--- /dev/null
+#!/usr/bin/env python3
+# vi: et ts=4 sw=4 :
+
+#----------------------------------------------------------------------------------
+#
+# Copyright (c) 2021 AT&T Intellectual Property.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+#---------------------------------------------------------------------------------
+
+
+# Abstract: A config file (json) parser that looks for one or more "descriptions" and outputs
+# shell styled variable assignments that can be sourced by a script. Descriptions
+# are of the form:
+# <field>:[<field>:...:{*|shell_var_name}
+#
+# The description "xapp_name:*" will find the field xapp_name at the top level
+# and generate the variable assignment using the field name. The description
+# "xapp_name:xname" would find the same field but generate "xname=value" in the
+# output.
+#
+# It may be necssary to pull a field from an array of objects where a second field
+# in the object has a desired value. As an example, in the messaging section there
+# is an expected array of ports with each port having a name. To exctact a field
+# like this, the final field in the list may have the form:
+# <name>[]<match_name>=<desired-value>@<field-name>
+#
+# For "messaging:port[]name=rmr-data@port"
+# The messaging object is first located, and each element in the port array is examined.
+# when the element which contains the field "name:, with a value of "rmr-data",
+# the value of "port" is assigned to the output shell variable name.
+#
+# Limitations: This only allows one array to be traversed, and it is assumed to be the
+# last field. In other words, nested object arrays are not supported.
+#
+# Usage: j2src <config-file-name> <description> [<description>...]
+#
+# Date: 29 Janurary 2021
+# Author: E. Scott Daniels
+# ------------------------------------------------------------------------------------------------------
+import sys
+import json
+
+# Parse the description (see above) and return name and value to the caller. None,None is returned
+# when we have an error, or cannot find the field. Debug strings MUST start with # so that they don't
+# affect shell parsing of output.
+#
+def parse( pj, description, debug=False ) :
+ tokens = description.split( ":" ) # split fields, last is the output name or *
+ out_name = tokens[-1]
+ value = None
+
+ if len( tokens ) < 2 :
+ print( "## ERR ## badly formed description: %s" % description )
+ return None, None
+
+ for i in range( len( tokens ) - 1 ) :
+ atoks = tokens[i].split( "[]" )
+ if len( atoks ) > 1 : # array; [0] is the name, [1] is name=value@desired-name
+ if atoks[0] in pj :
+ nv = atoks[1].split( "=" )
+ name = nv[0]
+ sv = nv[1].split( "@" )
+ if len( sv ) < 2 :
+ if( debug ) :
+ print( "## ERR ## badly formed capture string: missing 'value<desired'" )
+ return None, None
+
+ match_val = sv[0]
+ pull_name = sv[1]
+ if out_name == "*" :
+ out_name = pull_name
+
+ ao = pj[atoks[0]] # directly at the array object
+ for i in range( len( ao ) ) : # run each element
+ if name in ao[i] :
+ if ao[i][name] == match_val : # this is the one we want
+ if pull_name in ao[i] :
+ return out_name, str( ao[i][pull_name] ) # all things go back as string
+
+ if debug :
+ print( "## WRN ## field is not in, or match value %s does NOT match, in %s[%d]: %s" % ( match_val, atoks[0], i, ao[i][name] ) )
+
+ return None, None # nothing matched and returned; bail now; array must be last field
+
+ else :
+ if debug :
+ print( "## WRN ## array %s is not found in %s" % (atoks[0], tokens[i]) )
+ return None, None
+ else :
+ if atoks[0] in pj :
+ pj = pj[atoks[0]] # if not last, this will be an object (we hope)
+ name = atoks[0]
+ value = pj # last one should just be a field to yank
+ else :
+ if debug :
+ print( "## WRN ## field not found: %s" % atoks[0] )
+ return None, None
+
+
+ if out_name == "*" :
+ return name, value
+ return out_name, value
+
+
+# take the name, value and print it as a valid shell variable. We convert True/False or true/false to
+# 1 and 0.
+#
+def print_svar( vname, value ) :
+ if value == "True" or value == "true" :
+ value = "1"
+ if value == "False" or value == "false" :
+ value = "0"
+ if not value.isnumeric() :
+ value = '"' + value + '"'
+
+ vname = vname.replace( " ", "_" ) # ensure it's a valid shell variable name
+ vname = vname.replace( "-", "_" )
+
+ print( "%s=%s" % ( vname, value ) )
+
+
+
+# --------------------------------------------------------------------------------------------------------------
+
+aidx = 1
+debug = False
+if sys.argv[1] == "debug" :
+ aidx += 1
+ debug = True
+
+f = open( sys.argv[aidx] )
+pj = json.load( f )
+f.close()
+aidx += 1
+
+for i in range( aidx, len( sys.argv ) ) :
+ name, val = parse( pj, sys.argv[i], debug )
+
+ if name != None and val != None :
+ print_svar( name, val )
Code Review / ric-app / mc.git / blobdiff