I'm building a custom dynamicValue extension for paw. However i'm not able to set header in the evaluate method. See the sample code below:
evaluate(context) {
const request = context.getCurrentRequest();
request.setHeader('Content-Type', this.contentType); // <-- this gives warning
return this.createSignable(request); // This returns a base64 string.
}
I get the warning saying Javascript extension error: Cannot perform modifications and the header is not set. ( when i comment out request.setHeader call, i get no warnings)
Can anyone please help me resolve this issue?
This is correct, you cannot use setters (set any value) in a dynamic value. In fact, the way Paw evaluates dynamic values is asynchronous and as multiple evaluations can take place simultaneously it would be impossible to record the modifications. For this reason, Paw is simply denying changes and no change is persisted during evaluation.
In the documentation, it's specified that these methods (like setHeaders) is only available for importer extensions. Sorry for the inconvenience!
I think to achieve what you're trying to do, you would need two dynamic values one set in the Authorization header and one set in the Content-Type header.
Alternatively, in the future we're going to add request post-processors, so you'll be able to mutate the computed request ready to be sent to the server for additional modifications.
Related
I need to reuse value which is generated for my previous request.
For example, at first request, I make a POST to the URL /api/products/{UUID} and get HTTP response with code 201 (Created) with an empty body.
And at second request I want to get that product by request GET /api/products/{UUID}, where UUID should be from the first request.
So, the question is how to store that UUID between requests and reuse it?
You can use the Request Sent Dynamic values https://paw.cloud/extensions?extension_type=dynamic_value&q=request+send these will get the value used last time you sent a requst for a given request.
In your case you will want to combine the URLSentValue with the RegExMatch (https://paw.cloud/extensions/RegExMatch) to first get the url as it was last sent for a request and then extract the UUID from the url.
e.g
REQUEST A)
REQUEST B)
The problem is in your first requests answer. Just dont return "[...] an empty body."
If you are talking about a REST design, you will return the UUID in the first request and the client will use it in his second call: GET /api/products/{UUID}
The basic idea behind REST is, that the server doesn't store any informations about previous requests and is "stateless".
I would also adjust your first query. In general the server should generate the UUID and return it (maybe you have reasons to break that, then please excuse me). Your server has (at least sometimes) a better random generator and you can avoid conflicts. So you would usually design it like this:
CLIENT: POST /api/products/ -> Server returns: 201 {product_id: UUID(1234...)}
Client: GET /api/products/{UUID} -> Server returns: 200 {product_detail1: ..., product_detail2: ...}
If your client "loses" the informations and you want him to be later able to get his products, you would usually implement an API endpoint like this:
Client: GET /api/products/ -> Server returns: 200 [{id:UUID(1234...), title:...}, {id:UUID(5678...),, title:...}]
Given something like this, presuming the {UUID} is your replacement "variable":
It is probably so simple it escaped you. All you need to do is create a text file, say UUID.txt:
(with sample data say "12345678U910" as text in the file)
Then all you need to do is replace the {UUID} in the URL with a dynamic token for a file. Delete the {UUID} portion, then right click in the URL line where it was and select
Add Dynamic Value -> File -> File Content :
You will get a drag-n-drop reception widget:
Either press the "Choose File..." or drop the file into the receiver widget:
Don't worry that the dynamic variable token (blue thing in URL) doesn't change yet... Then click elsewhere to let the drop receiver go away and you will have exactly what you want, a variable you can use across URLs or anywhere else for that matter (header fields, form fields, body, etc):
Paw is a great tool that goes asymptotic to awesome when you explore the dynamic value capability. The most powerful yet I have found is the regular expression parsing that can parse raw reply HTML and capture anything you want for the next request... For example, if you UUID came from some user input and was ingested into the server, then returned in a html reply, you could capture that from the reply HTML and re-inject it to the URL, or any field or even add it to the cookies using the Dynamic Value capabilities of Paw.
#chickahoona's answer touches on the more normal way of doing it, with the first request posting to an endpoint without a UUID and the server returning it. With that in place then you can use the RegExpMatch extension to extract the value from the servers's response and use it in subsequent requests.
Alternately, if you must generate the UUID on the client side, then again the RegExpMatch extension can help, simply choose the create request's url for the source and provide a regexp that will strip the UUID off the end of it, such as /([^/]+)$.
A third option I'll throw out to you, put the UUID in an environment variable and just have all of your requests reference it from there.
I am writing a new endpoint in my HTTP service that is built on the Play framework, and am returning a custom status code for a particular error (442 in this case). When I test the endpoint with cURL, I receive the error code as expected:
...
< HTTP/1.1 442 Client Error (442)
....
And the same with Postman REST Client:
What I would like to do is customize the "Client Error" text, such that the response would actually read something like:
442 Forced Password Reset
Is this possible, or is it in the spec somewhere that any custom status codes of the 4xx class are to be interpreted by all clients simply as "Client Error"?
(I have been looking through the relevant Play documentation on Statuses but don't see any option to customize the text—only the status code integer itself.)
Looking through the source code it didn't take me long to find the following:
Play just stores the status code in the RepsonseHeader, not the string
Play uses Netty, and turns the status code into a HttpResponseStatus using valueOf, which is basically just a case statement over the status codes, with defaults based on the range if it isn't standard.
Although you could define a new Netty HttpResponseStatus with the reason phrase you want, there isn't any way to add it to the valueOf method (it's static).
So, there isn't any really good solution without rewriting some parts of Play!.
You might be able to use some sort of post-filter to modify the response and change the reason phrase, but I don't know how that would work, or even if it is possible to write those kinds of filters in Play!.
Finally, the reason phrase isn't really that important, as clients generally don't (and shouldn't) actually parse it.
I did create a simple testcase in JMeter.
Open a form and all it's content (css, images etc) :
GET /
GET /css/site.css
GET /favicon.ico
GET /fonts/specific-fonts.woff
GET /images/banner.png
Wait a little...
Post the values
POST /
Receive the "Thank You" page.
- GET /thanks
In the response on the first GET is a hidden input field which contains a token. This token needs to be included in the POST as well.
Now I use the "Regular Expression Extractor" of JMeter to get the token from the response. So far, so good.
Then, after retreiving all the other contents I create the POST message, using the variable name in the RegExp-Extractor in the value field of the token parameter.
But... when executing the testcase it fills in the default value given and not the actual value of the token.
So... first step in debugging this issue was to add a dummy-HTTP-GET request directly after I get the token. In this GET request I also add the token parameter with the token variable as value, but now I can easily check the parameter by looking at the access-log on my webserver.
In this case... the URL looks promising. It contains the actual token value in the GET, but it still uses the default value in the POST.
Second step in debugging was to use the "Debug Sampler" and the "View Results Tree".
By moving the Debug Sampler between the different steps I found out the value of the token-variable is back to the default value after I receive the CSS.
So... now the big question is...
How can I make JMeter to remember my variable value until the end of my test-script ?
JMeter doesn't "forget" variables. However variables scope is limited to the current Thread Group. You can convert JMeter variable to JMeter Property which have "global" scope by i.e. using Beanshell Post Processor with the following code:
props.put("myVar", vars.get("myVar"));
Or by using __setProperty() function. See How to Use Variables in Different Thread Groups guide for details.
As you found it your problem comes from a misunderstanding of scoping rules in jmeter.
https://jmeter.apache.org/usermanual/test_plan.html#scoping_rules
In your case, just put the post processor of the request that will give you the response containing the child node.
Also I think you don't need to share this token with other threads so don't use properties as proposed in the alternate answer.
I have a batch of requests in Fiddler, the first is a login request and returns a valid cookie. The rest need to use this cookie, I know I can break and edit headers but is it possible to automatically script this behaviour? I'm pretty new to Fiddler but it looks powerful so I'm hoping this is possible, anyone know how or where to start?
To manually add a header, use the Filters tab and use the Request Headers section.
To automatically add a header, click Rules > Customize Rules. Scroll to OnBeforeResponse and write code that stores the target cookie in a global variable declared just inside the Handlers function, e.g.
static var m_MyCookie: String;
Then, inside the OnBeforeRequest function, use that variable, e.g.
if (!String.IsNullOrEmpty(m_MyCookie)) oSession.oRequest["Cookie"] = (m_MyCookie + ";" + oSession.oRequest["Cookie"] )
If you're only trying to add this header to specific requests, use, for instance, the oSession.uriContains function to determine whether the target URL is one that you want to have the cookie.
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