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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/* @test
 * @bug 8061729
 * @library /test/lib
 * @summary Sanity check that HttpHeaderParser works same as MessageHeader
 * @modules java.base/sun.net.www java.base/sun.net.www.protocol.http:open
 * @run testng/othervm HttpHeaderParserTest
 */

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;

import static java.lang.String.format;
import static java.nio.charset.StandardCharsets.ISO_8859_1;
import static java.nio.charset.StandardCharsets.US_ASCII;
import jdk.test.lib.net.HttpHeaderParser;
import static org.testng.Assert.assertEquals;
import static org.testng.Assert.assertTrue;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;
import sun.net.www.MessageHeader;

public class HttpHeaderParserTest {
    @DataProvider(name = "responses")
    public Object[][] responses() {
        List<String> responses = new ArrayList<>();

        String[] basic =
                { "HTTP/1.1 200 OK\r\n\r\n",

                        "HTTP/1.1 200 OK\r\n" +
                                "Date: Mon, 15 Jan 2001 12:18:21 GMT\r\n" +
                                "Server: Apache/1.3.14 (Unix)\r\n" +
                                "Connection: close\r\n" +
                                "Content-Type: text/html; charset=iso-8859-1\r\n" +
                                "Content-Length: 10\r\n\r\n" +
                                "123456789",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length: 9\r\n" +
                                "Content-Type: text/html; charset=UTF-8\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "X-Header: U\u00ffU\r\n" + // value with U+00FF - Extended Latin-1
                                "Content-Length: 9\r\n" +
                                "Content-Type: text/html; charset=UTF-8\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length:   9\r\n" +
                                "Content-Type:   text/html; charset=UTF-8\r\n\r\n" +   // more than one SP after ':'
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length:\t10\r\n" +
                                "Content-Type:\ttext/html; charset=UTF-8\r\n\r\n" +   // HT separator
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length:\t\t10\r\n" +
                                "Content-Type:\t\ttext/html; charset=UTF-8\r\n\r\n" +   // more than one HT after ':'
                                "XXXXX",

                        "HTTP/1.1 407 Proxy Authorization Required\r\n" +
                                "Proxy-Authenticate: Basic realm=\"a fake realm\"\r\n\r\n",

                        "HTTP/1.1 401 Unauthorized\r\n" +
                                "WWW-Authenticate: Digest realm=\"wally land\" domain=/ " +
                                "nonce=\"2B7F3A2B\" qop=\"auth\"\r\n\r\n",

                        "HTTP/1.1 200 OK\r\n" +
                                "X-Foo:\r\n\r\n",      // no value

                        "HTTP/1.1 200 OK\r\n" +
                                "X-Foo:\r\n\r\n" +     // no value, with response body
                                "Some Response Body",

                        "HTTP/1.1 200 OK\r\n" +
                                "X-Foo:\r\n" +    // no value, followed by another header
                                "Content-Length: 10\r\n\r\n" +
                                "Some Response Body",

                        "HTTP/1.1 200 OK\r\n" +
                                "X-Foo:\r\n" +    // no value, followed by another header, with response body
                                "Content-Length: 10\r\n\r\n",

                        "HTTP/1.1 200 OK\r\n" +
                                "X-Foo: chegar\r\n" +
                                "X-Foo: dfuchs\r\n" +  // same header appears multiple times
                                "Content-Length: 0\r\n" +
                                "X-Foo: michaelm\r\n" +
                                "X-Foo: prappo\r\n\r\n",

                        "HTTP/1.1 200 OK\r\n" +
                                "X-Foo:\r\n" +    // no value, same header appears multiple times
                                "X-Foo: dfuchs\r\n" +
                                "Content-Length: 0\r\n" +
                                "X-Foo: michaelm\r\n" +
                                "X-Foo: prappo\r\n\r\n",

                        "HTTP/1.1 200 OK\r\n" +
                                "Accept-Ranges: bytes\r\n" +
                                "Cache-control: max-age=0, no-cache=\"set-cookie\"\r\n" +
                                "Content-Length: 132868\r\n" +
                                "Content-Type: text/html; charset=UTF-8\r\n" +
                                "Date: Sun, 05 Nov 2017 22:24:03 GMT\r\n" +
                                "Server: Apache/2.4.6 (Red Hat Enterprise Linux) OpenSSL/1.0.1e-fips Communique/4.2.2\r\n" +
                                "Set-Cookie: AWSELB=AF7927F5100F4202119876ED2436B5005EE;PATH=/;MAX-AGE=900\r\n" +
                                "Vary: Host,Accept-Encoding,User-Agent\r\n" +
                                "X-Mod-Pagespeed: 1.12.34.2-0\r\n" +
                                "Connection: keep-alive\r\n\r\n"
                };
        Arrays.stream(basic).forEach(responses::add);
        // add some tests where some of the CRLF are replaced
        // by a single LF
        Arrays.stream(basic)
                .map(HttpHeaderParserTest::mixedCRLF)
                .forEach(responses::add);

        String[] foldingTemplate =
                {  "HTTP/1.1 200 OK\r\n" +
                        "Content-Length: 9\r\n" +
                        "Content-Type: text/html;$NEWLINE" +  // folding field-value with '\n'|'\r'
                        " charset=UTF-8\r\n" +                // one preceding SP
                        "Connection: close\r\n\r\n" +
                        "XXYYZZAABBCCDDEE",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length: 19\r\n" +
                                "Content-Type: text/html;$NEWLINE" +  // folding field-value with '\n'|'\r
                                "   charset=UTF-8\r\n" +              // more than one preceding SP
                                "Connection: keep-alive\r\n\r\n" +
                                "XXYYZZAABBCCDDEEFFGG",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length: 999\r\n" +
                                "Content-Type: text/html;$NEWLINE" +  // folding field-value with '\n'|'\r
                                "\tcharset=UTF-8\r\n" +               // one preceding HT
                                "Connection: close\r\n\r\n" +
                                "XXYYZZAABBCCDDEE",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length: 54\r\n" +
                                "Content-Type: text/html;$NEWLINE" +  // folding field-value with '\n'|'\r
                                "\t\t\tcharset=UTF-8\r\n" +           // more than one preceding HT
                                "Connection: keep-alive\r\n\r\n" +
                                "XXYYZZAABBCCDDEEFFGG",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length: -1\r\n" +
                                "Content-Type: text/html;$NEWLINE" +  // folding field-value with '\n'|'\r
                                "\t \t \tcharset=UTF-8\r\n" +         // mix of preceding HT and SP
                                "Connection: keep-alive\r\n\r\n" +
                                "XXYYZZAABBCCDDEEFFGGHH",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length: 65\r\n" +
                                "Content-Type: text/html;$NEWLINE" +  // folding field-value with '\n'|'\r
                                " \t \t charset=UTF-8\r\n" +          // mix of preceding SP and HT
                                "Connection: keep-alive\r\n\r\n" +
                                "XXYYZZAABBCCDDEEFFGGHHII",

                        "HTTP/1.1 401 Unauthorized\r\n" +
                                "WWW-Authenticate: Digest realm=\"wally land\","
                                +"$NEWLINE    domain=/,"
                                +"$NEWLINE nonce=\"2B7F3A2B\","
                                +"$NEWLINE\tqop=\"auth\"\r\n\r\n",

                };
        for (String newLineChar : new String[] { "\n", "\r", "\r\n" }) {
            for (String template : foldingTemplate)
                responses.add(template.replace("$NEWLINE", newLineChar));
        }
        // add some tests where some of the CRLF are replaced
        // by a single LF
        for (String newLineChar : new String[] { "\n", "\r", "\r\n" }) {
            for (String template : foldingTemplate)
                responses.add(mixedCRLF(template).replace("$NEWLINE", newLineChar));
        }

        String[] bad = // much of this is to retain parity with legacy MessageHeaders
                { "HTTP/1.1 200 OK\r\n" +
                        "Connection:\r\n\r\n",   // empty value, no body

                        "HTTP/1.1 200 OK\r\n" +
                                "Connection:\r\n\r\n" +  // empty value, with body
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                ": no header\r\n\r\n",  // no/empty header-name, no body, no following header

                        "HTTP/1.1 200 OK\r\n" +
                                ": no; header\r\n" +  // no/empty header-name, no body, following header
                                "Content-Length: 65\r\n\r\n",

                        "HTTP/1.1 200 OK\r\n" +
                                ": no header\r\n" +  // no/empty header-name
                                "Content-Length: 65\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "X-foo: bar\r\n" +
                                " : no header\r\n" +  // fold, not a blank header-name
                                "Content-Length: 65\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "X-foo: bar\r\n" +
                                " \t : no header\r\n" +  // fold, not a blank header-name
                                "Content-Length: 65\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                ": no header\r\n\r\n" +  // no/empty header-name, followed by header
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "Conte\r" +
                                "nt-Length: 9\r\n" +    // fold/bad header name ??? without preceding space
                                "Content-Type: text/html; charset=UTF-8\r\n\r\n" +
                                "XXXXXYYZZ",

                        "HTTP/1.0 404 Not Found\r\n" +
                                "header-without-colon\r\n\r\n",

                        "HTTP/1.0 404 Not Found\r\n" +
                                "header-without-colon\r\n\r\n" +
                                "SOMEBODY",

                };
        Arrays.stream(bad).forEach(responses::add);

        return responses.stream().map(p -> new Object[] { p }).toArray(Object[][]::new);
    }

    static final AtomicInteger index = new AtomicInteger();
    static final AtomicInteger limit = new AtomicInteger(1);
    static final AtomicBoolean useCRLF = new AtomicBoolean();
    // A small method to replace part of the CRLF present in a string
    // with simple LF. The method uses a deterministic algorithm based
    // on current values of static index/limit/useCRLF counters.
    // These counters are used to produce a stream of substitutes that
    // looks like this:
    // LF CRLF LF LF CRLF CRLF LF LF LF CRLF CRLF CRLF (then repeat from start)
    static final String mixedCRLF(String headers) {
        int next;
        int start = 0;
        int last = headers.lastIndexOf("\r\n");
        String prev = "";
        StringBuilder res = new StringBuilder();
        while ((next = headers.indexOf("\r\n", start)) > 0) {
            res.append(headers.substring(start, next));
            if ("\n".equals(prev) && next == last) {
                // for some reason the legacy MessageHeader parser will
                // not consume the final LF if the headers are terminated
                // by <LF><CRLF> instead of <CRLF><CRLF>. It consume
                // <LF><CR> but leaves the last <LF> in the stream.
                // Here we just make sure to avoid using <LF><CRLF>
                // as that would cause the legacy parser to consume
                // 1 byte less than the Http1HeadersParser - which
                // does consume the last <LF>, as it should.
                // if this is the last CRLF and the previous one
                // was replaced by LF then use LF.
                res.append(prev);
            } else {
                prev = useCRLF.get() ? "\r\n" : "\n";
                res.append(prev);
            }
            // skip CRLF
            start = next + 2;

            // The idea is to substitute some of the CRLF with LF.
            // Rather than doing this randomly, always use the following
            // sequence:
            // LF CRLF LF LF CRLF CRLF LF LF LF CRLF CRLF CRLF
            index.incrementAndGet();
            if (index.get() == limit.get()) {
                index.set(0);
                if (useCRLF.get()) limit.incrementAndGet();
                if (limit.get() > 3) limit.set(1);
                useCRLF.set(!useCRLF.get());
            }
        }
        res.append(headers.substring(start));
        return res.toString();
    }


    @Test(dataProvider = "responses")
    public void verifyHeaders(String respString) throws Exception {
        System.out.println("\ntesting:\n\t" + respString
                .replace("\r\n", "<CRLF>")
                .replace("\r", "<CR>")
                .replace("\n","<LF>")
                .replace("LF>", "LF>\n\t"));
        byte[] bytes = respString.getBytes(ISO_8859_1);
        ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
        MessageHeader m = new MessageHeader(bais);
        Map<String,List<String>> messageHeaderMap = m.getHeaders();
        int availableBytes = bais.available();

        HttpHeaderParser decoder = new HttpHeaderParser();
        ByteArrayInputStream headerStream = new ByteArrayInputStream(bytes);
        int initialBytes = headerStream.available();
        decoder.parse(headerStream);
        System.out.printf("HttpHeaderParser parsed %d bytes out of %d%n", initialBytes - headerStream.available(), bytes.length);
        Map<String,List<String>> decoderMap1 = decoder.getHeaderMap();


        // assert status-line
        String statusLine1 = messageHeaderMap.get(null).get(0);
        String statusLine2 = decoder.getRequestDetails();
        if (statusLine1.startsWith("HTTP")) {// skip the case where MH's messes up the status-line
            assertEquals(statusLine2, statusLine1, "Status-line not equal");
        } else {
            assertTrue(statusLine2.startsWith("HTTP/1."), "Status-line not HTTP/1.");
        }

        // remove the null'th entry with is the status-line
        Map<String,List<String>> map = new HashMap<>();
        for (Map.Entry<String,List<String>> e : messageHeaderMap.entrySet()) {
            if (e.getKey() != null) {
                map.put(e.getKey(), e.getValue());
            }
        }
        messageHeaderMap = map;

        assertHeadersEqual(messageHeaderMap, decoderMap1,
                "messageHeaderMap not equal to decoderMap1");

        assertEquals(availableBytes, headerStream.available(),
                String.format("stream available (%d) not equal to remaining (%d)",
                        availableBytes, headerStream.available()));
    }

    @DataProvider(name = "errors")
    public Object[][] errors() {
        List<String> responses = new ArrayList<>();

        // These responses are parsed, somewhat, by MessageHeaders but give
        // nonsensible results. They, correctly, fail with the Http1HeaderParser.
        String[] bad =
                {// "HTTP/1.1 402 Payment Required\r\n" +
                        // "Content-Length: 65\r\n\r",   // missing trailing LF   //TODO: incomplete

                        "HTTP/1.1 402 Payment Required\r\n" +
                                "Content-Length: 65\r\n\rT\r\n\r\nGGGGGG",

                        "HTTP/1.1 200OK\r\n\rT",

                        "HTTP/1.1 200OK\rT",

                        "HTTP/1.0 FOO\r\n",

                        "HTTP/1.1 BAR\r\n",

                        "HTTP/1.1 +99\r\n",

                        "HTTP/1.1 -22\r\n",

                        "HTTP/1.1 -20 \r\n",

                        "HTTP/1.1 200 OK\r\n" +
                                "X-fo\u00ffo: foo\r\n" +     // invalid char in name
                                "Content-Length: 5\r\n" +
                                "Content-Type: text/html; charset=UTF-8\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "HTTP/1.1 200 OK\r\n" +
                                "X-foo : bar\r\n" +          //  trim space after name
                                "Content-Length: 5\r\n" +
                                "Content-Type: text/html; charset=UTF-8\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                " X-foo: bar\r\n" +          // trim space before name
                                "Content-Length: 5\r\n" +
                                "Content-Type: text/html; charset=UTF-8\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "X foo: bar\r\n" +           // invalid space in name
                                "Content-Length: 5\r\n" +
                                "Content-Type: text/html; charset=UTF-8\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "Content-Length: 5\r\n" +
                                "Content Type: text/html; charset=UTF-8\r\n\r\n" + // invalid space in name
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                "Conte\r" +
                                " nt-Length: 9\r\n" +    // fold results in space in header name
                                "Content-Type: text/html; charset=UTF-8\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                " : no header\r\n" +  // all blank header-name (not fold)
                                "Content-Length: 65\r\n\r\n" +
                                "XXXXX",

                        "HTTP/1.1 200 OK\r\n" +
                                " \t : no header\r\n" +  // all blank header-name (not fold)
                                "Content-Length: 65\r\n\r\n" +
                                "XXXXX",

                };
        Arrays.stream(bad).forEach(responses::add);

        return responses.stream().map(p -> new Object[] { p }).toArray(Object[][]::new);
    }

    @Test(dataProvider = "errors", expectedExceptions = IOException.class)
    public void errors(String respString) throws IOException {
        byte[] bytes = respString.getBytes(US_ASCII);
        HttpHeaderParser decoder = new HttpHeaderParser();
        ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
        decoder.parse(bais);
    }

    void assertHeadersEqual(Map<String,List<String>> expected,
                            Map<String,List<String>> actual,
                            String msg) {

        if (expected.equals(actual))
            return;

        assertEquals(expected.size(), actual.size(),
                format("%s. Expected size %d, actual size %s. %nexpected= %s,%n actual=%s.",
                        msg, expected.size(), actual.size(), mapToString(expected), mapToString(actual)));

        for (Map.Entry<String,List<String>> e : expected.entrySet()) {
            String key = e.getKey();
            List<String> values = e.getValue();

            boolean found = false;
            for (Map.Entry<String,List<String>> other: actual.entrySet()) {
                if (key.equalsIgnoreCase(other.getKey())) {
                    found = true;
                    List<String> otherValues = other.getValue();
                    assertEquals(values.size(), otherValues.size(),
                            format("%s. Expected list size %d, actual size %s",
                                    msg, values.size(), otherValues.size()));
                    if (!(values.containsAll(otherValues) && otherValues.containsAll(values)))
                        assertTrue(false, format("Lists are unequal [%s] [%s]", values, otherValues));
                    break;
                }
            }
            assertTrue(found, format("header name, %s, not found in %s", key, actual));
        }
    }

    static String mapToString(Map<String,List<String>> map) {
        StringBuilder sb = new StringBuilder();
        List<String> sortedKeys = new ArrayList(map.keySet());
        Collections.sort(sortedKeys);
        for (String key : sortedKeys) {
            List<String> values = map.get(key);
            sb.append("\n\t" + key + " | " + values);
        }
        return sb.toString();
    }
}