This post indicates how to make a simple GET HTTP request with Erlang's Inets application.
Sometimes, URLs have GET parameters:
http://example.net/item?parameter1=12¶meter2=1431¶meter3=8765
Besides including the parameters in the URL itself, is there a way to create variables and then send them with the request?
Example appreciated.
ssl:start(),
application:start(inets),
httpc:request(post,
{"https://postman-echo.com/post",
[],"text/plain","parameter1=12¶meter2=1431¶meter3=8765"},
[], []).
You can use this example to use string interpolation to make a variable for parameter1..parameter3=8765.
Related
I have learned you can "decorate" the HTTP transport so that you can details of the request, however I can't quite figure out how you log the URL in the same line.
https://play.golang.org/p/g-ypQN9ceGa
results in
INFO[0000] Client request dns_start_ms=0 first_byte_ms=590 response_code=200 total_ms=590 url=
INFO[0000] 200
I'm perpetually confused if I should be using https://golang.org/pkg/context/#WithValue to pass around the context in a struct, especially in light where https://blog.golang.org/context-and-structs concludes with pass context.Context in as an argument.
Go through the behaviour of how the request is constructed in request.go from net/http. You see that the RequestURI field is never set there. Quoting from same reference,
Usually the URL field should be used instead.
It is an error to set this field in an HTTP client request
So, I would suggest you to use request.URL instead.
It is a parsed from the request uri. It should have the data you need.
You can construct the output as following:
f := log.Fields{
"url": fmt.Sprintf("%s %s%s", r.Method, r.URL.Host, r.URL.Path),
}
Also, in my experience, it is far more easier to use context.WithValue and pass the context as an argument.
Replace r.RequestURI by r.URL.String() in your code to log the full, valid URL (https://golang.org/pkg/net/url/#URL.String). RequestURI is empty on the client side (https://golang.org/pkg/net/http/#Request), as the output from your code is showing.
I don't see how context.Context relates to your question, but I believe https://blog.golang.org/context-and-structs is considered "best practice".
Following are the steps that I need to peform
Make http request call to a sevice which returns a json that has many urls.
Extract all the urls using regular expression extractor
Make http request call to all the exctracted urls asynchronously.
Is there a way we can achieve this? I tried parallel controller but, if I am not wrong, it requires all the request to be mentioned as its child sampler. I don't want to write each and every request manually. Is there a way we can change urls dynamically after running the test plan?
It's better to use JSON Extractor if the server returns URLs in JSON format
Once you have the URLs in form of JMeter Variables like:
url_1=http://example.com
url_2=http://example.org
........
........
url_matchNr=X
add Parallel Sampler to your Test Plan
add JSR223 PreProcessor as a child of the Parallel Sampler
Put the following code into "Script" area:
1.upto(vars.get('url_matchNr') as int, { index ->
sampler.addURL(vars.get('url_' + index))
})
I'm writting a RESTful api, and at I'm thinking about the process of a user creating a key. I have the following possibilities:
GET request to /new/<keyname> - although it's very easy I think I won't use this, because I heard GET is for retrieving and/or listing information;
POST request to /<keyname> - This seemed to me easy and simple enough, but does not pass any data in the request body. Can I do it this way ? Is this weird ?
POST request to /keys passing in the request body "keyname=SomeKey" - Is this the correct way ?
I looked at this API from joyent and in all their PUT and POST requests they pass some data in the request body. Is this expected ? Is it really wrong not to require a request body in a PUT and POST request ?
I asked this question on the Http-WG. This was the most precise answer I got http://lists.w3.org/Archives/Public/ietf-http-wg/2010JulSep/0276.html
In summary, POST does not require a body. I would expect the same justification can be applied to PUT.
RFC2616 is the base RFC for HTTP 1.1
In the most general form, an HTTP message is this (note the optional body):
generic-message = start-line
*(message-header CRLF)
CRLF
[ message-body ]
start-line = Request-Line | Status-Line
Reading further gives this:
9.5 POST
The POST method is used to request that the origin server accept the
entity enclosed in the request as a new subordinate of the resource
identified by the Request-URI in the Request-Line. ...
and
9.6 PUT
The PUT method requests that the enclosed entity be stored under the
supplied Request-URI. ...
The fundamental difference between the POST and PUT requests is
reflected in the different meaning of the Request-URI. The URI in a
POST request identifies the resource that will handle the enclosed
entity. That resource might be a data-accepting process, a gateway to
some other protocol, or a separate entity that accepts annotations.
In contrast, the URI in a PUT request identifies the entity enclosed
with the request -- the user agent knows what URI is intended and the
server MUST NOT attempt to apply the request to some other resource.
Both POST and PUT include the phrase entity enclosed in the request.
Based on my reading, I believe that a body is desired (a non-normative description, I know) for both POST and PUT.
In the context of REST, POST is create and PUT is update. I can imagine creating an empty object (perhaps a placeholder for future information), but I don't imagine much use of an empty update.
It is not required. You can send a POST/PUT request without a body and instead use query string parameters. But be careful if your parameters contain characters that are not HTTP valid you will have to encode them.
For example if you need to POST 'hello world' to and end point you would have to make it look like this: http://api.com?param=hello%20world
Probably the best way is your third option: POST to /keys with keyname=SomeKey.
Here's why: You may wish to add another function to your API, for example create_new_user. It would then be difficult to tell the difference between a user trying to POST a key called create_new_user and a user trying to use the create_new_user function.
You are correct in saying that you should not be using GET to do this operation as the GET operation "SHOULD NOT have the significance of taking an action
other than retrieval." (RFC 2616).
To answer your question in one line. Yes it is expected to have Body/Content in body, but it is not required(Mandatory).
According to okHttp3 (an HTTP library for android): the following methods need a body: POST, PUT, PATCH, PROPPATCH (WebDAV) and REPORT (source). It even crashes if you try to do a request with the given methods without a body.
I've written a RESTful web service that supports the standard CRUD operations, and that can return a set of objects matching certain criteria (a SEARCH verb), but I'd like to add a higher-order COUNT verb, so clients can count the resources matching search criteria without having to fetch all of them.
A few options that occur to me:
Ignoring the HTTP specification and returning the object count in the response body of a HEAD request.
Duplicating the SEARCH verb's logic, but making a HEAD request instead of a GET request. The server then would encode the object count in a response header.
Defining a new HTTP method, COUNT, that returns the object count in the response body.
I'd prefer the API of the first approach, but I have to strike that option because it's non-compliant. The second approach seems most semantically correct, but the API isn't very convenient: clients will have to deal with response headers, when most of the time they want to be able to do something easy like response.count. So I'm leaning toward the third approach, but I'm concerned about the potential problems involved with defining a new HTTP method.
What would you do?
The main purpose of rest is to define a set of resources that you interact with using well defined verbs. You must thus avoid to define your own verbs. The number of resources should be considered as a different resource, with its own uri that you can simply GET.
For example:
GET resources?crit1=val1&crit2=val2
returns the list of resources and
GET resources/count?crit1=val1&crit2=val2
Another option is to use the conneg: e.g. Accept: text/uri-list returns the resources list and Accept: text/plain returns only the count
You can use HEAD without breaking the HTTP specification and you can indicate the count by using an HTTP Range header in the response:
HEAD /resource/?search=lorem
Response from the service, assuming that you return the first 20 results by default:
...
Content-Range: resources 0-20/12345
...
This way you transfer the amount of resources to the client within the header of the response message without the need to return a message body.
Update:
The solution suggested Yannick Loiseau will work fine. Just wanted to provide one other alternative approach which can be used to achieve what you need without the need to define a new resource of verb.
You can use GET and add the count into the body of the message. Then, if you API allows clients to request a range of results, you can use that in order to limit the size of message body to a minimum (since you only want the count). One way to do that would be to request an empty range (from 0 to 0), for example:
GET /resource/?search=lorem&range=0,0
The service could then respond as follows, indicating that there are 1234 matching resources in the result set:
<?xml version="1.0" encoding="UTF-8" ?>
<resources range="0-0/1234" />
Ignoring the HTTP specification and returning the object count in the response body of a HEAD request.
IMHO, this is a very bad idea. It may not work simply because you might have intermediaries that don't ignore the HTTP spec.
Defining a new HTTP method, COUNT, that returns the object count in the response body.
There is no problem with this approach. HTTP is extendable and you can define your own verbs. Some firewalls prohibit this, but they are usually also prohibit POST and DELETE and X-HTTP-Method-Override header is widely supported.
Another option, to add a query param to your url, something like: ?countOnly=true
I need to invoke a process which doesn't require any input from the user, just a trigger. I plan to use POST /uri without a body to trigger the process. I want to know if this is considered bad from both HTTP and REST perspectives?
I asked this question on the IETF HTTP working group a few months ago. The short answer is: NO, it's not a bad practice (but I suggest reading the thread for more details).
Using a POST instead of a GET is perfectly reasonable, since it also instructs the server (and gateways along the way) not to return a cached response.
POST is completely OK. In difference of GET with POST you are changing the state of the system (most likely your trigger is "doing" something and changing data).
I used POST already without payload and it "feels" OK. One thing you should do when using POST without payload: Pass header Content-Length: 0. I remember problems with some proxies when I api-client didn't pass it.
If you use POST /uri without a body it is something like using a function which does not take an argument .e.g int post (void); so it is reasonable to have function to your resource class which can change the state of an object without having an argument. If you consider to implement the Unix touch function for a URI, is not it be good choice?
Yes, it's OK to send a POST request without a body and instead use query string parameters. But be careful if your parameters contain characters that are not HTTP valid you will have to encode them.
For example if you need to POST 'hello world' to and end point you would have to make it look like this: http://api.com?param=hello%20world
Support for the answers that POST is OK in this case is that in Python's case, the OpenAPI framework "FastAPI" generates a Swagger GUI (see image) that doesn't contain a Body section when a method (see example below) doesn't have a parameter to accept a body.
the method "post_disable_db" just accepts a path parameter "db_name" and doesn't have a 2nd parameter which would imply a mandatory body.
#router.post('/{db_name}/disable',
status_code=HTTP_200_OK,
response_model=ResponseSuccess,
summary='',
description=''
)
async def post_disable_db(db_name: str):
try:
response: ResponseSuccess = Handlers.databases_handler.post_change_db_enabled_state(db_name, False)
except HTTPException as e:
raise (e)
except Exception as e:
logger.exception(f'Changing state of DB to enabled=False failed due to: {e.__repr__()}')
raise HTTPException(HTTP_500_INTERNAL_SERVER_ERROR, detail=e.__repr__())
return response