Build SOAP API Proxies | MuleSoft Documentation
# Build SOAP API Proxies
API Manager 2.x enables you to use SOAP API proxies for your SOAP-based web services. The SOAP proxy requires a WSDL definition that describes the backend service. The WSDL defines how the API proxy must perform validations on incoming requests and correctly routes outbound requests for the corresponding API endpoint.
## SOAP Proxy Schema Validation
Regardless of whether validation is enabled for an API, the SOAP request validator always verifies the following:
  * The incoming request has a valid SOAP action.
  * The payload is a valid SOAP envelope.


If validation is enabled for an API, the SOAP request validator also verifies that the content of the `body` tag matches the one defined in the WSDL. The SOAP action in the inbound request is matched against the same-named operation in the WSDL. The proxy then validates that the namespace URI of the element and the name associated with the operation match the same details in the incoming request.
If the validation fails, an error message informing the expected namespace URI and element name is generated. If the SOAP action in the inbound request is empty, the application then attempts to match the namespace URI and element name of the incoming request element to all the operations defined in the WSDL.
The first operation that matches the incoming request determines whether the validation is successful. If the match fails, an error message is generated with the suggested tag names for the element in the request.
## Retrieving the WSDL from the Proxy Application
The SOAP proxy allows the backend web service to post requests (POST) and to retrieve (GET) the service WSDL. The GET request is performed by an HTTP GET method with either `wsdl` or `WSDL` as the query parameter:
  * `http://my-proxy-url:myProxyPort?wsdl`
  * `http://my-proxy-url:myProxyPort?WSDL`


## Configuring a WSDL from Remote Location Using Basic Authentication Credentials
You can access a protected WSDL that is hosted on a remote location by configuring the `basic.auth.user` and `basic.auth.password` application properties in the `basicauth.properties` configuration file. The properties are then passed to the validator module:
```
<soap-request-validator:config name="validator-config" wsdlLocation="http://myremoteurl:9092/service?wsdl" serviceName="myServiceName"
                  servicePort="myServicePort" schemaValidationEnabled="true"
                  basicAuthUser="${basic.auth.user}" basicAuthPassword="${basic.auth.password}"/>
```

If you do not provide authentication values for the properties, the WSDL is retrieved unauthenticated.
## Retrieving a WSDL Using TLS
With SOAP proxy v2.1.0, you can retrieve a WSDL from a remote location using the TLS context configuration by default. The TLS context used for this operation is the same as the outbound configuration of the proxy.
## Configure Your SOAP Proxy
Configure your SOAP proxy by completing the following steps:
  1. Navigate to **Anypoint Platform** > **API Manager**.
  2. In **API Administration** , click **Add API** and select **Add new API**.
  3. Select **Mule Gateway** as your runtime.
  4. Select **Deploy a proxy application** for **Proxy type**.
  5. If you selected to deploy a proxy application, select the **Target type** from the following options:
     * **CloudHub 2.0** : Select this option if you want to use the Mule runtime hosted by MuleSoft in a container-based cloud infrastructure. The CloudHub 2.0 proxy includes a CPU with 0.1 vCores by default.
       1. Select a space.
To learn more about spaces, see Shared Spaces and Private Spaces.
       2. In **Runtime version** :
         1. Select the **Runtime Channel**.
         2. Select the **Version** for Mule runtime.
         3. Select the **Java version**.
       3. Enter a **Proxy app name**.
     * **CloudHub** : Select this option if you want to use the Mule runtime hosted on the cloud by MuleSoft. The CloudHub proxy includes a CPU with 0.1 vCores and a memory of 500 MB, by default.
       1. In **Runtime version** :
         1. Select the **Runtime Channel**.
         2. Select the **Version** for Mule runtime.
         3. Select the **Java version**.
       2. Enter a **Proxy app name**.
     * **Hybrid:** Select this option if you want to use a Mule runtime instance running on an on-premises server that is registered in Runtime Manager.
See Register a server in Runtime Manager for more information.
       1. Select a target from the list or click **Add server**.
       2. Enter a **Proxy app name**.
     * **Self-managed Server:** Select this option if you want to create a JAR file to deploy an API proxy to a Mule runtime instance running on an on-premises server that is not registered in Runtime Manager. For more information, see On-Premises Deployment Model.
Deploying an API proxy to a self-managed server in API Manager doesn’t deploy the proxy to your on-premises server. After you deploy the proxy in API Manager, deploy the proxy to your on-premises server: . Download your new API proxy JAR file. . Deploy the JAR file to your on-premises server.
  * **Runtime Fabric:** Select Runtime Fabric if you want to deploy API Proxies to a Mule runtime engine that is managed on Runtime Fabric. See Deploying API Proxies to Runtime Fabric for more information.
    1. Select a target from the list.
    2. In **Runtime version** :
      1. Select the **Runtime Channel**.
      2. Select the **Version** for Mule runtime.
      3. Select the **Java version**.
    3. Enter a **Proxy app name**.
      1. Select an API from the following options:
  * Click **Select API from Exchange** if you have an API shared with you through Exchange that you want to manage.
    1. Click the API from the list under **Select API**. You can search for a specific API if needed.
    2. Update the **Asset type** , **API version** , and **Asset version** if you are not using the latest version.
For more information about versions in Exchange, see Asset Versions.
    3. If you chose a **RAML/OAS** asset type, view the **Conformance Status** of the API to ensure the API is conformant. If the **Conformance Status** is nonconformant, after deployment, view the **Governance Report** to find and fix the conformance issues. For more information about the **Governance Report** , see Governing API Instances.
  * Click **Create new API** :
    1. Enter a **Name** for the new API asset.
    2. Select **SOAP API** as the **Asset type**.
    3. Select either **Upload a WSDL** or **Use an external link** as the method.
    4. Update the **Asset type** , **API version** , and **Asset version** if needed.
      1. Click **Next**.
      2. Configure the downstream configuration settings:
Expand for configuration settings.
Field Name | Description | Required | Notes  
---|---|---|---  
Specifies whether to use HTTP or HTTPS for the validations. | If you select HTTPS, specify a TLS context for inbound traffic.  
**Inbound TLS** | Specifies the TLS context to secure inbound traffic. | Only available on Mule 4+. If you can’t see a context, ensure that you have the correct permissions. To enable HTTPS in Mule 3 environment, see enable HTTPS in Mule 3x.  
Specifies the number to use if the displayed port is incorrect.  
Specifies the URL prefix for all API paths, relative to the host root. It must start and end with a leading slash `/`. If the final slash is not provided, the system adds it automatically.  
**Instance label** | Specifies a label for the API. | If you have multiple managed instances of the same API, add a label to differentiate each instance from the others.  
**Advanced Options**  
**Consumer endpoint** | Specifies a proxy application’s address for consumers to use for sending requests.  
**Client provider** | Specifies a client provider for the API. | Anypoint Platform acts as the client provider by default. To configure an external client provider, see Client Providers.  
**Request timeout** | Specifies the duration after which a request times out.  
**Proxy Version** | Specifies the version of the proxy to use for the endpoint.  
**Service Name** | Name of your WSDL service. | Only avaliable for WSDL APIs.  
**Service Port** | Port for your WSDL your service. | Only avaliable for WSDL APIs.  
**Service Namespace** | Namespace of your WSDL service. | Only avaliable for WSDL APIs.  
**Enable Console** | Specifies whether you can expose and test your API specification. | You can specify a different path in **Console Path** , for example, `/spec/*`. Only available if you have an attached API definition. Only available on Mule 3+.  
**Validations** | Specifies whether to validate inbound requests against a provided specification. | Only available if you have an attached API definition. Only available on Mule 3+.  
**Strict validations (optional)** | Specifies whether to validate inbound requests against query parameters. | Only available if you have an attached API definition. Only available on Mule 3+  
**User Domain** | Specifies whether to use an API gateway domain. | If you chose **Hybrid** as the proxy deployment target previously in the configuration, ensure that you select this option. You must install the API gateway domain in Mule 3.8 and later.  
      3. Click **Next**.
      4. Configure the upstream configuration settings:
Expand for configuration settings.
Field Name | Description | Required | Notes  
---|---|---|---  
**Upstream URL** | The URL to access for the proxy or the API. | For example, you can use the URL of your API asset in Exchange.  
**Outbound TLS** | Specifies the TLS context to secure outbound traffic. | Only available on Mule 4+. If you can’t see a context, ensure that you have the correct permissions.  
      5. Click **Next**.
      6. Review your selections and edit them if necessary.
      7. If you are ready to deploy, click **Save & Deploy**. Otherwise, you can select **Save** , to save the API instance and deploy it at a later time.


## Troubleshooting SOAP Proxies for Missing Imports on XSD Files
A SOAP proxy can fail during deployment due to an incorrect WSDL definition. For example, the following error indicates missing imports in one of the XSD files that are a part of the WSDL:
```
org.xml.sax.SAXParseException; systemId: http://localhost:8080/?wsdl304785538;
lineNumber: 2; columnNumber: 52; src-resolve.4.2: Error resolving component
'myNamespace:myElement’. It was detected that 'myNamespace:myElement' is in namespace
'http://my.namespace.url', but components from this namespace are not referenceable
from schema document 'http://localhost:8080/?wsdl304785538'. If this is the incorrect
namespace, perhaps the prefix of 'myNamespace:myElement' needs to be changed. If this
is the correct namespace, then an appropriate 'import' tag should be added to
'http://localhost:8080/?wsdl304785538'.
```

This issue occurs when the definition of an element that is used in the WSDL file is found in an external XSD with a namespace other than that of the current WSDL file.
You can resolve this issue by adding the appropriate imports in the WSDL file. For example, for the exception in the previous example, the WSDL file must contain the following import in the `types` element:
```
<types>
<schema xmlns="http://www.w3.org/2001/XMLSchema">
<import namespace="http://my.namespace.url" schemaLocation="myXSDFile.xsd"/>
</schema>
</types>
```

## See Also
  * Creating an API Instance by Importing from Exchange
  * Configure TLS Context for an API