File content as of revision 4:33006c37c633:

#include "plotly.h"
#include "mbed.h"

#define plotlyURL "plot.ly"
#define dataURL "arduino.plot.ly"

plotly::plotly(char *username, char *api_key, char* stream_token, char *filename)
{
    log_level = 3;  // 0 = Debugging, 1 = Informational, 2 = Status, 3 = Errors, 4 = Quiet (// Serial Off)
    dry_run = false;
    username_ = username;
    api_key_ = api_key;
    stream_token_ = stream_token;
    filename_ = filename;
    maxpoints = 30;
    world_readable = true;
    convertTimestamp = false;
    timezone = "America/Montreal";
    fileopt = "overwrite";

    socket = NULL;

    initalised = false;
}


plotly::~plotly()
{
    closeStream();

}


bool plotly::init()
{

    //
    //  Create plot with a REST post to plotly
    //  See the clientresp section of https://plot.ly/rest/ for details
    //
    if(dry_run && log_level < 3) {
        fprintf(stderr,"... This is a dry run, we are not connecting to plotly's servers...\n");
    } else if(log_level < 3) {
        fprintf(stderr,"... Attempting to connect to plotly's REST servers\n");
    }

    if (!dry_run) {
        int pause = 1;
        socket = new TCPSocketConnection();
        while (socket->connect(plotlyURL, 80) < 0) {
            if (pause > 30) {
                fprintf(stderr,"Failed to connect. :-(\n");
                delete socket;
                return false;
            }
            fprintf(stderr,"... Couldn\'t connect to plotly's REST servers... trying again!\n");
            wait(pause);
            pause *= 2;
        }
    }

    if(log_level < 3) fprintf(stderr,"... Connected to plotly's REST servers\n");

    if(log_level < 3) fprintf(stderr,"... Sending HTTP Post to plotly\n");

    print_("POST /clientresp HTTP/1.1\r\n");
    print_("Host: 107.21.214.199\r\n");
    print_("User-Agent: Arduino/0.5.1\r\n");
    print_("plotly-streamtoken: ");
    print_(stream_token_);
    printNetTerminator_();

    print_("Content-Length: ");

    // calculate the length of the packet payload and store it in the big buffer.
    int lineLen = snprintf(buffer,k_bufferSize,"version=2.3&origin=plot&platform=arduino&un=%s&key=%s&args=[",username_,api_key_);
    lineLen += snprintf((buffer+lineLen),k_bufferSize-lineLen,"{\"y\": [], \"x\": [], \"type\": \"scatter\", \"stream\": {\"token\": \"%s\", \"maxpoints\": %d}}",stream_token_,maxpoints);
    lineLen += snprintf((buffer+lineLen),k_bufferSize-lineLen,"]&kwargs={\"fileopt\": \"%s\", \"filename\": \"%s\", \"world_readable\": %s}",fileopt,filename_,world_readable?"true":"false");

    print_(lineLen);

    printNetTerminator_();
    printNetTerminator_();

    sendFormatedText(buffer,lineLen);

    printNetTerminator_();

    //
    // Wait for a response
    // Parse the response for the "All Streams Go!" and proceed to streaming
    // if we find it
    //

    char allStreamsGo[] = "All Streams Go!";
    int asgCnt = 0; // asg stands for All Streams Go
    char url[] = "\"url\": \"http://107.21.214.199/~";
    char fid[4];
    int fidCnt = 0;
    int urlCnt = 0;
    int usernameCnt = 0;
    bool proceed = false;
    bool fidMatched = false;
    char c;

    if(log_level < 2) {
        fprintf(stderr,"... Sent message, waiting for plotly's response...\n");
    }

    if(!dry_run) {
        while(!proceed) {
            int32_t dataIn = socket->receive(buffer,k_bufferSize -1);
            if (dataIn < 0) {
                if(log_level < 3) fprintf(stderr,"error reading network socket\n");
                break;
            }
            if(dataIn > 0) {
                buffer[dataIn]=0;

                if(log_level < 2) fprintf(stderr,buffer);

                for (int i = 0; i<dataIn; i++) {
                    c = buffer[i];
                    //
                    // Attempt to read the "All streams go" msg if it exists
                    // by comparing characters as they roll in
                    //

                    if(asgCnt == strlen(allStreamsGo) && !proceed) {
                        proceed = true;
                    } else if(allStreamsGo[asgCnt]==c) {
                        asgCnt += 1;
                    } else if(asgCnt > 0) {
                        // reset counter
                        asgCnt = 0;
                    }

                    //
                    // Extract the last bit of the URL from the response
                    // The url is in the form http://107.21.214.199/~USERNAME/FID
                    // We'll character-count up through char url[] and through username_, then start
                    // filling in characters into fid
                    //

                    if(log_level < 3) {
                        if(url[urlCnt]==c && urlCnt < strlen(url)) {
                            urlCnt += 1;
                        } else if(urlCnt > 0 && urlCnt < strlen(url)) {
                            // Reset counter
                            urlCnt = 0;
                        }
                        if(urlCnt == strlen(url) && fidCnt < 4 && !fidMatched) {
                            // We've counted through the url, start counting through the username
                            if(usernameCnt < strlen(username_)+2) {
                                usernameCnt += 1;
                            } else {
                                // the url ends with "
                                if(c != '"') {
                                    fid[fidCnt] = c;
                                    fidCnt += 1;
                                } else if(fidCnt>0) {
                                    fidMatched = true;
                                }

                            }
                        }
                    }
                }
            }
            wait(0.1);
        }
    }

    if(!dry_run && !proceed && log_level < 4) {
        fprintf(stderr,"... Error initializing stream, aborting. Try again or get in touch with Chris at chris@plot.ly\n");
    }

    if(!dry_run && proceed && log_level < 3) {
        fprintf(stderr,"... A-ok from plotly, All Streams Go!\n");
        if(fidMatched) {
            fprintf(stderr,"... View your streaming plot here: https://plot.ly/~");
            fprintf(stderr,username_);
            fprintf(stderr,"/");
            for(int i=0; i<fidCnt; i++) {
                fprintf(stderr,"%c",fid[i]);
            }
            fprintf(stderr,"\n");
        }
    }

    if (proceed || dry_run) {
        initalised = true;
    }
    if (socket) {
        delete socket;
        socket=NULL;
    }
    return initalised;
}

bool plotly::openStream()
{

    if (!initalised)
        return false;

    //
    // Start request to stream servers
    //

    if (socket) {
        delete socket;
        socket = NULL;
    }


    if(log_level < 3) fprintf(stderr,"... Connecting to plotly's streaming servers...\n");


    if (!dry_run) {
        int pause = 1;
        socket = new TCPSocketConnection();
        while (socket->connect(dataURL, 80) < 0) {
            if (pause > 30) {
                fprintf(stderr,"Failed to connect. :-(\n");
                delete socket;
                return false;
            }
            fprintf(stderr,"... Couldn\'t connect to plotly's REST servers... trying again!\n");
            wait(pause);
            pause *= 2;
        }
    }


    if(log_level < 3) fprintf(stderr,"... Connected to plotly's streaming servers\n... Initializing stream\n");

    print_("POST / HTTP/1.1\r\n");
    print_("Host: arduino.plot.ly\r\n");
    print_("User-Agent: Python\r\n");
    print_("Transfer-Encoding: chunked\r\n");
    print_("Connection: close\r\n");
    print_("plotly-streamtoken: ");
    print_(stream_token_);
    printNetTerminator_();
    if(convertTimestamp) {
        print_("plotly-convertTimestamp: \"");
        print_(timezone);
        print_("\"");
        printNetTerminator_();
    }
    printNetTerminator_();

    if(log_level < 3) fprintf(stderr,"... Done initializing, ready to stream!\n");
    return true;
}

void plotly::closeStream()
{
    if (socket) {
        if (socket->is_connected()) {
            print_("0\r\n\r\n");
            socket->close();
        }
        delete socket;
        socket=NULL;
    }
}

void plotly::reconnectStream()
{
    while(!dry_run && (!socket || !socket->is_connected())) {
        if(log_level<4) fprintf(stderr,"... Disconnected from streaming servers\n");
        closeStream();
        openStream();
    }
}

void plotly::plot(unsigned long x, int y)
{
    if (!initalised)
        return;

    reconnectStream();

    // need to prefix with the length so print it once to get the content lenght and then a second time with the prefix.
    int len = snprintf(buffer,k_bufferSize,"{\"x\": %lu, \"y\": %d}\n", x,y);
    len = snprintf(buffer,k_bufferSize,"%x\r\n{\"x\": %lu, \"y\": %d}\n\r\n",len, x,y);
    sendFormatedText(buffer,len);
}

void plotly::plot(unsigned long x, float y)
{
    if (!initalised)
        return;

    reconnectStream();

    // need to prefix with the length so print it once to get the content lenght and then a second time with the prefix.
    int len = snprintf(buffer,k_bufferSize,"{\"x\": %lu, \"y\": %.3f}\n", x,y);
    len = snprintf(buffer,k_bufferSize,"%x\r\n{\"x\": %lu, \"y\": %.3f}\n\r\n",len, x,y);
    sendFormatedText(buffer,len);
}

bool plotly::print_(int d)
{
    char smallBuffer[10];
    int32_t len = snprintf(smallBuffer,10,"%d",d);
    return sendFormatedText(smallBuffer,len);
}

bool plotly::print_(unsigned long d)
{
    char smallBuffer[12];
    int32_t len = snprintf(smallBuffer,12,"%lu",d);
    return sendFormatedText(smallBuffer,len);
}

bool plotly::print_(float d)
{
    char smallBuffer[12];
    int32_t len = snprintf(smallBuffer,12,"%f",d);
    return sendFormatedText(smallBuffer,len);
}

bool plotly::printNetTerminator_()
{
    return sendFormatedText("\r\n",2);
}


bool plotly::print_(char *d) // strings could be long, use the big buffer
{
    int32_t len = snprintf(buffer,k_bufferSize,"%s",d);
    return sendFormatedText(buffer,len);
}


bool plotly::sendFormatedText(char* data, int size)
{
    if(log_level < 2) {
        fprintf(stderr,"%s",data);
    }
    if(!dry_run) {
        if (!socket) {
            fprintf(stderr,"\nTX failed, No network socket exists\n");
            return false;
        }
        if (!(socket->is_connected())) {
            fprintf(stderr,"\nTX failed, Network socket not connected\n");
            return false;
        }

        int32_t sent = socket->send_all(data,size);
        if (sent == size)
            return true;
        else {
            fprintf(stderr,"\nTX failed to send _%s_ Sent %d of %d bytes\n",data,sent,size);
            return false;
        }
    } else
        return true;
}