W9RvXTtJ

1package org.diablitozzz.backend.db.pg;
2
3import java.net.URI;
4import java.nio.charset.StandardCharsets;
5import java.util.HashSet;
6import java.util.List;
7import java.util.Set;
8import java.util.stream.Collectors;
9
10import javax.annotation.concurrent.ThreadSafe;
11
12import org.diablitozzz.backend.db.Db;
13import org.diablitozzz.backend.db.DbException;
14import org.diablitozzz.backend.db.DbVersions;
15import org.diablitozzz.backend.utils.ClassLoaderUtils;
16import org.diablitozzz.backend.utils.IOUtils;
17import org.diablitozzz.backend.utils.ObjectUtils;
18
19@ThreadSafe
20public class DbVersionsPg implements DbVersions {
21
22    protected static class Version implements Comparable<Version> {
23
24        public final long version;
25        public final URI uri;
26
27        public Version(final URI uri, final long version) {
28            this.uri = uri;
29            this.version = version;
30        }
31
32        @Override
33        public int compareTo(final Version o) {
34            return Long.compare(version, o.version);
35        }
36
37        @Override
38        public boolean equals(final Object obj) {
39            return ObjectUtils.equals(this, obj, b -> ObjectUtils.equals(version, b.version));
40        }
41
42        @Override
43        public int hashCode() {
44            return ObjectUtils.hashCode(version);
45        }
46
47        public String loadContent() throws Exception {
48            final byte[] blob = IOUtils.inputStreamToByteArray(uri.toURL().openStream(), 1024 * 1024);
49            return new String(blob, StandardCharsets.UTF_8).trim();
50        }
51
52        @Override
53        public String toString() {
54            return uri.toString();
55        }
56
57    }
58
59    private final Db db;
60    private final String path;
61    private final String tableName;
62
63    public DbVersionsPg(final Db db, final String tableName, final String path) {
64        this.db = db;
65        this.path = path;
66        this.tableName = tableName;
67    }
68
69    @Override
70    public void close() {
71    }
72
73    public Set<Version> loadVersions() throws Exception {
74
75        final Set<URI> uris = ClassLoaderUtils.listResourceDir(Thread.currentThread().getContextClassLoader(), path);
76        final Set<Version> versions = new HashSet<>(64);
77        for (final URI uri : uris) {
78            if (uri.getPath().endsWith("/")) {
79                continue;
80            }
81            final String[] items = uri.toURL().toExternalForm().split("/");
82            final String file = items[items.length - 1];
83            final long version = Long.valueOf(file.split("[\\.\\-\\_]")[0].trim());
84            versions.add(new Version(uri, version));
85        }
86        return versions;
87    }
88
89    @Override
90    public void up() throws DbException {
91        try {
92
93            db.exec(ctx -> ctx.exec(String.format(
94                "CREATE TABLE IF NOT EXISTS %s (version bigint NOT NULL PRIMARY KEY,created timestamp(0) with time zone NOT NULL DEFAULT now())",
95                tableName)));
96
97            final long lastVersion = db.select(ctx -> ctx
98                .select(String.format("SELECT COALESCE((SELECT MAX(version) FROM %s), 0)", tableName))
99                .first()
100                .get(0, Long.class));
101
102            final List<Version> versionsForUp = loadVersions().stream()
103                .filter(v -> lastVersion == 0 ? true : v.version > lastVersion)
104                .sorted()
105                .collect(Collectors.toList());
106
107            for (final Version version : versionsForUp) {
108                db.execT(ctx -> {
109                    ctx.exec(version.loadContent());
110                    ctx.exec(String.format("INSERT INTO %s (version,created) VALUES(?, NOW())", tableName), version.version);
111                });
112            }
113        } catch (final Exception e) {
114            throw DbException.create(e);
115        }
116    }
117
118}