package data-encoding
Library of JSON and binary encoding combinators
Install
Dune Dependency
Authors
Maintainers
Sources
data-encoding-v1.0.1.tar.gz
md5=82d6e7783274595c82cff4562e2b06a2
sha512=df5d00dfef8afeada8a6aee2a97d491a2ce20cfe90aed203848f6098ba05ba60e2ee9d1afc0c6c07cf32dad3f8e34c0b55cf900ef1f2e7a72d704f07fd32e651
doc/src/data-encoding/json_stream.ml.html
Source file json_stream.ml
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487
(*****************************************************************************) (* *) (* Open Source License *) (* Copyright (c) 2020 Nomadic Labs <contact@nomadic-labs.com> *) (* *) (* Permission is hereby granted, free of charge, to any person obtaining a *) (* copy of this software and associated documentation files (the "Software"),*) (* to deal in the Software without restriction, including without limitation *) (* the rights to use, copy, modify, merge, publish, distribute, sublicense, *) (* and/or sell copies of the Software, and to permit persons to whom the *) (* Software is furnished to do so, subject to the following conditions: *) (* *) (* The above copyright notice and this permission notice shall be included *) (* in all copies or substantial portions of the Software. *) (* *) (* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR*) (* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, *) (* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL *) (* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER*) (* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING *) (* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER *) (* DEALINGS IN THE SOFTWARE. *) (* *) (*****************************************************************************) type jsonm_lexeme = [ `Null | `Bool of bool | `String of string | `Float of float | `Name of string | `As | `Ae | `Os | `Oe ] let string_of_float f = let fract, intr = modf f in if fract = 0.0 then Format.asprintf "%.0f" intr else Format.asprintf "%g" f let string_needs_escaping_at index s = let exception At of int in try for i = index to String.length s - 1 do match s.[i] with | '\"' | '\n' | '\r' | '\b' | '\t' | '\\' | '\x00' .. '\x1F' -> raise (At i) | _ -> () done ; -1 with At i -> i let do_escape_string s = let buff = Buffer.create (String.length s) in for i = 0 to String.length s - 1 do match s.[i] with | '\"' -> Buffer.add_string buff "\\\"" | '\n' -> Buffer.add_string buff "\\n" | '\r' -> Buffer.add_string buff "\\r" | '\b' -> Buffer.add_string buff "\\b" | '\t' -> Buffer.add_string buff "\\t" | '\\' -> Buffer.add_string buff "\\\\" | '\x00' .. '\x1F' as c -> Format.kasprintf (Buffer.add_string buff) "\\u%04x" (Char.code c) | c -> Buffer.add_char buff c done ; Buffer.contents buff let escape_string s = if string_needs_escaping_at 0 s >= 0 then do_escape_string s else s (** small_string_seq_of_jsonm_lexeme_seq: converts a seq of lexeme into a naive seq of small strings. This may or may not be appripriate depending on the way the resulting seq is consumed. *) let small_string_seq_of_jsonm_lexeme_seq ~newline (s : jsonm_lexeme Seq.t) : string Seq.t = let rec sseq first depth seq () = match seq () with | Seq.Nil -> assert (depth = 0) ; if newline then Seq.Cons ("\n", Seq.empty) else Seq.Nil | Seq.Cons (`Null, seq) -> let tail = Seq.Cons ("null", sseq false depth seq) in if (not first) && depth > 0 then Seq.Cons (",", fun () -> tail) else tail | Seq.Cons (`Bool true, seq) -> let tail = Seq.Cons ("true", sseq false depth seq) in if (not first) && depth > 0 then Seq.Cons (",", fun () -> tail) else tail | Seq.Cons (`Bool false, seq) -> let tail = Seq.Cons ("false", sseq false depth seq) in if (not first) && depth > 0 then Seq.Cons (",", fun () -> tail) else tail | Seq.Cons (`As, seq) -> let tail = Seq.Cons ("[", sseq true (depth + 1) seq) in if (not first) && depth > 0 then Seq.Cons (",", fun () -> tail) else tail | Seq.Cons (`Ae, seq) -> Seq.Cons ("]", sseq false (depth - 1) seq) | Seq.Cons (`Os, seq) -> let tail = Seq.Cons ("{", sseq true (depth + 1) seq) in if (not first) && depth > 0 then Seq.Cons (",", fun () -> tail) else tail | Seq.Cons (`Oe, seq) -> Seq.Cons ("}", sseq false (depth - 1) seq) | Seq.Cons (`String s, seq) -> let tail = Seq.Cons ( "\"", fun () -> Seq.Cons ( escape_string s, fun () -> Seq.Cons ("\"", sseq false depth seq) ) ) in if (not first) && depth > 0 then Seq.Cons (",", fun () -> tail) else tail | Seq.Cons (`Float f, seq) -> let f = string_of_float f in let tail = Seq.Cons (f, sseq false depth seq) in if (not first) && depth > 0 then Seq.Cons (",", fun () -> tail) else tail | Seq.Cons (`Name n, seq) -> let tail = Seq.Cons ( "\"", fun () -> Seq.Cons ( escape_string n, fun () -> Seq.Cons ("\"", fun () -> Seq.Cons (":", sseq true depth seq)) ) ) in if (not first) && depth > 0 then Seq.Cons (",", fun () -> tail) else tail in sseq false 0 s let dump_unescaped_string chunk_size_hint buff str index seq = let rec aux bytes_left_in_buff index = if bytes_left_in_buff > String.length str - index then ( Buffer.add_substring buff str index (String.length str - index) ; seq ()) else ( Buffer.add_substring buff str index bytes_left_in_buff ; let s = Buffer.contents buff in Buffer.clear buff ; Seq.Cons (s, fun () -> aux chunk_size_hint (index + bytes_left_in_buff))) in aux (chunk_size_hint - Buffer.length buff) index (* This is written with the assumption that there aren't many characters that need escaping: a few here and there, maybe just a couple of newlines in a block of text. Breaking this assumption does not cause errors. However, the performances might degrade somewhat. *) let dump_escaped_string chunk_size_hint buff str seq = let rec aux_outer bytes_left_in_buff index = let next_escape = string_needs_escaping_at index str in if bytes_left_in_buff <= 6 then ( let s = Buffer.contents buff in Buffer.clear buff ; Seq.Cons (s, fun () -> aux_outer chunk_size_hint index)) else if next_escape < 0 then (* string does not need escaping: dump the rest of the string as is *) dump_unescaped_string chunk_size_hint buff str index seq else if next_escape = 0 then ( (* index is at character that needs escaping *) (match str.[index] with | '\"' -> Buffer.add_string buff "\\\"" | '\n' -> Buffer.add_string buff "\\n" | '\r' -> Buffer.add_string buff "\\r" | '\b' -> Buffer.add_string buff "\\b" | '\t' -> Buffer.add_string buff "\\t" | '\\' -> Buffer.add_string buff "\\\\" | '\x00' .. '\x1F' as c -> Format.kasprintf (Buffer.add_string buff) "\\u%04x" (Char.code c) | c -> Buffer.add_char buff c) ; aux_outer (chunk_size_hint - Buffer.length buff) (index + 1)) else (* string needs escaping but later: write the non-empty non-escaped prefix and loop back *) let to_write_unescaped = next_escape - index in if bytes_left_in_buff > to_write_unescaped then ( Buffer.add_substring buff str index to_write_unescaped ; aux_outer (bytes_left_in_buff - to_write_unescaped) (index + to_write_unescaped)) else let rec aux_inner bytes_left_in_buff index to_write_unescaped continue = if bytes_left_in_buff < to_write_unescaped then ( Buffer.add_substring buff str index bytes_left_in_buff ; let s = Buffer.contents buff in Seq.Cons ( s, fun () -> aux_inner chunk_size_hint (index + bytes_left_in_buff) (to_write_unescaped - bytes_left_in_buff) continue )) else ( Buffer.add_substring buff str index to_write_unescaped ; continue (index + to_write_unescaped)) in aux_inner bytes_left_in_buff index to_write_unescaped (fun index -> aux_outer (chunk_size_hint - Buffer.length buff) index) in aux_outer (chunk_size_hint - Buffer.length buff) 0 let dump_string_literal chunk_size_hint buff literal seq = Buffer.add_char buff '"' ; dump_escaped_string chunk_size_hint buff literal (fun () -> Buffer.add_char buff '"' ; seq ()) let string_seq_of_jsonm_lexeme_seq ~newline ~chunk_size_hint (s : jsonm_lexeme Seq.t) : string Seq.t = (* we need chunk_size_hint to be reasonably high to accommodate all small literals *) let chunk_size_hint = min chunk_size_hint 16 in (* we occasionally print several characters before checking the length of the buffer (e.g., in the case of a key-value name with non-printable character at the end: 6 for one hex-encoded non-printable character in a string + 1 for the string closing double-quote + 1 for the key-value colon separator = 8 in total) (e.g., [Float.pred 0.] is ["-4.94066e-324"] which is 12 characters long). So we allocate just above chunk_size +8 to avoid the need to resize. *) let buff_size = chunk_size_hint + 16 in (* single buffer for the whole serialisation *) let buff = Buffer.create buff_size in let rec sseq first depth seq () = if Buffer.length buff >= buff_size then ( (* emit buffer content if we have reached the chunk size *) let b = Buffer.contents buff in Buffer.clear buff ; Seq.Cons (b, fun () -> (sseq [@ocaml.tailcall]) first depth seq ())) else match seq () with (* termination *) | Seq.Nil -> assert (depth = 0) ; if newline then Buffer.add_char buff '\n' ; (* value terminator: newline *) if Buffer.length buff = 0 then (* corner case: we just flushed and haven't added a newline *) Seq.Nil else let b = Buffer.contents buff in Buffer.clear buff ; Seq.Cons (b, Seq.empty) (* fixed length, small lexemes *) | Seq.Cons (`Null, seq) -> (* if we are inside an object/array (i.e., depth is > 0) and we are not the first item (i.e., first is false) then we put a delimiter character. *) if (not first) && depth > 0 then Buffer.add_char buff ',' ; (* then the value *) Buffer.add_string buff "null" ; (* and we continue with the rest. Note that depth is unchanged but first is false whatever it's original value (because whatever follows _follows_) *) (sseq [@ocaml.tailcall]) false depth seq () | Seq.Cons (`Bool true, seq) -> if (not first) && depth > 0 then Buffer.add_char buff ',' ; Buffer.add_string buff "true" ; (sseq [@ocaml.tailcall]) false depth seq () | Seq.Cons (`Bool false, seq) -> if (not first) && depth > 0 then Buffer.add_char buff ',' ; Buffer.add_string buff "false" ; (sseq [@ocaml.tailcall]) false depth seq () | Seq.Cons (`As, seq) -> if (not first) && depth > 0 then Buffer.add_char buff ',' ; Buffer.add_char buff '[' ; (* We increase the depth and mark the next value as being the first value of an array. *) (sseq [@ocaml.tailcall]) true (depth + 1) seq () | Seq.Cons (`Ae, seq) -> assert (depth > 0) ; Buffer.add_char buff ']' ; (sseq [@ocaml.tailcall]) false (depth - 1) seq () | Seq.Cons (`Os, seq) -> if (not first) && depth > 0 then Buffer.add_char buff ',' ; Buffer.add_char buff '{' ; (sseq [@ocaml.tailcall]) true (depth + 1) seq () | Seq.Cons (`Oe, seq) -> assert (depth > 0) ; Buffer.add_char buff '}' ; (sseq [@ocaml.tailcall]) false (depth - 1) seq () | Seq.Cons (`String s, seq) -> if (not first) && depth > 0 then Buffer.add_char buff ',' ; (* we delegate string literals to [dump_string_literal]. Note that we pass the rest of the sequence as a kind of continuation. This is because [dump_string_literal] may fill up the buffer and then some (depending on the size of the literal) and so it needs to be able to stick a few things in front. *) dump_string_literal chunk_size_hint buff s (fun () -> (sseq [@ocaml.tailcall]) false depth seq ()) | Seq.Cons (`Float f, seq) -> if (not first) && depth > 0 then Buffer.add_char buff ',' ; let f = string_of_float f in Buffer.add_string buff f ; (sseq [@ocaml.tailcall]) false depth seq () | Seq.Cons (`Name n, seq) -> if (not first) && depth > 0 then Buffer.add_char buff ',' ; dump_string_literal chunk_size_hint buff n (fun () -> (* set first to true to avoid printing of separator *) Buffer.add_char buff ':' ; (sseq [@ocaml.tailcall]) true depth seq ()) in sseq false 0 s let biseq_escaped_string_content buffer offset s k = let can_be_written = Bytes.length buffer - offset in if String.length s + 1 > can_be_written + Bytes.length buffer then if (* large string and.. *) (* TODO: present the string as a sequence of of blit instructions with increasing offsets *) offset < Bytes.length buffer / 2 then ( (* ..and the current buffer is almost empty: dump as much as we can on the current buffer to avoid sending a small buffer in the seq, and then use the rest of the string as its own buffer *) Bytes.blit_string s 0 buffer offset can_be_written ; let offset = offset + can_be_written in assert (offset = Bytes.length buffer) ; Seq.Cons ( (buffer, 0, offset), fun () -> let s = Bytes.unsafe_of_string s in Seq.Cons ( (s, can_be_written, Bytes.length s - can_be_written), fun () -> k 0 ) )) else (* ..and the buffer is reasonably full: put the current buffer in the seq and then the string as a single chunk *) Seq.Cons ( (buffer, 0, offset), fun () -> let s = Bytes.unsafe_of_string s in Seq.Cons ((s, 0, Bytes.length s), fun () -> k 0) ) else if String.length s + 1 <= can_be_written then ( (* we [+ 1] to account for the closing quote that will be added by [k] *) (* small string: we dump it on the buffer and continue *) Bytes.blit_string s 0 buffer offset (String.length s) ; let offset = offset + String.length s in k offset) else ( (* medium string: we blit two parts onto the buffer *) Bytes.blit_string s 0 buffer offset can_be_written ; let offset = offset + can_be_written in assert (offset = Bytes.length buffer) ; Seq.Cons ( (buffer, 0, offset), fun () -> let remain_to_be_written = String.length s - can_be_written in Bytes.blit_string s can_be_written buffer 0 remain_to_be_written ; let offset = remain_to_be_written in k offset )) let biseq_string_literal buffer offset s k = Bytes.set buffer offset '"' ; let offset = offset + 1 in let first_escape = string_needs_escaping_at 0 s in if first_escape < 0 then biseq_escaped_string_content buffer offset s (fun offset -> Bytes.set buffer offset '"' ; k (offset + 1)) else (* NOTE: offset can't be 0 because we just wrote '"', also the string cannot be empty because this is matched-for earlier *) (* TODO: optimise by escaping using the available buffer *) let s = do_escape_string s in biseq_escaped_string_content buffer offset s (fun offset -> Bytes.set buffer offset '"' ; k (offset + 1)) let blit_instructions_seq_of_jsonm_lexeme_seq ~newline ~buffer lexeme_seq = let buffer_size = Bytes.length buffer in if buffer_size < 32 then raise (Invalid_argument "Data_encoding.blit_instructions_seq_of_jsonm_lexeme_seq") ; let flush_at = buffer_size - 16 in let[@ocaml.inline] sep first depth offset = (* if we are inside an object/array (i.e., depth is > 0) and we are not the first item (i.e., first is false) then we put a delimiter character. *) if (not first) && depth > 0 then ( Bytes.set buffer offset ',' ; offset + 1) else offset in let rec biseq first depth offset seq () = if offset >= flush_at then (* emit buffer content if we have reached the chunk size *) Seq.Cons ( (buffer, 0, offset), fun () -> (biseq [@ocaml.tailcall]) first depth 0 seq () ) else match seq () with (* termination *) | Seq.Nil -> assert (depth = 0) ; let offset = if newline then ( Bytes.set buffer offset '\n' ; offset + 1) else offset in if offset = 0 then (* corner case: we just flushed (and haven't added a newline) *) Seq.Nil else Seq.Cons ((buffer, 0, offset), fun () -> Seq.Nil) (* fixed length, small lexemes *) | Seq.Cons (`Null, seq) -> let offset = sep first depth offset in Bytes.blit_string "null" 0 buffer offset 4 ; let offset = offset + 4 in (biseq [@ocaml.tailcall]) false depth offset seq () | Seq.Cons (`Bool true, seq) -> let offset = sep first depth offset in Bytes.blit_string "true" 0 buffer offset 4 ; let offset = offset + 4 in (biseq [@ocaml.tailcall]) false depth offset seq () | Seq.Cons (`Bool false, seq) -> let offset = sep first depth offset in Bytes.blit_string "false" 0 buffer offset 5 ; let offset = offset + 5 in (biseq [@ocaml.tailcall]) false depth offset seq () | Seq.Cons (`As, seq) -> let offset = sep first depth offset in Bytes.set buffer offset '[' ; let offset = offset + 1 in (biseq [@ocaml.tailcall]) true (depth + 1) offset seq () | Seq.Cons (`Ae, seq) -> Bytes.set buffer offset ']' ; let offset = offset + 1 in (biseq [@ocaml.tailcall]) false (depth - 1) offset seq () | Seq.Cons (`Os, seq) -> let offset = sep first depth offset in Bytes.set buffer offset '{' ; let offset = offset + 1 in (biseq [@ocaml.tailcall]) true (depth + 1) offset seq () | Seq.Cons (`Oe, seq) -> Bytes.set buffer offset '}' ; let offset = offset + 1 in (biseq [@ocaml.tailcall]) false (depth - 1) offset seq () | Seq.Cons (`String "", seq) -> let offset = sep first depth offset in Bytes.blit_string "\"\"" 0 buffer offset 2 ; let offset = offset + 2 in (biseq [@ocaml.tailcall]) false depth offset seq () | Seq.Cons (`String s, seq) -> let offset = sep first depth offset in (* we delegate string literals to [dump_string_literal]. Note that we pass the rest of the sequence as a kind of continuation. This is because [dump_string_literal] may fill up the buffer and then some (depending on the size of the literal) and so it needs to be able to stick a few things in front. *) biseq_string_literal buffer offset s (fun offset -> (biseq [@ocaml.tailcall]) false depth offset seq ()) | Seq.Cons (`Float f, seq) -> let offset = sep first depth offset in let f = string_of_float f in biseq_escaped_string_content buffer offset f (fun offset -> (biseq [@ocaml.tailcall]) false depth offset seq ()) | Seq.Cons (`Name n, seq) -> let offset = sep first depth offset in biseq_string_literal buffer offset n (fun offset -> if offset = buffer_size then Seq.Cons ( (buffer, 0, offset), fun () -> Bytes.set buffer 0 ':' ; let offset = 1 in (* set first to true to avoid printing of separator *) (biseq [@ocaml.tailcall]) true depth offset seq () ) else ( (* set first to true to avoid printing of separator *) Bytes.set buffer offset ':' ; let offset = offset + 1 in (biseq [@ocaml.tailcall]) true depth offset seq ())) in biseq false 0 0 lexeme_seq
sectionYPositions = computeSectionYPositions($el), 10)"
x-init="setTimeout(() => sectionYPositions = computeSectionYPositions($el), 10)"
>