国际教育
workflow.pyisaminimalistfilebasedworkflowengine.itrunsasabackgroundprocessandcanautomatecertaintaskssuchasdeletingoldfiles
许可
3-clause BSD许可证
版权所有(c ) 2012，massimodihxdsj/pallrightsreserved。
修改，arepermittedprovidedthatthefollowingconditionsaremet :
neitherthenameofthenorthenamesofitscontributorsmaybeusedtoendorseorpromoteproductsderivedfromthissoftwarewithoutspecificpriorioriorwor
thissoftwareisprovidedbythecopyrightholdersandcontributors ' asis ' and
ANY EXPRESS OR IMPLIED WARRANTIES，INCLUDING，BUT NOT LIMITED TO，THE IMPLIED
warrantiesofmerchantabilityandfitnessforaparticularpurposeare
disclaimed.innoeventshallbeliableforany
DIRECT，INDIRECT，INCIDENTAL，SPECIAL，EXEMPLARY，OR CONSEQUENTIAL DAMAGES
(INCLUDING，BUT NOT LIMITED TO，procurementofsubstitutegoodsorservices；
LOSS OF USE，DATA，OR PROFITS； OR BUSINESS INTERRUPTION ) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY，WHETHER IN CONTRACT，STRICT LIABILITY，OR TORT
(includingnegligenceorotherwise (arisinginanywayoutoftheuseofthis ) arisinginanywayoutoftheuseofthis
软件，evenifadvisedofthepossibilityofsuchdamage。
配置向导流
createafileworkflow.configusingthesyntaxbelow
run workflow.py in that folder
工作流选项
-f the folder to monitor and process
- sthetimeintervalbetweenchecksfornewfiles
-n the current filename，defaults to $0
- xtheconfigfiletouse (workflow.config ) )。
- ythecachefiletouse (工作流. cache.db )。
- ltheoutputlogfile (电子商务控制台) )。
-d daemonizes the workflow
process-c does not start the workflow but clears a rule (see below)
workflow.config syntax
workflow.config consists of a series of rules with the following syntax
rulename: pattern [dt]: command
where
rulename is the name of the rule (cannot contain spaces).
pattern is a glob pattern for files to monitor. Avoid using *.*!
dt is a time interval (default is 1 second). Only files modified more than dt seconds ago will be considered.
command is the command to execute for each file matching pattern created more than dt seconds ago and not processed already. If the command ends in &, it is executed in background, else it blocks the workflow until completion. The name of the matching file can be referred to into the command with $0. Multiline commands can be continued with .
Lines starting with # are interpreted as comments and ignored.
Examples of rules
Delete all *.log files older than one day
delete_old_logs: *.log [1d]: rm $0
Move all *.txt files older than one hour to other folder
move_old_txt: *.txt [1h]: mv $0 otherfolder/$0
Email me when a new *.doc file is created
email_me_on_new_doc: *.doc: mail -s 'new file: $0' me@example.com < /dev/null
Process new *.dat files using a Python script
process_dat: *.dat: python process.py $0
Create a finite state machine for each *.src file
rule1: *.src [1s]: echo > $0.state.1
rule2: *.state.1 [1s]: mv $0 `expr "$0" : '(.*).1'`.2
rule3: *.state.2 [1s]: mv $0 `expr "$0" : '(.*).2'`.3
rule4: *.state.3 [1s]: rm $0
Details
When a file matches a pattern, a new process is created to execute the corresponding command. The pid of the process is saved in ..pid. This file is deleted when the process is completed. If the process fails the output log and error is saved in ..err. If the process does not fail the output is stored in ..out.
If a file has already been processed according to a certain rule, this info is stored in a file workflow.cache and it is not processed again unless:
the mtime of the file changes (for example you edit or touch the file)
the rule is cleaned up.
You can cleanup a rule with
python workflow.py -c rulename
This has the effect of creating a file .workflow.rulename.clear which the running workflow.py picks up and uses to clear the entry identified by rulename in workflow.cache, after which the rule will run again.
You can also delete the workflow.cache file. In this case all rules will run again when you restart workflow.py.
If the main workflow.py process is killed or crashes while some commands are being executed, those commands also are killed. You can find which files and rules where being processed by looking for ..pid files. If you restart workflow.py those pid files are deleted.
If a rule results in an error and a ..err is created, the file is not processed again according to the rule, unless the error file is deleted.
If a file is edited or touched and the rule runs again, the ..out will be overwritten.
Unless otherwise specified each file is processed 1s after it is last modified. It is possible that a different process is still writing the file but it is pausing more than 1s between writes (for example the file is being downloaded via a slow connection). In this case it is best to download the file with a different name than the name used for the pattern and rename the file to its proper name after the write of the file is completed. This must be handled outside of workflow. Workflow has no way of knowing when a file is completed or not.
If the workflow.config file is edited or changed, it is reloaded without the need to re-start workflow.py.