiple keys. It seems I can only give Firebase one input at a time. I think (and I hope) I am missing something here. What is it?
If I really can't do this, how do I search by tags here?
I'm using JMSSerializer and FOSRestBundle. I have a fairly typical object graph, including some recursion.
What I would like to accomplish is that included objects beyond a certain depth or in general are listed only with their ID, but when serialized directly, with all data.
So, for example:
Users => Groups => Users
when requesting /user/1 the result should be something like
{ "id": 1, "name": "John Doe", "groups": [ { "id": 10 }, { "id": 11 } ] }
While when I request /group/10 it would be:
{ "id": 10, "name": "Groupies", "users": [ { "id": 1 }, { "id": 2 }, { "id": 4 } ] }
With #MaxDeph I can hide the included arrays completely, so I get
{ "id": 1, "name": "John Doe", "groups": [] }
But I would like to include just the IDs so that the REST client can fetch them if it needs them, or consult his cache, or do whatever.
I know I can manually cobble this together using groups, but for consistency reasons I was wondering if I can somehow enable this behaviour in my entire application, maybe even with a reference to maxdepth so I can control where to include IDs and where to include full objects?
For the sake of those finding this:
I found no other solution, but doing this with groups works just fine and gives me the result I was looking for.
** UPDATE **
Thanks to Alfred Fuller for pointing out that I need to create a manual index for this query.
Unfortunately, using the JSON API, from a .NET application, there does not appear to be an officially supported way of doing so. In fact, there does not officially appear to be a way to do this at all from an app outside of App Engine, which is strange since the Cloud Datastore API was designed to allow access to the Datastore outside of App Engine.
The closest hack I could find was to POST the index definition using RPC to http://appengine.google.com/api/datastore/index/add. Can someone give me the raw spec for how to do this exactly (i.e. URL parameters, what exactly should the body look like, etc), perhaps using Fiddler to inspect the call made by appcfg.cmd?
** ORIGINAL QUESTION **
According to the docs, "a query can combine equality (EQUAL) filters for different properties, along with one or more inequality filters on a single property".
However, this query fails:
{
"query": {
"kinds": [
{
"name": "CodeProse.Pogo.Tests.TestPerson"
}
],
"filter": {
"compositeFilter": {
"operator": "and",
"filters": [
{
"propertyFilter": {
"operator": "equal",
"property": {
"name": "DepartmentCode"
},
"value": {
"integerValue": "123"
}
}
},
{
"propertyFilter": {
"operator": "greaterThan",
"property": {
"name": "HourlyRate"
},
"value": {
"doubleValue": 50
}
}
},
{
"propertyFilter": {
"operator": "lessThan",
"property": {
"name": "HourlyRate"
},
"value": {
"doubleValue": 100
}
}
}
]
}
}
}
}
with the following response:
{
"error": {
"errors": [
{
"domain": "global",
"reason": "FAILED_PRECONDITION",
"message": "no matching index found.",
"locationType": "header",
"location": "If-Match"
}
],
"code": 412,
"message": "no matching index found."
}
}
The JSON API does not yet support local index generation, but we've documented a process that you can follow to generate the xml definition of the index at https://developers.google.com/datastore/docs/tools/indexconfig#Datastore_Manual_index_configuration
Please give this a shot and let us know if it doesn't work.
This is a temporary solution that we hope to replace with automatic local index generation as soon as we can.
The error "no matching index found." indicates that an index needs to be added for the query to work. See the auto index generation documentation.
In this case you need an index with the properties DepartmentCode and HourlyRate (in that order).
For gcloud-node I fixed it with those 3 links:
https://github.com/GoogleCloudPlatform/gcloud-node/issues/369
https://github.com/GoogleCloudPlatform/gcloud-node/blob/master/system-test/data/index.yaml
and most important link:
https://cloud.google.com/appengine/docs/python/config/indexconfig#Python_About_index_yaml to write your index.yaml file
As explained in the last link, an index is what allows complex queries to run faster by storing the result set of the queries in an index. When you get no matching index found it means that you tried to run a complex query involving order or filter. So to make your query work, you need to create your index on the google datastore indexes by creating a config file manually to define your indexes that represent the query you are trying to run. Here is how you fix:
create an index.yaml file in a folder named for example indexes in your app directory by following the directives for the python conf file: https://cloud.google.com/appengine/docs/python/config/indexconfig#Python_About_index_yaml or get inspiration from the gcloud-node tests in https://github.com/GoogleCloudPlatform/gcloud-node/blob/master/system-test/data/index.yaml
create the indexes from the config file with this command:
gcloud preview datastore create-indexes indexes/index.yaml
see https://cloud.google.com/sdk/gcloud/reference/preview/datastore/create-indexes
wait for the indexes to serve on your developer console in Cloud Datastore/Indexes, the interface should display "serving" once the index is built
once it is serving your query should work
For example for this query:
var q = ds.createQuery('project')
.filter('tags =', category)
.order('-date');
index.yaml looks like:
indexes:
- kind: project
ancestor: no
properties:
- name: tags
- name: date
direction: desc
Try not to order the result. After removing orderby(), it worked for me.