I've got a working local website that takes in HTML form data.
The fields are:
Temperature
Humidity
The server successfully receives the data and spits out a graph updated with the new entries.
Using a browser tool, I was able to capture the actual POST request as follows:
http://127.0.0.1:5000/add_data
Temperature=25.4&Humidity=52.2
Content-Length:30
Now, I want to migrate from using the human interface browser with manual entries to an ESP01 device using AT commands.
According to the ESP AT-commands documentation, a POST request is performed using the following command:
AT+HTTPCPOST=
Find the link below for the full description of the command.
I cannot seem to get this POST request working. The ESP01 device immediately returns an "ERROR" message without any delay, as though it did not even try to send the request, that the syntax might be wrong.
Among many variations, the following is my best attempt:
AT+HTTPCPOST="http://MYIPADDR:5000/add_data",30,2,"Temperature: 25.4","Humidity: 52.2"
With MYIPADDR above replaced with my IP address.
How do I translate a post request into ESP01 AT command format, and are there any prerequisites needed to be in place to perform such a request?
I did connect the ESP01 device to the WiFi network.
Here's the link to the POST AT command description:
https://docs.espressif.com/projects/esp-at/en/release-v2.2.0.0_esp8266/AT_Command_Set/HTTP_AT_Commands.html#cmd-httpcpost
The documentation says:
AT+HTTPCPOST=url,length[,<http_req_header_cnt>][,<http_req_header>..<http_req_header>]
Response:
OK
The symbol > indicates that AT is ready for receiving serial data, and you can enter the data now. When the requirement of message length
determined by the parameter is met, the transmission starts.
...
Parameters
: HTTP URL. : HTTP data length to POST. The maximum
length is equal to the system allocable heap size.
<http_req_header_cnt>: the number of <http_req_header> parameters.
[<http_req_header>]: you can send more than one request header to the
server.
You're sending:
AT+HTTPCPOST="http://MYIPADDR:5000/add_data",30,2,"Temperature: 25.4","Humidity: 52.2"
The length is 30. The problem is that everything after the length is HTTP header fields; you need to send the variables in the body. So the command is:
AT+HTTPCPOST="http://MYIPADDR:5000/add_data",30
followed on the next line by after the ESP-01 send the > character:
Temperature=25.4&Humidity=52.2
Because you passed 30 as the body length, the ESP-01 will read exactly 30 characters after the end of the AT command and send that data as the post body. If the size of that data changes (for instance, maybe the temperature is 2.2, so one digit less), you'll need to send the new length rather than 30.
Related
I'm currently using the PlayWS http client which returns an Akka stream. From my understanding, I can consume the stream and turn it into a Byte[] to calculate the size. However, this also consumes the stream and I can't use it anymore. Anyway around this?
I think there are two different aspects related to the question.
You want to know the size of the server response in advance to prepare buffer. Unfortunately there is no guaranteed way to do this. HTTP 1.1 spec explicitly allows transfer mode when the server does not know the size of the response in advance via chunked transfer encoding. See also quote from 3.3.1. Transfer-Encoding:
A recipient MUST be able to parse the chunked transfer coding
(Section 4.1) because it plays a crucial role in framing messages
when the payload body size is not known in advance.
Section 3.3.3. Message Body Length specifies how length of a message body is defined and it besides the aforementioned chunked transfer encoding it also contains quite unhelpful
Otherwise, this is a response message without a declared message
body length, so the message body length is determined by the
number of octets received prior to the server closing the
connection.
This is added for backward compatibility and discouraged from usage but is still legally allowed.
Still in many real world scenarios you can use Content-Length header field that the server may return. However there is a catch here as well: if gzip Content-Encoding is used, then Content-Length will contain size of the compressed body.
To sum up: in general case you can't get the size of the message body in advance before you fully get the server response i.e. in terms of code perform a blocking call on the response. You may try to use Content-Length and it might or might not help in your specific case.
You already have a fully downloaded response (or you are OK with blocking on your StreamedResponse) and you want to process it by first getting the size and only then processing the actual data. In such case you may first use getBodyAsBytes method which returns IndexedSeq[Byte] and thus has size, and then convert it into a new Source using Source.single which is actually exactly what the default (i.e. non-streaming) implementation of getBodyAsSource does.
For example, below is the JSON request data to "add a device" in the DB.
For example, I want to add 10000 devices with different IMEI number and different phone number to the server for testing purpose. So, how to send the request at once.
I'm ready to create 10000 devices data with different values manually.
Now I can able to send one by one only.But how to send all the request at once?
{
"device_name":"34793812453274392",
"imei_num":"36xxxxxxxxxxxx5",
"phone_num":"8666606451",
"device_city":"Chennai",
"device_state":"Tamil Nadu",
}
As I'm new to POSTMAN, required detailed info. Thanks in advance.
The thing that should work is :
you prepare your input JSon body with variables. ie, from your example :
{ "device_name":{{device_name}}, "imei_num":{{imei_num}}, "phone_num":{{phone_num}}, "device_city":{{device_city}}, "device_state":{{device_state}}, }
the {{}} is for variables
You create a CSV file with the corresponding headers (one for each variable of your input JSON) and all the values you need:
example:
line 1 : device_name, imei_num, phone_num, device_city, device_state
line 2 : "34793812453274392", "36xxxxxxxxxxxx5", "8666606451", "Chennai", "Tamil Nadu"
... and so on ...
line 10000 : ...
Then, in the Postman runner (see here ), you select the data file (Data / Select file) with CSV type (you should have an option to check the content, but be careful as you'll have a lots of rows, it may take a long time, I suggest you try first with a small CSV file)
You just set ONE iteration (otherwise you'll play x times 10000 requests).
It will parse your file and, for each data line, it will send your request with replacing the body's variables by the corresponding data associated to the corresponding header. Header names must have the same label as your variables.
Launching the runner will launch your 10000 requests sequentially
If you prefer, you can use JSON input file as data file, see here
Don't hesitate to have a look at postman documentation, it's pretty complete.
There is an option called Runner at the top left corner of your Postman application. You can select the collection you need to run with number of iterations and delay time between each request. But the thing is you cannot alter the values inside the JSON request. Thanks
Put all the data into a JSON Array
and then do them all as one post. Currently you only have one set of data you're posting in.
Just create a json body with all the data you need to enter and post them into the same API endpoint.
I am looking into the Swift Vapor framework.
I am trying to create a controller class that maps data obtained on an SSL link to a third party system (an Asterisk PBX server..) into a response body that is sent over some time down to the client.
So I need to send received text lines (obtained separately on the SSL connection) as they get in, without waiting for a 'complete response' to be constructed.
Seeing this example:
return Response(status: .ok) { chunker in
for name in ["joe\n", "pam\n", "cheryl\n"] {
sleep(1)
try chunker.send(name)
}
try chunker.close()
}
I thought it might be the way to go.
But what I see connecting to the Vapor server is that the REST call waits for the loop to complete, before the three lines are received as result.
How can I obtain to have try chunker.send(name) send it's characters back the client without first waiting for the loop to complete?
In the real code the controller method can potentially keep an HTTP connection to the client open for a long time, sending Asterisk activity data to the client as soon as it is obtained. So each .send(name) should actually pass immediately data to the client, not waiting for the final .close() call.
Adding a try chunker.flush() did not produce any better result..
HTTP requests aren't really designed to work like that. Different browsers and clients will function differently depending on their implementations.
For instance, if you connect with telnet to the chunker example you pasted, you will see the data is sent every second. But Safari on the other hand will wait for the entire response before displaying.
If you want to send chunked data like this reliably, you should use a protocol like WebSockets that is designed for it.
I want some level of real-time speech to text conversion. I am using the web-sockets interface with interim_results=true. However, I am receiving results for the first audio chunk only. The second,third... audio chunks that I am sending are not getting transcribed. I do know that my receiver is not blocked since I do receive the inactivity message.
json {"error": "Session timed out due to inactivity after 30 seconds."}
Please let me know if I am missing something if I need to provide more contextual information.
Just for reference this is my init json.
{
"action": "start",
"content-type":"audio/wav",
"interim_results": true,
"continuous": true,
"inactivity_timeout": 10
}
In the result that I get for the first audio chunk, the final json field is always received as false.
Also, I am using golang but that should not really matter.
EDIT:
Consider the following pseudo log
localhost-server receives first 4 seconds of binary data #lets say Binary 1
Binary 1 is sent to Watson
{interim_result_1 for first chunk}
{interim_result_2 for first chunk}
localhost-server receives last 4 seconds of binary data #lets say Binary 2
Binary 2 is sent to Watson
Send {"action": "stop"} to Watson
{interim_result_3 for first chunk}
final result for the first chunk
I am not receiving any transcription for the second chunk
Link to code
You are getting the time-out message because the service waits for you to either send more audio or send a message signalling the end of an audio submission. Are you sending that message? It's very easy:
By sending a JSON text message with the action key set to the value stop: {"action": "stop"}
By sending an empty binary message
https://www.ibm.com/smarterplanet/us/en/ibmwatson/developercloud/doc/speech-to-text/websockets.shtml
Please let me know if this does not resolve your problem
This is a bit late, but I've open-sourced a Go SDK for Watson services here:
https://github.com/liviosoares/go-watson-sdk
There is some documentation about speech-to-text binding here:
https://godoc.org/github.com/liviosoares/go-watson-sdk/watson/speech_to_text
There is also an example of streaming data to the API in the _test.go file:
https://github.com/liviosoares/go-watson-sdk/blob/master/watson/speech_to_text/speech_to_text_test.go
Perhaps this can help you.
The solution to this question was to set the size header of the wav file to 0.
I need to access the Date: header when I handle the request, but this seems to be "swallowed" by the framework; any other header (even made up FooBar ones) show up and I can get them, but this gives me None (I'm using Postman to send a simple GET request - everything else works just fine):
println("Date: " + request.headers.get("Date").getOrElse("no date!"))
returns "no date!" no matter how I try to send something sensible.
I'm wondering whether this gets processed before the request object reaches my Action.
I need the actual string value sent, as this should be part of the request's signature - so an equivalent Date object representing the same value would not be of much use (as it needs to be part of the hash, to avoid replay attacks).
Just as a test, I replaced the Date header with a Date-Auth one, and this one shows up just fine:
ArrayBuffer((Date-Auth, ArrayBuffer(Wed, 15 Nov 2014 06:25:24 GMT))
Any ideas or suggestions greatly appreciated!
Are you sure there is a Date Header in your request (tested with tools like firebug or wireshark)?
Browsers do not need to send a Date header.
RFC 2616 (HTTP 1.1) from the Date section (14.18)
Clients SHOULD only send a Date header field in messages that include an entity-body, as in the case of the PUT and POST requests, and even then it is optional. A client without a clock MUST NOT send a Date header field in a request.
I stand corrected - it turns out that Chrome blocks a whole bunch of headers:
http://www.getpostman.com/docs/requests
I wrote a Python Flask test server and, in fact, the Date header is not there.
That page has also a fix, which works just fine with Postman Version 0.10.4.3 and Interceptor(1).
sorry for wasting everyone's time!
1 Incidentally, IMO Postman is the best REST client and has now also some awesome looks, beyond incredible functionality. If you're working with REST APIs, I highly recommend it.