You can pass the Channel attribute in SSO reponse to assign users to specific channels. A sample SSO response with Channel attribute is provided below. The channels listed in the SSO response will be automatically assigned to the corresponding users.
SSO Response Channel Attributes Example
<saml:AttributeStatement>
<saml:Attribute Name="Channel" NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:uri">
<saml:AttributeValue xsi:type="xs:string">{{ChannelUrl1}}</saml:AttributeValue>
<saml:AttributeValue xsi:type="xs:string">{{ChannelUrl2}}</saml:AttributeValue>
<saml:AttributeValue xsi:type="xs:string">{{ChannelUrl3}}</saml:AttributeValue>
</saml:Attribute>
</saml:AttributeStatement>