exception Malformed_key of string
exception Key_not_found of string
exception Type_error of string * string * string (* expected type, value, msg *)
-exception Parse_error of string * int (* file, lineno *)
+exception Parse_error of string * int * int * string (* file, line, col, msg *)
exception Invalid_value of (string * string) * string (* key, value, descr *)
-exception Unescape_failure
-
type validator_id = int
let get_next_validator_id =
Hashtbl.clear registry;
Hashtbl.iter (fun key value -> Hashtbl.replace registry key value) backup
-let valid_key_rex_raw = "\\w+(\\.\\w+)*"
-let config_line_raw = sprintf "\\s*(%s)\\s*=\\s*\"(.*)\"\\s*" valid_key_rex_raw
-let comment_rex = Pcre.regexp "^\\s*(#|$)"
+ (* as \\w but:
+ * - no sequences of '_' longer than 1 are permitted
+ * - no uppercase letter are permitted
+ *)
+let valid_step_rex_raw = "[a-z0-9]+(_[a-z0-9]+)*"
+let valid_key_rex_raw =
+ sprintf "%s(\\.%s)*" valid_step_rex_raw valid_step_rex_raw
let valid_key_rex = Pcre.regexp ("^" ^ valid_key_rex_raw ^ "$")
-let config_line_rex = Pcre.regexp ("^" ^ config_line_raw ^ "$")
-
-let is_comment s = Pcre.pmatch ~rex:comment_rex s
-let escape = String.escaped
-let unescape =
- let lexer = lazy (Genlex.make_lexer []) in
- fun s ->
- let tok_stream = Lazy.force lexer (Stream.of_string ("\"" ^ s ^ "\"")) in
- match Stream.peek tok_stream with
- | Some (Genlex.String s) -> s
- | _ -> raise Unescape_failure
+ (* escapes for xml configuration file *)
+let (escape, unescape) =
+ let (in_enc, out_enc) = (`Enc_utf8, `Enc_utf8) in
+ (Netencoding.Html.encode ~in_enc ~out_enc (),
+ Netencoding.Html.decode ~in_enc ~out_enc ~entity_base:`Xml ())
let key_is_valid key =
if not (Pcre.pmatch ~rex:valid_key_rex key) then
value_is_valid ~key ~value;
Hashtbl.replace registry key value
+let env_var_of_key =
+ let dot_RE = Pcre.regexp "\\." in
+ fun key ->
+ Pcre.replace ~rex:dot_RE ~templ:"__" (String.uppercase key)
+
let get key =
key_is_valid key;
- try
- Hashtbl.find registry key
- with Not_found -> raise (Key_not_found key)
+ let registry_value =
+ try
+ Some (Hashtbl.find registry key)
+ with Not_found -> None
+ in
+ let env_value =
+ try
+ Some (Sys.getenv (env_var_of_key key))
+ with Not_found -> None
+ in
+ match (registry_value, env_value) with
+ | Some reg, Some env -> env
+ | Some reg, None -> reg
+ | None, Some env -> env
+ | None, None -> raise (Key_not_found key)
let set = set' registry
let setter ~key ~value = set ~key ~value:(to_string value) in
(getter, setter)
+let (get_string, set_string) = (get, set)
let (get_int, set_int) = mk_get_set "int" int_of_string string_of_int
let (get_float, set_float) = mk_get_set "float" float_of_string string_of_float
let (get_string_list, set_string_list) =
let save_to fname =
let oc = open_out fname in
+ output_string oc "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n";
+ output_string oc "<helm_registry>\n";
try
Hashtbl.iter
(fun key value ->
- output_string oc (sprintf "%s = \"%s\"" key (escape value)))
+ fprintf oc " <value key=\"%s\">%s</value>\n" key (escape value))
registry;
+ output_string oc "</helm_registry>";
close_out oc
with e ->
close_out oc;
raise e
-let load_from fname =
- let backup = backup_registry () in
- Hashtbl.clear registry;
- let ic = open_in fname in
- let lineno = ref 0 in
- try
- while true do
- incr lineno;
- let line = input_line ic in
- if not (is_comment line) then
- let subs = Pcre.extract ~rex:config_line_rex line in
- let (key, value) = (subs.(1), unescape subs.(3)) in
- set ~key ~value
- done
- with
- | End_of_file -> close_in ic
- | Malformed_key _ | Unescape_failure | Not_found ->
- restore_registry backup;
- raise (Parse_error (fname, !lineno))
- | e ->
- close_in ic;
- restore_registry backup;
- raise e
-
let add_validator ~key ~validator ~descr =
let id = get_next_validator_id () in
Hashtbl.add validators key (validator, descr);
id
-(*
- (* DEBUGGING *)
+open Pxp_document
+open Pxp_types
+open Pxp_yacc
+
+let load_from =
+ let config = default_config in
+ let entry = `Entry_document [ `Extend_dtd_fully; `Parse_xml_decl ] in
+ fun fname ->
+ let document =
+ parse_wfdocument_entity config (from_file fname) default_spec
+ in
+ let fill_registry () =
+ document#root#iter_nodes (fun n ->
+ try
+ (match n#node_type with
+ | T_element "value" ->
+ let key = n#required_string_attribute "key" in
+ let value = n#data in
+ set ~key ~value
+ | _ -> ())
+ with exn ->
+ let (fname, line, pos) = n#position in
+ raise (Parse_error (fname, line, pos,
+ "Uncaught exception: " ^ Printexc.to_string exn)))
+ in
+ let backup = backup_registry () in
+ Hashtbl.clear registry;
+ try
+ fill_registry ()
+ with exn ->
+ restore_registry backup;
+ raise exn
+
+ (* DEBUGGING ONLY *)
+
let dump () = Hashtbl.iter (fun k v -> printf "%s = %s\n" k v) registry
-*)
(** Configuration repository for HELM applications.
*
- * key ::= path
- * path ::= component ( '.' component )*
- * component ::= ( alpha | num | '_' )+
+ * ++ Keys format ++
*
- * Suggested usage <application>.<setting>:
- * e.g. gTopLevel.prooffile, http_getter.port, ...
+ * key ::= path
+ * path ::= component ( '.' component )*
+ * component ::= ( lowercase_alpha | num | '_' )+
+ * # with the only exception that sequences of '_' longer than 1 aren't valid
+ * # components
*
- * Configuration file example:
+ * Suggested usage <application>.<setting>:
+ * e.g. gTopLevel.prooffile, http_getter.port, ...
+ *
+ * ++ Configuration file example ++
*
* gTopLevel.prooffile = "/home/zack/prooffile"
* http_getter.port = "58080"
+ *
+ * ++ Environment variable override ++
+ *
+ * each key has an associated environment variable name. At runtime (i.e. when
+ * "get" requests are performed) a variable with this name will be looked for,
+ * if it's defined it will override the value present (or absent) in the
+ * registry.
+ * Environment variables are _not_ considered when saving the configuration to
+ * a configuration file (via "save_to" function below) .
+ *
+ * Mapping between keys and environment variables is as follows:
+ * - the whole key is uppercased
+ * - each "." is converted to "__"
+ * E.g.: my.foo_ish.application -> MY__FOO_ISH__APPLICATION
*)
(** raised when a looked up key can't be found
(** raised when an error is encountered while parsing a configuration file
* @param fname file name
- * @param lno line number *)
-exception Parse_error of string * int
+ * @param line line number
+ * @param col column number
+ * @param msg error description
+ *)
+exception Parse_error of string * int * int * string
(** raised when a given <key,value> pair fails validity test(s)
* @param pair <key,value> pair
* Using the functions below this module could be used as a repository of
* key/value pairs *)
+ (** lookup key in registry with environment variable override *)
val get: string -> string
val set: key:string -> value:string -> unit
* parsing of an integer number from ; strings list to the splitting at blanks
* of it (heading and trailing blanks are removed before splitting) *)
+val get_string: string -> string (* alias for bare "get" above *)
val get_int: string -> int
val get_float: string -> float
val get_string_list: string -> string list
+ (* alias for bare "set" above *)
+val set_string: key:string -> value:string -> unit
val set_int: key:string -> value:int -> unit
val set_float: key:string -> value:float -> unit
val set_string_list: key:string -> value:string list -> unit
projects / helm.git / commitdiff