Joint IDC / Tidelift Webinar: The future of open source software support.
pipemill
Pipemill is a cli utility for manipulating process streams with JavaScript. Pipemill is akin to pjs but gives a complete degree of control over what code is evaluated in the context of the stream.
Like UNIX streams pipemill chains the process stdin between a series of JavaScript pipeline expressions.
#split stdin into new lines
ls -tlr | pipemill -p 'return stdin.split("\n")' [
'drwxr-xr-x@ 20 user staff 680 Aug 8 21:45 node_modules',
'drwxr-xr-x@ 20 user staff 680 Aug 8 21:45 package.json'
]# split stdin into new lines then filter out node_modules
ls -tlr | pipemill -p 'return stdin.split("\n")' \
-p 'return _.filter(stdin, function (item){return ~item.indexOf("package")});' [
'drwxr-xr-x@ 20 user staff 680 Aug 8 21:45 package.json'
]# save your javascript pipeline with an argument and reuse by passing in an expression
pipemill save filter -p 'return stdin.split("\n")' \
-p 'return _.filter(stdin, function (item){return ~item.indexOf($0)});'
ls -tlr | pipemill -p 'pipelines.filter("package")' [
'drwxr-xr-x@ 20 user staff 680 Aug 8 21:45 package.json'
]# add optional arguments and reuse pipelines as first class citizens
pipemill -p 'return stdin.split($0 || "\n")' --save split
# compose large pipelines as functions of smaller saved pipelines
pipemill save splitAndFilter -p 'pipelines.split($0)' -p 'return stdin.filter(Boolean)'
pipemill -p 'pipelines.splitAndFilter("\t")'
# alias your javascript pipeline for easier use
pipemill alias splitAndFilter --single s --multi splitAndFilter
pipemill -s "\t"
#or
pipemill --splitAndFilter "\t"
# chain multiple aliased pipelines
# each pipeline shorthandle will also evaluate in order it was declared
pipemill -s -f "foo" -j# pipeline supports asynchronous code evaluation
pipemill -p 'setTimeout(function() { done("1 second");},1000)'As each pipe shares a sandbox environment on execution, its possible to set sandbox environment variables in one pipe and pass them onto the next.
# evaluate a file which connects to a database, then insert a document
pipemill -p "pipelines.runInContext('./example/connect.js')" \
-p 'var collection = connection.collection("documents");
quote> // Insert some documents
quote> collection.insertMany([
quote> {a : 1}, {a : 2}, {a : 3}
quote> ], function(err, result){
quote> if (err) throw new Error(err);
quote> console.log("Inserted 3 documents into the document collection");
quote> done();
quote> });'
Connected correctly to server
Inserted 3 documents into the document collectionCommands:
save [value]
remove [value]
list [value]
show [value]
alias [options] [value]
Options:
-h, --help output usage information
-p, --pipe [value] An expression to which will be evaluated in the context of the stream.
--encoding [value] Stdin encoding.
--buffer [value] Read stdin into process memory until stdin end is emitted, then process pipeline.
--debug [value] Turn on debug mode.
-f, --filter [value] filter pipeline command.
-j, --join [value] join pipeline command.
--fr [value] filterRecursive pipeline command.
-s, --split [value] split pipeline command.
--columnAt [value] columnAt pipeline command.
- Must be used with node 0.12.15 or GREATER.
