Spring OAuth2 - Can't get Client Credentials

I'm not 100% sure I'm performing the correct request but I can't seem to get a token for a client. I've based my solution off of this tutorial 5 minutes with spring oauth 2.0.

I'm performing this request from postman:

/oauth/token?grant_type=client_credentials&client_id=mysupplycompany&client_secret=mycompanyk

That request responds with an exception:

org.springframework.security.authentication.InsufficientAuthenticationException: There is no client authentication. Try adding an appropriate authentication filter. org.springframework.security.oauth2.provider.endpoint.TokenEndpoint.postAccessToken(TokenEndpoint.java:91)

Below are some files/classes you may need to help me figure out any issues.

security-spring.xml

<?xml version="1.0" encoding="UTF-8" ?>
<beans xmlns="http://ift.tt/GArMu6"
    xmlns:xsi="http://ift.tt/ra1lAU" xmlns:oauth="http://ift.tt/1bBHntb"
    xmlns:sec="http://ift.tt/1c8inpe" xmlns:mvc="http://ift.tt/1bHqwjR"
    xsi:schemaLocation="http://ift.tt/1bBHntb http://ift.tt/1aErTAF
        http://ift.tt/1c8inpe http://ift.tt/1epvZ6L
        http://ift.tt/GArMu6 http://ift.tt/1CZCNBy 
        http://ift.tt/1bHqwjR http://ift.tt/YzZ6hD">


    <sec:http pattern="/oauth/token" create-session="stateless"
        authentication-manager-ref="authenticationManager">
        <sec:intercept-url pattern="/oauth/token" access="IS_AUTHENTICATED_FULLY" />
        <sec:anonymous enabled="false" />
        <sec:http-basic entry-point-ref="clientAuthenticationEntryPoint" />
        <sec:custom-filter ref="clientCredentialsTokenEndpointFilter"
            before="BASIC_AUTH_FILTER" />
        <sec:access-denied-handler ref="oauthAccessDeniedHandler" />
    </sec:http>

    <sec:http pattern="/api/**" create-session="never"
        entry-point-ref="oauthAuthenticationEntryPoint">
        <sec:anonymous enabled="false" />
        <sec:intercept-url pattern="/api/**" method="GET"
            access="IS_AUTHENTICATED_FULLY" />
        <sec:custom-filter ref="resourceServerFilter"
            before="PRE_AUTH_FILTER" />
        <sec:access-denied-handler ref="oauthAccessDeniedHandler" />
    </sec:http>

    <bean id="oauthAuthenticationEntryPoint"
        class="org.springframework.security.oauth2.provider.error.OAuth2AuthenticationEntryPoint">
    </bean>

    <bean id="clientAuthenticationEntryPoint"
        class="org.springframework.security.oauth2.provider.error.OAuth2AuthenticationEntryPoint">
        <property name="realmName" value="springsec/client" />
        <property name="typeName" value="Basic" />
    </bean>

    <bean id="oauthAccessDeniedHandler"
        class="org.springframework.security.oauth2.provider.error.OAuth2AccessDeniedHandler">
    </bean>

    <bean id="clientCredentialsTokenEndpointFilter"
        class="org.springframework.security.oauth2.provider.client.ClientCredentialsTokenEndpointFilter">
        <property name="authenticationManager" ref="authenticationManager" />
    </bean>

    <sec:authentication-manager alias="authenticationManager">
        <sec:authentication-provider
            user-service-ref="clientDetailsUserService" />
    </sec:authentication-manager>

    <bean id="clientDetailsUserService"
        class="org.springframework.security.oauth2.provider.client.ClientDetailsUserDetailsService">
        <constructor-arg ref="clientDetails" />
    </bean>

    <bean id="clientDetails" class="com.squirrels.auth.OAuthClientDetailsImpl">
        <property name="id" value="mysupplycompany" />
        <property name="secretKey" value="mycompanykey" />
    </bean>

    <sec:authentication-manager id="userAuthenticationManager">
        <sec:authentication-provider ref="customUserAuthenticationProvider" />
    </sec:authentication-manager>

    <bean id="customUserAuthenticationProvider" class="com.squirrels.auth.OAuthAuthenticationProvider">
    </bean>

    <oauth:authorization-server
        client-details-service-ref="clientDetails" token-services-ref="tokenServices">
        <oauth:authorization-code />
        <oauth:implicit />
        <oauth:refresh-token />
        <oauth:client-credentials />
        <oauth:password authentication-manager-ref="userAuthenticationManager" />
    </oauth:authorization-server>

    <oauth:resource-server id="resourceServerFilter"
        resource-id="springsec" token-services-ref="tokenServices" />

    <bean id="tokenStore"
        class="org.springframework.security.oauth2.provider.token.store.InMemoryTokenStore" />

    <bean id="tokenServices"
        class="org.springframework.security.oauth2.provider.token.DefaultTokenServices">
        <property name="tokenStore" ref="tokenStore" />
        <property name="supportRefreshToken" value="true" />
        <property name="accessTokenValiditySeconds" value="120"></property>
        <property name="clientDetailsService" ref="clientDetails" />
    </bean>

    <mvc:annotation-driven />
</beans>

OAuthAuthenticationProvider

package com.squirrels.auth;

import java.util.ArrayList;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.AuthenticationProvider;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.AuthenticationException;
import org.springframework.security.core.GrantedAuthority;

public class OAuthAuthenticationProvider implements AuthenticationProvider {

    @Autowired
    private OAuthProxy proxy;

    @Override
    public Authentication authenticate(Authentication authentication) throws AuthenticationException {
        boolean result = proxy.isValidUser("1", authentication.getPrincipal().toString(), authentication.getCredentials().toString());

        if (result) {
            List<GrantedAuthority> grantedAuthorities =

            new ArrayList<GrantedAuthority>();
            OAuthAuthenticationToken auth = new OAuthAuthenticationToken(authentication.getPrincipal(), authentication.getCredentials(), grantedAuthorities);

            return auth;
        } else {
            throw new BadCredentialsException("Bad User Credentials.");
        }
    }

    @Override
    public boolean supports(Class<?> arg0) {
        return true;
    }

}

OAuthenticationToken

package com.squirrels.auth;

import java.util.Collection;

import org.springframework.security.authentication.AbstractAuthenticationToken;
import org.springframework.security.core.GrantedAuthority;

public class OAuthAuthenticationToken extends AbstractAuthenticationToken {

    private static final long serialVersionUID = -1092219614309982278L;
    private final Object principal;
    private Object credentials;

    public OAuthAuthenticationToken(Object principal, Object credentials,
            Collection<? extends GrantedAuthority> authorities) {
        super(authorities);
        this.principal = principal;
        this.credentials = credentials;
        super.setAuthenticated(true);
    }

    @Override
    public Object getCredentials() {
        return credentials;
    }

    @Override
    public Object getPrincipal() {
        return principal;
    }

}

OAuthClientDetailsImpl

package com.squirrels.auth;

import java.util.ArrayList;
import java.util.List;

import org.springframework.security.oauth2.provider.ClientDetails;
import org.springframework.security.oauth2.provider.ClientDetailsService;
import org.springframework.security.oauth2.provider.ClientRegistrationException;
import org.springframework.security.oauth2.provider.NoSuchClientException;
import org.springframework.security.oauth2.provider.client.BaseClientDetails;

public class OAuthClientDetailsImpl implements ClientDetailsService {

    private String id;
    private String secretKey;

    @Override
    public ClientDetails loadClientByClientId(String clientId) throws ClientRegistrationException {
        if (clientId.equals(id))
        {
            List<String> authorizedGrantTypes = new ArrayList<String>();
            authorizedGrantTypes.add("password");
            authorizedGrantTypes.add("refresh_token");
            authorizedGrantTypes.add("client_credentials");

            BaseClientDetails clientDetails = new BaseClientDetails();
            clientDetails.setClientId(id);
            clientDetails.setClientSecret(secretKey);
            clientDetails.setAuthorizedGrantTypes(authorizedGrantTypes);

            return clientDetails;
        }
        else {
            throw new NoSuchClientException("No client recognized with id: " + clientId);
        }
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getSecretKey() {
        return secretKey;
    }

    public void setSecretKey(String secretKey) {
        this.secretKey = secretKey;
    }

}

OAuthProxy

package com.squirrels.auth;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import com.squirrels.dto.UserDTO;
import com.squirrels.persistence.dao.UserDao;
import com.squirrels.persistence.model.UserModel;
import com.squirrels.services.UserUtil;


@Service
public class OAuthProxy {

    protected static final Logger logger = LogManager.getLogger(OAuthProxy.class);

    @Autowired
    private UserDao userDaoImpl;

    @Autowired
    private UserUtil userUtil;  

    @Transactional
    public boolean isValidUser(String organizationId, String username, String password) {

        try{
            UserModel user = userDaoImpl.findByOrganizationAndUserName(organizationId, username);
            UserDTO userDto = userUtil.getDTO(user);

            //TODO validate password (or other means of auth)

            return true;            
        }catch(Exception e){
            logger.error("No user: " + username + " found in organization: " + organizationId, e);
        }

        return false;
    }

}