TrackerMinerFS

TrackerMinerFS — Abstract base class for filesystem miners

Functions

Types and Values

Includes

#include <libtracker-miner/tracker-miner.h>

Description

TrackerMinerFS is an abstract base class for miners that collect data from a filesystem where parent/child relationships need to be inserted into the database correctly with queue management.

All the filesystem crawling and monitoring is abstracted away, leaving to implementations the decisions of what directories/files should it process, and the actual data extraction.

Example creating a TrackerMinerFS with our own file system root and data provider.

First create our class and base it on TrackerMinerFS:

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G_DEFINE_TYPE_WITH_CODE (MyMinerFiles, my_miner_files, TRACKER_TYPE_MINER_FS,
                         G_IMPLEMENT_INTERFACE (G_TYPE_INITABLE,
                                                my_miner_files_initable_iface_init))

Later in our class creation function, we are supplying the arguments we want. In this case, the 'root' is a GFile pointing to a root URI location (for example 'file:///') and 'data_provider' is a TrackerDataProvider used to enumerate 'root' and return children it finds. If 'data_provider' is NULL (the default), then a TrackerFileDataProvider is created automatically.

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// Note that only 'name' is mandatory
miner = g_initable_new (MY_TYPE_MINER_FILES,
                        NULL,
                        error,
                        "name", "MyMinerFiles",
                        "root", root,
                        "data-provider", data_provider,
                        "processing-pool-wait-limit", 10,
                        "processing-pool-ready-limit", 100,
                        NULL);

Functions

tracker_miner_fs_error_quark ()

GQuark
tracker_miner_fs_error_quark (void);

Gives the caller the GQuark used to identify TrackerMinerFS errors in GError structures. The GQuark is used as the domain for the error.

Returns

the GQuark used for the domain of a GError.

Since: 1.2


tracker_miner_fs_get_indexing_tree ()

TrackerIndexingTree *
tracker_miner_fs_get_indexing_tree (TrackerMinerFS *fs);

Returns the TrackerIndexingTree which determines what files/directories are indexed by fs

Parameters

fs

a TrackerMinerFS

 

Returns

The TrackerIndexingTree holding the indexing configuration.

[transfer none]


tracker_miner_fs_get_data_provider ()

TrackerDataProvider *
tracker_miner_fs_get_data_provider (TrackerMinerFS *fs);

Returns the TrackerDataProvider implementation, which is being used to supply GFile and GFileInfo content to Tracker.

Parameters

fs

a TrackerMinerFS

 

Returns

The TrackerDataProvider supplying content.

[transfer none]

Since: 1.2


tracker_miner_fs_get_throttle ()

gdouble
tracker_miner_fs_get_throttle (TrackerMinerFS *fs);

Gets the current throttle value, see tracker_miner_fs_set_throttle() for more details.

Parameters

fs

a TrackerMinerFS

 

Returns

a double representing a value between 0.0 and 1.0.

Since: 0.8


tracker_miner_fs_set_throttle ()

void
tracker_miner_fs_set_throttle (TrackerMinerFS *fs,
                               gdouble throttle);

Tells the filesystem miner to throttle its operations. A value of 0.0 means no throttling at all, so the miner will perform operations at full speed, 1.0 is the slowest value. With a value of 1.0, the fs is typically waiting one full second before handling the next batch of queued items to be processed.

Parameters

fs

a TrackerMinerFS

 

throttle

a double between 0.0 and 1.0

 

Since: 0.8


tracker_miner_fs_check_file ()

void
tracker_miner_fs_check_file (TrackerMinerFS *fs,
                             GFile *file,
                             gint priority,
                             gboolean check_parents);

Tells the filesystem miner to check and index a file at a given priority, this file must be part of the usual crawling directories of TrackerMinerFS. See tracker_indexing_tree_add().

Parameters

fs

a TrackerMinerFS

 

file

GFile for the file to check

 

priority

the priority of the check task

 

check_parents

whether to check parents and eligibility or not

 

Since: 0.10


tracker_miner_fs_notify_finish ()

void
tracker_miner_fs_notify_finish (TrackerMinerFS *fs,
                                GTask *task,
                                const gchar *sparql,
                                GError *error);

Notifies fs that all processing on file has been finished, if any error happened during file data processing, it should be passed in error , else sparql should contain correct SPARQL representing the operation in particular.

This function is expected to be called in reaction to all TrackerMinerFS signals

Parameters

fs

a TrackerMinerFS

 

task

a GTask obtained in a TrackerMinerFS signal/vmethod

 

sparql

Resulting sparql for the given operation, or NULL if there is an error.

[nullable]

error

a GError with the error that happened during processing, or NULL.

 

tracker_miner_fs_get_urn ()

const gchar *
tracker_miner_fs_get_urn (TrackerMinerFS *fs,
                          GFile *file);

If the item exists in the store, this function retrieves the URN for a GFile being currently processed.

If file is not being currently processed by fs , or doesn't exist in the store yet, NULL will be returned.

Parameters

fs

a TrackerMinerFS

 

file

a GFile obtained in “process-file”

 

Returns

The URN containing the data associated to file , or NULL.

[transfer none][nullable]

Since: 0.8


tracker_miner_fs_query_urn ()

gchar *
tracker_miner_fs_query_urn (TrackerMinerFS *fs,
                            GFile *file);

If the item exists in the store, this function retrieves the URN of the given GFile

If file doesn't exist in the store yet, NULL will be returned.

Parameters

fs

a TrackerMinerFS

 

file

a GFile

 

Returns

A newly allocated string with the URN containing the data associated to file , or NULL.

[transfer full]

Since: 0.10


tracker_miner_fs_has_items_to_process ()

gboolean
tracker_miner_fs_has_items_to_process (TrackerMinerFS *fs);

The fs keeps many priority queus for content it is processing. This function returns TRUE if the sum of all (or any) priority queues is more than 0. This includes items deleted, created, updated, moved or being written back.

Parameters

fs

a TrackerMinerFS

 

Returns

TRUE if there are items to process in the internal queues, otherwise FALSE.

Since: 0.10

Types and Values

enum TrackerMinerFSEventType

Members

TRACKER_MINER_FS_EVENT_CREATED

   

TRACKER_MINER_FS_EVENT_UPDATED

   

TRACKER_MINER_FS_EVENT_DELETED

   

TRACKER_MINER_FS_EVENT_MOVED

   

struct TrackerMinerFS

struct TrackerMinerFS {
	TrackerMiner parent;
	TrackerMinerFSPrivate *priv;
};

Abstract miner implementation to get data from the filesystem.


TrackerMinerFSClass

typedef struct {
	TrackerMinerClass parent;

	gboolean (* process_file)             (TrackerMinerFS       *fs,
	                                       GFile                *file,
					       GTask                *task);
	void     (* finished)                 (TrackerMinerFS       *fs,
	                                       gdouble               elapsed,
	                                       gint                  directories_found,
	                                       gint                  directories_ignored,
	                                       gint                  files_found,
	                                       gint                  files_ignored);
	gboolean (* process_file_attributes)  (TrackerMinerFS       *fs,
	                                       GFile                *file,
					       GTask                *task);
	void     (* finished_root)            (TrackerMinerFS       *fs,
	                                       GFile                *root,
	                                       gint                  directories_found,
	                                       gint                  directories_ignored,
	                                       gint                  files_found,
	                                       gint                  files_ignored);
	gchar *  (* remove_file)              (TrackerMinerFS       *fs,
	                                       GFile                *file);
	gchar *  (* remove_children)          (TrackerMinerFS       *fs,
	                                       GFile                *file);
	gchar *  (* move_file)                (TrackerMinerFS       *fs,
					       GFile                *dest,
	                                       GFile                *source,
	                                       gboolean              recursive);

	gboolean (* filter_event)             (TrackerMinerFS          *fs,
	                                       TrackerMinerFSEventType  type,
	                                       GFile                   *file,
	                                       GFile                   *source_file);

	/* <Private> */
	gpointer padding[20];
} TrackerMinerFSClass;

Prototype for the abstract class, process_file must be implemented in the deriving class in order to actually extract data.

Members

TrackerMinerClass parent;

parent object class

 

process_file ()

Called when the metadata associated to a file is requested.

 

finished ()

Called when all processing has been performed.

 

process_file_attributes ()

Called when the metadata associated with a file's attributes changes, for example, the mtime.

 

finished_root ()

Called when all resources on a particular root URI have been processed.

 

remove_file ()

Called when a file is removed.

 

remove_children ()

Called when children have been removed.

 

move_file ()

Called when a file has moved.

 

filter_event ()

Called to filter the event happening to a file.

 

gpointer padding[20];

Reserved for future API improvements.

 

enum TrackerMinerFSError

Possible errors returned when calling creating new objects based on the TrackerMinerFS type and other APIs available with this class.

Members

TRACKER_MINER_FS_ERROR_INIT

There was an error during initialization of the object. The specific details are in the message.

 

Since: 1.2