当您在脚本快照中选择Python时,它实际上意味着Jython。因此,您基本上可以在脚本中导入 Java 类。
以下是我在其中一个节点的/tmp文件夹中编写虚拟文件的实现。
# Import the interface required by the Script snap.
from com.snaplogic.scripting.language import ScriptHook
import java.util
import com.fasterxml.jackson.databind
import java.io
class TransformScript(ScriptHook):
def __init__(self, input, output, error, log):
self.input = input
self.output = output
self.error = error
self.log = log
# The "execute()" method is called once when the pipeline is started
# and allowed to process its inputs or just send data to its outputs.
def execute(self):
self.log.info("Executing Transform script")
while self.input.hasNext():
try:
# Read the next document, wrap it in a map and write out the wrapper
in_doc = self.input.next()
wrapper = java.util.HashMap()
om = com.fasterxml.jackson.databind.ObjectMapper()
target_file = java.io.File("/tmp/" + in_doc['filename'])
om.writeValue(target_file, in_doc['content']);
wrapper['original'] = in_doc
wrapper['status'] = "success"
self.output.write(in_doc, wrapper)
except Exception as e:
errWrapper = {
'errMsg' : str(e.args)
}
self.log.error("Error in python script")
self.error.write(errWrapper)
self.log.info("Finished executing the Transform script")
# The Script Snap will look for a ScriptHook object in the "hook"
# variable. The snap will then call the hook's "execute" method.
hook = TransformScript(input, output, error, log)
以下是脚本快照的输入 JSON。
[{"filename":"write_test.txt","content":{"id":123,"message":"xyz","valid":true}}]
检查节点中的文件。
$ cd /tmp
$ cat write_test.txt
[{"filename":"write_test.txt","content":{"id":123,"message":"xyz","valid":true}}]
注意:我使用 Jackson 的 ObjectMapper,因为我主要处理 JSON。