How to get current line on change in slate.js - slate.js

How does one get the current line, or the currently edited node, within the onChange or onKeyDown methods in Slate.js?
I'm trying to add an updatedAt or createdAt parameter in the data attribute for a particular line.
Here's a proof of concept for what I'm trying to do:
onChange = ({ value }) => {
return value.document.nodes.reduce((change, node) => {
return change.setNodeByKey(node.get("key"), {
data: {
createdAt: new Date(),
...node.get("data").toJS(),
},
});
}, value.change()).value;
}
This loops through every node and adds a createdAt attribute in data if one is not already present. This is obviously not great code since it's looping through every node and has to unserialize the Immutable data object for each node, but it hopefully illustrates what I'm looking to do.
How do I set the data attribute for just the current node?

A few things I've learned:
anchorkey gets you the current key of the selection
Value has a useful shortcut, startKey
Using the currently selected key, you can then loop through the nodes on a document to get the current node.
I'm not sure if Slatejs provides a way to grab a node by key; if so I can't find it, but the above gets me to where I want.

Related

Apollo duplicates first result to every node in array of edges

I am working on a react app with react-apollo
calling data through graphql when I check in browser network tab response it shows all elements of the array different
but what I get or console.log() in my app then all elements of array same as the first element.
I don't know how to fix please help
The reason this happens is because the items in your array get "normalized" to the same values in the Apollo cache. AKA, they look the same to Apollo. This usually happens because they share the same Symbol(id).
If you print out your Apollo response object, you'll notice that each of the objects have Symbol(id) which is used by Apollo cache. Your array items probably have the same Symbol(id) which causes them to repeat. Why does this happen?
By default, Apollo cache runs this function for normalization.
export function defaultDataIdFromObject(result: any): string | null {
if (result.__typename) {
if (result.id !== undefined) {
return `${result.__typename}:${result.id}`;
}
if (result._id !== undefined) {
return `${result.__typename}:${result._id}`;
}
}
return null;
}
Your array item properties cause multiple items to return the same data id. In my case, multiple items had _id = null which caused all of these items to be repeated. When this function returns null the docs say
InMemoryCache will fall back to the path to the object in the query,
such as ROOT_QUERY.allPeople.0 for the first record returned on the
allPeople root query.
This is the behavior we actually want when our array items don't work well with defaultDataIdFromObject.
Therefore the solution is to manually configure these unique identifiers with the dataIdFromObject option passed to the InMemoryCache constructor within your ApolloClient. The following worked for me as all my objects use _id and had __typename.
const client = new ApolloClient({
link: authLink.concat(httpLink),
cache: new InMemoryCache({
dataIdFromObject: o => (o._id ? `${o.__typename}:${o._id}`: null),
})
});
Put this in your App.js
cache: new InMemoryCache({
dataIdFromObject: o => o.id ? `${o.__typename}-${o.id}` : `${o.__typename}-${o.cursor}`,
})
I believe the approach in other two answers should be avoided in favor of following approach:
Actually it is quite simple. To understand how it works simply log obj as follows:
dataIdFromObject: (obj) => {
let id = defaultDataIdFromObject(obj);
console.log('defaultDataIdFromObject OBJ ID', obj, id);
}
You will see that id will be null in your logs if you have this problem.
Pay attention to logged 'obj'. It will be printed for every object returned.
These objects are the ones from which Apollo tries to get unique id ( you have to tell to Apollo which field in your object is unique for each object in your array of 'items' returned from GraphQL - the same way you pass unique value for 'key' in React when you use 'map' or other iterations when rendering DOM elements).
From Apollo dox:
By default, InMemoryCache will attempt to use the commonly found
primary keys of id and _id for the unique identifier if they exist
along with __typename on an object.
So look at logged 'obj' used by 'defaultDataIdFromObject ' - if you don't see 'id' or '_id' then you should provide the field in your object that is unique for each object.
I changed example from Apollo dox to cover three cases when you may have provided incorrect identifiers - it is for cases when you have more than one GraphQL types:
dataIdFromObject: (obj) => {
let id = defaultDataIdFromObject(obj);
console.log('defaultDataIdFromObject OBJ ID', obj, id);
if (!id) {
const { __typename: typename } = obj;
switch (typename) {
case 'Blog': {
// if you are using other than 'id' and '_id' - 'blogId' in this case
const undef = `${typename}:${obj.id}`;
const defined = `${typename}:${obj.blogId}`;
console.log('in Blogs -', undef, defined);
return `${typename}:${obj.blogId}`; // return 'blogId' as it is a unique
//identifier. Using any other identifier will lead to above defined problem.
}
case 'Post': {
// if you are using hash key and sort key then hash key is not unique.
// If you do query in DB it will always be the same.
// If you do scan in DB quite often it will be the same value.
// So use both hash key and sort key instead to avoid the problem.
// Using both ensures ID used by Apollo is always unique.
// If for post you are using hashKey of blogID and sortKey of postId
const notUniq = `${typename}:${obj.blogId}`;
const notUniq2 = `${typename}:${obj.postId}`;
const uniq = `${typename}:${obj.blogId}${obj.postId}`;
console.log('in Post -', notUniq, notUniq2, uniq);
return `${typename}:${obj.blogId}${obj.postId}`;
}
case 'Comment': {
// lets assume 'comment's identifier is 'id'
// but you dont use it in your app and do not fetch from GraphQl, that is
// you omitted 'id' in your GraphQL query definition.
const undefnd = `${typename}:${obj.id}`;
console.log('in Comment -', undefnd);
// log result - null
// to fix it simply add 'id' in your GraphQL definition.
return `${typename}:${obj.id}`;
}
default: {
console.log('one falling to default-not good-define this in separate Case', ${typename});
return id;
}
I hope now you see that the approach in other two answers are risky.
YOU ALWAYS HAVE UNIQUE IDENTIFIER. SIMPLY HELP APOLLO BY LETTING KNOW WHICH FIELD IN OBJECT IT IS. If it is not fetched by adding in query definition add it.
An alternative option to the accepted is to instead of dataIdFromObject, which appears to be for everything in the query, I was able to provide a keyFields function per type that required it.
const client = new ApolloClient({
cache: new InMemoryCache({
typePolicies: {
ItemType: {
keyFields: (obj) =>
obj.id + "-" + obj.language.id,
},
},
}),
});
In the above example ItemType can be whichever Type is specified in your schema. I happened to be joining a non-unique ID with a language to make a unique key but you can do it however you wish.

Identifying targetList in ember-drag-sort

I am currently trying to implement an ember-drag-sort nested list into my Ember.js app.
Is there a way to determine in the dragEnd action which "sub-list" the item has been dropped into? (e.g. a class name, id etc)
In my scenario, I am sorting ember data records that can belong to each other (i.e. a nested, 'tree' structure). When I drag one nested record "into" another (making the dragged record a child of the second record), I need to update the parent attribute in ember-data. My question is, how do you pass some id of the second record (the new parent) to the dragEnd action?
Is this even possible?
EDIT:
To put it another way, I want to be able to identify which list I have dropped the item into.
targetList refers to the array on the dragged side of the component. For pushing the parent to the target list alongside the child, you can take a look at this twiddle.
To simplify identification of lists, the additional arguments feature has been implemented by #rwwagner90 (SO, GitHub).
You can pass some kind of list identifier into the additionalArgs argument to your lists. In this example I'm passing parent records which own the lists:
{{#each parents as |parent|}}
{{#drag-sort-list
items = parent.children
additionalArgs = (hash parent=parent)
dragEndAction = (action 'dragEnd')
as |child|
}}
{{child.name}}
{{/drag-sort-list}}
{{/each}}
In the dragEnd action you can access the parent records that own the source list and the target list:
dragEndAction({ sourceList, sourceIndex, sourceArgs, targetList, targetIndex, targetArgs }) {
if (sourceModel === targetModel && sourceIndex === targetIndex) return;
const item = sourceList.objectAt(sourceIndex);
sourceList.removeAt(sourceIndex);
targetList.insertAt(targetIndex, item);
// Access the parent via `sourceArgs` and `targetArgs`
sourceArgs.parent.save();
targetArgs.parent.save();
}

How to get from CouchDB only certain fields of certain documents with a single request?

create a view that return only a subset of values from a document, each with its key and value within a json string. like if one given view returns a document as this following, Is it possible to get some fields information for a one request? thank you
{
"total_rows":10,
"offset":3,
"rows":[{
"id":"doc1",
"key":"abc123",
"value": {
"_id":"aaaa",
"_rev":"bbb",
"field1":"abc",
"field2":"bcd",
"field3":"cde",
"field4":"123",
"field5":"789",
"field6":"aa#email.com",
"field7":"ttt",
"field8":"iii",
"field9":[{
"field91":"tyui",
"field92":"55555"
}],
"field10"::"0000",
"field11"::"55555",
"field12"::"0030".........
}
}
I just want to create a view that returns some fields only the following:
{
"field1":"abc",
"field2":"bcd",
"field3":"cde",
"field4":"123",
"field5":"789",
"field6":"aa#email.com",
"field7":"ttt",
"field8":"iii",
"field9":[{
"field91":"tyui",
"field92":"55555"
}]
}
A map function that emits a new document with selected fields only. As an example, let's map field1 (a string) and field9 (an array) only:
function map(doc) {
emit(doc._id, {
field1: doc.field1,
field9: doc.field9
});
}
In the above example, each document will be fired with a key being the original doc ID and the value being the mapped fields you require.
This is useful if you are planning to add a reduce function later.
Depending on your use case, you may just want to emit the mapped objects:
function map(doc) {
emit({
field1: doc.field1,
field9: doc.field9
});
}
Please see http://guide.couchdb.org/draft/views.html
The documentation on building data views is pretty good, you can discover a lot by experimenting..

record not added to model when i call save() on a new record in Ember-Data

Using Ember-Data 0.13-59 & Ember 1.0.0 RC 6 (from starter kit)
Problem: upon save() to a new record made from App.Userstat.createRecord({ ... }) the server gets the POST and successfully returns an id but the new record is not available in the Userstat model.
To better understand example: this is a quiz app(for multiple choice questions). Each question has several choices and when a user selects a choice, their choice to the corresponding question is stored in a Model, App.Userstat.
At each question, the app needs to know whether the user has already answered this question or if it's new.
I use a computed property as a setter and getter. The setter is called when a user selects a choice (the choice's value is passed to computed property). First it checks if a record exists for the user's current question. If it doesn't exist it will create a new record. If it does exist, it should only issue a PUT request with updated content.
Code Updated(July 8, 11AM)
App.UserstatsController = Ember.ArrayController.extend();
App.QuestionController = Ember.ObjectController.extend({
needs: "userstats",
chosen = function(key, value) {
// getter
if(value === undefined) {
// something goes here
// setter
} else {
// the question.id is used to compare for an existing record in Userstat mdoel
var questionId = this.get('id');
var questionModel = this.get('model');
// does any Userstat record belong to the current question??
var stats = this.get('controllers.Userstats');
var stat = stats.get('model').findProperty('question.id', questionId);
// if no record exists for stat, means user has not answered this question yet...
if(!stat) {
newStat = App.Userstat.createRecord({
"question" : questionModel,
"choice" : value // value passed to the computed property
)}
newStat.save(); // I've tried this
// newStat.get('store').commit(); // and this
return value;
// if there is a record(stat) then we will just update the user's choice
} else {
stat.set('choice', value);
stat.get('store').commit();
return value;
}
}.property('controllers.Userstats')
No matter how many times I set chosen it always sends a POST (as opposed to an update only sending a PUT request) because it never adds the record to the model the first time.
To demonstrate further, in the setter part of the computed property, when I put this code:
var stats = this.get('controllers.Userstats')
console.log stats
the Userstats controller shows all previously existing records, but not newly submitted records!
How come the new record isn't available after I save() or commit() it???
Thanks :)
EDIT
maybe it has something to do with me adding a record to the singular model App.Userstat and then when I look for it, I'm searching using the UserstatsController which is an Array controller???
I don't know if it's a typo, but the computed property is defined the wrong way and should be like this:
App.QuestionController = Ember.ObjectController.extend({
needs: 'userstats',
choice: 'controllers.userstats.choice',
chosen: function(key, value) {
...
}.property('choice')
...
});
Inside the property() you should also define properties that trigger the computed property if they change. This way if choice changes the chosen cp will be triggered.
Please let me know if it helps.

Adding item to filtered result from ember-data

I have a DS.Store which uses the DS.RESTAdapter and a ChatMessage object defined as such:
App.ChatMessage = DS.Model.extend({
contents: DS.attr('string'),
roomId: DS.attr('string')
});
Note that a chat message exists in a room (not shown for simplicity), so in my chat messages controller (which extends Ember.ArrayController) I only want to load messages for the room the user is currently in:
loadMessages: function(){
var room_id = App.getPath("current_room.id");
this.set("content", App.store.find(App.ChatMessage, {room_id: room_id});
}
This sets the content to a DS.AdapterPopulatedModelArray and my view happily displays all the returned chat messages in an {{#each}} block.
Now it comes to adding a new message, I have the following in the same controller:
postMessage: function(contents) {
var room_id = App.getPath("current_room.id");
App.store.createRecord(App.ChatMessage, {
contents: contents,
room_id: room_id
});
App.store.commit();
}
This initiates an ajax request to save the message on the server, all good so far, but it doesn't update the view. This pretty much makes sense as it's a filtered result and if I remove the room_id filter on App.store.find then it updates as expected.
Trying this.pushObject(message) with the message record returned from App.store.createRecord raises an error.
How do I manually add the item to the results? There doesn't seem to be a way as far as I can tell as both DS.AdapterPopulatedModelArray and DS.FilteredModelArray are immutable.
so couple of thoughts:
(reference: https://github.com/emberjs/data/issues/190)
how to listen for new records in the datastore
a normal Model.find()/findQuery() will return you an AdapterPopulatedModelArray, but that array will stand on its own... it wont know that anything new has been loaded into the database
a Model.find() with no params (or store.findAll()) will return you ALL records a FilteredModelArray, and ember-data will "register" it into a list, and any new records loaded into the database will be added to this array.
calling Model.filter(func) will give you back a FilteredModelArray, which is also registered with the store... and any new records in the store will cause ember-data to "updateModelArrays", meaning it will call your filter function with the new record, and if you return true, then it will stick it into your existing array.
SO WHAT I ENDED UP DOING: was immediately after creating the store, I call store.findAll(), which gives me back an array of all models for a type... and I attach that to the store... then anywhere else in the code, I can addArrayObservers to those lists.. something like:
App.MyModel = DS.Model.extend()
App.store = DS.Store.create()
App.store.allMyModels = App.store.findAll(App.MyModel)
//some other place in the app... a list controller perhaps
App.store.allMyModels.addArrayObserver({
arrayWillChange: function(arr, start, removeCount, addCount) {}
arrayDidChange: function(arr, start, removeCount, addCount) {}
})
how to push a model into one of those "immutable" arrays:
First to note: all Ember-Data Model instances (records) have a clientId property... which is a unique integer that identifies the model in the datastore cache whether or not it has a real server-id yet (example: right after doing a Model.createRecord).
so the AdapterPopulatedModelArray itself has a "content" property... which is an array of these clientId's... and when you iterate over the AdapterPopulatedModelArray, the iterator loops over these clientId's and hands you back the full model instances (records) that map to each clientId.
SO WHAT I HAVE DONE
(this doesn't mean it's "right"!) is to watch those findAll arrays, and push new clientId's into the content property of the AdapterPopulatedModelArray... SOMETHING LIKE:
arrayDidChange:function(arr, start, removeCount, addCount){
if (addCount == 0) {return;} //only care about adds right now... not removes...
arr.slice(start, start+addCount).forEach(function(item) {
//push clientId of this item into AdapterPopulatedModelArray content list
self.getPath('list.content').pushObject(item.get('clientId'));
});
}
what I can say is: "its working for me" :) will it break on the next ember-data update? totally possible
For those still struggling with this, you can get yourself a dynamic DS.FilteredArray instead of a static DS.AdapterPopulatedRecordArray by using the store.filter method. It takes 3 parameters: type, query and finally a filter callback.
loadMessages: function() {
var self = this,
room_id = App.getPath('current_room.id');
this.store.filter(App.ChatMessage, {room_id: room_id}, function (msg) {
return msg.get('roomId') === room_id;
})
// set content only after promise has resolved
.then(function (messages) {
self.set('content', messages);
});
}
You could also do this in the model hook without the extra clutter, because the model hook will accept a promise directly:
model: function() {
var self = this,
room_id = App.getPath("current_room.id");
return this.store.filter(App.ChatMessage, {room_id: room_id}, function (msg) {
return msg.get('roomId') === room_id;
});
}
My reading of the source (DS.Store.find) shows that what you'd actually be receiving in this instance is an AdapterPopulatedModelArray. A FilteredModelArray would auto-update as you create records. There are passing tests for this behaviour.
As of ember.data 1.13 store.filter was marked for removal, see the following ember blog post.
The feature was made available as a mixin. The GitHub page contains the following note
We recommend that you refactor away from using this addon. Below is a short guide for the three filter use scenarios and how to best refactor each.
Why? Simply put, it's far more performant (and not a memory leak) for you to manage filtering yourself via a specialized computed property tailored specifically for your needs