Dépôt officiel du code source de l'ERP OpenConcerto

/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

 *

 * Copyright 2011-2019 OpenConcerto, by ILM Informatique. All rights reserved.

 *

 * The contents of this file are subject to the terms of the GNU General Public License Version 3

 * only ("GPL"). You may not use this file except in compliance with the License. You can obtain a

 * copy of the License at http://www.gnu.org/licenses/gpl-3.0.html See the License for the specific

 * language governing permissions and limitations under the License.

 *

 * When distributing the software, include this License Header Notice in each file.

 */

 package org.openconcerto.utils.sync;

import org.openconcerto.utils.CollectionUtils;

import org.openconcerto.utils.MessageDigestUtils;

import org.openconcerto.utils.NetUtils;

import org.openconcerto.utils.StreamUtils;

import org.openconcerto.utils.net.HTTPClient;

import java.io.BufferedInputStream;

import java.io.BufferedOutputStream;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.io.Serializable;

import java.nio.charset.StandardCharsets;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.StandardCopyOption;

import java.nio.file.attribute.FileTime;

import java.security.DigestOutputStream;

import java.security.MessageDigest;

import java.time.Instant;

import java.util.ArrayList;

import java.util.Base64;

import java.util.Collections;

import java.util.List;

import java.util.Set;

import java.util.concurrent.atomic.AtomicBoolean;

import java.util.function.BiFunction;

import java.util.function.Predicate;

import javax.net.ssl.HttpsURLConnection;

import net.minidev.json.JSONArray;

import net.minidev.json.JSONObject;

import net.minidev.json.parser.JSONParser;

public final class SimpleSyncClient extends HTTPClient {

    protected static final long getLong(final Object o) {

        return ((Number) o).longValue();

    }

    protected static final Instant getInstant(final Object o) {

        return Instant.ofEpochMilli(getLong(o));

    }

    public static abstract class BaseAttrs implements Serializable {

        private final String path;

        private final String name;

        private final Instant lastModified;

        protected BaseAttrs(final String path, final String name, final Instant lastModified) {

            super();

            this.path = path;

            this.name = name;

            this.lastModified = lastModified;

        }

        public final String getPath() {

            return this.path;

        }

        public final String getName() {

            return this.name;

        }

        public final Instant getLastModified() {

            return this.lastModified;

        }

        @Override

        public String toString() {

            return this.getClass().getSimpleName() + " '" + this.getName() + "'";

        }

    }

    public static final class DirAttrs extends BaseAttrs {

        protected static DirAttrs fromJSON(final String path, final JSONArray array) {

            return new DirAttrs(path, (String) array.get(0), getInstant(array.get(1)));

        }

        protected DirAttrs(final String path, String name, Instant lastModified) {

            super(path, name, lastModified);

        }

    }

    public static final class FileAttrs extends BaseAttrs {

        protected static FileAttrs fromJSON(final String path, final JSONArray array) {

            return new FileAttrs(path, (String) array.get(0), getInstant(array.get(2)), getLong(array.get(1)), (String) array.get(3));

        }

        private final long size;

        private final String sha256;

        protected FileAttrs(final String path, String name, Instant lastModified, long size, String sha256) {

            super(path, name, lastModified);

            this.size = size;

            this.sha256 = sha256;

        }

        public final long getSize() {

            return this.size;

        }

        public final String getSHA256() {

            return this.sha256;

        }

        public final void saveFile(final InputStream in, final Path localFile) throws IOException {

            // Save to temporary file to avoid overwriting old file with a new invalid one. In

            // same folder for the move.

            final Path tmpFile = Files.createTempFile(localFile.getParent(), "partial", null);

            try {

                final MessageDigest md = this.getSHA256() == null ? null : MessageDigestUtils.getSHA256();

                try (final BufferedOutputStream fileStream = new BufferedOutputStream(Files.newOutputStream(tmpFile));

                        //

                        final OutputStream out = md == null ? fileStream : new DigestOutputStream(fileStream, md)) {

                    StreamUtils.copy(in, out);

                }

                if (this.getSize() >= 0) {

                    final long savedSize = Files.size(tmpFile);

                    if (savedSize != this.getSize())

                        throw new IOException("Expected " + this.getSize() + " bytes but saved " + savedSize);

                }

                if (md != null) {

                    final String savedHash = MessageDigestUtils.getHashString(md);

                    if (!savedHash.equalsIgnoreCase(this.getSHA256()))

                        throw new IOException("Expected hash was " + this.getSHA256() + " but saved " + savedHash);

                }

                Files.move(tmpFile, localFile, StandardCopyOption.REPLACE_EXISTING);

            } finally {

                Files.deleteIfExists(tmpFile);

            }

            if (this.getLastModified().compareTo(Instant.EPOCH) > 0)

                Files.setLastModifiedTime(localFile, FileTime.from(this.getLastModified()));

        }

        @Override

        public String toString() {

            return super.toString() + " of size " + getSize();

        }

    }

    public static final class DirContent {

        private final String path;

        private final JSONObject json;

        protected DirContent(final String path, JSONObject json) {

            super();

            this.path = path;

            this.json = json;

        }

        public final List<FileAttrs> getFiles() {

            return this.getFiles(null);

        }

        public final List<FileAttrs> getFiles(final Predicate<String> namePredicate) {

            return this.getContent("files", namePredicate, FileAttrs::fromJSON);

        }

        public final List<DirAttrs> getDirs() {

            return this.getDirs(null);

        }

        public final List<DirAttrs> getDirs(final Predicate<String> namePredicate) {

            return this.getContent("dirs", namePredicate, DirAttrs::fromJSON);

        }

        protected final <T extends BaseAttrs> List<T> getContent(final String key, final Predicate<String> namePredicate, final BiFunction<String, JSONArray, T> create) {

            final JSONArray files = (JSONArray) this.json.get(key);

            if (files == null)

                return Collections.emptyList();

            final List<T> res = new ArrayList<>();

            for (final Object f : files) {

                final JSONArray array = (JSONArray) f;

                if (namePredicate == null || namePredicate.test((String) array.get(0))) {

                    res.add(create.apply(this.path, array));

                }

            }

            return res;

        }

    }

    public SimpleSyncClient(final String url) {

        super(url);

    }

    public DirContent getDir(final String path) throws Exception {

        if (path == null) {

            throw new IllegalArgumentException("null path");

        }

        final HttpsURLConnection con = openConnection("/getDir");

        final Response res = checkResponseCode(send(con, NetUtils.urlEncode("rp", path, "type", "json"), false));

        if (!res.isSuccess())

            return null;

        final JSONParser p = new JSONParser(JSONParser.MODE_STRICTEST);

        try (final InputStream in = getInputStream(con)) {

            return new DirContent(path, (JSONObject) p.parse(in));

        }

    }

    @FunctionalInterface

    public static interface FileConsumer {

        public void accept(FileAttrs attrs, InputStream fileStream) throws IOException;

    }

    private static final Set<Integer> GETFILE_OK_CODES = CollectionUtils.createSet(200, 404);

    public Response getFile(final String path, final String fileName, final FileConsumer fileConsumer) throws IOException {

        if (path == null) {

            throw new IllegalArgumentException("null path");

        }

        if (fileName == null) {

            throw new IllegalArgumentException("null fileName");

        }

        final HttpsURLConnection con = openConnection("/get");

        send(con, NetUtils.urlEncode("rn", fileName, "rp", path), false);

        final Response res = checkResponseCode(con, GETFILE_OK_CODES);

        if (res.getCode() == 404) {

            fileConsumer.accept(null, null);

        } else if (res.getCode() == 200) {

            final FileAttrs fileAttrs = new FileAttrs(path, fileName, Instant.ofEpochMilli(con.getLastModified()), -1, con.getHeaderField("X-SHA256"));

            try (final InputStream in = getInputStream(con)) {

                fileConsumer.accept(fileAttrs, in);

            }

        }

        return res;

    }

    public Integer getCounter(final String key) throws IOException {

        if (key == null) {

            throw new IllegalArgumentException("null key");

        }

        final HttpsURLConnection con = openConnection("/getCounter");

        send(con, NetUtils.urlEncode("key", key), false);

        final Response res = checkResponseCode(con, GETFILE_OK_CODES);

        if (res.getCode() == 200) {

            byte[] bytes = new byte[20];

            try (final InputStream in = getInputStream(con)) {

                int r = in.read(bytes);

                String str = new String(bytes, 0, r);

                return Integer.parseInt(str);

            }

        }

        return null;

    }

    // ATTN contrary to other methods, the result isn't if the request was OK : it ignores

    // throwsException() and always throws. The return value is true if the file existed and was

    // saved.

    public boolean saveFile(final String path, final String fileName, final Path localFile) throws IOException {

        if (path == null) {

            throw new IllegalArgumentException("null path");

        }

        if (fileName == null) {

            throw new IllegalArgumentException("null fileName");

        }

        final AtomicBoolean missing = new AtomicBoolean(true);

        final Response res = this.getFile(path, fileName, (fileAttrs, in) -> {

            missing.set(fileAttrs == null);

            if (!missing.get()) {

                fileAttrs.saveFile(in, localFile);

            }

        });

        if (!res.isSuccess())

            throw new IOException("Couldn't retrieve file " + fileName);

        return !missing.get();

    }

    public Response deleteFile(final String path, final String fileName) throws IOException {

        if (path == null) {

            throw new IllegalArgumentException("null path");

        }

        if (fileName == null) {

            throw new IllegalArgumentException("null fileName");

        }

        final HttpsURLConnection con = openConnection("/delete");

        return checkResponseCode(send(con, NetUtils.urlEncode("rn", fileName, "rp", path), false));

    }

    public final Response renameFile(final String path, final String fileName, final String newFileName) throws IOException {

        return this.renameFile(path, fileName, path, newFileName);

    }

    public final Response renameFile(final String path, final String fileName, final String newPath, final String newFileName) throws IOException {

        if (path == null) {

            throw new IllegalArgumentException("null path");

        }

        if (fileName == null) {

            throw new IllegalArgumentException("null fileName");

        }

        if (newPath == null) {

            throw new IllegalArgumentException("null newPath");

        }

        if (newFileName == null) {

            throw new IllegalArgumentException("null newFileName");

        }

        final HttpsURLConnection con = openConnection("/rename");

        return checkResponseCode(send(con, NetUtils.urlEncode("rn", fileName, "rp", path, "newPath", newPath, "newName", newFileName), false));

    }

    public Response sendFile(String path, File localFile) throws IOException {

        return this.sendFile(path, localFile, false);

    }

    public Response sendFile(String path, File localFile, final boolean overwrite) throws IOException {

        if (path == null) {

            throw new IllegalArgumentException("null path");

        }

        final long size = localFile.length();

        if (size >= Integer.MAX_VALUE)

            throw new OutOfMemoryError("Required array size too large : " + size);

        final ByteArrayOutputStream ba = new ByteArrayOutputStream((int) size);

        final byte[] newsha256;

        // compute digest at the same time to protect against race conditions

        try (final InputStream ins = new BufferedInputStream(new FileInputStream(localFile))) {

            newsha256 = MessageDigestUtils.getHash(MessageDigestUtils.getSHA256(), ins, ba);

        }

        final HttpsURLConnection con = openConnection("/put");

        // We use Base64 because headers are not supporting UTF8

        con.setRequestProperty("X_FILENAME_B64", Base64.getEncoder().encodeToString(localFile.getName().getBytes(StandardCharsets.UTF_8)));

        con.setRequestProperty("X_PATH_B64", Base64.getEncoder().encodeToString(path.getBytes(StandardCharsets.UTF_8)));

        con.setRequestProperty("X-OVERWRITE", Boolean.toString(overwrite));

        con.setRequestProperty("X_FILESIZE", String.valueOf(size));

        con.setRequestProperty("X_SHA256", HashWriter.bytesToHex(newsha256));

        con.setRequestProperty("X-Last-Modified-ms", String.valueOf(localFile.lastModified()));

        return checkResponseCode(send(con, ba.toByteArray(), true));

    }

    public Response createDir(String path, String fileName) throws IOException {

        if (path == null) {

            throw new IllegalArgumentException("null path");

        }

        if (fileName == null) {

            throw new IllegalArgumentException("null fileName");

        }

        final HttpsURLConnection con = openConnection("/mkdir");

        return checkResponseCode(send(con, NetUtils.urlEncode("rn", fileName, "rp", path), false));

    }

}