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Send multiple message over same TCP connection #32

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Send multiple message over same TCP connection #32

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9 changes: 9 additions & 0 deletions package.json
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -75,6 +75,11 @@
"key": "ctrl+alt+s",
"when": "editorLangId == hl7"
},
{
"command": "hl7tools.SendMultipleMessages",
"key": "ctrl+alt+g",
"when": "editorLangId == hl7"
},
{
"command": "hl7tools.StartListener",
"key": "ctrl+alt+l",
Expand Down Expand Up @@ -145,6 +150,10 @@
"command": "hl7tools.SendMessage",
"title": "HL7 Tools: Send Message"
},
{
"command": "hl7tools.SendMultipleMessages",
"title": "HL7 Tools: Send Multiple Messages"
},
{
"command": "hl7tools.StartListener",
"title": "HL7 Tools: Start Message Listener"
Expand Down
159 changes: 158 additions & 1 deletion src/SendHl7Message.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -10,10 +10,12 @@ import * as net from 'net';
import * as tls from 'tls';
import { SendHl7MessagePanel } from './SendHl7MessageWebPanel';
import { ExtensionPreferences } from './ExtensionPreferences';
import { Delimiter} from './Util';


// MLLP framing codes
const VT = String.fromCharCode(0x0b);
const FS = String.fromCharCode(0x1c);
const FS = String.fromCharCode(0x1c);
const CR = String.fromCharCode(0x0d);

//----------------------------------------------------
Expand Down Expand Up @@ -105,6 +107,8 @@ export function SendMessage(Host: string, Port: number, HL7Message: string, Time
});
}



// handler for socket timeouts
client.on('timeout', () => {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Connection to ' + Host + ':' + Port + ' has timed out waiting for a response. \r\n');
Expand Down Expand Up @@ -136,9 +140,162 @@ export function SendMessage(Host: string, Port: number, HL7Message: string, Time
Ack = Ack.replace(VT, "");
Ack = Ack.replace(FS + CR, "");
webViewPanel.updateStatus(Ack + '\r\n');
// client.destroy();
});

client.on('close', function (error: any) {
if (error) {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Connection to ' + Host + ':' + Port + ' has been closed due to an error.\r\n');
}
else {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Connection to ' + Host + ':' + Port + ' has been closed \r\n');
}
webViewPanel.updateStatus('\r\n');
});
}

//----------------------------------------------------
// Send a HL7 v2.x message to a remote host using MLLP framing.
// @param {string} Host - the DNS hostname or IP address of the remote host
// @param {int} Port - the TCP port of the remote host receiving the message.
// @param {string} HL7Message - a string representing a HL7 v2.x message
// @param {int} Timeout - the timeout value for the TCP socket in milliseconds. Defaults to 5000 if not supplied.
// @param {bool} UseTLS - if true connect using TLS
// @param {} encoding
// @param {object} webViewPanel - reference to webview panel object so that status update messages can be returned
export function SendMultipleMessages(Host: string, Port: number, HL7Message: string, Timeout: number, UseTls: boolean, IgnoreCertError: boolean, encoding: BufferEncoding, webViewPanel: SendHl7MessagePanel) {

// default to 5 second timeout for TCP socket if not supplied as a parameter
Timeout = Timeout || 5000;

// Establish a TCP socket connection to the remote host, write the HL7 message to the socket.
var preferences: ExtensionPreferences = new ExtensionPreferences();

var delimiters: Delimiter = new Delimiter();
delimiters.ParseDelimitersFromMessage(HL7Message);

var mshRegEx: RegExp = new RegExp("^MSH\\" + delimiters.Field, "gim");
var split: string[] = HL7Message.split(mshRegEx);

// loop through all matches, discarding anything before the first match (i.e batch header segments, or empty strings if MSH is the first segment)
for (var i = 1; i < split.length; i++) {
var newMessage = "MSH" + delimiters.Field + split[i];
split[i] = newMessage;

// replace any newlines added by the text area with CRs.
split[i] = split[i].replace(new RegExp('\n', 'g'), String.fromCharCode(0x0d));
}

var client: any;

//Keep track of message number
var j = 1;

// connect with TLS
if (UseTls) {

const tlsOptions = {
host: Host,
rejectUnauthorized: true // connections fail if this is set to false (??)
}

// load custom trusted CAs defined in user preferences
const trustedCAList: string[] = preferences.TrustedCertificateAuthorities;

// patch CreateSecureContext to add in custom CAs
// based on the Monkey Patch discussed in https://medium.com/trabe/monkey-patching-tls-in-node-js-to-support-self-signed-certificates-with-custom-root-cas-25c7396dfd2a
const origCreateSecureContext = tls.createSecureContext;
(tls.createSecureContext as any) = function(options: tls.SecureContextOptions) { // type assertion as any to work around read only property compiler warning
const context = origCreateSecureContext(options);
var pem: string = "";
for (let i:number = 0; i < trustedCAList.length; i++) {
if (fs.existsSync(trustedCAList[i])) {
pem += fs.readFileSync(trustedCAList[i], { encoding: "ascii" }).replace(/\r\n/g, "\n");
}
else {
console.log('User provided trusted CA not found: ' + trustedCAList[i]);
}
}
if (pem) {
const certs = pem.match(/-----BEGIN CERTIFICATE-----\n[\s\S]+?\n-----END CERTIFICATE-----/g);
if (!certs) {
console.log('Could not parse user defined root CA certificate(s)');
}
else {
certs.forEach(cert => {
context.context.addCACert(cert.trim());
});
}
}
return context;
};

client = tls.connect(Port, tlsOptions, function () {
// check for certificate validation errors
if (client.authorized) {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Connected to ' + Host + ':' + Port + ' using TLS \r\n');
client.write((VT + HL7Message + FS + CR), encoding);
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Message number ' + j + ' sent \r\n');
}
else {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] TLS connection to ' + Host + ':' + Port + ' failed \r\n');
}
});

}
// connect without TLS
else {
client = new net.Socket();
client.setTimeout(Timeout);
client.setEncoding(encoding);
client.connect(Port, Host, async function () {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Connected to ' + Host + ':' + Port + '\r\n');
client.write((VT + split[0] + FS + CR), encoding);
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Message number ' + j + ' sent \r\n');
});
}

// handler for socket timeouts
client.on('timeout', () => {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Connection to ' + Host + ':' + Port + ' has timed out waiting for a response. \r\n');
client.destroy();
});

client.on('error', function (e: any) {
if (e.code == 'ECONNREFUSED') {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Connection refused by ' + Host + ':' + Port + '\r\n');
}
else {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] An error occurred: ' + e.code + '\r\n');
if (e.code == 'UNABLE_TO_VERIFY_LEAF_SIGNATURE') {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Self Signed Certificates not supported.\r\n');
}
}
});

// error handler for sockets ended by remote endpoint.)
client.on('end', function (data: any) {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Socket closed by remote host. \r\n');
});

// receive ACK, log to console
client.on('data', function (data: any) {
// convert the ACK response to string, remove the MLLP header and footer characters.
var Ack: string = data.toString(encoding);
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] ACK Received: \r\n');
Ack = Ack.replace(VT, "");
Ack = Ack.replace(FS + CR, "");
webViewPanel.updateStatus(Ack + '\r\n');
j++
if (j>=split.length){
client.destroy();
}
else{
client.write((VT + split[j] + FS + CR), encoding);
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Message number ' + j + ' sent \r\n');
}
});

client.on('close', function (error: any) {
if (error) {
webViewPanel.updateStatus('[' + new Date().toLocaleTimeString() + '] Connection to ' + Host + ':' + Port + ' has been closed due to an error.\r\n');
Expand Down
57 changes: 56 additions & 1 deletion src/extension.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -12,7 +12,7 @@ import { ExtractAllFields, ExtractReturnCode } from './ExtractFields';
import { HighlightFields, HighlightFieldReturnCode } from './HighlightField';
import { DisplaySegmentAsTree } from './FieldTreeView';
import { MaskAllIdentifiers } from './MaskIdentifiers';
import { SendMessage } from './SendHl7Message'
import { SendMessage, SendMultipleMessages } from './SendHl7Message'
import { StartListener, StopListener } from './TCPListener';
import { CheckAllFields } from './CheckRequiredFields';
import { MissingRequiredFieldResult } from './CheckRequiredFieldsResult';
Expand Down Expand Up @@ -440,6 +440,61 @@ export function activate(context: vscode.ExtensionContext) {

context.subscriptions.push(SendMessageCommand);

//-------------------------------------------------------------------------------------------
// This function sends the message in the active document to a remote host via TCP. The HL7 message is framed using MLLP.
var SendMultipleMessagesCommand = vscode.commands.registerCommand('hl7tools.SendMultipleMessages', function () {

console.log("Sending HL7 message to remote host");

// get the user defaults for TCP Connection timeout & FavouriteRemoteHosts
const tcpConnectionTimeout = preferences.ConnectionTimeOut * 1000;

var activeEditor = vscode.window.activeTextEditor;
if (!activeEditor) {
console.log("No document open, nothing to send. Exiting 'hl7tools.SendMessage'");
return;
}

// get the HL7 message from the active document. Convert EOL to <CR> only.
var currentDoc = activeEditor.document;
var hl7Message = currentDoc.getText();
// get the EOL character from the current document
var endOfLineChar: string = Util.GetEOLCharacter(currentDoc);
hl7Message = hl7Message.replace(new RegExp(endOfLineChar, 'g'), String.fromCharCode(0x0d));

// display the webview panel
var thisExtension: vscode.Extension<any> | undefined = vscode.extensions.getExtension('RobHolme.hl7tools');
if (thisExtension === undefined) {
console.log("The extension 'RobHolme.hl7tools' could no be referenced.")
return;
}
var SendHl7MessageWebView: SendHl7MessagePanel = new SendHl7MessagePanel(thisExtension.extensionUri);
if (preferences.SocketEncodingPreference) {
SendHl7MessageWebView.encodingPreference = preferences.SocketEncodingPreference;
}
SendHl7MessageWebView.render(hl7Message);
// add any favourites from the user preferences to the webpanel's dropdown list
SendHl7MessageWebView.updateFavourites(preferences.FavouriteRemoteHosts);

// handle messages from the webview
SendHl7MessageWebView.panel.webview.onDidReceiveMessage(function (message) {
switch (message.command) {
case 'sendMessage':
SendMultipleMessages(message.host, message.port, message.hl7, tcpConnectionTimeout, message.tls, message.ignoreCertError, message.encoding, SendHl7MessageWebView);
return;
case 'exit':
SendHl7MessageWebView.panel.dispose();
return;
}
},
undefined,
context.subscriptions
);
});

context.subscriptions.push(SendMultipleMessagesCommand);


//-------------------------------------------------------------------------------------------
// This function receives messages from a remote host via TCP. Messages displayed in the editor as new documents.
var StartListenerCommand = vscode.commands.registerCommand('hl7tools.StartListener', function () {
Expand Down