1
2 /*
3 * Copyright (C) Igor Sysoev
4 * Copyright (C) Nginx, Inc.
5 */
6
7
8 #include <ngx_config.h>
9 #include <ngx_core.h>
10 #include <ngx_http.h>
11
12
13 typedef struct {
14 ngx_http_upstream_conf_t upstream;
15 ngx_int_t index;
16 ngx_uint_t gzip_flag;
17 } ngx_http_memcached_loc_conf_t;
18
19
20 typedef struct {
21 size_t rest;
22 ngx_http_request_t *request;
23 ngx_str_t key;
24 } ngx_http_memcached_ctx_t;
25
26
27 static ngx_int_t ngx_http_memcached_create_request(ngx_http_request_t *r);
28 static ngx_int_t ngx_http_memcached_reinit_request(ngx_http_request_t *r);
29 static ngx_int_t ngx_http_memcached_process_header(ngx_http_request_t *r);
30 static ngx_int_t ngx_http_memcached_filter_init(void *data);
31 static ngx_int_t ngx_http_memcached_filter(void *data, ssize_t bytes);
32 static void ngx_http_memcached_abort_request(ngx_http_request_t *r);
33 static void ngx_http_memcached_finalize_request(ngx_http_request_t *r,
34 ngx_int_t rc);
35
36 static void *ngx_http_memcached_create_loc_conf(ngx_conf_t *cf);
37 static char *ngx_http_memcached_merge_loc_conf(ngx_conf_t *cf,
38 void *parent, void *child);
39
40 static char *ngx_http_memcached_pass(ngx_conf_t *cf, ngx_command_t *cmd,
41 void *conf);
42
43
44 static ngx_conf_bitmask_t ngx_http_memcached_next_upstream_masks[] = {
45 { ngx_string("error"), NGX_HTTP_UPSTREAM_FT_ERROR },
46 { ngx_string("timeout"), NGX_HTTP_UPSTREAM_FT_TIMEOUT },
47 { ngx_string("invalid_response"), NGX_HTTP_UPSTREAM_FT_INVALID_HEADER },
48 { ngx_string("not_found"), NGX_HTTP_UPSTREAM_FT_HTTP_404 },
49 { ngx_string("off"), NGX_HTTP_UPSTREAM_FT_OFF },
50 { ngx_null_string, 0 }
51 };
52
53
54 static ngx_command_t ngx_http_memcached_commands[] = {
55
56 { ngx_string("memcached_pass"),
57 NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF|NGX_CONF_TAKE1,
58 ngx_http_memcached_pass,
59 NGX_HTTP_LOC_CONF_OFFSET,
60 0,
61 NULL },
62
63 { ngx_string("memcached_bind"),
64 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
65 ngx_http_upstream_bind_set_slot,
66 NGX_HTTP_LOC_CONF_OFFSET,
67 offsetof(ngx_http_memcached_loc_conf_t, upstream.local),
68 NULL },
69
70 { ngx_string("memcached_connect_timeout"),
71 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
72 ngx_conf_set_msec_slot,
73 NGX_HTTP_LOC_CONF_OFFSET,
74 offsetof(ngx_http_memcached_loc_conf_t, upstream.connect_timeout),
75 NULL },
76
77 { ngx_string("memcached_send_timeout"),
78 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
79 ngx_conf_set_msec_slot,
80 NGX_HTTP_LOC_CONF_OFFSET,
81 offsetof(ngx_http_memcached_loc_conf_t, upstream.send_timeout),
82 NULL },
83
84 { ngx_string("memcached_buffer_size"),
85 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
86 ngx_conf_set_size_slot,
87 NGX_HTTP_LOC_CONF_OFFSET,
88 offsetof(ngx_http_memcached_loc_conf_t, upstream.buffer_size),
89 NULL },
90
91 { ngx_string("memcached_read_timeout"),
92 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
93 ngx_conf_set_msec_slot,
94 NGX_HTTP_LOC_CONF_OFFSET,
95 offsetof(ngx_http_memcached_loc_conf_t, upstream.read_timeout),
96 NULL },
97
98 { ngx_string("memcached_next_upstream"),
99 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
100 ngx_conf_set_bitmask_slot,
101 NGX_HTTP_LOC_CONF_OFFSET,
102 offsetof(ngx_http_memcached_loc_conf_t, upstream.next_upstream),
103 &ngx_http_memcached_next_upstream_masks },
104
105 { ngx_string("memcached_gzip_flag"),
106 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
107 ngx_conf_set_num_slot,
108 NGX_HTTP_LOC_CONF_OFFSET,
109 offsetof(ngx_http_memcached_loc_conf_t, gzip_flag),
110 NULL },
111
112 ngx_null_command
113 };
114
115
116 static ngx_http_module_t ngx_http_memcached_module_ctx = {
117 NULL, /* preconfiguration */
118 NULL, /* postconfiguration */
119
120 NULL, /* create main configuration */
121 NULL, /* init main configuration */
122
123 NULL, /* create server configuration */
124 NULL, /* merge server configuration */
125
126 ngx_http_memcached_create_loc_conf, /* create location configuration */
127 ngx_http_memcached_merge_loc_conf /* merge location configuration */
128 };
129
130
131 ngx_module_t ngx_http_memcached_module = {
132 NGX_MODULE_V1,
133 &ngx_http_memcached_module_ctx, /* module context */
134 ngx_http_memcached_commands, /* module directives */
135 NGX_HTTP_MODULE, /* module type */
136 NULL, /* init master */
137 NULL, /* init module */
138 NULL, /* init process */
139 NULL, /* init thread */
140 NULL, /* exit thread */
141 NULL, /* exit process */
142 NULL, /* exit master */
143 NGX_MODULE_V1_PADDING
144 };
145
146
147 static ngx_str_t ngx_http_memcached_key = ngx_string("memcached_key");
148
149
150 #define NGX_HTTP_MEMCACHED_END (sizeof(ngx_http_memcached_end) - 1)
151 static u_char ngx_http_memcached_end[] = CRLF "END" CRLF;
152
153
154 static ngx_int_t
155 ngx_http_memcached_handler(ngx_http_request_t *r)
156 {
157 ngx_int_t rc;
158 ngx_http_upstream_t *u;
159 ngx_http_memcached_ctx_t *ctx;
160 ngx_http_memcached_loc_conf_t *mlcf;
161
162 if (!(r->method & (NGX_HTTP_GET|NGX_HTTP_HEAD))) {
163 return NGX_HTTP_NOT_ALLOWED;
164 }
165
166 rc = ngx_http_discard_request_body(r);
167
168 if (rc != NGX_OK) {
169 return rc;
170 }
171
172 if (ngx_http_set_content_type(r) != NGX_OK) {
173 return NGX_HTTP_INTERNAL_SERVER_ERROR;
174 }
175
176 if (ngx_http_upstream_create(r) != NGX_OK) {
177 return NGX_HTTP_INTERNAL_SERVER_ERROR;
178 }
179
180 u = r->upstream;
181
182 ngx_str_set(&u->schema, "memcached://");
183 u->output.tag = (ngx_buf_tag_t) &ngx_http_memcached_module;
184
185 mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module);
186
187 u->conf = &mlcf->upstream;
188
189 u->create_request = ngx_http_memcached_create_request;
190 u->reinit_request = ngx_http_memcached_reinit_request;
191 u->process_header = ngx_http_memcached_process_header;
192 u->abort_request = ngx_http_memcached_abort_request;
193 u->finalize_request = ngx_http_memcached_finalize_request;
194
195 ctx = ngx_palloc(r->pool, sizeof(ngx_http_memcached_ctx_t));
196 if (ctx == NULL) {
197 return NGX_HTTP_INTERNAL_SERVER_ERROR;
198 }
199
200 ctx->rest = NGX_HTTP_MEMCACHED_END;
201 ctx->request = r;
202
203 ngx_http_set_ctx(r, ctx, ngx_http_memcached_module);
204
205 u->input_filter_init = ngx_http_memcached_filter_init;
206 u->input_filter = ngx_http_memcached_filter;
207 u->input_filter_ctx = ctx;
208
209 r->main->count++;
210
211 ngx_http_upstream_init(r);
212
213 return NGX_DONE;
214 }
215
216
217 static ngx_int_t
218 ngx_http_memcached_create_request(ngx_http_request_t *r)
219 {
220 size_t len;
221 uintptr_t escape;
222 ngx_buf_t *b;
223 ngx_chain_t *cl;
224 ngx_http_memcached_ctx_t *ctx;
225 ngx_http_variable_value_t *vv;
226 ngx_http_memcached_loc_conf_t *mlcf;
227
228 mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module);
229
230 vv = ngx_http_get_indexed_variable(r, mlcf->index);
231
232 if (vv == NULL || vv->not_found || vv->len == 0) {
233 ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
234 "the \"$memcached_key\" variable is not set");
235 return NGX_ERROR;
236 }
237
238 escape = 2 * ngx_escape_uri(NULL, vv->data, vv->len, NGX_ESCAPE_MEMCACHED);
239
240 len = sizeof("get ") - 1 + vv->len + escape + sizeof(CRLF) - 1;
241
242 b = ngx_create_temp_buf(r->pool, len);
243 if (b == NULL) {
244 return NGX_ERROR;
245 }
246
247 cl = ngx_alloc_chain_link(r->pool);
248 if (cl == NULL) {
249 return NGX_ERROR;
250 }
251
252 cl->buf = b;
253 cl->next = NULL;
254
255 r->upstream->request_bufs = cl;
256
257 *b->last++ = 'g'; *b->last++ = 'e'; *b->last++ = 't'; *b->last++ = ' ';
258
259 ctx = ngx_http_get_module_ctx(r, ngx_http_memcached_module);
260
261 ctx->key.data = b->last;
262
263 if (escape == 0) {
264 b->last = ngx_copy(b->last, vv->data, vv->len);
265
266 } else {
267 b->last = (u_char *) ngx_escape_uri(b->last, vv->data, vv->len,
268 NGX_ESCAPE_MEMCACHED);
269 }
270
271 ctx->key.len = b->last - ctx->key.data;
272
273 ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
274 "http memcached request: \"%V\"", &ctx->key);
275
276 *b->last++ = CR; *b->last++ = LF;
277
278 return NGX_OK;
279 }
280
281
282 static ngx_int_t
283 ngx_http_memcached_reinit_request(ngx_http_request_t *r)
284 {
285 return NGX_OK;
286 }
287
288
289 static ngx_int_t
290 ngx_http_memcached_process_header(ngx_http_request_t *r)
291 {
292 u_char *p, *start;
293 ngx_str_t line;
294 ngx_uint_t flags;
295 ngx_table_elt_t *h;
296 ngx_http_upstream_t *u;
297 ngx_http_memcached_ctx_t *ctx;
298 ngx_http_memcached_loc_conf_t *mlcf;
299
300 u = r->upstream;
301
302 for (p = u->buffer.pos; p < u->buffer.last; p++) {
303 if (*p == LF) {
304 goto found;
305 }
306 }
307
308 return NGX_AGAIN;
309
310 found:
311
312 *p = '\0';
313
314 line.len = p - u->buffer.pos - 1;
315 line.data = u->buffer.pos;
316
317 ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
318 "memcached: \"%V\"", &line);
319
320 p = u->buffer.pos;
321
322 ctx = ngx_http_get_module_ctx(r, ngx_http_memcached_module);
323 mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module);
324
325 if (ngx_strncmp(p, "VALUE ", sizeof("VALUE ") - 1) == 0) {
326
327 p += sizeof("VALUE ") - 1;
328
329 if (ngx_strncmp(p, ctx->key.data, ctx->key.len) != 0) {
330 ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
331 "memcached sent invalid key in response \"%V\" "
332 "for key \"%V\"",
333 &line, &ctx->key);
334
335 return NGX_HTTP_UPSTREAM_INVALID_HEADER;
336 }
337
338 p += ctx->key.len;
339
340 if (*p++ != ' ') {
341 goto no_valid;
342 }
343
344 /* flags */
345
346 start = p;
347
348 while (*p) {
349 if (*p++ == ' ') {
350 if (mlcf->gzip_flag) {
351 goto flags;
352 } else {
353 goto length;
354 }
355 }
356 }
357
358 goto no_valid;
359
360 flags:
361
362 flags = ngx_atoi(start, p - start - 1);
363
364 if (flags == (ngx_uint_t) NGX_ERROR) {
365 ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
366 "memcached sent invalid flags in response \"%V\" "
367 "for key \"%V\"",
368 &line, &ctx->key);
369 return NGX_HTTP_UPSTREAM_INVALID_HEADER;
370 }
371
372 if (flags & mlcf->gzip_flag) {
373 h = ngx_list_push(&r->headers_out.headers);
374 if (h == NULL) {
375 return NGX_ERROR;
376 }
377
378 h->hash = 1;
379 h->key.len = sizeof("Content-Encoding") - 1;
380 h->key.data = (u_char *) "Content-Encoding";
381 h->value.len = sizeof("gzip") - 1;
382 h->value.data = (u_char *) "gzip";
383
384 r->headers_out.content_encoding = h;
385 }
386
387 length:
388
389 start = p;
390
391 while (*p && *p++ != CR) { /* void */ }
392
393 u->headers_in.content_length_n = ngx_atoof(start, p - start - 1);
394 if (u->headers_in.content_length_n == -1) {
395 ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
396 "memcached sent invalid length in response \"%V\" "
397 "for key \"%V\"",
398 &line, &ctx->key);
399 return NGX_HTTP_UPSTREAM_INVALID_HEADER;
400 }
401
402 u->headers_in.status_n = 200;
403 u->state->status = 200;
404 u->buffer.pos = p + 1;
405
406 return NGX_OK;
407 }
408
409 if (ngx_strcmp(p, "END\x0d") == 0) {
410 ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
411 "key: \"%V\" was not found by memcached", &ctx->key);
412
413 u->headers_in.status_n = 404;
414 u->state->status = 404;
415 u->keepalive = 1;
416
417 return NGX_OK;
418 }
419
420 no_valid:
421
422 ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
423 "memcached sent invalid response: \"%V\"", &line);
424
425 return NGX_HTTP_UPSTREAM_INVALID_HEADER;
426 }
427
428
429 static ngx_int_t
430 ngx_http_memcached_filter_init(void *data)
431 {
432 ngx_http_memcached_ctx_t *ctx = data;
433
434 ngx_http_upstream_t *u;
435
436 u = ctx->request->upstream;
437
438 u->length += NGX_HTTP_MEMCACHED_END;
439
440 return NGX_OK;
441 }
442
443
444 static ngx_int_t
445 ngx_http_memcached_filter(void *data, ssize_t bytes)
446 {
447 ngx_http_memcached_ctx_t *ctx = data;
448
449 u_char *last;
450 ngx_buf_t *b;
451 ngx_chain_t *cl, **ll;
452 ngx_http_upstream_t *u;
453
454 u = ctx->request->upstream;
455 b = &u->buffer;
456
457 if (u->length == (ssize_t) ctx->rest) {
458
459 if (ngx_strncmp(b->last,
460 ngx_http_memcached_end + NGX_HTTP_MEMCACHED_END - ctx->rest,
461 bytes)
462 != 0)
463 {
464 ngx_log_error(NGX_LOG_ERR, ctx->request->connection->log, 0,
465 "memcached sent invalid trailer");
466
467 u->length = 0;
468 ctx->rest = 0;
469
470 return NGX_OK;
471 }
472
473 u->length -= bytes;
474 ctx->rest -= bytes;
475
476 if (u->length == 0) {
477 u->keepalive = 1;
478 }
479
480 return NGX_OK;
481 }
482
483 for (cl = u->out_bufs, ll = &u->out_bufs; cl; cl = cl->next) {
484 ll = &cl->next;
485 }
486
487 cl = ngx_chain_get_free_buf(ctx->request->pool, &u->free_bufs);
488 if (cl == NULL) {
489 return NGX_ERROR;
490 }
491
492 cl->buf->flush = 1;
493 cl->buf->memory = 1;
494
495 *ll = cl;
496
497 last = b->last;
498 cl->buf->pos = last;
499 b->last += bytes;
500 cl->buf->last = b->last;
501 cl->buf->tag = u->output.tag;
502
503 ngx_log_debug4(NGX_LOG_DEBUG_HTTP, ctx->request->connection->log, 0,
504 "memcached filter bytes:%z size:%z length:%z rest:%z",
505 bytes, b->last - b->pos, u->length, ctx->rest);
506
507 if (bytes <= (ssize_t) (u->length - NGX_HTTP_MEMCACHED_END)) {
508 u->length -= bytes;
509 return NGX_OK;
510 }
511
512 last += u->length - NGX_HTTP_MEMCACHED_END;
513
514 if (ngx_strncmp(last, ngx_http_memcached_end, b->last - last) != 0) {
515 ngx_log_error(NGX_LOG_ERR, ctx->request->connection->log, 0,
516 "memcached sent invalid trailer");
517
518 b->last = last;
519 cl->buf->last = last;
520 u->length = 0;
521 ctx->rest = 0;
522
523 return NGX_OK;
524 }
525
526 ctx->rest -= b->last - last;
527 b->last = last;
528 cl->buf->last = last;
529 u->length = ctx->rest;
530
531 if (u->length == 0) {
532 u->keepalive = 1;
533 }
534
535 return NGX_OK;
536 }
537
538
539 static void
540 ngx_http_memcached_abort_request(ngx_http_request_t *r)
541 {
542 ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
543 "abort http memcached request");
544 return;
545 }
546
547
548 static void
549 ngx_http_memcached_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
550 {
551 ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
552 "finalize http memcached request");
553 return;
554 }
555
556
557 static void *
558 ngx_http_memcached_create_loc_conf(ngx_conf_t *cf)
559 {
560 ngx_http_memcached_loc_conf_t *conf;
561
562 conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_memcached_loc_conf_t));
563 if (conf == NULL) {
564 return NULL;
565 }
566
567 /*
568 * set by ngx_pcalloc():
569 *
570 * conf->upstream.bufs.num = 0;
571 * conf->upstream.next_upstream = 0;
572 * conf->upstream.temp_path = NULL;
573 * conf->upstream.uri = { 0, NULL };
574 * conf->upstream.location = NULL;
575 */
576
577 conf->upstream.local = NGX_CONF_UNSET_PTR;
578 conf->upstream.connect_timeout = NGX_CONF_UNSET_MSEC;
579 conf->upstream.send_timeout = NGX_CONF_UNSET_MSEC;
580 conf->upstream.read_timeout = NGX_CONF_UNSET_MSEC;
581
582 conf->upstream.buffer_size = NGX_CONF_UNSET_SIZE;
583
584 /* the hardcoded values */
585 conf->upstream.cyclic_temp_file = 0;
586 conf->upstream.buffering = 0;
587 conf->upstream.ignore_client_abort = 0;
588 conf->upstream.send_lowat = 0;
589 conf->upstream.bufs.num = 0;
590 conf->upstream.busy_buffers_size = 0;
591 conf->upstream.max_temp_file_size = 0;
592 conf->upstream.temp_file_write_size = 0;
593 conf->upstream.intercept_errors = 1;
594 conf->upstream.intercept_404 = 1;
595 conf->upstream.pass_request_headers = 0;
596 conf->upstream.pass_request_body = 0;
597
598 conf->index = NGX_CONF_UNSET;
599 conf->gzip_flag = NGX_CONF_UNSET_UINT;
600
601 return conf;
602 }
603
604
605 static char *
606 ngx_http_memcached_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
607 {
608 ngx_http_memcached_loc_conf_t *prev = parent;
609 ngx_http_memcached_loc_conf_t *conf = child;
610
611 ngx_conf_merge_ptr_value(conf->upstream.local,
612 prev->upstream.local, NULL);
613
614 ngx_conf_merge_msec_value(conf->upstream.connect_timeout,
615 prev->upstream.connect_timeout, 60000);
616
617 ngx_conf_merge_msec_value(conf->upstream.send_timeout,
618 prev->upstream.send_timeout, 60000);
619
620 ngx_conf_merge_msec_value(conf->upstream.read_timeout,
621 prev->upstream.read_timeout, 60000);
622
623 ngx_conf_merge_size_value(conf->upstream.buffer_size,
624 prev->upstream.buffer_size,
625 (size_t) ngx_pagesize);
626
627 ngx_conf_merge_bitmask_value(conf->upstream.next_upstream,
628 prev->upstream.next_upstream,
629 (NGX_CONF_BITMASK_SET
630 |NGX_HTTP_UPSTREAM_FT_ERROR
631 |NGX_HTTP_UPSTREAM_FT_TIMEOUT));
632
633 if (conf->upstream.next_upstream & NGX_HTTP_UPSTREAM_FT_OFF) {
634 conf->upstream.next_upstream = NGX_CONF_BITMASK_SET
635 |NGX_HTTP_UPSTREAM_FT_OFF;
636 }
637
638 if (conf->upstream.upstream == NULL) {
639 conf->upstream.upstream = prev->upstream.upstream;
640 }
641
642 if (conf->index == NGX_CONF_UNSET) {
643 conf->index = prev->index;
644 }
645
646 ngx_conf_merge_uint_value(conf->gzip_flag, prev->gzip_flag, 0);
647
648 return NGX_CONF_OK;
649 }
650
651
652 static char *
653 ngx_http_memcached_pass(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
654 {
655 ngx_http_memcached_loc_conf_t *mlcf = conf;
656
657 ngx_str_t *value;
658 ngx_url_t u;
659 ngx_http_core_loc_conf_t *clcf;
660
661 if (mlcf->upstream.upstream) {
662 return "is duplicate";
663 }
664
665 value = cf->args->elts;
666
667 ngx_memzero(&u, sizeof(ngx_url_t));
668
669 u.url = value[1];
670 u.no_resolve = 1;
671
672 mlcf->upstream.upstream = ngx_http_upstream_add(cf, &u, 0);
673 if (mlcf->upstream.upstream == NULL) {
674 return NGX_CONF_ERROR;
675 }
676
677 clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
678
679 clcf->handler = ngx_http_memcached_handler;
680
681 if (clcf->name.data[clcf->name.len - 1] == '/') {
682 clcf->auto_redirect = 1;
683 }
684
685 mlcf->index = ngx_http_get_variable_index(cf, &ngx_http_memcached_key);
686
687 if (mlcf->index == NGX_ERROR) {
688 return NGX_CONF_ERROR;
689 }
690
691 return NGX_CONF_OK;
692 }
693
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