The project I'm working on uses the feathers JS framework server side. Many of the services have hooks (or middleware) that make other calls and attach data before sending back to the client. If I have a new feature that needs to query a database but for a only few specific things I'm thinking I don't want to use the already built out "find" method for this database query as that "find" method has many other unneeded hooks and calls to other databases to get data I do not need for this new query on my feature.
My two solutions so far:
I could use the standard "find" query and just write if statements in all hooks that check for a specific string parameter that can be passed in on client side so these hooks are deactivated on this specific call but that seems tedious especially if I find this need for several other different services that have already been built out.
I initialize a second service below my main service so if my main service is:
app.use('/comments', new JHService(options));
right underneath I write:
app.use('/comments/allParticipants', new JHService(options));
And then attach a whole new set of hooks for that service. Basically it's a whole new service with the only relation to the origin in that the first part of it's name is 'comments' Since I'm new to feathers I'm not sure if that is a performant or optimal solution.
Is there a better solution then those options? or is option 1 or option 2 the most correct way to solve my current issue?
You can always wrap the population hooks into a conditional hook:
const hooks = require('feathers-hooks-common');
app.service('myservice').after({
create: hooks.iff(hook => hook.params.populate !== false, populateEntries)
});
Now population will only run if params.populate is not false.
Related
Creating new project with auto-testing feature.
It uses basic express.
The question is how to orginize the code in order to be able to test it properly. (with mocha)
Almost every controller needs to have access to the database in order to fetch some data to proceed. But while testing - reaching the actual database is unwanted.
There are two ways as I see:
Stubbing a function, which intends to read/write from/to database.
Building two separate controller builders, one of each will be used to reach it from the endpoints, another one from tests.
just like that:
let myController = new TargetController(AuthService, DatabaseService...);
myController.targetMethod()
let myTestController = new TargetController(FakeAuthService, FakeDatabaseService...);
myTestController.targetMethod() // This method will use fake services which doesnt have any remote connection functionality
Every property passed will be set to a private variable inside the constructor of the controller. And by aiming to this private variable we could not care about what type of call it is. Test or Production one.
Is that a good approach of should it be remade?
Alright, It's considered to be a good practice as it is actually a dependency injection pattern
I am wondering about the security of apps script libraries. If a user imports a library, is there any way for them to retrieve the code within the library?
I ask because I am writing a library that connects many sheets to a single sheet which acts like a database. Users of the many sheets should not be able to find the database sheet.
I have tested console logging the functions, and they just return [Function] and not the actual function definition. However I still don't know if this is a safe implementation or not. Would love to hear your thoughts.
For other users to use your library, you have to give them access by sharing the script.
Authorized users can view the function code by printing the function or going to the script link
Using print:
Using script link:
https://script.google.com/d/(Script ID Here)/edit
In your post above, you want to hide any data that will lead users to database sheet.
I suggest to create a temporary function in your library script that will set a property containing the Sheet ID. This can be done by using Properties Service. Using this service will allow you to store strings as key-value pairs scoped to one script.
Example:
function setProperty(){
PropertiesService.getScriptProperties().setProperty("Sheet_ID", "123456");
}
Usage:
function myFunction() {
var databaseID = PropertiesService.getScriptProperties().getProperty("Sheet_ID");
SpreadsheetApp.getActiveSpreadsheet().getSheetId(databaseID)
}
Note: Before deploying your library script, run the setProperty() function and delete it in your script editor. This will prevent users from viewing the source code for setProperty() function. Also, make sure that the role of the users you will authorize to access your library is Viewer only to prevent them from editing your script and printing the Property value.
Reference:
Properties Service
As per the title, can a Node.js package require a database connection?
For example, I have written a specific piece of middlware functionality that I plan to publish via NPM, however, it requires a connection to a NoSQL database. The functionality in its current state uses Mongoose to save data in a specific format and returns a boolean value.
Is this considered bad practice?
It is not a bad practice as long as you require the DB needed and also explicitly state it clearly in your Readme.md file, it's only a bad practice when you go ahead and work without provide a comment in your codes or a readme.md file that will guide any other person going through your codes.
Example:
//require your NoSQL database eg MongoDB
const mongoose = require('mongoose');
// to connect to the database. **boy** is the database name
mongoose.connect('mongodb://localhost/boy', function(err) {
if (err) {
console.log(err);
} else {
console.log("Success");
}
});
You generally have two choices when your module needs a database and wants to remain as independently useful as possible:
You can load a preferred database in your code and use it.
You can provide the developer using your module a means of passing in a database that meets your specification to be used by your module. The usual way of passing in the database would be for the developer using your module to pass your module the data in a module constructor function.
In the first case, you may need to allow the developer to specify a disk store path to be used. In the second case, you have to be very specific in your documentation about what kind of database interface is required.
There's also a hybrid option where you offer the developer the option of configuring and passing you a database, but if not provided, then you load your own.
The functionality in its current state uses Mongoose to save data in a specific format and returns a boolean value. Is this considered bad practice?
No, it's not a bad practice. This would be an implementation of option number 1 above. As long as your customers (the developers using your module) don't mind you loading and using Mongoose, then this is perfectly fine.
I have a few PHP scripts which I am in the process of migrating to Node.js. I am using Sails.js for this and I would like to know how I can change databases for each request based on a request parameter.
Currently I have 3-4 identical PostgreSQL databases. Let's just say that each database corresponds to a different client.
Below is a segment of the current PHP script where the database connection is established:
$database = $_GET['db'];
$conn_details = "host=localhost port=5432 dbname=$database user=****** password=******";
$dbconn = pg_connect($conn_details);
Here you can see that the database name is coming from the request parameter "db".
I would like to have a similar functionality in my sails.js controller. I know that i can declare multiple databases in the connections.js and that I can have models use different databases but what i am after is for the models to stay the same and only the database to change based on each request.
I have found 2 similar questions but they have both stayed unanswered for quite some time now. (Here and here)
I think you are looking for something like sub apps
sails-hook-subapps
but it's experimental module. So i wouldn't recommend using it on production. Other option also not good is multiplying your Models like that:
One main model with all methods, attributes and "stuff"
Many models with connections config
In 'parent' model you will select to which model you want to send send action. For example write method:
getModel: function(dbName){
return models[dbName];
}
in models Object you will store all Models with different connections. Not sure how validators will works in this scenario. You need to test if it will not be required do do something like this in child Models
attributes: parentModel.attributes
I am using loopback without the strongloop framework itself, meaning I have no access to any of the cli tools. I am able to succesfully create and launch a loopback server and define/load some models in this fashion:
var loopback = require('loopback');
var app = loopback();
var dataSource = app.dataSource
(
'db',
{
adapter : 'memory'
});
);
var UserModel = app.loopback.findModel('User');
UserModel.attachTo(dataSource);
app.model(UserModel);
/* ... other models loading / definitions */
// Expose API
app.use('/api', app.loopback.rest());
What I would like to achieve is to be able to detach a model from the loopback application at runtime, so it is not available from the rest API nor the loopback object anymore (without the need to restart the node script).
I know it is possible to remove a model definition made previously from the cli:
Destroy a model in loopback.io, but this is not valid in my case since what it does is to remove the json objects that are loaded at strongloop boot, which is not applicable here.
I would appreciate very much any help regarding this, I have found nothing in the strongloop API documentation.
Disclaimer: I am a core developer of LoopBack.
I am afraid there is no easy way for deleting models at runtime, we are tracking this request in issue #1590.
so it is not available from the rest API nor the loopback object anymore
Let's take a look at the REST API first. In order to remove your model from the REST API, you need to remove it from the list of "shared classes" maintained by strong-remoting and then clean the cached handler middleware.
delete app.remotes()._classes[modelName];
delete app.remotes()._typeRegistry._types[modelName];
delete app._handlers.rest;
When the next request comes in, LoopBack will create a new REST handler middleware and rebuild the routing table.
In essence, you need to undo the work done by this code.
In order to remove the model from LoopBack JavaScript APIs, you need to remove it from the list of models maintained by application's registry:
delete app.models[modelName];
delete app.models[classify(modelName)];
delete app.models[camelize(modelName)];
app.models.models.splice(app.models.indexOf(ModelCtor), 1);
(This is undoing the work done by this code).
Next, you need to remove it from loopback-datasource-juggler registries:
delete app.registry.modelBuilder.models[modelName];
Caveats:
I haven't run/tested this code, it may not work out of the box.
It does not handle the case where the removed model has relations with other models.
It does not notify loopback-component-explorer about the change in the API
Update
There's now a function called deleteModelByName that does exactly that.
https://apidocs.strongloop.com/loopback/#app-deletemodelbyname
https://github.com/strongloop/loopback/pull/3858/commits/0cd380c590be7a89d155e5792365d04f23c55851