source: gs3-extensions/meandre/trunk/src/web/meandre-controller.js@ 28547

// Examples of how to control a Meandre Infrastructure (running on default port of 1714)

//  http://localhost:1714/services/execute/flow.txt?statistics=true&uri=http://greenstone.org/meandre/flows/chromagram-v3/&token=abc
//    => Runs the specified flow, 
//    => gives the Infrastructure a token to identify the given running instance

//  http://localhost:1714/services/execute/uri_flow.txt?statistics=true&token=abc
//    => Uses the 'token' to glean values of the running instance, such as which port it is using
//    => Reponse is plain text in value-pair form of properties


//  http://localhost:1718/http://greenstone.org/meandre/flows/chromagram-v3/instance/greenstone-doc-id-service-to-signal/0?cmd=generate-audio-signal&docOID=abc
//    => Contacts the specified component in the running workflow
//    => Note: the port used (1718) is the value returned from using 'uri_flow.txt' above
//    =>       The URI given to the server on this port is the full URI 'name' shown in the Meandre Workbench for this components 



var MeandreController = function(webDomain, infrastructurePort, workbenchPort) 
{
    this.proxyURL = "/greenstone3/cgi-bin/meandre-proxy.pl";

    this.webDomain = webDomain || "http://localhost";

    this.infrastructurePort = (infrastructurePort || "1714");
    this.workbenchPort      = (workbenchPort || "1712");
    this.infrastructureBaseURL = this.webDomain + ":" + this.infrastructurePort;

    this.workbenchURL          = this.webDomain + ":" + this.workbenchPort + "/Workbench.html";
    
    this.initiateFlowServlet = "/services/execute/flow.txt";
    this.runningFlowServlet  = "/services/execute/uri_flow.txt";
    this.abortFlowServlet    = "/admin/abort.txt";

};


MeandreController.prototype.runFlow = function(flowURL) {

    console.log("**** using hardwired username of 'admin' for now");
    var username = "admin";

    var timestamp = new Date().getTime();
    var token = username + "_" + timestamp;

    var url = this.infrastructureBaseURL + this.initiateFlowServlet + "?statistics=true&uri=" + flowURL + "&token=" + token;
    var proxiedURL = this.proxyURL + "?" + encodeURIComponent(url);

    // Callback called when flow naturally finishes, or is stopped through an abort command
    var request = $.ajax({
    url: proxiedURL,
    cache: false
    });
    
    request.done(function(text) {
    console.info( "Meandre Flow completed for URL: " + url);
    });

    request.fail(function(jqXHR, textStatus) {
    alert( "Request for URL:\n\n    " + url + "\n\nfailed: " + textStatus + "\n--------\n" + jqXHR.statusText );
    });

    return token;
};



MeandreController.prototype.optionsToArgs = function(options) {

    var args = null;

    // nice if this could be done as a one-liner with 'join()'
    for (var k in options){
    if (args==null) {
        args = "";
    }
    else {
        args += "&";
    }

    args += k + "=" + options[k];
    }

    return args;
}

MeandreController.prototype.webComponentToURL = function(webDomain,port,webComp,options) {

    var args = this.optionsToArgs(options);

    var url = webDomain + ":" + port;

    if (webComp.indexOf("/") != 0) {
    url += "/";
    }
    url += webComp + "?" + args;

    return url;
}

function valuePairsTextToPropertyTable(text) {

    var lines = text.split("\n");

    for (var i=0; i<lines.length; i++) {
    var line = lines[i];
    
    var pair = line.match(/\s*(\w+)\s*=\s*(.*?)\s*$/);
    
    if ((pair!=null) && (pair.length==3)) {
        var metaname = pair[1];
        var metaval  = pair[2];
        
        // console.log("**** storing '"+metaname+"' = '" + metaval +"'");
        
        this[metaname] = metaval;
    }
    }

    //return props;
}

MeandreController.prototype.webComponentProperties = function(port,webComp,options) {

/*
    var args = this.optionsToArgs(options);

    var url = this.webDomain + ":" + port;

    if (webComp..indexOf("/") != 0) {
    url = + "/";
    }
    url += webComp + "?" + args;
*/

    var url = this.webComponentToURL(this.webDomain,port,webComp,options);

    // make *synchronous* call, and parse the returned text file as value-pairs

    var props = {};

    var proxiedURL = this.proxyURL + "?" + encodeURIComponent(url);

    var request = $.ajax({
    url: proxiedURL,
    context: props,
    async: false,
    cache: false
    });

    request.done(valuePairsTextToPropertyTable);

/*
function (text) {

    var lines = text.split("\n");
    for (var i=0; i<lines.length; i++) {
        var line = lines[i];

        var pair = line.match(/\s*(\w+)\s*=\s*(.*?)\s*$/);

        if ((pair!=null) && (pair.length==3)) {
        var metaname = pair[1];
        var metaval  = pair[2];
        
        // console.log("**** storing '"+metaname+"' = '" + metaval +"'");
        
        props[metaname] = metaval;
        }
    }
    });
*/

    request.fail(function(jqXHR, textStatus) {
    console.error( "Request for URL:\n\n    " + url + "\n\nfailed: " +  + textStatus + "\n--------\n" + jqXHR.statusText );
    });

    return props;
};


MeandreController.prototype.webComponent = function(port,webComp,options) {

    var payload = null;

    var url = this.webComponentToURL(this.webDomain,port,webComp,options);

    var proxiedURL = this.proxyURL + "?" + encodeURIComponent(url);

//    console.log("**** proxiedURL = " + proxiedURL);

    // Synchronous call to return returned output from URL
    var request = $.ajax({
    url: proxiedURL,
    async: false,
    cache: false
    });
    
    request.done(function(output) { 
    console.info( "Response of " + output.length + " bytes from URL: " + url + " received");
    payload = output;
    });

    request.fail(function(jqXHR, textStatus) {
    alert( "Request for URL:\n\n    " + url + "\n\nfailed: " +  textStatus + "\n--------\n" + jqXHR.statusText );
    });

    return payload;
};



MeandreController.prototype.binaryWebComponent = function(port,webComp,options, callback, context) {

    var payload = { data: null };
/*
    var args = optionsToArgs(options);

    var url = this.webDomain + ":" + port + "/" + webComp + "?" + args;
*/

    var url = this.webComponentToURL(this.webDomain,port,webComp,options);

    //console.log("binaryWebComponent: url = " + url);

    var timestamp = new Date().getTime();
    var proxiedURL = this.proxyURL + "?" + encodeURIComponent(url) + "&_=" + timestamp;

    // See if possible to do the same with jquery's ajax method ?? // ****

    var oReq = new XMLHttpRequest();
    oReq.open("GET",proxiedURL, true);
    oReq.responseType = "arraybuffer";

    oReq.onload = function (oEvent) { callback.call(context,oEvent,oReq) };

/*
    oReq.onload = function (oEvent) {

    var arrayBuffer = oReq.response; // Note: not oReq.responseText

    if (arrayBuffer.byteLength) {
        console.log("*** Recieved binary data: raw byte array buffer len = " + arrayBuffer.byteLength);

        var float32Array = new Float32Array(arrayBuffer); 

        payload.data = float32Array;
    }
    };
*/

    oReq.send(null);

    return payload;

};


MeandreController.prototype.runningFlowProperties = function(token) {

    var port    = this.infrastructurePort;
    var webComp = this.runningFlowServlet;
    var options = { statistics: true, token: token };

    var props = this.webComponentProperties(port,webComp,options);

    return props;
};


MeandreController.prototype.abortFlow = function(port) {

    var url = this.webDomain + ":" + port + this.abortFlowServlet;

    var proxiedURL = this.proxyURL + "?" + encodeURIComponent(url);

    // Asynchronous call to stop the given flow
    var request = $.ajax({
    url: proxiedURL
    });
    
    request.done(function(text) {
    console.info( "Request to abort Meandre Flow for URL: " + url + " issued");
    });

    request.fail(function(jqXHR, textStatus) {
    alert( "Request for URL:\n\n    " + url + "\n\nfailed: " +  textStatus + "\n--------\n" + jqXHR.statusText );
    });

};

MeandreController.prototype.loadWorkbench = function(frameId,workflowPos) {

    var url = this.workbenchURL + "?" + "displayMode=compact&workflowPos=" + workflowPos;
    //var proxiedURL = this.proxyURL + "?" + encodeURIComponent(url);

    $('#'+frameId).attr("src",url);

    //$('#'+frameId).attr("src",proxiedURL);

}