Here is the javascript object I'm trying to convert to a query string
{$and: [{topic: categoryIds} , {$or :[ {'groups 1': {$ne: ''}}, {groups: $scope.myGroups}]}]};
Basically I'm looking to match a topic that equals a categoryIds and grab documents that have an empty groups array or that the groups array has values and matches one in the array $scope.mygroups
My question is what would be best practice to convert this in an easily parseable format so I can append it to a GET request, and how would you go about parsing it on the express server.
I am using this code in production for querying against a server with a MongoDB backend (using angular and lodash):
.factory('mongoQuery', function() {
return {
fromJson: function(json) {
return JSON.parse(json, fromJsonReviver);
},
toJson: function(object) {
return JSON.stringify(object, toJsonReplacer);
}
};
function fromJsonReviver(key, value) {
var val = value;
if (_.isPlainObject(value)) {
if (_.isNumber(value.$date)) {
val = new Date(0);
val.setUTCMilliseconds(value.$date * 1000);
} else if (_.isString(value.$regexp)) {
var match = /^\/(.*)\/([gimy]*)$/.exec(value.$regexp);
val = new RegExp(match[1], match[2]);
}
}
return val;
}
function toJsonReplacer(key, value) {
var val = value;
if (_.isPlainObject(value)) {
val = _.extend({}, value);
for (var k in value) {
val[k] = toJsonReplacer(k, val[k]);
}
} else if (_.isDate(value)) {
val = {$date: (new Date(value)).valueOf() / 1000};
} else if (_.isRegExp(value)) {
val = {$regexp: value.toString()};
}
return val;
}
})
It includes many of the suggestions mentioned by others in the comments and supports dates and regular expressions.
Other than that, if you need to send the query with a GET request, just use encodeURIComponent like others have mentioned.
Here is a working example: http://plnkr.co/edit/b9wJiUkrHMrDKWFC1Sdd?p=preview
What you're thinking here is basically to redevelop an API server, coupled with some mongodb database, and querying it with some format.
REST is the "best practise" you're looking for. It's a standard that encapsulates some common actions to http ressources.
You should know that you don't need to redevelop an ecosystem based on such a standard. Full-featured REST API servers exist, some are even based on express.js. Loopback and sails.js. These one provide some extra features like
Model abstraction through ORM's, and database-engine agnostism
Automatic REST actions, from database schema or model finition
Advanced querying through "extended REST" ("where", "limit", "order", ...)
Realtime with REST-like websockets
Client side libraries that help you query the server
Some standalone exernal libraries, such as js-data or Restangular can deal with REST server pretty well, and act as a frontend connector to backend
Now, if I had to purely answer your question, and if you realy wanted to go with your solution, I'd just add the mongo query to a where query param on the http call with encodeURIComponent as stated before.
Related
I am trying to use the Client Libraries provided by Google to move traffic from one version of an app in AppEngine to another. However, the documentation for doing this just talks about using the rest API and not the client libraries.
Here is some example code:
var servicesClient = Google.Cloud.AppEngine.V1.ServicesClient.Create();
var updateServiceRequest = new UpdateServiceRequest();
updateServiceRequest.Name = "apps/myProject/services/myService";
var updateMask = new Google.Protobuf.WellKnownTypes.FieldMask();
updateServiceRequest.UpdateMask = updateMask;
// See below for what should go here...
var updateResponse = servicesClient.UpdateService(updateServiceRequest);
My question is what format do I use for the update mask?
According to the documentation I should put in:
split {"split": { "allocations": { "newVersion": 1 } } }
But when I try: updateMask.Paths.Add(#"split { ""split"": { ""allocations"": { ""myNewVersion"": 1 } } }");
... I get the exception:
"This operation is only supported on the following field(s): [labels, migration_config, network_settings, split, tag_to_target_map], but got field(s): [split { "split": { "allocations": { "myNewVersion": 1 } } }] from the update request.
Any ideas where I should put the details of the split in the field mask object? The property Paths just seems to be a collection of strings.
The examples for these libraries in Google's doco is pretty poor :-(
I raised a support ticket with Google and despite them suggesting a solution which didn't work exactly (due to trying to assign a string to the UpdateMask which needs a FieldMask object), I managed to use it to find the correct solution.
The code should be:
// appService is a previously retrieved Service object from the ListServices method
var updateServiceRequest = new UpdateServiceRequest();
updateServiceRequest.Name = appService.Name;
updateServiceRequest.UpdateMask = new Google.Protobuf.WellKnownTypes.FieldMask();
updateServiceRequest.UpdateMask.Paths.Add("split");
appService.Split.Allocations.Clear();
appService.Split.Allocations["newServiceVerison"] = 1;
updateServiceRequest.Service = appService;
I have a site with hundreds of members who would like to see activity relating to their products. We use datastudio at the moment, creating a report manually for a few who have asked.
We would like to be able to send out a single report that grabs the member details from the url and sets the report to that member. We followed the datastudio docs https://developers.google.com/datastudio/solution/viewers-cred-with-3p-credentials but it's not very clear
function getAuthType() {
var response = { type: 'NONE' };
return response;
}
function getConfig(request) {
var cc = DataStudioApp.createCommunityConnector();
var config = cc.getConfig();
config
.newTextInput()
.setId('token')
.setName('Enter user token')
.setAllowOverride(true);
config.setDateRangeRequired(false);
config.setIsSteppedConfig(false);
return config.build();
}
function getFields(request) {
var cc = DataStudioApp.createCommunityConnector();
var fields = cc.getFields();
var types = cc.FieldType;
fields.newDimension()
.setId('tokenValue')
.setType(types.TEXT);
return fields;
}
function getSchema(request) {
var fields = getFields(request).build();
return { schema: fields };
}
function getData(request) {
var token = request.configParams.token;
}
Has anyone set up a community connector that would allow multiple users to see a single report but only see what's specific to them?
I'm not sure if the token is being set property. It displays as the placeholder only. Is there a way to be sure what value my parameter is assigned?
We haven't got the the point of passing a url parameter. What we would like to do is pass the token value (Member details) to an existing filter. Is this possible in a community connector?
You can use the Filter by email address feature to filter your data based on the viewer's email address. This works out of the box and won't require you to build a custom connector.
Alternatively, if you do want to build a custom connector, follow this guide that seems more suitable for your use case.
I have a nodejs application where i connect to my couchdb using nano with the following script:
const { connectionString } = require('../config');
const nano = require('nano')(connectionString);
// creates database or fails silent if exists
nano.db.create('foo');
module.exports = {
foo: nano.db.use('foo')
}
This script is running on every server start, so it tries to create the database 'foo' every time the server (re)starts and just fails silently if the database already exists.
I like this idea a lot because this way I'm actually maintaining the database at the application level and don't have to create databases manually when I decide to add a new database.
Taking this approach one step further I also tried to maintain my design docs from application level.
...
nano.db.create('foo');
const foo = nano.db.use('foo');
const design = {
_id: "_design/foo",
views: {
by_name: {
map: function(doc) {
emit(doc.name, null);
}
}
}
}
foo.insert(design, (err) => {
if(err)
console.log('design insert failed');
})
module.exports = {
foo
}
Obviously this will only insert the design doc if it doesn't exist. But what if I updated my design doc and want to update it?
I tried:
foo.get("_design/foo", (err, doc) => {
if(err)
return foo.insert(design);
design._rev = doc._rev
foo.insert(design);
})
The problem now is that the design document is updated every time the server restarts (e.g it gets a new _rev on every restart).
Now... my question(s) :)
1: Is this a bad approach for bootstrapping my CouchDB with databases and designs? Should I consider some migration steps as part of my deployment process?
2: Is it a problem that my design doc gets many _revs, basically for every deployment and server restart? Even if the document itself hasn't changed? And if so, is there a way to only update the document if it changed? (I thought of manually setting the _rev to some value in my application but very unsure that would be a good idea).
Your approach seems quite reasonable. If the checks happen only at restarts, this won't even be a performance issue.
Too many _revs can become a problem. The history of _revs is kept as _revs_info and stored with the document itself (see the CouchDB docs for details). Depending on your setup, it might be a bad decision to create unnecessary revisions.
We had a similar challenge with some server-side scripts that required certain views. Our solution was to calculate a hash over the old and new design document and compare them. You can use any hashing function for this job, such as sha1 or md5.
Just remember to remove the _rev from the old document before hashing it, or otherwise you will get different hash values every time.
I tried the md5 comparison like #Bernhard Gschwantner suggested. But I ran into some difficulties because im my case I'd like to write the map/reduce functions in the design documents in pure javascript in my code.
const design = {
_id: "_design/foo",
views: {
by_name: {
map: function(doc) {
emit(doc.name, null);
}
}
}
}
while getting the design doc from CouchDb returns the map/reduce functions converted as strings:
...
"by_name": {
"map": "function (doc) {\n emit(doc.name, null);\n }"
},
...
Obviously md5 comparing does not really work here.
I ended up with the very simple solution by just putting a version number on the design doc:
const design = {
_id: "_design/foo",
version: 1,
views: {
by_name: {
map: function(doc) {
emit(doc.name, null);
}
}
}
}
When I update the design doc, I simply increment the version number and compare it with the version number in database:
const fooDesign = {...}
foo.get('_design/foo', (err, design) => {
if(err)
return foo.insert(fooDesign);
console.log('comparing foo design version', design.version, fooDesign.version);
if(design.version !== fooDisign.version) {
fooDesign._rev = design._rev;
foo.insert(fooDesign, (err) => {
if(err)
return console.log('error updating foo design', err);
console.log('foo design updated to version', fooDesign.version)
});
}
});
Revisiting your question again: In a recent project I used the great couchdb-push module by Johannes Schmidt. You get conditional updates for free, alongside with many other benefits inherited from its dependency couchdb-compile.
That library turned out to be a hidden gem for me. HIGHLY recommended!
I've been tasked with adding an Angular Typeahead search field to a site and the data needs to come from multiple tables. It needs to be a "search all the things" kind of query which looks for people, servers, and applications in one spot.
I was thinking the best way to do this would be to have a single API endpoint in Sails which could pull from 3 tables on the same DB and send the results, but I'm not quite sure how to go about it.
Use the built-in bluebird library, specifically Promise.all(). To handle the results, use .spread(). Example controller code (modify to suit your case):
var Promise = require('bluebird');
module.exports = {
searchForStuff: function(req, res) {
var params = req.allParams();
// Replace the 'find' criteria with whatever suitable for your case
var requests = [
Person.find({name: params.searchString}),
Server.find({name: params.searchString}),
Application.find({name: params.searchString})
];
Promise.all(requests)
.spread(function(people, servers, applications) {
return res.json({
people: people,
servers: servers,
applications: applications
})
})
}
}
I'm sending a model to server via $http.post, but, say, empty dates must be deleted, ids must be converted to int, in float values comma must be replaced with dot. These are restrictions of the server-side json api, so I'm looking for a way to modify $http request. Complicated part is that the modification rules depend on a api method name, which itself is a part of request.
The most straightforward way is to declare a modifying function and pass model to that function right before $http.post
$scope.method1Adapter = function(model) {
var data = angular.copy(model);
// 30 lines of modification code
return data;
};
$http.post("/api", {method: "method1", "data": $scope.method1Adapter($scope.data)})
but I think it's a little bit spaghettysh.
Better way is a factory that gets a method name and returns an adapter callback.
coreApp.factory("httpAdapter", function() {
return {
get: function (method) {
if (method == 'method1') {
return function (model) {
var data = angular.copy(model);
// modifications
return data;
}
} else {
return function (model) {
return model;
}
}
}
}
});
so i can add this to $httpProvider.defaults.transformRequest callbacks chain
coreApp.config(function($httpProvider, httpAdapterProvider) {
$httpProvider.defaults.transformRequest.unshift(function(post) {
if (post && post.data && post.data) {
post.data = httpAdapterProvider.$get().get(post.method)(post.method);
}
})
});
And still I don't like that, because api for my application has 16 methods, and it would require 5 adapters which is about 100 lines of code hard to maintain.
Any ideas about more clean and neat solution? Thank you.
I wouldn't chain adapters here because, as you said, it would be hard to maintain.
My advice would be to use the $http interceptors (not the responseInterceptors, which are deprecated, but the normal one, see http://docs.angularjs.org/api/ng.$http).
Notice in that you have access to the "config" object that has the request url, amongst other interesting properties.
It won't be superneat but at least the problem can be contained in one isolated part of your codebase.