summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/tex/context/base/util-sql-sessions.lua
diff options
context:
space:
mode:
Diffstat (limited to 'Master/texmf-dist/tex/context/base/util-sql-sessions.lua')
-rw-r--r--Master/texmf-dist/tex/context/base/util-sql-sessions.lua349
1 files changed, 349 insertions, 0 deletions
diff --git a/Master/texmf-dist/tex/context/base/util-sql-sessions.lua b/Master/texmf-dist/tex/context/base/util-sql-sessions.lua
new file mode 100644
index 00000000000..76bb91962fa
--- /dev/null
+++ b/Master/texmf-dist/tex/context/base/util-sql-sessions.lua
@@ -0,0 +1,349 @@
+if not modules then modules = { } end modules ['util-sql-sessions'] = {
+ version = 1.001,
+ comment = "companion to lmx-*",
+ author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+ copyright = "PRAGMA ADE / ConTeXt Development Team",
+ license = "see context related readme files"
+}
+
+-- This is experimental code and currently part of the base installation simply
+-- because it's easier to dirtribute this way. Eventually it will be documented
+-- and the related scripts will show up as well.
+
+-- maybe store threshold in session (in seconds)
+
+local tonumber = tonumber
+local format = string.format
+local ostime, uuid, osfulltime = os.time, os.uuid, os.fulltime
+local random = math.random
+
+-- In older frameworks we kept a session table in memory. This time we
+-- follow a route where we store session data in a sql table. Each session
+-- has a token (similar to what we do on q2p and pod services), a data
+-- blob which is just a serialized lua table (we could consider a dump instead)
+-- and two times: the creation and last accessed time. The first one is handy
+-- for statistics and the second one for cleanup. Both are just numbers so that
+-- we don't have to waste code on conversions. Anyhow, we provide variants so that
+-- we can always choose what is best.
+
+local sql = utilities.sql
+local sessions = { }
+sql.sessions = sessions
+
+local trace_sql = false trackers.register("sql.sessions.trace", function(v) trace_sql = v end)
+local report = logs.reporter("sql","sessions")
+
+sessions.newtoken = sql.tokens.new
+
+local function checkeddb(presets,datatable)
+ return sql.usedatabase(presets,datatable or presets.datatable or "sessions")
+end
+
+sessions.usedb = checkeddb
+
+local template =[[
+ CREATE TABLE IF NOT EXISTS %basename% (
+ `token` varchar(50) NOT NULL,
+ `data` longtext NOT NULL,
+ `created` int(11) NOT NULL,
+ `accessed` int(11) NOT NULL,
+ UNIQUE KEY `token_unique_key` (`token`)
+ )
+ DEFAULT CHARSET = utf8 ;
+]]
+
+function sessions.createdb(presets,datatable)
+
+ local db = checkeddb(presets,datatable)
+
+ db.execute {
+ template = template,
+ variables = {
+ basename = db.basename,
+ },
+ }
+
+ report("datatable %a created in %a",db.name,db.base)
+
+ return db
+
+end
+
+local template =[[
+ DROP TABLE IF EXISTS %basename% ;
+]]
+
+function sessions.deletedb(presets,datatable)
+
+ local db = checkeddb(presets,datatable)
+
+ db.execute {
+ template = template,
+ variables = {
+ basename = db.basename,
+ },
+ }
+
+ report("datatable %a removed in %a",db.name,db.base)
+
+end
+
+local template =[[
+ INSERT INTO %basename% (
+ `token`,
+ `created`,
+ `accessed`,
+ `data`
+ ) VALUES (
+ '%token%',
+ %time%,
+ %time%,
+ '%[data]%'
+ ) ;
+]]
+
+function sessions.create(db,data)
+
+ local token = sessions.newtoken()
+ local time = ostime()
+
+ db.execute {
+ template = template,
+ variables = {
+ basename = db.basename,
+ token = token,
+ time = time,
+ data = db.serialize(data or { },"return")
+ },
+ }
+
+ if trace_sql then
+ report("created: %s at %s",token,osfulltime(time))
+ end
+
+ return {
+ token = token,
+ created = time,
+ accessed = time,
+ data = data,
+ }
+end
+
+local template =[[
+ UPDATE
+ %basename%
+ SET
+ `data` = '%[data]%',
+ `accessed` = %time%
+ WHERE
+ `token` = '%token%' ;
+]]
+
+function sessions.save(db,session)
+
+ local time = ostime()
+ local data = db.serialize(session.data or { },"return")
+ local token = session.token
+
+ session.accessed = time
+
+ db.execute {
+ template = template,
+ variables = {
+ basename = db.basename,
+ token = token,
+ time = ostime(),
+ data = data,
+ },
+ }
+
+ if trace_sql then
+ report("saved: %s at %s",token,osfulltime(time))
+ end
+
+ return session
+end
+
+local template = [[
+ UPDATE
+ %basename%
+ SET
+ `accessed` = %time%
+ WHERE
+ `token` = '%token%' ;
+]]
+
+function sessions.touch(db,token)
+
+ db.execute {
+ template = template,
+ variables = {
+ basename = db.basename,
+ token = token,
+ time = ostime(),
+ },
+ }
+
+end
+
+local template = [[
+ UPDATE
+ %basename%
+ SET
+ `accessed` = %time%
+ WHERE
+ `token` = '%token%' ;
+ SELECT
+ *
+ FROM
+ %basename%
+ WHERE
+ `token` = '%token%' ;
+]]
+
+function sessions.restore(db,token)
+
+ local records, keys = db.execute {
+ template = template,
+ variables = {
+ basename = db.basename,
+ token = token,
+ time = ostime(),
+ },
+ }
+
+ local record = records and records[1]
+
+ if record then
+ if trace_sql then
+ report("restored: %s",token)
+ end
+ record.data = db.deserialize(record.data or "")
+ return record, keys
+ elseif trace_sql then
+ report("unknown: %s",token)
+ end
+
+end
+
+local template =[[
+ DELETE FROM
+ %basename%
+ WHERE
+ `token` = '%token%' ;
+]]
+
+function sessions.remove(db,token)
+
+ db.execute {
+ template = template,
+ variables = {
+ basename = db.basename,
+ token = token,
+ },
+ }
+
+ if trace_sql then
+ report("removed: %s",token)
+ end
+
+end
+
+local template_collect_yes =[[
+ SELECT
+ *
+ FROM
+ %basename%
+ ORDER BY
+ `created` ;
+]]
+
+local template_collect_nop =[[
+ SELECT
+ `accessed`,
+ `created`,
+ `accessed`,
+ `token`
+ FROM
+ %basename%
+ ORDER BY
+ `created` ;
+]]
+
+function sessions.collect(db,nodata)
+
+ local records, keys = db.execute {
+ template = nodata and template_collect_nop or template_collect_yes,
+ variables = {
+ basename = db.basename,
+ },
+ }
+
+ if not nodata then
+ db.unpackdata(records)
+ end
+
+ if trace_sql then
+ report("collected: %s sessions",#records)
+ end
+
+ return records, keys
+
+end
+
+local template_cleanup_yes =[[
+ SELECT
+ *
+ FROM
+ %basename%
+ WHERE
+ `accessed` < %time%
+ ORDER BY
+ `created` ;
+ DELETE FROM
+ %basename%
+ WHERE
+ `accessed` < %time% ;
+]]
+
+local template_cleanup_nop =[[
+ SELECT
+ `accessed`,
+ `created`,
+ `accessed`,
+ `token`
+ FROM
+ %basename%
+ WHERE
+ `accessed` < %time%
+ ORDER BY
+ `created` ;
+ DELETE FROM
+ %basename%
+ WHERE
+ `accessed` < %time% ;
+]]
+
+function sessions.cleanupdb(db,delta,nodata)
+
+ local time = ostime()
+
+ local records, keys = db.execute {
+ template = nodata and template_cleanup_nop or template_cleanup_yes,
+ variables = {
+ basename = db.basename,
+ time = time - delta
+ },
+ }
+
+ if not nodata then
+ db.unpackdata(records)
+ end
+
+ if trace_sql then
+ report("cleaned: %s seconds before %s",delta,osfulltime(time))
+ end
+
+ return records, keys
+
+end