How to POST json to https

Programming Questions

miked3

in Programming Questions • 2 years ago

Hi Everyone,

I'm trying to use the API for my online brokerage (OptionsHouse) and have gotten nowhere in the last 5 hours.
The API documentation says:
The OptionsHouse API is available through api.optionshouse.com. All requests must be sent
directly to api.optionshouse.com/j or api.optionshouse.com/m (specified below) via https
connections for security reasons. Requests should be POST requests with text/xml as content-
type...An API service has an expected JSON structure provided as input and will return a well-formed JSON structure as a result.

Here is their example json message for log-in:
{
"message":{
"action":"auth.login",
"data":{
"userName":"user1",
"password":"password",
}}

So far I've these forum threads and sites most helpful:
http://forum.processing.org/topic/http-post-processing
http://json.org/JSONRequest.html
http://data.oreilly.com/~aodewahn/processing_json/process_json.txt
http://blog.blprnt.com/blog/blprnt/processing-json-the-new-york-times (I wish the optionshouse api was this simple)

But I'm still very far from pulling things together. I am practicing using the Flickr API because I don't want to risk losing access to the optionshouse api due to mistakes in programming. If anyone knows a simple way of sending json format POST to https I'd greatly appreciate your help. Processing is really the only language I'm familiar with so all the Ajax jQuery and javascript stuff has me pounding my head against the wall.

Thanks,
Mike

Replies(7)

PhiLho

Re: How to POST json to https

2 years ago

I found back this thread just by typing https in the search field of the forum...
http://forum.processing.org/topic/data-from-password-protected-website
Maybe it can help you a bit.

miked3

Re: How to POST json to https

2 years ago

I ended up hiring a tutor to walk me through the java for this. Here is what I ended up with. It does work.

//Establish URL connection*************************************************************
URL url = new URL(baseUrl);
HttpURLConnection conn = null;
try {
    conn = (HttpURLConnection) url.openConnection();
    try {
      conn.setRequestMethod("POST"); //use post method
      conn.setDoOutput(true); //we will send stuff
      conn.setDoInput(true); //we want feedback
      conn.setUseCaches(false); //no caches
      conn.setAllowUserInteraction(false);
      conn.setRequestProperty("Content-Type","text/xml");
    }
    catch (ProtocolException e) {
    }

    // Open a stream which can write to the URL******************************************
    OutputStream out = conn.getOutputStream();
    try {
      OutputStreamWriter wr = new OutputStreamWriter(out);
      wr.write(ezm.toString()); //ezm is my JSON object containing the api commands
      wr.flush();
      wr.close();
    }
    catch (IOException e) {
    }
    finally { //in this case, we are ensured to close the output stream
      if (out != null)
        out.close();
    }

    // Open a stream which can read the server response*********************************
    InputStream in = conn.getInputStream();
    try {
      BufferedReader rd = new BufferedReader(new InputStreamReader(in));
      while ((responseSingle = rd.readLine()) != null) {
        response = response + responseSingle;
      }
      rd.close(); //close the reader
      //println("The server response is " + response);
    }
    catch (IOException e) {
    }
    finally { //in this case, we are ensured to close the input stream
      if (in != null)
        in.close();
    }
}
catch (IOException e) {
}
finally { //in this case, we are ensured to close the connection itself
    if (conn != null)
      conn.disconnect();
}
//Done communicating with server******************************************************

zimady

Re: How to POST json to https

2 years ago

@miked3 - firstly, thanks for posting the code. I'm trying to do much the same thing and floundering a little!

I've tried to implement your code but I think there are a couple of variable declarations missing?

I'm getting the following: Cannot find anything named "responseSingle"

Given you assign a String value to it, I've declared it as a String which solves it but then gives me: Cannot find anything named "response"

I assume that is also a String but the next line appends 'responseSingle' to 'response' and assigns the result back to 'response' so I am guessing 'response' should have had some value in the first place? I can't figure out what it should have been or where it was derived from.

Any help would be very much appreciated.

miked3

Re: Re: How to POST json to https

2 years ago

Hey,
Glad someone is getting use out of this.
I did leave out some declarations because they occur elsewhere in my overall program.
String responseSingle, response = "";
while ((responseSingle = rd.readLine()) != null) {
response = response + responseSingle;
response just starts out as empty. responseSingle is assigned by the .readline function, and they repeatedly appended to response until there is nothing left to read.

Hope that helps.

-mike

PhiLho

Re: How to POST json to https

2 years ago

Some remarks on the given code: it is better to close the enclosing IO structure, that automatically flush and close the enclosed ones. And it is better not to build a string like you do, it is inefficient.

StringBuilder response = new StringBuilder();
//Establish URL connection*************************************************************
URL url = new URL(baseUrl);
HttpURLConnection conn = null;
try {
conn = (HttpURLConnection) url.openConnection();
try {
conn.setRequestMethod("POST"); //use post method
conn.setDoOutput(true); //we will send stuff
conn.setDoInput(true); //we want feedback
conn.setUseCaches(false); //no caches
conn.setAllowUserInteraction(false);
conn.setRequestProperty("Content-Type","text/xml");
}
catch (ProtocolException e) {
}
// Open a stream which can write to the URL******************************************
OutputStream out = conn.getOutputStream();
OutputStreamWriter wr = null;
try {
wr = new OutputStreamWriter(out);
wr.write(ezm.toString()); //ezm is my JSON object containing the api commands
}
catch (IOException e) {
}
finally { //in this case, we are ensured to close the output stream
if (wr != null)
wr.close();
}
// Open a stream which can read the server response*********************************
InputStream in = conn.getInputStream();
BufferedReader rd = null;
try {
rd = new BufferedReader(new InputStreamReader(in));
String responseSingle = null;
while ((responseSingle = rd.readLine()) != null) {
response.append(responseSingle);
}
//println("The server response is " + response);
}
catch (IOException e) {
}
finally { //in this case, we are ensured to close the input stream
if (rd != null)
rd.close();
}
}
catch (IOException e) {
}
finally { //in this case, we are ensured to close the connection itself
if (conn != null)
conn.disconnect();
}
//Done communicating with server******************************************************

But you don't do HTTPS here, do you?
Anyway, thanks for sharing.

miked3

Re: Re: How to POST json to https

2 years ago

I'm sure there are lots of ways it could be improved. I'm not a computer scientist, this was just a project.
I think if the base url is https then you get an https connecton but I could be wrong.

zimady

Re: How to POST json to https

2 years ago

@miked3

Thanks for coming back on this one. I guessed it was exactly as you describe and got working :)

Thanks again, this snippet has helped me immensely.

@phi.lho

Thanks for the tip.

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