Sinatra allows the return values of route blocks to take many different forms.
How does Sinatra know how to extract status, headers, and body from each type of return value?
Particularly, I'm looking for the source code (logic) that does this, because I'd like to do something similar.
I've searched the Sinatra & Rack sources to no avail.
The code you’re looking for is in the invoke method:
def invoke
res = catch(:halt) { yield }
res = [res] if Fixnum === res or String === res
if Array === res and Fixnum === res.first
res = res.dup
status(res.shift)
body(res.pop)
headers(*res)
elsif res.respond_to? :each
body res
end
nil # avoid double setting the same response tuple twice
end
There are a couple of quirks to look out for. For example if you return a hash Sinatra will see that it responds to each and treat it as the body, but since it doesn’t yield strings this can cause an error or unexpected results when the webserver tries to send the content. Also the rack spec says this about the status: “When parsed as integer (to_i), it must be greater than or equal to 100” and so you should be able to pass a string like "200" that will be converted with to_i, but Sinatra only looks for Fixnums, which goes against its claim of “You can return any object that would either be a valid Rack response”.
Related
I have two end point.
-/authenticate
-/authenticate/verification
/authenticate return guid field on response body.
and /authenticate/verification requires that field on request body.
I have tried to get guid like this :
jsonPath("$..guid").saveAs("verificationGuid")
and pass it to other body :
.body(StringBody(s"{\"guid\":${verificationGuid}, \"code\":\"123456\"}"))
this is the code block:
def login = {
exec(http("Authenticate")
.post("/authenticate")
.body(StringBody(userString))
.headers(headerLogin)
.check(status is 200)
.check(jsonPath("$..guid").saveAs("verificationGuid"))
)
.exec(http( "Authenticate verify")
.post("/authenticate/verify")
.headers(headerLogin)
.body(StringBody(s"{\"guid\":${verificationGuid}, \"code\":\"123456\"}"))
.check(status is 200)
)
}
But it doesnt work, how can I do this?
Remove s from s"{\"guid\":${verificationGuid}, \"code\":\"123456\"}"). If s is in front of string every ${something} placeholder will be treated as Scala built in string interpolation and compiler will try to replace it with Scala variable, which in your case does not exist. Without s it will be treated as literal string and than caught by Gatling EL Parser and replaced with previously saved Gatling session attribute.
I'm using tornado and trying to get a facebook user's email address from the Graph API. I have the following code (most of which is from the Tornado website)
class FacebookAuth2Handler(BaseHandler,tornado.auth.FacebookGraphMixin):
#tornado.gen.coroutine
def get(self):
if self.get_argument("code", False):
user = yield self.get_authenticated_user(redirect_uri=self.settings["facebook_redirect_uri"],
client_id=self.settings["facebook_app_id"],
client_secret=self.settings["facebook_secret"],
code=self.get_argument("code"))
ob = yield self.facebook_request("/me/email",access_token=user["access_token"])
print(ob)
else:
yield self.authorize_redirect(redirect_uri=self.settings["facebook_redirect_uri"],
client_id=self.settings["facebook_app_id"],
extra_params={"scope": ["email","public_profile"]})
The problem seems to be fetching the /me/email with the facebook_request() this crashes with the following:
tornado.auth.AuthError: Error response HTTP 400: Bad Request fetching https://graph.facebook.com/me/email?access_token=xxxxxxx
Setting the path to "/me/email" is not valid, and setting it to "/me?fields=email" causes it to send your url as "/me?fields=email?access_token=xxxxxxx", which is no good either.
use the fields parameter:
ob = yield self.facebook_request(
path="/me",
access_token=user["access_token"],
fields="email,gender"
)
or you can really simplify things by adding the extra_fields parameter to get_authenticated_user. Note it is a python list, not a comma-separated string like above:
user = yield self.get_authenticated_user(redirect_uri=self.settings["facebook_redirect_uri"],
client_id=self.settings["facebook_app_id"],
client_secret=self.settings["facebook_secret"],
code=self.get_argument("code"),
extra_fields=['email','gender']
)
Any missing or unpermitted fields will show as None in the returned user mapping object.
is there a way to return a value inside Action controller.
I have a method in my User model which returns the number of friends of a given user.
def nrOfFriends(current_user: Long): Int = {
DB.withConnection{ implicit connection =>
var nr: Int = SQL("select count(*) from friend where user_id_1=" + current_user + " or user_id_2=" + current_user).as(scalar[Int].single)
nr
}
}
In my controller, I just want to return the value from the model
def freunde() = IsAuthenticated { username => _ =>
User.findByUsername(username).map { user =>
var nr: Int = Friend.nrOfFriends(user.id.get)
Ok(""+nr)
}.getOrElse(Forbidden)
}
But in the way that is written, it will print "empty string " concatenated with the number
If I replace Ok(""+nr) with Ok(nr) I receive the following error:
"Cannot write an instance of Int to HTTP response. Try to define a Writeable[Int]"
I need for my action to return a value so that I can pass the value from the action to header.views.html inside the navbar something like that
#Freund.freunde Friends
if you want your response to just be the value of nr you can simply call nr.toString:
def freunde() = IsAuthenticated { username => _ =>
User.findByUsername(username).map { user =>
var nr: Int = Friend.nrOfFriends(user.id.get)
Ok(nr.toString)
}.getOrElse(Forbidden)
}
The error you're getting makes reference to the fact that Int doesn't have an implicit Writeable[Int] in scope. So play doesn't know how display an Int in an http response.
You can add make Int writeable by putting this in scope:
implicit val intWriteable = play.api.http.Writeable[Int](_.toString.getBytes, None)
Then you would be able to just say:
Ok(nr)
without error.
However, it sounds like you just want the result of nrOfFriends inside an unrelated template. If that's the case, you should be using an Action at all. Instead just call your model function inside the template where you need the data.
#User.nrOfFriends(user.id) Friends
Of course you would need to pass in the user to the template as well.
You didn't post a full sample of all the code involved in what you are trying to accomplish so I think this is the best I can do for now. Perhaps try posting the base template that your <a> is in.
An important point is that Actions are for production an HTTP response, and not just plain data internally to the application.
An action of a controller handles a request and generates a result to be sent to the client. In other words, an action returns a play.api.mvc.Result value, representing the HTTP response to send to the web client. In your example Ok constructs a 200 OK response. The body of the response must be one of the predefined types, including text/plain, json, and html. The number of a friends is an integer and is NOT an acceptable type of the body. Therefore, a simple way to address this problem is to convert it into a text/plain using .toString().
On the other hand, you can define a writer for Int that lets Play know how to convert an integer into a json format.
For more details, please take a look at this https://www.playframework.com/documentation/2.2.x/ScalaActions.
I am having some trouble with PUT requests to the google sheets api.
I have this code
spreadsheet_inputer := WebClient(`$google_sheet_URI_cells/R3C6?access_token=$accesstoken`)
xml_test := XDoc{
XElem("entry")
{
addAttr("xmlns","http://www.w3.org/2005/Atom")
addAttr("xmlns:gs","http://schemas.google.com/spreadsheets/2006")
XElem("id") { XText("https://spreadsheets.google.com/feeds/cells/$spreadsheet_id/1/private/full/R3C6?access_token=$accesstoken"), },
XElem("link") { addAttr("rel","edit");addAttr("type","application/atom+xml");addAttr("href","https://spreadsheets.google.com/feeds/cells/$spreadsheet_id/1/private/full/R3C6?access_token=$accesstoken"); },
XElem("gs:cell") { addAttr("row","3");addAttr("col","6");addAttr("inputValue","testing 123"); },
},
}
spreadsheet_inputer.reqHeaders["If-match"] = "*"
spreadsheet_inputer.reqHeaders["Content-Type"] = "application/atom+xml"
spreadsheet_inputer.reqMethod = "PUT"
spreadsheet_inputer.writeReq
spreadsheet_inputer.reqOut.writeXml(xml_test.writeToStr).close
echo(spreadsheet_inputer.resStr)
Right now it returns
sys::IOErr: No input stream for response 0
at the echo statement.
I have all the necessary data (at least i'm pretty sure) and it works here https://developers.google.com/oauthplayground/
Just to note, it does not accurately update the calendars.
EDIT: I had it return the response code and it was a 0, any pointers on what this means from the google sheets api? Or the fantom webclient?
WebClient.resCode is a non-nullable Int so it is 0 by default hence the problem would be either the request not being sent or the response not being read.
As you are obviously writing the request, the problem should the latter. Try calling WebClient.readRes() before resStr.
This readRes()
Read the response status line and response headers. This method may be called after the request has been written via writeReq and reqOut. Once this method completes the response status and headers are available. If there is a response body, it is available for reading via resIn. Throw IOErr if there is a network or protocol error. Return this.
Try this:
echo(spreadsheet_inputer.readRes.resStr)
I suspect the following line will also cause you problems:
spreadsheet_inputer.reqOut.writeXml(xml_test.writeToStr).close
becasue writeXml() escapes the string to be XML safe, whereas you'll want to just print the string. Try this:
spreadsheet_inputer.reqOut.writeChars(xml_test.writeToStr).close
I am attempting to retrieve the sizes various websites whose URL will be passed to my script, but I'm not getting an exception when I pass an invalid URL, instead simply getting a very small page. I'm using Source.fromURL, and I get the following results:
thisIsClearlyABoggusURLThatCantPossiblyLeadAnyway 1052
www.bbc.co.uk 113871
The first one, as it says, shouldn't have anything in it, but it does. My script is as follows:
def main( args:Array[String] ){
val tasks = for(arg <- args) yield future {
try {
println(arg + " " + Source.fromURL( attachPrefix(arg) ).length)
} catch {
case e : java.net.UnknownHostException => println(arg + " *")
}
}
awaitAll(20000L, tasks: _*)
}
def attachPrefix( url:String ) = url.slice(0, 4) match {
case "http" => url
case "www." => "http://" + url
case _ => "http://www." + url
}
Each argument is being passed into the function attachPrefix to ensure it has the necessary prefix before being used. This problem has only come about since I started passing the url in as a parameter instead of mapping it onto the arg, which is what I was doing earlier with
args map attachPrefix
What's the difference between the two, and why is my current one giving such behaviour?
You can use the Source.fromURL(URI) signature. Creating a URI will effectively validate the URL as documented here. However, in this case, the URL http://www.thisIsClearlyABoggusURLThatCantPossiblyLeadAnyway is valid as far as the URI is concerned. On the other hand, the UrlValidator suggested by om-nom-nom considers it invalid, because the top level domain segment has more than 4 characters which is already out of date. I don't know of any entirely Scala validation libraries or why this would be a requirement, but you could try using a regular expression for validation. For example, this will catch your example, because the top level domain exceeds 6 letters:
val re = """^(https?://)?(([\w!~*'().&=+$%-]+: )?[\w!~*'().&=+$%-]+#)?(([0-9]{1,3}\.){3}[0-9]{1,3}|([\w!~*'()-]+\.)*([\w^-][\w-]{0,61})?[\w]\.[a-z]{2,6})(:[0-9]{1,4})?((/*)|(/+[\w!~*'().;?:#&=+$,%#-]+)+/*)$""".r
re.pattern.matcher("http://google.com").matches // true
re.pattern.matcher("http://www.thisIsClearlyABoggusURLThatCantPossiblyLeadAnyway").matches // false