pidgin/pidgin

GSoC History API including sqlite history adapter

2021-10-12, James Culver
741992355ead
GSoC History API including sqlite history adapter

The History API has been created to drive all message handling in purple3. It will be used to update existing messages for edits, reactions, pinning, read/deliver receipts, etc. The API uses an adapter pattern, to abstract out backends, but provides a SQLite3 backend by default.

It also provides search capabilities using a custom query language that can easily be expanded over time. It will be use by both the end user to search messages and the frontends to implement features like a pinned messages button. A command line utility is also provided for searching outside of the program itself.

## Remaining Items

**These all will most likely be done by the Pidgin core team after GSoC when we figure out exactly how to solve them.**

Need to store database in purple config directory
* Gary has spent some time looking at this and it looks like the purple-history cli will need to become a purple-ui to make this work write as in the future other adapters will be plugins.

Other things to consider:
- For simplicity, the SqliteHistoryAdapter is parsing the query itself, but for consistency having `PurpleHistoryAdapter` parse the query and pass tokens to the subclass might be something we want to do.

Testing Done:
## Unit Tests
History Manager
History Adapter

## Integration Tests
purplehistorycore created for integration tests.
PurpleSqliteHistoryAdapter functionality tested:
- Creates proper db schema
- Writes logs
- Reads logs
- Queries using query language
- Deletes using query language

Bugs closed: PIDGIN-17526, PIDGIN-17532, PIDGIN-17533, PIDGIN-17534

Reviewed at https://reviews.imfreedom.org/r/877/
/* purple
*
* Purple is the legal property of its developers, whose names are too numerous
* to list here. Please refer to the COPYRIGHT file distributed with this
* source distribution.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1301 USA
*/
#if !defined(PURPLE_GLOBAL_HEADER_INSIDE) && !defined(PURPLE_COMPILATION)
# error "only <purple.h> may be included directly"
#endif
#ifndef PURPLE_IMAGE_STORE_H
#define PURPLE_IMAGE_STORE_H
/**
* SECTION:image-store
* @include:image-store.h
* @section_id: libpurple-image-store
* @short_description: a global, temporary storage for images
* @title: Image store
*
* Image store references #PurpleImage's by a simple integer value.
* It's a convenient way to embed images in HTML-like strings.
*
* Integer ID's are tracked for being valid - when a image is destroyed, it's
* also removed from the store. If the application runs for a very long time and
* all possible id numbers from integer range are utilized, it will use
* previously released numbers.
*/
#include "image.h"
/**
* PURPLE_IMAGE_STORE_PROTOCOL:
*
* A global URI prefix for images stored in this subsystem.
*/
#define PURPLE_IMAGE_STORE_PROTOCOL "purple-image:"
/**
* PURPLE_IMAGE_STORE_STOCK_PROTOCOL:
*
* A global URI prefix for stock images, with names defined by libpurple and
* contents defined by the UI.
*/
#define PURPLE_IMAGE_STORE_STOCK_PROTOCOL "purple-stock-image:"
G_BEGIN_DECLS
/**
* purple_image_store_add:
* @image: the image.
*
* Permanently adds an image to the store. If the @image is already in the
* store, it will return its current id.
*
* This function increases @image's reference count, so it won't be destroyed
* until image store subsystem is shut down. Don't decrease @image's reference
* count by yourself - if you don't want the store to hold the reference,
* use #purple_image_store_add_weak.
*
* Returns: the unique identifier for the @image.
*/
guint
purple_image_store_add(PurpleImage *image);
/**
* purple_image_store_add_weak:
* @image: the image.
*
* Adds an image to the store without increasing reference count. It will be
* removed from the store when @image gets destroyed.
*
* If the @image is already in the store, it will return its current id.
*
* Returns: the unique identifier for the @image.
*/
guint
purple_image_store_add_weak(PurpleImage *image);
/**
* purple_image_store_add_temporary:
* @image: the image.
*
* Adds an image to the store to be used in a short period of time.
* If the @image is already in the store, it will just return its current id.
*
* Increases reference count for the @image for a time long enough to display
* the @image by the UI. In current implementation it's five seconds, but may be
* changed in the future, so if you need more sophisticated reference
* management, implement it on your own.
*
* Returns: the unique identifier for the @image.
*/
guint
purple_image_store_add_temporary(PurpleImage *image);
/**
* purple_image_store_get:
* @id: the unique identifier of an image.
*
* Finds the image with a certain identifier within a store.
*
* Returns: (transfer none): the image referenced by @id, or %NULL if it
* doesn't exists.
*/
PurpleImage *
purple_image_store_get(guint id);
/**
* purple_image_store_get_from_uri:
* @uri: the URI of a potential #PurpleImage. Should not be %NULL.
*
* Checks, if the @uri is pointing to any #PurpleImage by referring
* to #PURPLE_IMAGE_STORE_PROTOCOL and returns the image, if it's valid.
*
* The function doesn't throw any warning, if the @uri is for any
* other protocol.
*
* Returns: (transfer none): the image referenced by @uri, or %NULL if it
* doesn't point to any valid image.
*/
PurpleImage *
purple_image_store_get_from_uri(const gchar *uri);
/**
* purple_image_store_get_uri:
* @image: the image.
*
* Generates an URI for the @image, to be retrieved using
* #purple_image_store_get_from_uri.
*
* Returns: (transfer full): the URI for the @image. Should be #g_free'd when
* you done using it.
*/
gchar *
purple_image_store_get_uri(PurpleImage *image);
/**
* _purple_image_store_init: (skip)
*
* Initializes the image store subsystem.
*/
void
_purple_image_store_init(void);
/**
* _purple_image_store_uninit: (skip)
*
* Uninitializes the image store subsystem.
*/
void
_purple_image_store_uninit(void);
G_END_DECLS
#endif /* PURPLE_IMAGE_STORE_H */