blxextdoiapi = blxextdoiapi or {} local blxextdoiapi_module = { name = "blxextdoiapi", version = "v0.17", date = "2023/03/18", 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 \<...>{}{} 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 --