soap

What is soap?

The 'soap' npm package is a SOAP client and server library for Node.js. It allows you to create SOAP clients to consume web services and also create SOAP servers to expose your own web services.

What are soap's main functionalities?

Create a SOAP Client

This feature allows you to create a SOAP client that can consume a SOAP web service. You provide the WSDL URL, and the client can then call the web service methods.

const soap = require('soap');
const url = 'http://example.com/wsdl?wsdl';
soap.createClient(url, function(err, client) {
  if (err) throw err;
  client.MyFunction({name: 'value'}, function(err, result) {
    if (err) throw err;
    console.log(result);
  });
});

Create a SOAP Server

This feature allows you to create a SOAP server that exposes your own web service. You define the service and its methods, and provide the WSDL file.

const soap = require('soap');
const express = require('express');
const app = express();
const myService = {
  MyService: {
    MyPort: {
      MyFunction: function(args) {
        return { name: args.name };
      }
    }
  }
};
const xml = require('fs').readFileSync('myservice.wsdl', 'utf8');
soap.listen(app, '/wsdl', myService, xml);
app.listen(8000);

Handle SOAP Headers

This feature allows you to add custom SOAP headers to your SOAP client requests. This can be useful for authentication or other custom header requirements.

const soap = require('soap');
const url = 'http://example.com/wsdl?wsdl';
soap.createClient(url, function(err, client) {
  if (err) throw err;
  const soapHeader = { 'MyHeader': 'value' };
  client.addSoapHeader(soapHeader);
  client.MyFunction({name: 'value'}, function(err, result) {
    if (err) throw err;
    console.log(result);
  });
});

Other packages similar to soap

strong-soap

The 'strong-soap' package is another SOAP client and server library for Node.js. It is similar to 'soap' but offers additional features like better WSDL handling and support for more complex SOAP scenarios. It is maintained by the StrongLoop team.

easy-soap-request

The 'easy-soap-request' package is a lightweight SOAP client for Node.js. It focuses on simplicity and ease of use, making it a good choice for simple SOAP requests. However, it does not offer server-side capabilities like 'soap'.

node-soap-client

The 'node-soap-client' package is a minimalistic SOAP client for Node.js. It is designed to be easy to use and integrates well with modern JavaScript features like Promises and async/await. It is a good alternative if you only need client-side functionality.

README

Soap

A SOAP client and server for node.js.

This module lets you connect to web services using SOAP. It also provides a server that allows you to run your own SOAP services.

Features:

• Very simple API
• Handles both RPC and Document schema types
• Supports multiRef SOAP messages (thanks to @kaven276)
• Support for both synchronous and asynchronous method handlers
• WS-Security (currently only UsernameToken and PasswordText encoding is supported)

Install

Install with npm:

  npm install soap

Module

soap.createClient(url[, options], callback) - create a new SOAP client from a WSDL url. Also supports a local filesystem path.

  var soap = require('soap');
  var url = 'http://example.com/wsdl?wsdl';
  var args = {name: 'value'};
  soap.createClient(url, function(err, client) {
      client.MyFunction(args, function(err, result) {
          console.log(result);
      });
  });

Options

The options argument allows you to customize the client with the following properties:

• endpoint: to override the SOAP service's host specified in the .wsdl file.
• request: to override the request module.
• httpClient: to provide your own http client that implements request(rurl, data, callback, exheaders, exoptions).

soap.listen(server, path, services, wsdl) - create a new SOAP server that listens on path and provides services.

wsdl is an xml string that defines the service.

  var myService = {
      MyService: {
          MyPort: {
              MyFunction: function(args) {
                  return {
                      name: args.name
                  };
              },

              // This is how to define an asynchronous function.
              MyAsyncFunction: function(args, callback) {
                  // do some work
                  callback({
                      name: args.name
                  })
              },

              // This is how to receive incoming headers
              HeadersAwareFunction: function(args, cb, headers) {
                  return {
                      name: headers.Token
                  };
              }
          }
      }
  }

  var xml = require('fs').readFileSync('myservice.wsdl', 'utf8'),
      server = http.createServer(function(request,response) {
          response.end("404: Not Found: "+request.url)
      });

  server.listen(8000);
  soap.listen(server, '/wsdl', myService, xml);

Server Logging

If the log method is defined it will be called with 'received' and 'replied' along with data.

  server = soap.listen(...)
  server.log = function(type, data) {
    // type is 'received' or 'replied'
  };

Server Events

Server instances emit the following events:

• request - Emitted for every received messages. The signature of the callback is function(request, methodName).
• headers - Emitted when the SOAP Headers are not empty. The signature of the callback is function(headers, methodName).

The sequence order of the calls is request, headers and then the dedicated service method.

SOAP Fault

A service method can reply with a SOAP Fault to a client by throwing an object with a Fault property.

  throw {
    Fault: {
      Code: {
        Value: "soap:Sender",
        Subcode: { value: "rpc:BadArguments" }
      },
      Reason: { Text: "Processing Error" }
    }
  };

To change the HTTP statusCode of the response include it on the fault. The statusCode property will not be put on the xml message.

  throw {
    Fault: {
      Code: {
        Value: "soap:Sender",
        Subcode: { value: "rpc:BadArguments" }
      },
      Reason: { Text: "Processing Error" },
      statusCode: 500
    }
  };

SOAP Headers

A service method can look at the SOAP headers by providing a 3rd arguments.

  {
      HeadersAwareFunction: function(args, cb, headers) {
          return {
              name: headers.Token
          };
      }
  }

It is also possible to subscribe to the 'headers' event. The event is triggered before the service method is called, and only when the SOAP Headers are not empty.

  server = soap.listen(...)
  server.on('headers', function(headers, methodName) {
    // It is possible to change the value of the headers
    // before they are handed to the service method.
    // It is also possible to throw a SOAP Fault
  });

First parameter is the Headers object; second parameter is the name of the SOAP method that will called (in case you need to handle the headers differently based on the method).

Server security example using PasswordDigest

If server.authenticate is not defined then no authentication will take place.

  server = soap.listen(...)
  server.authenticate = function(security) {
    var created, nonce, password, user, token;
    token = security.UsernameToken, user = token.Username,
            password = token.Password, nonce = token.Nonce, created = token.Created;
    return user === 'user' && password === soap.passwordDigest(nonce, created, 'password');
  };

Server connection authorization

The server.authorizeConnection method is called prior to the soap service method. If the method is defined and returns false then the incoming connection is terminated.

  server = soap.listen(...)
  server.authorizeConnection = function(req) {
    return true; // or false
  };

Client

An instance of Client is passed to the soap.createClient callback. It is used to execute methods on the soap service.

Client.describe() - description of services, ports and methods as a JavaScript object

  client.describe() // returns
    {
      MyService: {
        MyPort: {
          MyFunction: {
            input: {
              name: 'string'
            }
          }
        }
      }
    }

Client.setSecurity(security) - use the specified security protocol

node-soap has several default security protocols. You can easily add your own as well. The interface is quite simple. Each protocol defines 2 methods:

• addOptions - a method that accepts an options arg that is eventually passed directly to request
• toXML - a method that returns a string of XML.

By default there are 3 protocols:

####BasicAuthSecurity

  client.setSecurity(new soap.BasicAuthSecurity('username', 'password'));

####ClientSSLSecurity Note: If you run into issues using this protocol, consider passing these options as default request options to the constructor:

• rejectUnauthorized: false
• strictSSL: false
• secureOptions: constants.SSL_OP_NO_TLSv1_2 (this is likely needed for node >= 10.0)

  client.setSecurity(new soap.ClientSSLSecurity(
    '/path/to/key'
    , '/path/to/cert'
    , {/*default request options*/}
  ));

####WSSecurity

  client.setSecurity(new soap.WSSecurity('username', 'password'))

####BearerSecurity

  client.setSecurity(new soap.BearerSecurity('token'));

Client.method(args, callback) - call method on the SOAP service.

  client.MyFunction({name: 'value'}, function(err, result, raw, soapHeader) {
      // result is a javascript object
      // raw is the raw response
      // soapHeader is the response soap header as a javascript object
  })

Client.service.port.method(args, callback[, options]) - call a method using a specific service and port

  client.MyService.MyPort.MyFunction({name: 'value'}, function(err, result) {
      // result is a javascript object
  })

###Overriding the namespace prefix node-soap is still working out some kinks regarding namespaces. If you find that an element is given the wrong namespace prefix in the request body, you can add the prefix to it's name in the containing object. I.E.:

  client.MyService.MyPort.MyFunction({'ns1:name': 'value'}, function(err, result) {
      // request body sent with `<ns1:name`, regardless of what the namespace should have been.
  }, {timeout: 5000})

Options (optional)

• Accepts any option that the request module accepts, see here.
• For example, you could set a timeout of 5 seconds on the request like this:

  client.MyService.MyPort.MyFunction({name: 'value'}, function(err, result) {
      // result is a javascript object
  }, {timeout: 5000})

Client.addSoapHeader(soapHeader[, name, namespace, xmlns]) - add soapHeader to soap:Header node

Options

• soapHeader Object({rootName: {name: "value"}}) or strict xml-string

Optional parameters when first arg is object :

• name Unknown parameter (it could just a empty string)
• namespace prefix of xml namespace
• xmlns URI

Client.lastRequest - the property that contains last full soap request for client logging

Client Events

Client instances emit the following events:

• request - Emitted before a request is sent. The event handler receives the entire Soap request (Envelope) including headers.
• message - Emitted before a request is sent. The event handler receives the Soap body contents. Useful if you don't want to log /store Soap headers.
• soapError - Emitted when an erroneous response is received. Useful if you want to globally log errors.
• response - Emitted after a response is received. The event handler receives the entire response body. This is emitted for all responses (both success and errors).

WSSecurity

WSSecurity implements WS-Security. UsernameToken and PasswordText/PasswordDigest is supported. An instance of WSSecurity is passed to Client.setSecurity.

  new WSSecurity(username, password, options)
    //the 'options' object is optional and contains properties:
    //passwordType: 'PasswordDigest' or 'PasswordText' default is PasswordText
    //hasTimeStamp: true or false default is true

Handling XML Attributes, Value and XML (wsdlOptions).

Sometimes it is necessary to override the default behaviour of node-soap in order to deal with the special requirements of your code base or a third library you use. Therefore you can use the wsdlOptions Object, which is passed in the #createClient() method and could have any (or all) of the following contents:

var wsdlOptions = {
  attributesKey: 'theAttrs',
  valueKey: 'theVal',
  xmlKey: 'theXml'
}

If nothing (or an empty Object {}) is passed to the #createClient() method, the node-soap defaults (attributesKey: 'attributes', valueKey: '$value' and xmlKey: '$xml') are used.

###Overriding the value key By default, node-soap uses $value as key for any parsed XML value which may interfere with your other code as it could be some reserved word, or the $ in general cannot be used for a key to start with.

You can define your own valueKey by passing it in the wsdl_options to the createClient call like so:

var wsdlOptions = {
  valueKey: 'theVal'
};

soap.createClient(__dirname + '/wsdl/default_namespace.wsdl', wsdlOptions, function (err, client) {
  // your code
});

###Overriding the xml key As valueKey, node-soap uses $xml as key. The xml key is used to pass XML Object without adding namespace or parsing the string.

Example :

dom = {
     $xml: '<parentnode type="type"><childnode></childnode></parentnode>'
};

<tns:dom>
    <parentnode type="type">
          <childnode></childnode>
    </parentnode>
</tns:dom>

You can define your own xmlKey by passing it in the wsdl_options to the createClient call like so:

var wsdlOptions = {
  xmlKey: 'theXml'
};

soap.createClient(__dirname + '/wsdl/default_namespace.wsdl', wsdlOptions, function (err, client) {
  // your code
});

###Overriding the attributes key You can achieve attributes like:

<parentnode>
  <childnode name="childsname">
  </childnode>
</parentnode>

By attaching an attributes object to a node.

{
  parentnode: {
    childnode: {
      attributes: {
        name: 'childsname'
      }
    }
  }
}

However, "attributes" may be a reserved key for some systems that actually want a node

<attributes>
</attributes>

In this case you can configure the attributes key in the wsdlOptions like so.

var wsdlOptions = {
  attributesKey: '$attributes'
};

soap.createClient(__dirname + '/wsdl/default_namespace.wsdl', wsdlOptions, function (err, client) {
  client.*method*({
    parentnode: {
      childnode: {
        $attributes: {
          name: 'childsname'
        }
      }
    }
  });
});

Handling "ignored" namespaces

If an Element in a schema definition depends on an Element which is present in the same namespace, normally the tns: namespace prefix is used to identify this Element. This is not much of a problem as long as you have just one schema defined (inline or in a separate file). If there are more schema files, the tns: in the generated soap file resolved mostly to the parent wsdl file, which was obviously wrong.

node-soap now handles namespace prefixes which shouldn't be resolved (because it's not necessary) as so called ignoredNamespaces which default to an Array of 3 Strings (['tns', 'targetNamespace', 'typedNamespace']).

If this is not sufficient for your purpose you can easily add more namespace prefixes to this Array, or override it in its entirety by passing an ignoredNamespaces object within the options you pass in soap.createClient() method.

A simple ignoredNamespaces object, which only adds certain namespaces could look like this:

var options = {
  ignoredNamespaces: {
    namespaces: ['namespaceToIgnore', 'someOtherNamespace']
  }
}

This would extend the ignoredNamespaces of the WSDL processor to ['tns', 'targetNamespace', 'typedNamespace', 'namespaceToIgnore', 'someOtherNamespace'].

If you want to override the default ignored namespaces you would simply pass the following ignoredNamespaces object within the options:

var options = {
    ignoredNamespaces: {
      namespaces: ['namespaceToIgnore', 'someOtherNamespace'],
      override: true
    }
  }

This would override the default ignoredNamespaces of the WSDL processor to ['namespaceToIgnore', 'someOtherNamespace']. (This shouldn't be necessary, anyways).

If you want to override the default ignored namespaces you would simply pass the following ignoredNamespaces object within the options:

var options = {
    ignoredNamespaces: {
      namespaces: ['namespaceToIgnore', 'someOtherNamespace'],
      override: true
    }
  }

This would override the default ignoredNamespaces of the WSDL processor to ['namespaceToIgnore', 'someOtherNamespace']. (This shouldn't be necessary, anyways).

Handling "ignoreBaseNameSpaces" attribute

If an Element in a schema definition depends has a basenamespace defined but the request does not need that value, for example you have a "sentJob" with basenamespace "v20" but the request need only: set in the tree structure, you need to set the ignoreBaseNameSpaces to true. This is set because in a lot of workaround the wsdl structure is not correctly set or the webservice bring errors.

By default the attribute is set to true. An example to use:

A simple ignoredNamespaces object, which only adds certain namespaces could look like this:

var options = {
ignoredNamespaces: true
}

Contributors

• Author: Vinay Pulim
• Maintainers:
  • Joe Spencer
  • Heinz Romirer
• All Contributors