How to call M3 API from the Grid application proxy

Here is how to call M3 API using the MI-WS application proxy of the Infor Grid.

This is useful if we want to benefit from what is already setup in the Grid and not have to deal with creating our own connection to the M3 API server with Java library, hostname, port number, userid, password, connection pool, etc.

Note: For details on what Grid application proxies are, refer to the previous post.

MI-WS application proxy

The MI-WS application is part of the M3 Business Engine Foundation. We will need foundation-client.jar to compile our classes:

Step 1. Logon to the Grid

First, login to the Grid from your application and get a SessionId and optionally a GridPrincipal.

From a Grid application:

import com.lawson.grid.proxy.access.GridPrincipal;
import com.lawson.grid.proxy.access.SessionController;
import com.lawson.grid.proxy.access.SessionId;

// get session id
SessionId sid = ??? // PENDING
GridPrincipal principal = ??? // PENDING;

From a client application outside the Grid:

import com.lawson.grid.proxy.access.GridPrincipal;
import com.lawson.grid.proxy.access.SessionId;
import com.lawson.grid.proxy.access.SessionProvider;
import com.lawson.grid.proxy.access.SessionUtils;
import com.lawson.grid.proxy.ProxyException;

// logon and get session id
SessionUtils su = SessionUtils.getInstance(registry);
SessionProvider sp = su.getProvider(SessionProvider.TYPE_USER_PASSWORD);
SessionId sid;
try {
    sid = sp.logon(userid, password.toCharArray());
} catch (ProxyException e) {
    ...
}
GridPrincipal principal = su.getPrincipal(sid);

Step 2. Call the M3 API

Second, call the M3 API, for example CRS610MI.LstByNumber, and get the result:

import java.util.ArrayList;
import java.util.List;
import com.lawson.grid.proxy.ProxyClient;
import com.lawson.grid.proxy.ProxyException;
import com.lawson.miws.api.data.MIParameters;
import com.lawson.miws.api.data.MIParameters.ColumnList;
import com.lawson.miws.api.data.MIRecord;
import com.lawson.miws.api.data.MIResult;
import com.lawson.miws.api.MITransactionException;
import com.lawson.miws.proxy.MIAccessProxy;

// get the proxy
MIAccessProxy proxy = (MIAccessProxy)registry.getProxy(MIAccessProxy.class);

// login to M3
ProxyClient.setSessionId(proxy, sid);

// prepare the parameters
MIParameters paramMIParameters = new MIParameters();
paramMIParameters.setProgram("CRS610MI");
paramMIParameters.setTransaction("LstByNumber");
paramMIParameters.setMaxReturnedRecords(10);

// set the return columns
ColumnList returnColumns = new ColumnList();
List<String> returnColumnNames = new ArrayList<String>();
returnColumnNames.add("CONO");
returnColumnNames.add("CUNO");
returnColumnNames.add("CUNM");
returnColumns.setReturnColumnNames(returnColumnNames);
paramMIParameters.setReturnColumns(returnColumns);

// execute
MIResult result;
try {
	result = proxy.execute(paramMIParameters);
} catch (MITransactionException e) {
	...
} catch (ProxyException e) {
	...
}

// show the result
List<MIRecord> records = result.getResult();
for (MIRecord record: records) {
	record.toString();
}

Note: When I use ColumnList it throws java.io.NotSerializableException: com.lawson.miws.api.data.MIParameters$ColumnList. It appears to be a bug in that the ColumnList class is missing implements Serializable. I reported it in Infor Xtreme incident 8629267.

That’s it. Please let me know what you think in the comments below.