io.druid.data.input.influx.InfluxParser.java Source code

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Here is the source code for io.druid.data.input.influx.InfluxParser.java

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/*
 * Licensed to Metamarkets Group Inc. (Metamarkets) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. Metamarkets 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
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package io.druid.data.input.influx;

import com.google.common.collect.ImmutableList;
import io.druid.java.util.common.parsers.ParseException;
import io.druid.java.util.common.parsers.Parser;
import org.antlr.v4.runtime.ANTLRInputStream;
import org.antlr.v4.runtime.CharStream;
import org.antlr.v4.runtime.CommonTokenStream;
import org.antlr.v4.runtime.TokenStream;

import javax.annotation.Nullable;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class InfluxParser implements Parser<String, Object> {
    public static final String TIMESTAMP_KEY = "__ts";
    private static final String MEASUREMENT_KEY = "measurement";
    private final Set<String> measurementWhitelist;

    public InfluxParser(Set<String> measurementWhitelist) {
        this.measurementWhitelist = measurementWhitelist;
    }

    @Override
    public void startFileFromBeginning() {
    }

    @Nullable
    @Override
    public Map<String, Object> parseToMap(String input) {
        CharStream charStream = new ANTLRInputStream(input);
        InfluxLineProtocolLexer lexer = new InfluxLineProtocolLexer(charStream);
        TokenStream tokenStream = new CommonTokenStream(lexer);
        InfluxLineProtocolParser parser = new InfluxLineProtocolParser(tokenStream);

        List<InfluxLineProtocolParser.LineContext> lines = parser.lines().line();
        if (parser.getNumberOfSyntaxErrors() != 0) {
            throw new ParseException("Unable to parse line.");
        }
        if (lines.size() != 1) {
            throw new ParseException("Multiple lines present; unable to parse more than one per record.");
        }

        Map<String, Object> out = new LinkedHashMap<>();

        InfluxLineProtocolParser.LineContext line = lines.get(0);
        String measurement = parseIdentifier(line.identifier());

        if (!checkWhitelist(measurement)) {
            throw new ParseException("Metric not whitelisted.");
        }

        out.put(MEASUREMENT_KEY, measurement);
        if (line.tag_set() != null) {
            line.tag_set().tag_pair().forEach(t -> parseTag(t, out));
        }

        line.field_set().field_pair().forEach(t -> parseField(t, out));

        if (line.timestamp() != null) {
            String timestamp = line.timestamp().getText();
            parseTimestamp(timestamp, out);
        }
        return out;
    }

    private void parseTag(InfluxLineProtocolParser.Tag_pairContext tag, Map<String, Object> out) {
        String key = parseIdentifier(tag.identifier(0));
        String value = parseIdentifier(tag.identifier(1));
        out.put(key, value);
    }

    private void parseField(InfluxLineProtocolParser.Field_pairContext field, Map<String, Object> out) {
        String key = parseIdentifier(field.identifier());
        InfluxLineProtocolParser.Field_valueContext valueContext = field.field_value();
        Object value;
        if (valueContext.NUMBER() != null) {
            value = parseNumber(valueContext.NUMBER().getText());
        } else if (valueContext.BOOLEAN() != null) {
            value = parseBool(valueContext.BOOLEAN().getText());
        } else {
            value = parseQuotedString(valueContext.QUOTED_STRING().getText());
        }
        out.put(key, value);
    }

    private Object parseQuotedString(String text) {
        return text.substring(1, text.length() - 1).replaceAll("\\\\\"", "\"");
    }

    private Object parseNumber(String raw) {
        if (raw.endsWith("i")) {
            return new Long(raw.substring(0, raw.length() - 1));
        }

        return new Double(raw);
    }

    private Object parseBool(String raw) {
        char first = raw.charAt(0);
        if (first == 't' || first == 'T') {
            return "true";
        } else {
            return "false";
        }
    }

    private String parseIdentifier(InfluxLineProtocolParser.IdentifierContext ctx) {
        if (ctx.BOOLEAN() != null || ctx.NUMBER() != null) {
            return ctx.getText();
        }

        return ctx.IDENTIFIER_STRING().getText().replaceAll("\\\\([,= ])", "$1");
    }

    private boolean checkWhitelist(String m) {
        return (measurementWhitelist == null) || measurementWhitelist.contains(m);
    }

    private void parseTimestamp(String timestamp, Map<String, Object> dest) {
        // Influx timestamps come in nanoseconds; treat anything less than 1 ms as 0
        if (timestamp.length() < 7) {
            dest.put(TIMESTAMP_KEY, 0L);
        } else {
            timestamp = timestamp.substring(0, timestamp.length() - 6);
            long timestampMillis = new Long(timestamp);
            dest.put(TIMESTAMP_KEY, timestampMillis);
        }
    }

    @Override
    public List<String> getFieldNames() {
        return ImmutableList.of();
    }

    @Override
    public void setFieldNames(Iterable<String> fieldNames) {
    }
}