summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/tex/latex/biblatex-ext/blxextdoiapi.lua
blob: 4218deef6a45483d3bed2f87838292c2da3b694f (plain)
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
blxextdoiapi = blxextdoiapi or {}

local blxextdoiapi_module = {
  name          = "blxextdoiapi",
  version       = "v0.13",
  date          = "2021/06/08",
  description   = "Obtain open access information from DOI via unpaywall.org",
  author        = "Moritz Wemheuer",
  license       = "LPPL v1.3c",
  url           = "https://github.com/moewew/biblatex-ext/",
}
-- inspired by Eric Marsden's answer to https://tex.stackexchange.com/q/459449/


-- luatexbase's luatexbase.provides_module returns the loggers directly
local err, warn, info, log = luatexbase.provides_module(blxextdoiapi_module)

-- Does it even make sense to try and make use of the extra luatexbase stuff
-- from luatexbase.sty? Since we don't want to assume that package in general,
-- we have to manually recode it anyway...

-- for ltluatex's luatexbase.provides_module we need to construct the loggers
local error   = err  or
  (function (s,...)
     return luatexbase.module_error(blxextdoiapi_module.name, s:format(...))
   end)
local warning = warn or
  (function (s,...)
     return luatexbase.module_warning(blxextdoiapi_module.name, s:format(...))
   end)
local info    = info or
  (function (s,...)
     return luatexbase.module_info(blxextdoiapi_module.name, s:format(...))
   end)
local log     = log  or
  (function (s,...)
     return luatexbase.module_info(blxextdoiapi_module.name, s:format(...))
   end)


local http        = require("socket.http")
local url         = socket.url or require("socket.url") --- #17, LuaTeX 1.07
local json        = utilities.json
local os_time     = os.time
local os_date     = os.date
local os_difftime = os.difftime
local gsub        = string.gsub
local texwrite    = tex.write

-- cf. fontspec.lua and microtype.lua
-- http://mirrors.ctan.org/macros/latex/contrib/fontspec/fontspec-lua.dtx
-- http://mirrors.ctan.org/macros/latex/contrib/microtype/microtype.dtx
-- as well as luatexja.lua (luatexbase.catcodetables['latex-package'])
-- http://mirrors.ctan.org/macros/luatex/generic/luatexja/src/luatexja.lua
-- and luaotfload-auxiliary.lua (luatexbase.catcodetables["latex-package"])
-- http://mirrors.ctan.org/macros/luatex/generic/luaotfload/luaotfload-auxiliary.lua
local catpackage
if luatexbase.catcodetables then
  catpackage = luatexbase.catcodetables["latex-package"]          -- luatexbase
else
  catpackage = luatexbase.registernumber("catcodetable@atletter") -- ltluatex
end

local function texsprint(s)
  tex.sprint(catpackage, s)
end

-- global database of DOIs
-- is going to be loaded from \jobname.oai beforehand if the file exists
oadb = oadb or {}

-- parse YYYY-MM-DD date as string (UTC time!)
-- os.time is usually local time, hence the utc_offset to get UTC
-- see also https://stackoverflow.com/q/4105012
local function ymdstr_to_date(date_str)
  local date_pattern = "(%d+)-(%d+)-(%d+)"
  local utc_offset = os_difftime(os_time(), os_time(os_date("!*t")))
  local year, month, day = date_str:match(date_pattern)

  if year and month and day then
    return os_time({year = year, month = month, day = day, sec=utc_offset})
  end

  return nil
end

local TODAY_STR = os_date("!%Y-%m-%d")
local TODAY = ymdstr_to_date(TODAY_STR)

local SECONDS_PER_DAY = 86400

-- info in oadb expires after blxextdoiapi.cache_expire days
-- if the info is older than that is_recent_info will return false
-- can be set with \SetDOIAPICacheExpiration
local cache_expire = 7

-- this includes a test if there is info at all
local function is_recent_info(doi, days, api)
  if oadb[doi] and oadb[doi]["cache_date_" .. api] then
    return os_difftime(TODAY, ymdstr_to_date(oadb[doi]["cache_date_" .. api]))
           < days * SECONDS_PER_DAY
  end

  return false
end

local function query_json_api(req_url)
  body, code, headers = http.request(req_url)
  if body then
    -- JSON escapes don't quite work for Lua
    -- https://tools.ietf.org/html/rfc8259, section 7
    -- http://lua-users.org/lists/lua-l/2017-04/msg00100.html
    -- query DOI 10.1371/journal.pbio.2005099 from Unpaywall
    -- to see what goes wrong
    body = body:gsub("\\u(%x%x%x%x)","\\u{%1}")
    return json.tolua(body), code
  end

  return nil, code
end

-- DISABLED for now :-(
-- doi.org only serves via HTTPS, but Lua(TeX) has no built-in
-- support for SLL at the moment, so we can't query the API
-- as we only get 301 response
--[[
local function get_doi_info(doi)
  local req_url = "http://doi.org/api/handles/" .. url.escape(doi)
  local doi_info, code  = query_json_api(req_url)

  if doi_info then
    oadb[doi] = oadb[doi] or {}
    oadb[doi]["cache_date_doi"] = TODAY_STR
    oadb[doi]["is_valid"] = (doi_info["responseCode"] == 1)
    info("Successfully queried doi.org for info on\n" .. doi)
    return oadb[doi]["is_valid"]
  end

  warning("Failed to obtain DOI info\nfrom doi.org for\n"
          .. doi .. "\nerror code " .. code)
  return false
end

local function is_valid_doi(doi)
  if is_recent_info(doi, blxextdoiapi.cache_expire, "doi") then
    return oadb[doi]["is_valid"]
  end

  return get_doi_info(doi)
end
]]--

-- email is required, error out if not given
-- Unfortunately, this gives a weird Lua dump as well and one has to scroll
-- up to see the error, but it felt like cheating shoehorning in
-- a usual TeX error instead of the generic LuaTeX error provided by ltluatex.
-- Only makes sense if the DOI is valid.
local function get_unpaywall_info(doi)
  -- if not is_valid_doi(doi) then
  --   return nil
  -- elseif not blxextdoiapi.mail or blxextdoiapi.mail == "" then
  if not blxextdoiapi.mail or blxextdoiapi.mail == "" then
    error("No mail address supplied.\n" ..
          "You must give a valid email address\n" ..
          "to be able to use the Unpaywall API\n")
    return nil
  end

  local req_url = "http://api.unpaywall.org/v2/" .. doi
                  .. "?email=" .. blxextdoiapi.mail
  local upw_info, code = query_json_api(req_url)

  if code == 200 and upw_info then
    oadb[doi] = oadb[doi] or {}
    oadb[doi]["cache_date_upw"] = TODAY_STR
    -- Don't read "is_oa", we go to the URL directly.
    if upw_info["best_oa_location"] then
      oadb[doi]["oa_url"] = upw_info["best_oa_location"]["url_for_landing_page"]
                            or upw_info["best_oa_location"]["url"]
                            or upw_info["best_oa_location"]["url_for_pdf"]
      -- As it turns out url_for_landing_page might be null
      -- even though there is a url and a url_for_pdf.
      -- http://unpaywall.org/data-format does not explicitly list
      -- url_for_landing_page as String|Null like other null-able objects.
      -- But request 10.1007/s00163-016-0235-2 to see this issue
      -- (at least updated: "2018-07-28T00:37:18.524676").
      -- I don't understand why Unpaywall returns two objects in the first place
      -- they are clearly the same. Yet the one identified as 'best' has a
      -- longer, weird URL and no landing page. It was probably chosen because
      -- it is marked as having been updated more recently.
    else
      oadb[doi]["oa_url"] = nil
    end
    info("Successfully queried unpaywall.org\n"
         .. "for info on\n" .. doi)
    return oadb[doi]["oa_url"]
  end

  warning("Failed to obtain open access info\n"
          .. "from unpaywall.org for DOI\n" .. doi .. "\n"
          .. "error code: " .. code)
  return nil
end


local function get_openaccess_url(doi)
  if is_recent_info(doi, blxextdoiapi.cache_expire, "upw") then
    return oadb[doi]["oa_url"]
  end

  return get_unpaywall_info(doi)
end

-- Has \url hard-coded, people probably shouldn't be using this,
-- but it's documented now
local function get_openaccess_url_tex(doi)
  local oa_url = get_openaccess_url(doi)
  if oa_url then
    texsprint("\\url{")
    texwrite(oa_url)
    texsprint("}")
  end
end


-- For TeX. I'd have liked this better in the .sty, but the whole \ escape
-- malarkey made that a pain, so the function is here now.
local function assign_openaccess_url_to(macro, doi)
  local oa_url = get_openaccess_url(doi)
  if oa_url then
    texsprint("\\def"..macro.."{")
    texwrite(oa_url)
    texsprint("}")
  end
end

-- returns false if there is no open access URL since the RHS ~= nil
local function openaccess_url_is_doi(doi)
  return get_openaccess_url(doi) == "https://doi.org/" .. doi
end

local function is_openaccess(doi)
  return get_openaccess_url(doi) ~= nil
end


-- make conditionals usable as \<...>{<true>}{<false>} directly
local function texify_conditional(cond)
  if cond then
    texsprint("\\@firstoftwo")
  else
    texsprint("\\@secondoftwo")
  end
end

-- mail is not exported, we just expect the user to set it
return {
  module                   = module,
  cache_expire             = cache_expire,
  -- is_valid_doi             = is_valid_doi,
  is_openaccess            = is_openaccess,
  get_openaccess_url       = get_openaccess_url,
  get_openaccess_url_tex   = get_openaccess_url_tex,
  assign_openaccess_url_to = assign_openaccess_url_to,
  openaccess_url_is_doi    = openaccess_url_is_doi,
  texify_conditional       = texify_conditional,
}

--
-- This file is part of the biblatex-ext bundle.
-- biblatex-ext is released under the LaTeX Project Public License v1.3c
-- or later.
--
-- A complete list of files included in that package can be found in README.md
-- or - failing that - in ext-standard.bbx.
--
-- Official releases of this package are on CTAN
--   https://www.ctan.org/pkg/biblatex-ext
-- development takes place on GitHub
--   https://github.com/moewew/biblatex-ext
--