How can I make $httpBackend insensitive to the order of URL query parameters?

Question

I am using the Angular.js $httpBackend to test some services that wrap $http calls (this is in ngMock, not ngMockE2E).

It seems that things like expect and when are sensitive to the order of URL query parameters. E.g. if I do $httpBackend.when('POST','/apiCall?X=1&Y=2').respond(/* ... */) or $httpBackend.expectPOST('/apiCall?X=1&Y=2'), I get URL mismatches if I have Y=2&X=1 in the URL instead of X=1&Y=2.

I want to write my tests in such a way that the service being tested will be free to change the order of URL query string parameters without breaking the tests. I haven't been able to find anything to solve this in the $httpBackend documentation. What's the right way to do this?

Answer 1

angular will sort the keys of the params object used in conjunction with $http.

$http({
    url:"/myurl",
    method:"GET",
    params:{
       Y:1
       X:2
    }}); 

Angular will do the following effectively: Object.keys(myParams).sort() and append the keys in that order. which ends up being '/myurl?X=2&Y=1'

I would suggest consistently using query parameters not directly in the url, but instead in the parameter params: that angular will then process.

Another solution would be to use Regular Expressions in your tests, something like

$httpBackend.expectPOST(/\/myurl\?((X|Y)=\d{1,}&?){2}/) regexper

The fact that you can use RegExp's is really hard to spot since the documentation redesign, as the colors do not blend.

Answer 2

you can use the $httpParamSerializer service to achieve this:

$httpParamSerializer({ param: 1, param2: 2 });

This will return you a matching stringified querystring matching angulars $http service with params.