make IM messages and chats persistent in the database.

They used to be in memory portion of the database, and are wiped when the device reboots or the android.acore process dies. We are trying to make them more resilient to process dying, as well as trying to retain longer message history.

updated database version, implemented upgrade path (creating Messages and Chats tables in persistent store).

added back the trigger to delete chat when a contact is deleted.

1 files changed, 115 insertions, 63 deletions

diff --git a/src/com/android/providers/im/ImProvider.java b/src/com/android/providers/im/ImProvider.java
index 319a197..a0d1d15 100644
--- a/src/com/android/providers/im/ImProvider.java
+++ b/src/com/android/providers/im/ImProvider.java
@@ -49,7 +49,7 @@ public class ImProvider extends ContentProvider {
 
     private static final String AUTHORITY = "im";
 
-    private static final boolean USE_CONTACT_PRESENCE_TRIGGER = false;
+    private static final boolean MAKE_MESSAGE_PRESENCE_CHAT_PERSISTENT = true;
 
     private static final String TABLE_ACCOUNTS = "accounts";
     private static final String TABLE_PROVIDERS = "providers";
@@ -74,7 +74,7 @@ public class ImProvider extends ContentProvider {
     private static final String TABLE_BRANDING_RESOURCE_MAP_CACHE = "brandingResMapCache";
 
     private static final String DATABASE_NAME = "im.db";
-    private static final int DATABASE_VERSION = 47;
+    private static final int DATABASE_VERSION = 48;
 
     protected static final int MATCH_PROVIDERS = 1;
     protected static final int MATCH_PROVIDERS_BY_ID = 2;
@@ -226,6 +226,7 @@ public class ImProvider extends ContentProvider {
                     ");");
 
             createContactsTables(db);
+            createMessageChatTables(db, null /* no table prefix */);
 
             db.execSQL("CREATE TABLE " + TABLE_AVATARS + " (" +
                     "_id INTEGER PRIMARY KEY," +
@@ -352,6 +353,24 @@ public class ImProvider extends ContentProvider {
                         db.endTransaction();
                     }
 
+                case 47:
+                    if (newVersion <= 47) {
+                        return;
+                    }
+
+                    if (MAKE_MESSAGE_PRESENCE_CHAT_PERSISTENT) {
+                        db.beginTransaction();
+                        try {
+                            createMessageChatTables(db, null);
+                            db.setTransactionSuccessful();
+                        } catch (Throwable ex) {
+                            Log.e(LOG_TAG, ex.getMessage(), ex);
+                            break; // force to destroy all old data;
+                        } finally {
+                            db.endTransaction();
+                        }
+                    }
+
                     return;
             }
 
@@ -384,6 +403,7 @@ public class ImProvider extends ContentProvider {
             buf.append("_id INTEGER PRIMARY KEY,");
             buf.append("username TEXT,");
             buf.append("nickname TEXT,");
+
             buf.append("provider INTEGER,");
             buf.append("account INTEGER,");
             buf.append("contactList INTEGER,");
@@ -451,6 +471,51 @@ public class ImProvider extends ContentProvider {
             db.execSQL(buf.toString());
         }
 
+        private void createMessageChatTables(SQLiteDatabase db, String tablePrefix) {
+            String tableName;
+
+            tableName = (tablePrefix != null) ? tablePrefix+TABLE_MESSAGES : TABLE_MESSAGES;
+
+            // message table e
+            db.execSQL("CREATE TABLE IF NOT EXISTS " + tableName + " (" +
+                    "_id INTEGER PRIMARY KEY," +
+                    "packet_id TEXT UNIQUE," +
+                    "contact TEXT," +
+                    "provider INTEGER," +
+                    "account INTEGER," +
+                    "body TEXT," +
+                    "date INTEGER," +    // in seconds
+                    "type INTEGER," +
+                    "err_code INTEGER NOT NULL DEFAULT 0," +
+                    "err_msg TEXT" +
+                    ");");
+
+            tableName = (tablePrefix != null) ? tablePrefix+TABLE_CHATS : TABLE_CHATS;
+
+            // chat sessions, including single person chats and group chats
+            db.execSQL("CREATE TABLE IF NOT EXISTS " + tableName + " ("+
+                    "_id INTEGER PRIMARY KEY," +
+                    "contact_id INTEGER UNIQUE," +
+                    "jid_resource TEXT," +  // the JID resource for the user, only for non-group chats
+                    "groupchat INTEGER," +   // 1 if group chat, 0 if not TODO: remove this column
+                    "last_unread_message TEXT," +  // the last unread message
+                    "last_message_date INTEGER," +  // in seconds
+                    "unsent_composed_message TEXT," + // a composed, but not sent message
+                    "shortcut INTEGER" + // which of 10 slots (if any) this chat occupies
+                    ");");
+
+            if (MAKE_MESSAGE_PRESENCE_CHAT_PERSISTENT) {
+                String contactsTableName = TABLE_CONTACTS;
+
+                db.execSQL("CREATE TRIGGER IF NOT EXISTS contact_cleanup " +
+                        "DELETE ON " + contactsTableName +
+                           " BEGIN " +
+                               "DELETE FROM chats WHERE contact_id = OLD._id;" +
+                           "END");
+            }
+
+        }
+
         @Override
         public void onOpen(SQLiteDatabase db) {
             if (db.isReadOnly()) {
@@ -466,20 +531,9 @@ public class ImProvider extends ContentProvider {
             db.execSQL("ATTACH DATABASE ':memory:' AS " + mTransientDbName + ";");
             cpDbName = mTransientDbName + ".";
 
-            // message table (since the UI currently doesn't require saving message history
-            // across IM sessions, store the message table in memory db only)
-            db.execSQL("CREATE TABLE IF NOT EXISTS " + cpDbName + TABLE_MESSAGES + " (" +
-                    "_id INTEGER PRIMARY KEY," +
-                    "packet_id TEXT UNIQUE," +
-                    "contact TEXT," +
-                    "provider INTEGER," +
-                    "account INTEGER," +
-                    "body TEXT," +
-                    "date INTEGER," +    // in seconds
-                    "type INTEGER," +
-                    "err_code INTEGER NOT NULL DEFAULT 0," +
-                    "err_msg TEXT" +
-                    ");");
+            if (!MAKE_MESSAGE_PRESENCE_CHAT_PERSISTENT) {
+                createMessageChatTables(db, cpDbName);
+            }
 
             // presence
             db.execSQL("CREATE TABLE IF NOT EXISTS " + cpDbName + TABLE_PRESENCE + " ("+
@@ -525,18 +579,6 @@ public class ImProvider extends ContentProvider {
                     "err_msg TEXT" +
                     ");");
 
-            // chat sessions, including single person chats and group chats
-            db.execSQL("CREATE TABLE IF NOT EXISTS " + cpDbName + TABLE_CHATS + " ("+
-                    "_id INTEGER PRIMARY KEY," +
-                    "contact_id INTEGER UNIQUE," +
-                    "jid_resource TEXT," +  // the JID resource for the user, only for non-group chats
-                    "groupchat INTEGER," +   // 1 if group chat, 0 if not TODO: remove this column
-                    "last_unread_message TEXT," +  // the last unread message
-                    "last_message_date INTEGER," +  // in seconds
-                    "unsent_composed_message TEXT," + // a composed, but not sent message
-                    "shortcut INTEGER" + // which of 10 slots (if any) this chat occupies
-                    ");");
-
             db.execSQL("CREATE TABLE IF NOT EXISTS " + cpDbName + TABLE_ACCOUNT_STATUS + " (" +
                     "_id INTEGER PRIMARY KEY," +
                     "account INTEGER UNIQUE," +
@@ -546,27 +588,22 @@ public class ImProvider extends ContentProvider {
             );
 
             /* when we moved the contact table out of transient_db and into the main db, the
-               contact_cleanup and group_cleanup triggers don't work anymore. It seems we can't
+               presence and groupchat cleanup triggers don't work anymore. It seems we can't
                create triggers that reference objects in a different database!
 
-            String contactsTableName = TABLE_CONTACTS;
-
-            if (USE_CONTACT_PRESENCE_TRIGGER) {
-                // Insert a default presence for newly inserted contact
-                db.execSQL("CREATE TRIGGER IF NOT EXISTS " + cpDbName + "contact_create_presence " +
-                        "INSERT ON " + cpDbName + contactsTableName +
-                            " FOR EACH ROW WHEN NEW.type != " + Im.Contacts.TYPE_GROUP +
-                                " OR NEW.type != " + Im.Contacts.TYPE_BLOCKED +
-                            " BEGIN " +
-                                "INSERT INTO presence (contact_id) VALUES (NEW._id);" +
-                            " END");
-            }
-
-            db.execSQL("CREATE TRIGGER IF NOT EXISTS " + cpDbName + "contact_cleanup " +
-                    "DELETE ON " + cpDbName + contactsTableName +
+            // Insert a default presence for newly inserted contact
+            db.execSQL("CREATE TRIGGER IF NOT EXISTS contact_create_presence " +
+                    "AFTER INSERT ON " + contactsTableName +
+                        " WHEN NEW.type != " + Im.Contacts.TYPE_GROUP +
+                        " BEGIN " +
+                            "INSERT INTO presence (contact_id) VALUES (NEW._id);" +
+                        " END");
+
+            // Remove the presence when the contact is removed.
+            db.execSQL("CREATE TRIGGER IF NOT EXISTS contact_presence_cleanup " +
+                    "DELETE ON " + contactsTableName +
                        " BEGIN " +
                            "DELETE FROM presence WHERE contact_id = OLD._id;" +
-                           "DELETE FROM chats WHERE contact_id = OLD._id;" +
                        "END");
 
             // Cleans up group members and group messages when a group chat is deleted
@@ -1162,8 +1199,7 @@ public class ImProvider extends ContentProvider {
             StringBuilder whereClause, Uri url) {
         qb.setTables(CONTACT_JOIN_PRESENCE_CHAT_AVATAR_TABLE);
         qb.setProjectionMap(sContactsProjectionMap);
-        // we don't really need the provider id in query. account id
-        // is enough.
+        // we don't really need the provider id in query. account id is enough.
         appendWhere(whereClause, Im.Contacts.ACCOUNT, "=", url.getLastPathSegment());
     }
 
@@ -1358,7 +1394,7 @@ public class ImProvider extends ContentProvider {
                     contactValues.put(Im.Contacts.REJECTED, rejected);
                 }
 
-                long rowId = 0;
+                long rowId;
 
                 /* save this code for when we add constraint (account, username) to the contacts
                    table
@@ -1385,12 +1421,11 @@ public class ImProvider extends ContentProvider {
                 rowId = db.insert(TABLE_CONTACTS, USERNAME, contactValues);
                 if (rowId > 0) {
                     sum++;
-                    if (!USE_CONTACT_PRESENCE_TRIGGER) {
-                        // seed the presence for the new contact
-                        //if (DBG) log("seedPresence for pid " + rowId);
-                        presenceValues.put(Im.Presence.CONTACT_ID, rowId);
-                        db.insert(TABLE_PRESENCE, null, presenceValues);
-                    }
+
+                    // seed the presence for the new contact
+                    if (DBG) log("### seedPresence for contact id " + rowId);
+                    presenceValues.put(Im.Presence.CONTACT_ID, rowId);
+                    db.insert(TABLE_PRESENCE, null, presenceValues);
                 }
                 
                 // yield the lock if anyone else is trying to
@@ -1526,10 +1561,22 @@ public class ImProvider extends ContentProvider {
     private String[] mQueryContactPresenceSelectionArgs = new String[1];
 
     /**
-     * This method first performs a query for all the contacts (for the given account) that
-     * don't have a presence entry in the presence table. Then for each of those contacts,
-     * the method creates a presence row. The whole thing is done inside one database transaction
-     * to increase performance.
+     * make sure the presence for all contacts of a given account is set to offline, and
+     * each contact has a presence row associated with it. However, this method does not remove
+     * presences for which the corresponding contacts no longer exist. That's probably ok since
+     * presence is kept in memory, so it won't stay around for too long. Here is the algorithm.
+     *
+     * 1. for all presence that have a corresponding contact, make it OFFLINE. This is one sqlite
+     *    call.
+     * 2. query for all the contacts that don't have a presence, and add a presence row for them.
+     *
+     * TODO simplify the presence management! The desire is to have a presence row for each
+     * TODO contact in the database, so later we can just call update() on the presence rows
+     * TODO instead of checking for the existence of presence first. The assumption is we get
+     * TODO presence updates much more frequently. However, the logic to maintain that goal is
+     * TODO overly complicated. One possible solution is to use insert_or_replace the presence rows
+     * TODO when updating the presence. That way we don't always need to maintain an empty presence
+     * TODO row for each contact.
      *
      * @param account the account of the contacts for which we want to create seed presence rows.
      */
@@ -1550,7 +1597,7 @@ public class ImProvider extends ContentProvider {
             presenceValues.put(Im.Presence.PRESENCE_STATUS, Im.Presence.OFFLINE);
             presenceValues.put(Im.Presence.PRESENCE_CUSTOM_STATUS, "");
 
-            // First: update all the presence for the account so they are offline
+            // update all the presence for the account so they are offline
             StringBuilder buf = new StringBuilder();
             buf.append(Im.Presence.CONTACT_ID);
             buf.append(" in (select ");
@@ -1568,7 +1615,10 @@ public class ImProvider extends ContentProvider {
                     mQueryContactPresenceSelectionArgs);
             if (DBG) log("seedInitialPresence: reset " + count + " presence rows to OFFLINE");
 
-            // second: add a presence row for each contact that doesn't have a presence
+            // for in-memory presence table, add a presence row for each contact that
+            // doesn't have a presence. in-memory presence table isn't reliable, and goes away
+            // when device reboot or IMProvider process dies, so we can't rely on each contact
+            // have a corresponding presence.
             if (DBG) {
                 log("seedInitialPresence: contacts_with_no_presence_selection => " +
                         CONTACTS_WITH_NO_PRESENCE_SELECTION);
@@ -1600,11 +1650,13 @@ public class ImProvider extends ContentProvider {
                 }
             }
 
-            db.setTransactionSuccessful();
-
             if (DBG) log("seedInitialPresence: added " + count + " new presence rows");
+
+            db.setTransactionSuccessful();
         } finally {
-            c.close();
+            if (c != null) {
+                c.close();
+            }
             db.endTransaction();
         }
     }