I ' ve some troubles , managing my i18n in my database
For now I ' just two languages available on my application , but in order to be scalable, I would like to do it the "best" way.
I could have duplicated all fields like description_fr, description_en but I was no confortable with this at all. What I've done for now, is a external table , call it content, and its architecture is like this :
id_ref => entity referenced id (2)
type => table name (university)
field => field of the specific table (description)
lang => which lang (fr, en, es…)
content => and finally the appropriate content.
I think it can be important to precise, I use sequelizeJS as ORM. So I can use a usefull hooks as afterFind, afterCreate and afterUpdate. So Each time I wanna to find a resource for example, after find it, my hook retrieve all content for this resource and set definitly my object with goods values. It works, but I'm not in love with this.
But I have some troubles with this :
It's increase considerably my number of requests to the database : If I select 50 rows for example, I have to do 50 requests more.. , and just for a particular model. If I have nested models, it's exponential…
Then, It's complicated to fetch data by content i18ned. Example find a university with a specific name is complicated.
And It's a lot of work for updating etc...
So I wonder, if it would be a good idea , to save as a JSON, directly in the table concerned , the data. Something like
{
fr : { 'name':'Ma super université' },
en : { 'name':'My kick ass university' }
}
And keep on using Sequelize Hooks to build and insert proper data into my object.
What do you think ?
How do you manage this ?
EDIT
I use a mysql database
It concerns around 20 fields (cross models)
I have to set the default value using a my default_lang if there is no content set (e.g, event.description in french will be the same as the english one, if there is no content set)
I used this npm package sequelize-i18n. It worked pretty fine for me using sequelize 3.23.2, unfortunately it seems does not have support for sequelize 4.x yet.
Related
I'm able to generate query for multi inserts or update thanks to pg-promise helpers but I was wondering if I could follow the advice of the author and put all queries outside of my javascript code (See here https://github.com/vitaly-t/pg-promise/wiki/SQL-Files and here : https://github.com/vitaly-t/pg-promise-demo).
When I use the insert helpers, the return query looks like :
INSERT INTO "education"("candidate_id","title","content","degree","school_name","start_date","still_in","end_date","picture_url") VALUES('6','My degree','Business bachelor','Bachelor +','USC','2018-05-15T02:00:00.000+02:00'::date,false,null::date,null),('6','Another degree','Engineering','Master degree','City University','2018-05-15T02:00:00.000+02:00'::date,false,null::date,null)
The idea is that I don't know how many inserts I want to do at the same time, so it has to be dynamic.
The following code doesn't work as I'm passing an array of object instead of an object :
db.none(`INSERT INTO "education"("candidate_id","title","content","degree","school_name","start_date","still_in","end_date","picture_url")
VALUES($<candidate_id>, $<title>, $<content>, $<degree>, $<school_name>, $<start_date>, $<still_in>, $<end_date>, $<picture_url>)`, data)
This code spreads the object but is still not correct to make a proper query :
db.none(`INSERT INTO "education"("candidate_id","title","content","degree","school_name","start_date","still_in","end_date","picture_url")
VALUES($1:list)`,
[data])
Any idea ? Is it at least possible or in the case where I don't know how many records I want to insert in advance I have to call pgp.helpers everytime ?
You confuse static and dynamic SQL. SQL files are there for SQL queries that are mainly static, i.e. you still can inject dynamically a lot, but when most of the query is dynamic, there is no longer any point putting it into an SQL file.
And the helpers namespace is there for dynamic queries only. So you are asking about two separate things, to join things that do not need to be joined.
The Situation
I recently started working on a new project using nodejs. I have a background of using Python/Django and C#/.NET (not a huge fan of the latter). Node is awesome, but I must say I miss the ease of building models and automating migrations in Django. I am currently using the AdonisJS framework which leverages Knex. Knex is a powerful library, but the migrations all need to be manually built. Additionally, the AdonisJS ORM that manages the Models is independent of Knex (migration manager). You also do not define field attributes on the Models, which can have benifits for dynamically doing things in the front and back end. All things considered, there is a lot of room for human error, miscommunication and a boat load more typing required. I know the the hot thing these days is to keep it loose and fast, but for this specific project, I am looking for a bit more structure than loosely defined models.
Current State
What I have landed on is building a new Class called tableModel and a field class to define the fields within table model. I have already completed this and I am successfully writing the migration files leveraging mustache. I plan on also automatically writing the Models which I shouldn't have a problem with (fingers crossed).
The Problem
Here is where it gets a little tough and where I need help...I need to track what has been added or removed via migration so I can effectively write ups and downs as the tableModels change over time.
So let's say I add a "tableModel" which creates a migration to create table Foo with fields {id (bigint), user_id(int), name(string255)}
Later I want to add a field called description so I would simply add it to my "tableModel" and then run a build command which would build out the migration.
How do I check what has already been created though so I only do an up() for description?
Then I want to remove the name field so I mark it out in my "tableModel" and run a build migration command. How do I check what has been migrated that now needs to be added in to the down().
Edit: I would add a remove field to the up and the corresponding roll back to the down.
Bonus Round
Let's say I want to change user_id from an int to a bigint, because who makes a foreign key just an int? How do I check not just what needs to be added to the up and down, but also checks if I need to change a property on a field.
Edit: would just write the up. and a corresponding roll back to the down
The Big Question
Basically, how do I define dirty "tableModels" classes
Possible Solution?
I am thinking that maybe I should capture some type of registry or snapshot and then run the comparison when building the migrations and or models, then recapture/snapshot. If this is the route, should I store in a json file, write this to the DB itself, or is there another/better option.
If I create the tableModel instances as constants, could I actually write back to the JS file and capture the snapshot as an attribute? IF this is an option, is Node's file system the way to go and what's the best way to do this? Node keep suprising me so I wouldn't be baffled if any of these are an option.
Help!
If anyone has gone down this path before or knows of any tools I could leverage, I would greatly appreciate it and thank you in advance. Also, if I am headed in a completely wrong direction, then please let me know, I both handle and appreciate all types of feedback.
Example
Something to note, when I define the "tableModel" for a given migration or model, it is an instance of the class, I am not creating an extended class since this is not my orm.
class tableModel {
constructor(tableName, modelName = tableName, fields = []) {
this.tableName = tableName
this.modelName = modelName
this.fields = fields
}
// Bunch of other stuff
}
fooTableModel = new tableModel('fooTable', 'fooModel', fields = [
new tableField.stringField('title'),
new tableField.bigIntField('related_user_id'),
new tableField.textField('description','Testing Default',false,true)
]
)
which equates to:
tableModel {
tableName: 'fooTable',
modelName: 'fooModel',
fields:
[ stringField {
name: 'title',
type: 'string',
_unique: false,
allow_null: null,
fieldAttributes: {},
default_value: null },
bigIntField {
name: 'related_user_id',
type: 'bigInteger',
_unique: false,
allow_null: null,
fieldAttributes: {},
default_value: 0 },
textField {
name: 'description',
type: 'text',
_unique: false,
allow_null: true,
fieldAttributes: {},
default_value: 'Testing Default' } ]
You have the up and down notation mixed up. Those are for migrating the "latest" (runs the up function) and doing rollbacks (runs the down function). Up and down to not relate to dropping or adding table columns.
The migrations up is for any change, and the down is to reverse those changes. So if you wanted to drop a column from some table, you write the command in the up, then write the opposite in the down (you'd add it back in...), such that you can "rollback" and the change is effectively reversed. You have to be careful with such things though, as you can put yourself in a situation where you actually lose data.
Want to add a column? Write it in the up, and drop the column in the down.
One of the major points behind the migrations mechanism is to track the state of changes of your database, as time goes forward. So generally, if you created a table in some migration, then a day or so later you realize you need to drop/add columns, you normally don't go back and edit the existing migration, especially if the migration has already been run. You'd just write a new migration to drop/add your column.
Since you're using knex, there are a couple "knex" tables that get created. By default the one you're looking for is knex_migrations, unless someone specifically modified the settings to change the name of it. This table holds all the migrations that have run against your DB, per batch. From the CLI, assuming you have knex.js installed globally, you can run knex migrate:latest, and that will push all the migrations that exist in your directory to the target database, if they have not yet been run. It does this by way of examining that knex_migrations table. If you roll a change and don't like it, and assuming you've properly done the down function, you can invoke knex migrate:rollback to reverse the change. If there are 3 migration files that have NOT yet been run, invoking knex migrate:latest will run all 3 of those migration files under a new batch #, which is 1 higher than the most recent batch number. Conversely, if you invoke a knex migrate:rollback, it will find the highest batch number (there could be more than 1 migration in a batch...), and invoke the down function on all those files, effectively rollback those changes.
All that said, knex is a "query builder" tool. It's got a ton of helper functions to help build the sql for you. Personally, I find this to be a major distraction. Why spend hours on hours figuring out all the helper functions when I can just go crank out raw SQL and run that. Thus, that's what we've done in our system. we use knex.raw('') and write our own DDL and DML. It works great and does exactly what we need it to. We don't need to go figure out the magic of the query building.
The short answer is that knex will automatically know what has and has not been run for you (again, via that knex_migrations table it creates for you...).
Things can get weird though when it start involving git and different branches. I recommend that if you're writing migrations on some branch, and you need to go do other work, always remember to first perform a rollback of any migrations you've done in that branch BEFORE switching branches. Otherwise you will be in weird DB states that don't coincide with the application code.
I would personally just deal with updating models independently of writing migrations. For example, if I'm adding a description column to some table, then I probably want to manually update the ORM to reflect the change of the new db schema. Generally, I've found trying to use a tool that automagically does that for you (rather, if I change the orm, stuff happens to write all the underlying sql...) usually winds me up in a heap of trouble and I just spend more time trying to un-fudge stuff. But, that's just my 2 cents :)
Here is where it gets a little tough and where I need help...I need to track what has been added or removed via migration so I can effectively write ups and downs as the tableModels change over time.
You could store changes in a DB/txt file and those can act as snapshots. So when you want to rollback to a particular migration, you would find the changes (up/down) made for that mutation and adjust accordingly.
Later I want to add a field called description so I would simply add it to my "tableModel" and then run a build command which would build out the migration. How do I check what has already been created though so I only do an up() for description?
Here you either call the database itself directly and check what fields have already been created. If a field is already their and the attributes are the same, you can either ignore it or stop the transaction all together.
Bonus Round Let's say I want to change user_id from an int to a bigint, because who makes a foreign key just an int? How do I check not just what needs to be added to the up and down, but also checks if I need to change a property on a field.
Again, call the DB itself on the table in question. I know the SQL call would be:
describe [table_name];
After reading the end, I think you answered this yourself, but I think capturing these changes would work best in a NoSql database since you're using Node or PostGres with it's json field.
TLDR
Is there a way to limit queryByExample to a collection in NodeJS?
Problem faced
I have a complex query with some optional fields (i.e. sometimes some search fields will be omitted). So I need to create a query dynamically, e.g. in JSON. QueryByExample seems to be the right tool to use here as it gives me that flexibility to pass a JSON. However my problem is that I would like to limit my search to only one collection or directory.
e.g. I was hoping for something like
searchJSON = {
title: { $word: "test" },
description: { $word: "desc" }
};
//query
db.documents.query(qb.where(
qb.collection("collectionName"),
qb.byExample(searchJSON)
)).result()...
In this case searchJSON could have been built dynamically, for example maybe sometimes title may be omitted from the search.
This doesn't work because the query builder only allows queryByExample to be the only query. But I'd instead like to built a dynamic search query which is limited to a collection or directory.
At present, I think you would have to express the query with QueryBuilder instead of Query By Example using
qb.and([
qb.collection('collectionName'),
qb.word('title', 'test'),
qb.word('description', 'desc')
])
See http://docs.marklogic.com/jsdoc/queryBuilder.html#word
That said, it should be possible for the Node.js API to relax that restriction based on the fixes in MarkLogic 9.0-2
Please file an issue on https://github.com/marklogic/node-client-api
I am building a REST API which connects to a NEO4J instance. I am using the koa-neo4j library as the basis (https://github.com/assister-ai/koa-neo4j-starter-kit). I am a beginner at all these technologies but thanks to some help from this forum I have the basic functionality working. For example the below code allows me to create a new node with the label "metric" and set the name and dateAdded propertis.
URL:
/metric?metricName=Test&dateAdded=2/21/2017
index.js
app.defineAPI({
method: 'POST',
route: '/api/v1/imm/metric',
cypherQueryFile: './src/api/v1/imm/metric/createMetric.cyp'
});
createMetric.cyp"
CREATE (n:metric {
name: $metricName,
dateAdded: $dateAdded
})
return ID(n) as id
However, I am struggling to know how I can approach more complicated examples. How can I handle situations when I don't know how many properties will be added when creating a new node beforehand or when I want to create multiple nodes in a single post statement. Ideally I would like to be able to pass something like JSON as part of the POST which would contain all of the nodes, labels and properties that I want to create. Is something like this possible? I tried using the below Cypher query and passing a JSON string in the POST body but it didn't work.
UNWIND $props AS properties
CREATE (n:metric)
SET n = properties
RETURN n
Would I be better off switching tothe Neo4j Rest API instead of the BOLT protocol and the KOA-NEO4J framework. From my research I thought it was better to use BOLT but I want to have a Rest API as the middle layer between my front and back end so I am willing to change over if this will be easier in the longer term.
Thanks for the help!
Your Cypher syntax is bad in a couple of ways.
UNWIND only accepts a collection as its argument, not a string.
SET n = properties is only legal if properties is a map, not a string.
This query should work for creating a single node (assuming that $props is a map containing all the properties you want to store with the newly created node):
CREATE (n:metric $props)
RETURN n
If you want to create multiple nodes, then this query (essentially the same as yours) should work (but only if $prop_collection is a collection of maps):
UNWIND $prop_collection AS props
CREATE (n:metric)
SET n = props
RETURN n
I too have faced difficulties when trying to pass complex types as arguments to neo4j, this has to do with type conversions between js and cypher over bolt and there is not much one could do except for filing an issue in the official neo4j JavaScript driver repo. koa-neo4j uses the official driver under the hood.
One way to go about such scenarios in koa-neo4j is using JavaScript to manipulate the arguments before sending to Cypher:
https://github.com/assister-ai/koa-neo4j#preprocess-lifecycle
Also possible to further manipulate the results of a Cypher query using postProcess lifecycle hook:
https://github.com/assister-ai/koa-neo4j#postprocess-lifecycle
I find myself doing a lot of queries to fetch just the first couple of items of a big set, e.g. to show the three most recent news articles or blog posts on the homepage of a website.
As long as this query only involves predefined or custom Parts, I can do something like this:
public IEnumerable<ContentItem> GetTopArticles(int amount)
{
var cultureRecord = _cultureManager.GetCultureByName(_orchardServices.WorkContext.CurrentCulture);
var articles = _orchardServices.ContentManager.Query().ForType("Article")
.Where<LocalizationPartRecord>(lpr => lpr.CultureId == cultureRecord.Id)
.OrderBy<CommonPartRecord>(cpr => cpr.PublishedUtc)
.Slice(0, amount);
return articles;
}
I'm assuming this will more or less be the same as a SELECT TOP [amount] ... in SQL and will have good performance on a large number of records.
However, sometimes I use Migrations or Import to create Content Types from an external source and want to conditionally check a field from the generic Part. In this case I don't have a Part or PartRecord class that I can pass as a parameter to the ContentQuery methods and if I want to do a conditional check on any of the fields I currently do something like this:
public IEnumerable<ContentItem> GetTopArticles(int amount)
{
var articles = _orchardServices.ContentManager.Query().ForType("Article")
.OrderBy<CommonPartRecord>(cpr => cpr.PublishedUtc)
.List()
.Where(a => a.Content.Article.IsFeatured.Value == true)
.Take(amount);
return articles;
}
This is really wasteful and causes large overhead on big sets but I really, REALLY, do not want to delve into the database to figure out Orchard's inner workings and construct long and complex HQL queries every time I want to do something like this.
Is there any way to rewrite the second query with IContentQuery methods without incurring a large performance hit?
I'm working on something similar (being able to query model data with a dynamic name). Sadly, I haven't found anything that makes it easy.
The method I've found that works is to do plain SQL queries against the database. Check out this module for syntax on that if you do later find yourself willing to delve into the database.