ShowProcCommand.java

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// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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package org.apache.doris.nereids.trees.plans.commands;

import org.apache.doris.analysis.RedirectStatus;
import org.apache.doris.catalog.Column;
import org.apache.doris.catalog.Env;
import org.apache.doris.catalog.ScalarType;
import org.apache.doris.common.AnalysisException;
import org.apache.doris.common.ErrorCode;
import org.apache.doris.common.ErrorReport;
import org.apache.doris.common.proc.ProcNodeInterface;
import org.apache.doris.common.proc.ProcResult;
import org.apache.doris.common.proc.ProcService;
import org.apache.doris.mysql.privilege.PrivPredicate;
import org.apache.doris.nereids.trees.plans.PlanType;
import org.apache.doris.nereids.trees.plans.visitor.PlanVisitor;
import org.apache.doris.qe.ConnectContext;
import org.apache.doris.qe.ShowResultSet;
import org.apache.doris.qe.ShowResultSetMetaData;
import org.apache.doris.qe.StmtExecutor;

import java.util.List;

/**
 * show proc command
 */
public class ShowProcCommand extends ShowCommand {
    private final String path;

    /**
     * constructor
     */
    public ShowProcCommand(String path) {
        super(PlanType.SHOW_PROC_COMMAND);
        this.path = path;
    }

    /**
     * get meta for show proc
     */
    public ShowResultSetMetaData getMetaData(ProcNodeInterface procNode) {
        ShowResultSetMetaData.Builder builder = ShowResultSetMetaData.builder();
        ProcResult result = null;
        try {
            result = procNode.fetchResult();
        } catch (AnalysisException e) {
            return builder.build();
        }

        for (String col : result.getColumnNames()) {
            builder.addColumn(new Column(col, ScalarType.createVarchar(30)));
        }
        return builder.build();
    }

    @Override
    public ShowResultSetMetaData getMetaData() {
        return ShowResultSetMetaData.builder().build();
    }

    private ShowResultSet handleShowProc(ConnectContext ctx, StmtExecutor executor) throws Exception {
        if (!Env.getCurrentEnv().getAccessManager()
                .checkGlobalPriv(ctx, PrivPredicate.ADMIN_OR_NODE)) {
            ErrorReport.reportAnalysisException(ErrorCode.ERR_SPECIFIC_ACCESS_DENIED_ERROR, "ADMIN");
        }

        ProcNodeInterface procNode = ProcService.getInstance().open(path);
        List<List<String>> finalRows = procNode.fetchResult().getRows();
        ShowResultSet resultSet = new ShowResultSet(getMetaData(procNode), finalRows);
        return resultSet;
    }

    @Override
    public ShowResultSet doRun(ConnectContext ctx, StmtExecutor executor) throws Exception {
        return handleShowProc(ctx, executor);
    }

    @Override
    public <R, C> R accept(PlanVisitor<R, C> visitor, C context) {
        return visitor.visitShowProcCommand(this, context);
    }

    @Override
    public RedirectStatus toRedirectStatus() {
        if (ConnectContext.get().getSessionVariable().getForwardToMaster()) {
            return RedirectStatus.FORWARD_NO_SYNC;
        } else {
            return RedirectStatus.NO_FORWARD;
        }
    }
}