1 /* hfile_gcs.c -- Google Cloud Storage backend for low-level file streams.
2
3 Copyright (C) 2016 Genome Research Ltd.
4
5 Author: John Marshall <jm18@sanger.ac.uk>
6
7 Permission is hereby granted, free of charge, to any person obtaining a copy
8 of this software and associated documentation files (the "Software"), to deal
9 in the Software without restriction, including without limitation the rights
10 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 copies of the Software, and to permit persons to whom the Software is
12 furnished to do so, subject to the following conditions:
13
14 The above copyright notice and this permission notice shall be included in
15 all copies or substantial portions of the Software.
16
17 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
22 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
23 DEALINGS IN THE SOFTWARE. */
24
25 #include <config.h>
26
27 #include <stdarg.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <errno.h>
32
33 #include "htslib/hts.h"
34 #include "htslib/kstring.h"
35 #include "hfile_internal.h"
36 #ifdef ENABLE_PLUGINS
37 #include "version.h"
38 #endif
39
40 static hFILE *
gcs_rewrite(const char * gsurl,const char * mode,int mode_has_colon,va_list * argsp)41 gcs_rewrite(const char *gsurl, const char *mode, int mode_has_colon,
42 va_list *argsp)
43 {
44 const char *bucket, *path, *access_token;
45 kstring_t mode_colon = { 0, 0, NULL };
46 kstring_t url = { 0, 0, NULL };
47 kstring_t auth_hdr = { 0, 0, NULL };
48 hFILE *fp = NULL;
49
50 // GCS URL format is gs[+SCHEME]://BUCKET/PATH
51
52 if (gsurl[2] == '+') {
53 bucket = strchr(gsurl, ':') + 1;
54 kputsn(&gsurl[3], bucket - &gsurl[3], &url);
55 }
56 else {
57 kputs("https:", &url);
58 bucket = &gsurl[3];
59 }
60 while (*bucket == '/') kputc(*bucket++, &url);
61
62 path = bucket + strcspn(bucket, "/?#");
63
64 kputsn(bucket, path - bucket, &url);
65 if (strchr(mode, 'r')) kputs(".storage-download", &url);
66 else if (strchr(mode, 'w')) kputs(".storage-upload", &url);
67 else kputs(".storage", &url);
68 kputs(".googleapis.com", &url);
69
70 kputs(path, &url);
71
72 if (hts_verbose >= 8)
73 fprintf(stderr, "[M::gcs_open] rewrote URL as %s\n", url.s);
74
75 // TODO Find the access token in a more standard way
76 access_token = getenv("GCS_OAUTH_TOKEN");
77
78 if (access_token) {
79 kputs("Authorization: Bearer ", &auth_hdr);
80 kputs(access_token, &auth_hdr);
81 }
82
83 if (argsp || auth_hdr.l > 0 || mode_has_colon) {
84 if (! mode_has_colon) {
85 kputs(mode, &mode_colon);
86 kputc(':', &mode_colon);
87 mode = mode_colon.s;
88 }
89
90 fp = hopen(url.s, mode, "va_list", argsp,
91 "httphdr", (auth_hdr.l > 0)? auth_hdr.s : NULL, NULL);
92 }
93 else
94 fp = hopen(url.s, mode);
95
96 free(mode_colon.s);
97 free(url.s);
98 free(auth_hdr.s);
99 return fp;
100 }
101
gcs_open(const char * url,const char * mode)102 static hFILE *gcs_open(const char *url, const char *mode)
103 {
104 return gcs_rewrite(url, mode, 0, NULL);
105 }
106
gcs_vopen(const char * url,const char * mode_colon,va_list args0)107 static hFILE *gcs_vopen(const char *url, const char *mode_colon, va_list args0)
108 {
109 // Need to use va_copy() as we can only take the address of an actual
110 // va_list object, not that of a parameter as its type may have decayed.
111 va_list args;
112 va_copy(args, args0);
113 hFILE *fp = gcs_rewrite(url, mode_colon, 1, &args);
114 va_end(args);
115 return fp;
116 }
117
PLUGIN_GLOBAL(hfile_plugin_init,_gcs)118 int PLUGIN_GLOBAL(hfile_plugin_init,_gcs)(struct hFILE_plugin *self)
119 {
120 static const struct hFILE_scheme_handler handler =
121 { gcs_open, hfile_always_remote, "Google Cloud Storage",
122 2000 + 50, gcs_vopen
123 };
124
125 #ifdef ENABLE_PLUGINS
126 // Embed version string for examination via strings(1) or what(1)
127 static const char id[] = "@(#)hfile_gcs plugin (htslib)\t" HTS_VERSION;
128 if (hts_verbose >= 9)
129 fprintf(stderr, "[M::hfile_gcs.init] version %s\n", strchr(id, '\t')+1);
130 #endif
131
132 self->name = "Google Cloud Storage";
133 hfile_add_scheme_handler("gs", &handler);
134 hfile_add_scheme_handler("gs+http", &handler);
135 hfile_add_scheme_handler("gs+https", &handler);
136 return 0;
137 }
138