node-red-contrib-opcua/function connect_opcua_client code.txt

A Node-RED node to communicate via OPC UA based on node-opcua library.

//
// NEW CODE
//
async function connect_opcua_client() {
  // Refactored from old async Javascript to new Typescript with await
  
  // STEP 1
  // First connect to server´s endpoint
  verbose_log("Connecting to ", opcuaEndpoint.endpoint);
  try {
    set_node_status_to("connecting");
    if (!node.client) {
      verbose_log("No client to connect...");
    }
    await node.client.connect(opcuaEndpoint.endpoint);
  } catch (err) {
    set_node_status_to("invalid endpoint " + opcuaEndpoint.endpoint);
  }

  // STEP 2
  // This will succeed first time only if security policy and mode are None
  // Later user can use path and local file to access server certificate file
  const endpoints = await node.client.getEndpoints();
  let i = 0;
  endpoints.forEach(function (endpoint, i) {
    verbose_log("endpoint " + endpoint.endpointUrl + "");
    verbose_log("Application URI " + endpoint.server.applicationUri);
    verbose_log("Product URI " + endpoint.server.productUri);
    verbose_log("Application Name " + endpoint.server.applicationName.text);
    var applicationName = endpoint.server.applicationName.text;
    if (!applicationName) {
      applicationName = "OPCUA_Server";
    }
    verbose_log("Security Mode " + endpoint.securityMode.toString());
    verbose_log("securityPolicyUri " + endpoint.securityPolicyUri);
    verbose_log("Type " + endpoint.server.applicationType);
    verbose_log("certificate " + "..." + " /*endpoint.serverCertificate*/");
    endpoint.server.discoveryUrls = endpoint.server.discoveryUrls || [];
    verbose_log("discoveryUrls " + endpoint.server.discoveryUrls.join(" - "));
    var serverCertificate = endpoint.serverCertificate;
    // Use applicationName instead of fixed server_certificate
    var certificate_filename = path.join(__dirname, "../../PKI/" + applicationName + i + ".pem");
    if (serverCertificate) {
      fs.writeFile(certificate_filename, crypto_utils.toPem(serverCertificate, "CERTIFICATE"), function () {});
    }
  });

  endpoints.forEach(function (endpoint) {
    verbose_log("Identify Token for : Security Mode= " + endpoint.securityMode.toString(), " Policy=", endpoint.securityPolicyUri);
    endpoint.userIdentityTokens.forEach(function (token) {
      verbose_log("policyId " + token.policyId);
      verbose_log("tokenType " + token.tokenType.toString());
      verbose_log("issuedTokenType " + token.issuedTokenType);
      verbose_log("issuerEndpointUrl " + token.issuerEndpointUrl);
      verbose_log("securityPolicyUri " + token.securityPolicyUri);
    });
  });

  // STEP 3
  verbose_log("Create session ...");
  try {
    // TODO Add other security parameters to create session to server
    if (opcuaEndpoint.login === true) {
      verbose_log("Create session with userIdentity: " + JSON.stringify(userIdentity));
      //  {"clientName": "Node-red OPC UA Client node " + node.name},
      session = await node.client.createSession(userIdentity);
    } else {
      // ANONYMOUS no userIdentify to pass for creating session
      verbose_log("Create session as ANONYMOUS");
      let ANO: any;
      session = await node.client.createSession(ANO);
    }
    session.sessionName = "Node-red OPC UA Client node " + node.name;
    node.session = session;
    node.session.timeout = opcuaBasics.calc_milliseconds_by_time_and_unit(10, "s");
    verbose_log("session active");
    set_node_status_to("session active");
    for (var i in cmdQueue) {
      processInputMsg(cmdQueue[i]);
    }
    cmdQueue = [];
  } catch (err) {
    node_error(node.name + " OPC UA connection error: " + err.message);
    verbose_log(err);
    node.session = null;
    close_opcua_client(set_node_status_to("connection error"));
  }
}

//
// OLD CODE
//
    function connect_opcua_client() {
      //node.session = null;
      async.series([
          // First connect to server´s endpoint
          function (callback) {
            verbose_log("async series - connecting ", opcuaEndpoint.endpoint);
            try {
              set_node_status_to("connecting");
              if (!node.client) {
                verbose_log("No client to connect...");
              }
              node.client.connect(opcuaEndpoint.endpoint, callback);
            } catch (err) {
              if (err) {
                set_node_status_to("invalid endpoint " + opcuaEndpoint.endpoint);
              }
              // callback(err);
            }
          },
          function (callback) {
              // This will succeed first time only if security policy and mode are NONE
              // Later user can use path and local fileto access server certificate file
              node.client.getEndpoints(function (err, endpoints) {
                if (!err) {
                  endpoints.forEach(function (endpoint, i) {
                    verbose_log("endpoint " + endpoint.endpointUrl + "");
                    verbose_log("Application URI " + endpoint.server.applicationUri);
                    verbose_log("Product URI " + endpoint.server.productUri);
                    verbose_log("Application Name " + endpoint.server.applicationName.text);
                    var applicationName = endpoint.server.applicationName.text;
                    if (!applicationName) {
                      applicationName = "OPCUA_Server";
                    }
                    verbose_log("Security Mode " + endpoint.securityMode.toString());
                    verbose_log("securityPolicyUri " + endpoint.securityPolicyUri);
                    verbose_log("Type " + endpoint.server.applicationType.key);
                    verbose_log("certificate " + "..." + " /*endpoint.serverCertificate*/");
                    endpoint.server.discoveryUrls = endpoint.server.discoveryUrls || [];
                    verbose_log("discoveryUrls " + endpoint.server.discoveryUrls.join(" - "));
                    var serverCertificate = endpoint.serverCertificate;
                    // Use applicationName instead of fixed server_certificate
                    var certificate_filename = path.join(__dirname, "../../PKI/" + applicationName + i + ".pem");
                    if (serverCertificate) {
                       fs.writeFile(certificate_filename, crypto_utils.toPem(serverCertificate, "CERTIFICATE"),function(){});
                    }
                  });

                  endpoints.forEach(function (endpoint) {
                    verbose_log("Identify Token for : Security Mode= " + endpoint.securityMode.toString()," Policy=", endpoint.securityPolicyUri);
                    endpoint.userIdentityTokens.forEach(function (token) {
                      verbose_log("policyId " + token.policyId);
                      verbose_log("tokenType " + token.tokenType.toString());
                      verbose_log("issuedTokenType " + token.issuedTokenType);
                      verbose_log("issuerEndpointUrl " + token.issuerEndpointUrl);
                      verbose_log("securityPolicyUri " + token.securityPolicyUri);
                    });
                  });
                }
              callback(err);
            });
          },
          function (callback) {
            verbose_log("async series - create session ...");
            try {
              node.client.createSession(userIdentity, function (err, session) {
                if (!err) {
                  node.session = session;
                  node.session.timeout = opcuaBasics.calc_milliseconds_by_time_and_unit(10, "s");
                  //node.session.startKeepAliveManager(); // General for read/write/subscriptions/events
                  verbose_log("session active");
                  set_node_status_to("session active");
                  for (var i in cmdQueue) {
                    processInputMsg(cmdQueue[i]);
                  }
                  cmdQueue = [];
                  callback();
                } else {
                  set_node_status_to("session error");
                  callback(err);
                }
              });
            } catch (err) {
              callback(err);
            }
          }
        ],
        function (err) {
          if (err) {
            node_error(node.name + " OPC UA connection error: " + err.message);
            verbose_log(err);
            node.session = null;
            close_opcua_client(set_node_status_to("connection error"));
          }
        });
    }