ID-56: read properties from stdin

Author: mlookaxw

CHANGELOG.adoc

@@ -7,6 +7,33 @@
 |https://github.com/Axway-API-Management-Plus/apigw-maven-plugin/issues/55[#55]
 |Enhancement
 |Add support for multiple base directories for certificates.
+
+|https://github.com/Axway-API-Management-Plus/apigw-maven-plugin/issues/56[#56]
+|Enhancement
+|Read properties from stdin.
+
+If the filename of the  `--prop` parameter is a single dash `-`, stdin will be used to read properties from a flat key/value JSON document.
+
+.Example of flat key/value JSON
+[source, json]
+----
+{
+  "prop1": "value1",
+  "prop2": "value2"
+}
+----
+
+[NOTE]
+====
+This feature can be used to read properties from external sources (e.g. AWS Secrets Manager or Hashicorp Vault).
+
+[source, shell]
+----
+# Get properties from Vault key/value engine
+vault kv get -format=json kv/apim \| jq .data.data \| buildfed --prop - -p src/gw.pol -e src/gw.env -c config/gw.config.json
+----
+====
+
 |===
 
 == Version 1.1.0

src/main/resources/scripts/lib/buildfed.py

@@ -88,7 +88,7 @@ def main():
             if not os.path.isfile(prop_file):
                 raise ValueError("File for command line property '%s' doesn't exist: %s" % (name, prop_file))
 
-            logging.debug("Reading command line property '%s' from file '%s'" % (name, prop_file))
+            logging.info("Reading command line property '%s' from file '%s'" % (name, prop_file))
             with codecs.open(prop_file, encoding='utf-8', mode='r') as pf:
                 cli_properties[name] = pf.read()
 

src/main/resources/scripts/lib/envconfig.py

@@ -2,6 +2,7 @@
 import os
 import logging
 import base64
+import sys
 
 from com.vordel.es.xes import PortableESPKFactory
 from java.text import SimpleDateFormat
@@ -24,23 +25,40 @@ def __init__(self, field_key, value):
 
 class PropConfig:
     def __init__(self, property_file_path_list):
+        stdin_loaded = False
         self.__properties = {}
         if not property_file_path_list:
             return
 
         for property_file_path in property_file_path_list:
-            if not os.path.exists(property_file_path):
-                raise ValueError("Property file '%s' doesn't exist!" % (property_file_path))
+            properties = None
+            if "-" == property_file_path:
+                if stdin_loaded:
+                    # properties already loaded from stdin
+                    continue
+                stdin_loaded = True
+                logging.info("Reading properties from stdin")
+                properties = json.load(sys.stdin)
+            else:
+                if not os.path.exists(property_file_path):
+                    raise ValueError("Property file '%s' doesn't exist!" % (property_file_path))
 
-            logging.info("Reading property file '%s'" % (property_file_path))
-            with open(property_file_path) as property_file:
-                properties_json = json.load(property_file)
+                logging.info("Reading property file '%s'" % (property_file_path))
+                with open(property_file_path) as property_file:
+                    properties_json = json.load(property_file)
 
-                if "properties" not in properties_json:
-                    raise ValueError("File '%s' is not a valid property file; missing 'properties' attribute!" % (property_file_path))
-                
-                for p in properties_json["properties"]:
-                    self.__properties[p] = properties_json["properties"][p]
+                    if "properties" not in properties_json:
+                        raise ValueError("File '%s' is not a valid property file; missing 'properties' attribute!" % (property_file_path))
+
+                    properties = properties_json["properties"]
+
+            # Add or overwrite properties
+            for p in properties:
+                if p not in self.__properties:
+                    logging.debug("set property '%s' from '%s'" % (p, property_file_path))
+                else:
+                    logging.debug("override property '%s' from '%s'" % (p, property_file_path))
+                self.__properties[p] = properties[p]
         return
 
     def get_property(self, key):

src/main/resources/scripts/lib/fedconfig.py

@@ -123,7 +123,7 @@ def __configure_entities(self):
     def __resolve_file_path(self, file):
         """Searches the certificate file within all specified base directories.
 
-        The first existing file wil be returned.
+        The first existing file will be returned.
         """
         if file and self.__base_dirs:
             for base_dir in self.__base_dirs: