Migrate from "id" to "guid".

!!! ATTENTION !!! This change is NOT compatible to UPDATE exiting apps! + As of this commit the "id" XML attribute is no longer used as the unique token because its value cannot be guaranteed to be unique by the provider of the schedule XML. See voc/schedule#63. + Instead the "guid" XML attribute is used which guarantees unique values. + To keep this migration to a minimum only the value of the Session#sessionId field is changed. The value of the new primary key (auto-incrementing, unique through the "guid" column) is written into the "sessionId" field when a Session is queried from the database. See SessionsDatabaseRepository. + By this the value of the "id" XML attribute becomes unused hence the deprecation of the SESSION_ID database column.
EventFahrplan · Jul 30, 2021 · 1c895b3 · 1c895b3
1 parent 8ae1cfd
commit 1c895b3
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Showing 15 changed files with 68 additions and 27 deletions.
diff --git a/app/src/main/java/nerd/tuxmobil/fahrplan/congress/dataconverters/SessionExtensions.kt b/app/src/main/java/nerd/tuxmobil/fahrplan/congress/dataconverters/SessionExtensions.kt
@@ -34,6 +34,7 @@ fun Session.toHighlightDatabaseModel() = HighlightDatabaseModel(
 
 fun Session.toSessionDatabaseModel() = SessionDatabaseModel(
         sessionId = sessionId,
+        guid = guid,
         abstractt = abstractt,
         date = date,
         dateUTC = dateUTC,
@@ -75,6 +76,7 @@ fun Session.toSessionDatabaseModel() = SessionDatabaseModel(
 
 fun SessionDatabaseModel.toSessionAppModel(): Session {
     val session = Session(sessionId)
+    session.guid = guid
 
     session.abstractt = abstractt
     session.date = date
@@ -119,6 +121,7 @@ fun SessionDatabaseModel.toSessionAppModel(): Session {
 
 fun SessionNetworkModel.toSessionAppModel(): Session {
     val session = Session(sessionId)
+    session.guid = guid
 
     session.abstractt = abstractt
     session.date = date

diff --git a/app/src/main/java/nerd/tuxmobil/fahrplan/congress/models/Session.java b/app/src/main/java/nerd/tuxmobil/fahrplan/congress/models/Session.java
@@ -22,6 +22,9 @@
  */
 public class Session {
 
+    public String sessionId;
+    public String guid = "";
+
     public String title;
     public String subtitle;
     public String url;
@@ -46,7 +49,6 @@ public class Session {
 
     public String speakers;
     public String track;
-    public String sessionId;
     public String type;
     public String lang;
     public String slug;
@@ -80,6 +82,7 @@ public class Session {
     private static final boolean RECORDING_OPTOUT_OFF = false;
 
     public Session(String sessionId) {
+        guid = "";
         title = "";
         subtitle = "";
         day = 0;
@@ -119,6 +122,7 @@ public Session(String sessionId) {
     }
 
     public Session(@NonNull Session session) {
+        this.guid = session.guid;
         this.title = session.title;
         this.subtitle = session.subtitle;
         this.url = session.url;
@@ -208,6 +212,7 @@ public boolean equals(Object o) {
         if (!ObjectsCompat.equals(date, session.date)) return false;
         if (!ObjectsCompat.equals(lang, session.lang)) return false;
         if (!sessionId.equals(session.sessionId)) return false;
+        if (!guid.equals(session.guid)) return false;
         if (!ObjectsCompat.equals(recordingLicense, session.recordingLicense)) return false;
         if (!ObjectsCompat.equals(room, session.room)) return false;
         if (!ObjectsCompat.equals(speakers, session.speakers)) return false;
@@ -232,6 +237,7 @@ public int hashCode() {
         result = 31 * result + ObjectsCompat.hashCode(speakers);
         result = 31 * result + ObjectsCompat.hashCode(track);
         result = 31 * result + sessionId.hashCode();
+        result = 31 * result + guid.hashCode();
         result = 31 * result + ObjectsCompat.hashCode(type);
         result = 31 * result + ObjectsCompat.hashCode(lang);
         result = 31 * result + ObjectsCompat.hashCode(date);

diff --git a/app/src/main/java/nerd/tuxmobil/fahrplan/congress/repositories/AppRepository.kt b/app/src/main/java/nerd/tuxmobil/fahrplan/congress/repositories/AppRepository.kt
@@ -398,9 +398,9 @@ object AppRepository {
 
     private fun updateSessions(toBeUpdatedSessions: List<Session>, toBeDeletedSessions: List<Session> = emptyList()) {
         val toBeUpdatedSessionsDatabaseModel = toBeUpdatedSessions.toSessionsDatabaseModel()
-        val toBeUpdated = toBeUpdatedSessionsDatabaseModel.map { it.sessionId to it.toContentValues() }
-        val toBeDeleted = toBeDeletedSessions.map { it.sessionId }
-        sessionsDatabaseRepository.updateSessions(toBeUpdated, toBeDeleted)
+        val toBeUpdated = toBeUpdatedSessionsDatabaseModel.map { it.guid to it.toContentValues() }
+        val toBeDeleted = toBeDeletedSessions.map { it.guid }
+        sessionsDatabaseRepository.upsertSessions(toBeUpdated, toBeDeleted)
     }
 
     /**

diff --git a/app/src/main/java/nerd/tuxmobil/fahrplan/congress/serialization/ScheduleChanges.kt b/app/src/main/java/nerd/tuxmobil/fahrplan/congress/serialization/ScheduleChanges.kt
@@ -41,7 +41,7 @@ data class ScheduleChanges private constructor(
             var sessionIndex = 0
             while (sessionIndex < newSessions.size) {
                 val newSession = newSessions[sessionIndex]
-                val oldSession = oldNotCanceledSessions.singleOrNull { oldNotCanceledSession -> newSession.sessionId == oldNotCanceledSession.sessionId }
+                val oldSession = oldNotCanceledSessions.singleOrNull { oldNotCanceledSession -> newSession.guid == oldNotCanceledSession.guid }
                 if (oldSession == null) {
                     sessionsWithChangeFlags += SessionAppModel(newSession).apply { changedIsNew = true }
                     foundChanges = true

diff --git a/app/src/test/java/nerd/tuxmobil/fahrplan/congress/dataconverters/SessionExtensionsTest.kt b/app/src/test/java/nerd/tuxmobil/fahrplan/congress/dataconverters/SessionExtensionsTest.kt
@@ -18,6 +18,7 @@ class SessionExtensionsTest {
     fun sessionDatabaseModel_toSessionAppModel_toSessionDatabaseModel() {
         val session = SessionDatabaseModel(
                 sessionId = "7331",
+                guid = "11111111-1111-1111-1111-111111111111",
                 abstractt = "Lorem ipsum",
                 dayIndex = 3,
                 date = "2015-08-13",
@@ -63,6 +64,7 @@ class SessionExtensionsTest {
     fun sessionNetworkModel_toSessionAppModel() {
         val sessionNetworkModel = SessionNetworkModel(
                 sessionId = "7331",
+                guid = "11111111-1111-1111-1111-111111111111",
                 abstractt = "Lorem ipsum",
                 dayIndex = 3,
                 date = "2015-08-13",
@@ -102,6 +104,7 @@ class SessionExtensionsTest {
                 changedTrack = true
         )
         val sessionAppModel = SessionAppModel("7331").apply {
+            guid = "11111111-1111-1111-1111-111111111111"
             abstractt = "Lorem ipsum"
             day = 3
             date = "2015-08-13"

diff --git a/app/src/test/java/nerd/tuxmobil/fahrplan/congress/models/SessionTest.kt b/app/src/test/java/nerd/tuxmobil/fahrplan/congress/models/SessionTest.kt
@@ -10,6 +10,7 @@ class SessionTest {
     companion object {
 
         fun createSession() = Session("s1").apply {
+            guid = "11111111-1111-1111-1111-111111111111"
             title = "Lorem ipsum"
             subtitle = "Gravida arcu ac tortor"
             day = 3

diff --git a/app/src/test/java/nerd/tuxmobil/fahrplan/congress/serialization/ScheduleChangesTest.kt b/app/src/test/java/nerd/tuxmobil/fahrplan/congress/serialization/ScheduleChangesTest.kt
@@ -276,6 +276,11 @@ class ScheduleChangesTest {
         assertThat(scheduleChanges.foundChanges).isTrue()
     }
 
-    private fun createSession(sessionId: String = "1", block: Session.() -> Unit = {}) = Session(sessionId).apply(block)
+    private fun createSession(sessionId: String = "1", block: Session.() -> Unit = {}): Session {
+        return Session(sessionId).apply {
+            guid = sessionId // shortcut for testing purpose only!
+            block()
+        }
+    }
 
 }
diff --git a/...est/java/info/metadude/android/eventfahrplan/database/extensions/SessionExtensionsTest.kt b/...est/java/info/metadude/android/eventfahrplan/database/extensions/SessionExtensionsTest.kt
@@ -14,6 +14,7 @@ class SessionExtensionsTest {
     fun toContentValues() {
         val session = Session(
                 sessionId = "7331",
+                guid = "11111111-1111-1111-1111-111111111111",
                 abstractt = "Lorem ipsum",
                 dayIndex = 3,
                 date = "2015-08-13",
@@ -53,6 +54,7 @@ class SessionExtensionsTest {
         )
         val values = session.toContentValues()
         assertThat(values.getAsInteger(SESSION_ID)).isEqualTo(7331)
+        assertThat(values.getAsString(GUID)).isEqualTo("11111111-1111-1111-1111-111111111111")
         assertThat(values.getAsString(ABSTRACT)).isEqualTo("Lorem ipsum")
         assertThat(values.getAsInteger(DAY)).isEqualTo(3)
         assertThat(values.getAsString(DATE)).isEqualTo("2015-08-13")

diff --git a/...src/main/java/info/metadude/android/eventfahrplan/database/contract/FahrplanContract.java b/...src/main/java/info/metadude/android/eventfahrplan/database/contract/FahrplanContract.java
@@ -89,6 +89,7 @@ interface SessionsTable {
 
         interface Columns extends BaseColumns {
 
+            @Deprecated // Value is unused. Query primary key _ID column instead.
             /* 00 */ String SESSION_ID = "event_id"; // Keep column name to avoid database migration.
             /* 01 */ String TITLE = "title";
             /* 02 */ String SUBTITLE = "subtitle";
@@ -124,6 +125,7 @@ interface Columns extends BaseColumns {
             /* 32 */ String SLUG = "slug";
             /* 33 */ String URL = "url";
             /* 34 */ String TIME_ZONE_OFFSET = "time_zone_offset";
+            /* 35 */ String GUID = "guid";
         }
 
         interface Defaults {

diff --git a/...rc/main/java/info/metadude/android/eventfahrplan/database/extensions/SessionExtensions.kt b/...rc/main/java/info/metadude/android/eventfahrplan/database/extensions/SessionExtensions.kt
@@ -21,6 +21,7 @@ import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.Se
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.DAY
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.DESCR
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.DURATION
+import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.GUID
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.LANG
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.LINKS
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.REC_LICENSE
@@ -44,6 +45,7 @@ import info.metadude.android.eventfahrplan.database.models.Session
 
 fun Session.toContentValues() = contentValuesOf(
         SESSION_ID to sessionId,
+        GUID to guid,
         ABSTRACT to abstractt,
         DAY to dayIndex,
         DATE to date,

diff --git a/database/src/main/java/info/metadude/android/eventfahrplan/database/models/Session.kt b/database/src/main/java/info/metadude/android/eventfahrplan/database/models/Session.kt
@@ -6,6 +6,7 @@ package info.metadude.android.eventfahrplan.database.models
 data class Session(
 
         val sessionId: String,
+        val guid: String,
         val abstractt: String = "",
         val dayIndex: Int = 0,
         val date: String = "",

diff --git a/...a/info/metadude/android/eventfahrplan/database/repositories/SessionsDatabaseRepository.kt b/...a/info/metadude/android/eventfahrplan/database/repositories/SessionsDatabaseRepository.kt
@@ -26,14 +26,14 @@ import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.Se
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.DAY
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.DESCR
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.DURATION
+import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.GUID
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.LANG
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.LINKS
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.REC_LICENSE
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.REC_OPTOUT
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.REL_START
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.ROOM
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.ROOM_IDX
-import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.SESSION_ID
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.SLUG
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.SPEAKERS
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.START
@@ -43,6 +43,7 @@ import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.Se
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.TRACK
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.TYPE
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns.URL
+import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Columns._ID
 import info.metadude.android.eventfahrplan.database.contract.FahrplanContract.SessionsTable.Values.REC_OPT_OUT_OFF
 import info.metadude.android.eventfahrplan.database.extensions.delete
 import info.metadude.android.eventfahrplan.database.extensions.getInt
@@ -88,36 +89,39 @@ class SessionsDatabaseRepository(
 
 
     /**
-     * Updates or inserts sessions based on the given [contentValuesBySessionId].
-     * Removes all sessions identified by their [session IDs][toBeDeletedSessionIds].
+     * Updates or inserts sessions based on the given [contentValuesByGuid].
+     * Removes all sessions identified by their [session GUIDs][toBeDeletedSessionGuids].
      */
-    fun updateSessions(
-            contentValuesBySessionId: List<Pair</* sessionId */ String, ContentValues>>,
-            toBeDeletedSessionIds: List</* sessionId */ String>
+    fun upsertSessions(
+        contentValuesByGuid: List<Pair</* guid */ String, ContentValues>>,
+        toBeDeletedSessionGuids: List</* sessionGuid */ String>
     ) = with(sqLiteOpenHelper) {
         writableDatabase.transaction {
-            contentValuesBySessionId.forEach { (sessionId, contentValues) ->
-                upsertSession(sessionId, contentValues)
+            contentValuesByGuid.forEach { (guid, contentValues) ->
+                upsertSession(guid, contentValues)
             }
-            toBeDeletedSessionIds.forEach { toBeDeletedSessionId ->
-                deleteSession(toBeDeletedSessionId)
+            toBeDeletedSessionGuids.forEach { toBeDeletedSessionGuid ->
+                deleteSession(toBeDeletedSessionGuid)
             }
         }
     }
 
     /**
-     * Updates a session with the given [contentValues]. A row is matched by its [sessionId].
+     * Updates a session with the given [contentValues]. A row is matched by its [guid].
      * If no row was affected by the update operation then an insert operation is performed
      * assuming that the session does not exist in the table.
      *
+     * The [guid] column is used for matching an existing row because this column holds unique values
+     * and to avoid an unneeded database SELECT just to retrieve the primary key of a row.
+     *
      * This function must be called in the context of a [transaction] block.
      */
-    private fun SQLiteDatabase.upsertSession(sessionId: String, contentValues: ContentValues) {
+    private fun SQLiteDatabase.upsertSession(guid: String, contentValues: ContentValues) {
         val affectedRowsCount = updateRow(
                 tableName = SessionsTable.NAME,
                 contentValues = contentValues,
-                columnName = SESSION_ID,
-                columnValue = sessionId
+                columnName = GUID,
+                columnValue = guid
         )
         if (affectedRowsCount == 0) {
             insert(
@@ -128,19 +132,21 @@ class SessionsDatabaseRepository(
     }
 
     /**
-     * Delete the session identified by the given [sessionId] from the table.
+     * Delete the session identified by the given [sessionGuid] from the table.
      */
-    private fun SQLiteDatabase.deleteSession(sessionId: String) = delete(
+    private fun SQLiteDatabase.deleteSession(sessionGuid: String) = delete(
             tableName = SessionsTable.NAME,
-            columnName = SESSION_ID,
-            columnValue = sessionId
+            columnName = GUID,
+            columnValue = sessionGuid
     )
 
     fun querySessionBySessionId(sessionId: String): Session {
         return try {
             query {
                 read(SessionsTable.NAME,
-                        selection = "$SESSION_ID=?",
+                        // The value of "sessionId" is replaced with the value of the "_id"
+                        // column when the session is queried initially to guarantee a unique value.
+                        selection = "$_ID=?",
                         selectionArgs = arrayOf(sessionId))
             }.first()
         } catch (e: NoSuchElementException) {
@@ -192,7 +198,11 @@ class SessionsDatabaseRepository(
                         Session.RECORDING_OPT_OUT_ON
 
             Session(
-                    sessionId = cursor.getString(SESSION_ID),
+                    // The value of the auto-incrementing primary key "_id" column is written as
+                    // the value of the "sessionId" field as the first step to rely on the "guid"
+                    // column. It has a unique value which is not guaranteed by "sessionId".
+                    sessionId = "${cursor.getLong(_ID)}",
+                    guid = cursor.getString(GUID),
                     abstractt = cursor.getString(ABSTRACT),
                     date = cursor.getString(DATE),
                     dateUTC = cursor.getLong(DATE_UTC),

diff --git a/...a/info/metadude/android/eventfahrplan/database/sqliteopenhelper/SessionsDBOpenHelper.java b/...a/info/metadude/android/eventfahrplan/database/sqliteopenhelper/SessionsDBOpenHelper.java
@@ -21,7 +21,9 @@ public class SessionsDBOpenHelper extends SQLiteOpenHelper {
 
     private static final String SESSIONS_TABLE_CREATE =
             "CREATE TABLE " + SessionsTable.NAME + " (" +
+                    BaseColumns._ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
                     Columns.SESSION_ID + " TEXT, " +
+                    Columns.GUID + " TEXT NOT NULL UNIQUE, " +
                     Columns.TITLE + " TEXT, " +
                     Columns.SUBTITLE + " TEXT, " +
                     Columns.DAY + " INTEGER, " +

diff --git a/network/src/main/java/info/metadude/android/eventfahrplan/network/models/Session.kt b/network/src/main/java/info/metadude/android/eventfahrplan/network/models/Session.kt
@@ -9,6 +9,8 @@ import info.metadude.android.eventfahrplan.network.serialization.FahrplanParser
 data class Session(
 
         var sessionId: String = "",
+        var guid: String = "",
+
         var abstractt: String = "",
         var dayIndex: Int = 0,
         var date: String = "",

diff --git a/...c/main/java/info/metadude/android/eventfahrplan/network/serialization/FahrplanParser.java b/...c/main/java/info/metadude/android/eventfahrplan/network/serialization/FahrplanParser.java
@@ -13,8 +13,8 @@
 import java.util.List;
 
 import info.metadude.android.eventfahrplan.commons.logging.Logging;
-import info.metadude.android.eventfahrplan.network.models.Session;
 import info.metadude.android.eventfahrplan.network.models.Meta;
+import info.metadude.android.eventfahrplan.network.models.Session;
 import info.metadude.android.eventfahrplan.network.serialization.exceptions.MissingXmlAttributeException;
 import info.metadude.android.eventfahrplan.network.temporal.DateParser;
 import info.metadude.android.eventfahrplan.network.validation.DateFieldValidation;
@@ -173,8 +173,10 @@ private Boolean parseFahrplan(String fahrplan, String eTag) {
                         }
                         if (name.equalsIgnoreCase("event")) {
                             String id = parser.getAttributeValue(null, "id");
+                            String guid = parser.getAttributeValue(null, "guid");
                             Session session = new Session();
                             session.setSessionId(id);
+                            session.setGuid(guid);
                             session.setDayIndex(day);
                             session.setRoom(room);
                             session.setDate(date);