pocket_archive/config/app.lua

-- Application configuration.

local plpath = require "pl.path"

local ROOT = os.getenv("PKAR_ROOT")
if not ROOT then
    io.output(io.stderr)
    io.write(
        "PKAR_ROOT environment variable is not set.\n" ..
        "Data will be written to a TEMPORARY location that " ..
        "may NOT SURVIVE a reboot!"
    )
    ROOT = "/tmp/pocket_archive"
end

return {
    id = {
        -- Length in ASCII characters of system-generated IDs.
        len = 16,

        --[[ Seed for the random ID generator.

        Set this to an arbitrary integer in a test environment, so that
        resource IDs will be generated with a consistent pattern for each run
        (not when using pkar_watch, though). Note that each call to e.g.
        `pkar deposit` will generate IDs starting from the same seed and will
        overwrite resources from a previous deposit.

        If nil, os.time() will be used, which generates always different random
        IDs. This is necessary in a real-world application to avoid the above
        mentioned overwriting.
        ]]
        seed = nil,
    },
    md = {
        -- Single-valued fields. TODO rely on content model cardinality.
        single_values = {
            ["content_type"] = true,
            ["label"] = true,
            ["archive_path"] = true,
            ["source_path"] = true,
        },

        -- Map of data types in prop definitions to RDF literal types.
        -- Non-mapped items are set to `xsd:string`.
        datatypes = {
            integer = "xsd:integer",
            decimal = "xsd:decimal",
            float = "xsd:double",
            boolean = "xsd:boolean",
            datetime = "xsd:datetime",
        }
    },
    fs = {
        -- Base path to write opaque resources.
        ores_path = os.getenv("PKAR_ORES") or plpath.join(ROOT, "data", "ores"),
        -- Base path of LSUP store for descriptive resources (RDF).
        dres_path = os.getenv("PKAR_DRES") or plpath.join(ROOT, "data", "dres"),

        -- How many bytes to read when handling files. Adjust to memory
        -- availability.
        stream_chunk_size = 1024 ^ 2,  -- 1Mb
    },

    -- Namespace prefixes to populate the Pocket Archive NS map.
    namespace = {
        b2 = "blake2:",
        dc = "http://purl.org/dc/terms/",
        foaf = "http://xmlns.com/foaf/0.1/",
        par = "http://id.pkar.knowledgetx.com/resource/",
        pas = "http://id.pkar.knowledgetx.com/schema#",
        premis = "http://id.loc.gov/vocabulary/preservation/",
        rdf = "http://www.w3.org/1999/02/22-rdf-syntax-ns#",
        rdfs = "http://www.w3.org/2000/01/rdf-schema#",
        sub = "http://id.pkar.knowledgetx.com/submission/",
        xsd = "http://www.w3.org/2001/XMLSchema#",
    },

    -- Static site (presentation) generation settings.
    pres_gen = {
        title = "Pocket Archive demo site",
        out_dir = plpath.join(ROOT, "out", "pres"),
        max_homepage_items = 12,
    },

    -- Content model doc generation settings.
    cmdoc_gen = {
        out_dir = plpath.join(ROOT, "out", "cmdoc"),
    },
}