Support local managment for embedded agent on nginx

external/yq/pkg/yqlib/doc/usage/properties.md

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+# Properties
+
+Encode/Decode/Roundtrip to/from a property file. Line comments on value nodes will be copied across.
+
+By default, empty maps and arrays are not encoded - see below for an example on how to encode a value for these.
+
+## Encode properties
+Note that empty arrays and maps are not encoded by default.
+
+Given a sample.yml file of:
+```yaml
+# block comments come through
+person: # neither do comments on maps
+    name: Mike Wazowski # comments on values appear
+    pets: 
+    - cat # comments on array values appear
+    food: [pizza] # comments on arrays do not
+emptyArray: []
+emptyMap: []
+
+```
+then
+```bash
+yq -o=props sample.yml
+```
+will output
+```properties
+# block comments come through
+# comments on values appear
+person.name = Mike Wazowski
+
+# comments on array values appear
+person.pets.0 = cat
+person.food.0 = pizza
+```
+
+## Encode properties: scalar encapsulation
+Note that string values with blank characters in them are encapsulated with double quotes
+
+Given a sample.yml file of:
+```yaml
+# block comments come through
+person: # neither do comments on maps
+    name: Mike Wazowski # comments on values appear
+    pets: 
+    - cat # comments on array values appear
+    food: [pizza] # comments on arrays do not
+emptyArray: []
+emptyMap: []
+
+```
+then
+```bash
+yq -o=props --unwrapScalar=false sample.yml
+```
+will output
+```properties
+# block comments come through
+# comments on values appear
+person.name = "Mike Wazowski"
+
+# comments on array values appear
+person.pets.0 = cat
+person.food.0 = pizza
+```
+
+## Encode properties: no comments
+Given a sample.yml file of:
+```yaml
+# block comments come through
+person: # neither do comments on maps
+    name: Mike Wazowski # comments on values appear
+    pets: 
+    - cat # comments on array values appear
+    food: [pizza] # comments on arrays do not
+emptyArray: []
+emptyMap: []
+
+```
+then
+```bash
+yq -o=props '... comments = ""' sample.yml
+```
+will output
+```properties
+person.name = Mike Wazowski
+person.pets.0 = cat
+person.food.0 = pizza
+```
+
+## Encode properties: include empty maps and arrays
+Use a yq expression to set the empty maps and sequences to your desired value.
+
+Given a sample.yml file of:
+```yaml
+# block comments come through
+person: # neither do comments on maps
+    name: Mike Wazowski # comments on values appear
+    pets: 
+    - cat # comments on array values appear
+    food: [pizza] # comments on arrays do not
+emptyArray: []
+emptyMap: []
+
+```
+then
+```bash
+yq -o=props '(.. | select( (tag == "!!map" or tag =="!!seq") and length == 0)) = ""' sample.yml
+```
+will output
+```properties
+# block comments come through
+# comments on values appear
+person.name = Mike Wazowski
+
+# comments on array values appear
+person.pets.0 = cat
+person.food.0 = pizza
+emptyArray = 
+emptyMap = 
+```
+
+## Decode properties
+Given a sample.properties file of:
+```properties
+# block comments come through
+# comments on values appear
+person.name = Mike Wazowski
+
+# comments on array values appear
+person.pets.0 = cat
+person.food.0 = pizza
+
+```
+then
+```bash
+yq -p=props sample.properties
+```
+will output
+```yaml
+person:
+    # block comments come through
+    # comments on values appear
+    name: Mike Wazowski
+    pets:
+        # comments on array values appear
+        - cat
+    food:
+        - pizza
+```
+
+## Decode properties - array should be a map
+If you have a numeric map key in your property files, use array_to_map to convert them to maps.
+
+Given a sample.properties file of:
+```properties
+things.10 = mike
+```
+then
+```bash
+yq -p=props '.things |= array_to_map' sample.properties
+```
+will output
+```yaml
+things:
+    10: mike
+```
+
+## Roundtrip
+Given a sample.properties file of:
+```properties
+# block comments come through
+# comments on values appear
+person.name = Mike Wazowski
+
+# comments on array values appear
+person.pets.0 = cat
+person.food.0 = pizza
+
+```
+then
+```bash
+yq -p=props -o=props '.person.pets.0 = "dog"' sample.properties
+```
+will output
+```properties
+# block comments come through
+# comments on values appear
+person.name = Mike Wazowski
+
+# comments on array values appear
+person.pets.0 = dog
+person.food.0 = pizza
+```
+