Re: [PATCH 1/6] Add a serializing function for medias

[Víctor M. Jáquez L. <vjaquez igalia com>]

Hi,

comments on line

On Fri, May 28, 2010 at 10:50:49AM +0200, Juan A. Suarez Romero wrote:
> It returns a string that represent a media.
> 
> Lot of times, having a "serialized" version of a media is very useful. For
> instance, one can save this serial in a list, or send it to a non-grilo
> compliant application.
> 
> Then, the media can be recovered from the serial.
> 
> Serial follows the same scheme as an URI:
> 
>   <type>://<escaped_source_name>/<escaped_id>
> 
> As it can be seen, both "id" and "source" are required in media in order to
> build the serial.
> 
> <type> denotes the type of media we are dealing with. Thus, we will have:
> 
>    GrlMedia      => "grl"
>    GrlMediaAudio => "grlaudio"
>    GrlMediaVideo => "grlvideo"
>    GrlMediaBox   => "grlbox"
>    GrlMediaImage => "grlimage"
> 
> It is worth to tell that the implementation takes in account future new medias.
> Thus, if in future a GrlMediaFoo type is added, then <type> will be "grlfoo"
> for this new media, without needing changes in code.
> ---
>  src/data/grl-media.c |   35 +++++++++++++++++++++++++++++++++++
>  src/data/grl-media.h |    3 +++
>  2 files changed, 38 insertions(+), 0 deletions(-)
> 
> diff --git a/src/data/grl-media.c b/src/data/grl-media.c
> index 50310d1..4a85103 100644
> --- a/src/data/grl-media.c
> +++ b/src/data/grl-media.c
> @@ -103,3 +103,38 @@ grl_media_set_rating (GrlMedia *media, gfloat rating, gfloat max)
>  		      GRL_METADATA_KEY_RATING,
>  		      normalized_value);
>  }
> +
> +gchar *
> +grl_media_serialize (GrlMedia *media)
> +{
> +  GRegex *type_regex;
> +  const gchar *id;
> +  const gchar *source;
> +  const gchar *type_name;
> +  gchar *escaped_id;
> +  gchar *escaped_source;
> +  gchar *protocol;
> +  gchar *serial;
> +
> +  g_return_val_if_fail (GRL_IS_MEDIA (media), NULL);
> +  g_return_val_if_fail ((id = grl_media_get_id (media)), NULL);
> +  g_return_val_if_fail ((source = grl_media_get_source (media)), NULL);
> +
> +  type_name = g_type_name (G_TYPE_FROM_INSTANCE (media));
> +
> +  /* Convert typename to scheme protocol */
> +  type_regex = g_regex_new ("GrlMedia(.*)", 0, 0, NULL);
> +  protocol = g_regex_replace (type_regex, type_name, -1, 0, "grl\\L\\1\\E", 0, NULL);
> +  g_regex_unref (type_regex);

Is it necessary to use the regex machinery here?

> +
> +  /* Build serial string with escaped components */
> +  escaped_id = g_uri_escape_string (id, NULL, TRUE);
> +  escaped_source = g_uri_escape_string (source, NULL, TRUE);
> +
> +  serial = g_strconcat (protocol, "://", escaped_source, "/", escaped_id, NULL);
> +
> +  g_free (escaped_id);
> +  g_free (escaped_source);
> +
> +  return serial;
> +}
> diff --git a/src/data/grl-media.h b/src/data/grl-media.h
> index 627ec35..adcaccd 100644
> --- a/src/data/grl-media.h
> +++ b/src/data/grl-media.h
> @@ -384,8 +384,11 @@ void grl_media_set_rating (GrlMedia *media, gfloat rating, gfloat max);
>    grl_data_get_string(GRL_DATA((data)), GRL_METADATA_KEY_LAST_PLAYED)
>  
>  GType grl_media_get_type (void) G_GNUC_CONST;
> +
>  GrlMedia *grl_media_new (void);
>  
> +gchar *grl_media_serialize (GrlMedia *media);
> +
>  G_END_DECLS
>  
>  #endif /* _GRL_MEDIA_H_ */