SOAP updateMeta operation for CustomSite

Question

I wanna change the homepage of a Force.com Site using the Metadata API. Nothing fancy, so:

• I've prepared a new updateMetadata request,
• set fullName to the API name of the site,
• put indexPage to the Visualforce Page,
• populate the other "required fields",

Then POST all that to the SOAP endpoint. But the response is a little bit confuzzling for me:

DUPLICATE_VALUE: A site with those parameters is already in use.

I guess it's true, the CustomSite exists, I want to update it. What am I missing here?

curl \
-X POST 'https://na1.salesforce.com/services/Soap/m/34.0' \
--header 'Content-Type: text/xml' \
--header 'SoapAction: ""' \
--data @request.xml

(request)
<?xml version="1.0" encoding="utf-8"?>
<env:Envelope xmlns:env="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <env:Header>
        <urn:SessionHeader xmlns:urn="http://soap.sforce.com/2006/04/metadata">
            <urn:sessionId>{session_id}</urn:sessionId>
        </urn:SessionHeader>
    </env:Header>
    <env:Body>
        <updateMetadata xmlns="http://soap.sforce.com/2006/04/metadata">
            <metadata xsi:type="CustomSite">
                <fullName>site_name</fullName>
                <indexPage>MySiteHomePage</indexPage>
                <clickjackProtectionLevel>SameOriginOnly</clickjackProtectionLevel>
                <masterLabel>my site label</masterLabel>
                <siteType>Visualforce</siteType>
                <requireHttps>false</requireHttps>
            </metadata>
        </updateMetadata>
    </env:Body>
</env:Envelope>

---

(response)
<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns="http://soap.sforce.com/2006/04/metadata">
    <soapenv:Body>
        <updateMetadataResponse>
            <result>
                <errors>
                    <message>A site with those parameters is already in use.</message>
                    <statusCode>DUPLICATE_VALUE</statusCode>
                </errors>
                <fullName>site_name</fullName>
                <success>false</success>
            </result>
        </updateMetadataResponse>
    </soapenv:Body>
</soapenv:Envelope>

Answer 1

Ack, added the urlPathPrefix tag to the request and found the problem:

The metadata definition must contain all fields applicable to the type, eg:

<metadata xsi:type="CustomSite">
    <fullName>site_name</fullName>
    <active>true</active>
    <allowHomePage>false</allowHomePage>
    <allowStandardAnswersPages>false</allowStandardAnswersPages>
    <allowStandardIdeasPages>false</allowStandardIdeasPages>
    <allowStandardLookups>false</allowStandardLookups>
    <allowStandardSearch>false</allowStandardSearch>
    <authorizationRequiredPage>Unauthorized</authorizationRequiredPage>
    <bandwidthExceededPage>BandwidthExceeded</bandwidthExceededPage>
    <clickjackProtectionLevel>SameOriginOnly</clickjackProtectionLevel>
    <customWebAddresses>
        <domainName>www.mydomain.com</domainName>
        <primary>true</primary>
    </customWebAddresses>
    <fileNotFoundPage>FileNotFound</fileNotFoundPage>
    <genericErrorPage>Exception</genericErrorPage>
    <inMaintenancePage>InMaintenance</inMaintenancePage>
    <indexPage>HomePage</indexPage>
    <masterLabel>site label</masterLabel>
    <requireHttps>false</requireHttps>
    <requireInsecurePortalAccess>false</requireInsecurePortalAccess>
    <siteAdmin>[email protected]</siteAdmin>
    <siteTemplate>MySiteTemplate</siteTemplate>
    <siteType>Visualforce</siteType>
    <subdomain>subdomain</subdomain>
    <urlPathPrefix>path</urlPathPrefix>
</metadata>

If any of the above fields are absent, they will be overwritten with nulls.