[Libguestfs] [PATCH 1/5] builder: extract Yajl helper functions to yajl.ml

Extract the yajl object_get_* helpers in the Yajl module since this could be useful for any Yajl user code. --- builder/simplestreams_parser.ml | 52 -------------------------------------- builder/yajl.ml | 55 +++++++++++++++++++++++++++++++++++++++++ builder/yajl.mli | 29 ++++++++++++++++++++++ 3 files changed, 84 insertions(+), 52 deletions(-) diff --git a/builder/simplestreams_parser.ml b/builder/simplestreams_parser.ml index 81e70189a..8844d476b 100644 --- a/builder/simplestreams_parser.ml +++ b/builder/simplestreams_parser.ml @@ -28,58 +28,6 @@ let ensure_trailing_slash str = if String.length str > 0 && str.[String.length str - 1] <> '/' then str ^ "/" else str -let object_find_optional key = function - | Yajl_object o -> - (match List.filter (fun (k, _) -> k = key) (Array.to_list o) with - | [(k, v)] -> Some v - | [] -> None - | _ -> error (f_"more than value for the key '%s'") key) - | _ -> error (f_"the value of the key '%s' is not an object") key - -let object_find key yv = - match object_find_optional key yv with - | None -> error (f_"missing value for the key '%s'") key - | Some v -> v - -let object_get_string key yv = - match object_find key yv with - | Yajl_string s -> s - | _ -> error (f_"the value for the key '%s' is not a string") key - -let object_find_object key yv = - match object_find key yv with - | Yajl_object _ as o -> o - | _ -> error (f_"the value for the key '%s' is not an object") key - -let object_find_objects fn = function - | Yajl_object o -> filter_map fn (Array.to_list o) - | _ -> error (f_"the value is not an object") - -let object_get_object key yv = - match object_find_object key yv with - | Yajl_object o -> o - | _ -> assert false (* object_find_object already errors out. *) - -let object_get_number key yv = - match object_find key yv with - | Yajl_number n -> n - | Yajl_double d -> Int64.of_float d - | _ -> error (f_"the value for the key '%s' is not an integer") key - -let objects_get_string key yvs = - let rec loop = function - | [] -> None - | x :: xs -> - (match object_find_optional key x with - | Some (Yajl_string s) -> Some s - | Some _ -> error (f_"the value for key '%s' is not a string as expected") key - | None -> loop xs - ) - in - match loop yvs with - | Some s -> s - | None -> error (f_"the key '%s' was not found in a list of objects") key - let get_index ~downloader ~sigchecker { Sources.uri = uri; proxy = proxy } = diff --git a/builder/yajl.ml b/builder/yajl.ml index 00e4dac4b..e53706abc 100644 --- a/builder/yajl.ml +++ b/builder/yajl.ml @@ -16,6 +16,9 @@ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *) +open Common_gettext.Gettext +open Common_utils + type yajl_val = | Yajl_null | Yajl_string of string @@ -26,3 +29,55 @@ type yajl_val = | Yajl_bool of bool external yajl_tree_parse : string -> yajl_val = "virt_builder_yajl_tree_parse" + +let object_find_optional key = function + | Yajl_object o -> + (match List.filter (fun (k, _) -> k = key) (Array.to_list o) with + | [(k, v)] -> Some v + | [] -> None + | _ -> error (f_"more than value for the key '%s'") key) + | _ -> error (f_"the value of the key '%s' is not an object") key + +let object_find key yv = + match object_find_optional key yv with + | None -> error (f_"missing value for the key '%s'") key + | Some v -> v + +let object_get_string key yv = + match object_find key yv with + | Yajl_string s -> s + | _ -> error (f_"the value for the key '%s' is not a string") key + +let object_find_object key yv = + match object_find key yv with + | Yajl_object _ as o -> o + | _ -> error (f_"the value for the key '%s' is not an object") key + +let object_find_objects fn = function + | Yajl_object o -> filter_map fn (Array.to_list o) + | _ -> error (f_"the value is not an object") + +let object_get_object key yv = + match object_find_object key yv with + | Yajl_object o -> o + | _ -> assert false (* object_find_object already errors out. *) + +let object_get_number key yv = + match object_find key yv with + | Yajl_number n -> n + | Yajl_double d -> Int64.of_float d + | _ -> error (f_"the value for the key '%s' is not an integer") key + +let objects_get_string key yvs = + let rec loop = function + | [] -> None + | x :: xs -> + (match object_find_optional key x with + | Some (Yajl_string s) -> Some s + | Some _ -> error (f_"the value for key '%s' is not a string as expected") key + | None -> loop xs + ) + in + match loop yvs with + | Some s -> s + | None -> error (f_"the key '%s' was not found in a list of objects") key diff --git a/builder/yajl.mli b/builder/yajl.mli index 9771e5399..ca0eb92f4 100644 --- a/builder/yajl.mli +++ b/builder/yajl.mli @@ -27,3 +27,32 @@ type yajl_val = val yajl_tree_parse : string -> yajl_val (** Parse the JSON string. *) + +val object_get_string : string -> yajl_val -> string +(** [object_get_string key yv] gets the value of the [key] field as a string + in the [yv] structure *) + +val object_find_object : string -> yajl_val -> yajl_val +(** [object_get_object key yv] gets the value of the [key] field as a yajl + value in the [yv] structure. + + Mind the returned type is different from [object_get_object] *) + +val object_get_object : string -> yajl_val -> (string * yajl_val) array +(** [object_get_object key yv] gets the value of the [key] field as a Yajl + object in the [yv] structure *) + +val object_get_number : string -> yajl_val -> int64 +(** [object_get_number key yv] gets the value of the [key] field as an + integer in the [yv] structure *) + +val objects_get_string : string -> yajl_val list -> string +(** [objects_get_string key yvs] gets the value of the [key] field as a string + in an [yvs] list of yajl_val structure. + + The key may not be found at all in the list, in which case an error + is raised *) + +val object_find_objects : ((string * yajl_val) -> 'a option) -> yajl_val -> 'a list +(** [object_find_objects fn obj] returns all the Yajl objects matching the [fn] + function in [obj] list. *) -- 2.11.0