Github user ottobackwards commented on a diff in the pull request:
https://github.com/apache/metron/pull/727#discussion_r138315694
--- Diff:
metron-stellar/stellar-common/src/main/java/org/apache/metron/stellar/dsl/functions/StringFunctions.java
---
@@ -550,4 +548,90 @@ else if(var.length() == 0) {
return new ParseException("Unable to parse JSON string");
}
}
+
+ @Stellar(name = "JSON_TO_MAP"
+ , description = "Returns a MAP object for the specified JSON
string"
+ , params = {
+ "str - the JSON String to convert, may be null"
+ }
+ , returns = "a MAP object containing the parsed JSON string"
+ )
+ public static class JsonToMap extends BaseStellarFunction {
+
+ @Override
+ public Object apply(List<Object> strings) {
+
+ if (strings == null || strings.size() == 0) {
+ throw new IllegalArgumentException("[JSON_TO_MAP] incorrect
arguments. Usage: JSON_TO_MAP <JSON String>");
+ }
+ String var = (strings.get(0) == null) ? null : (String)
strings.get(0);
+ if (var == null) {
+ return null;
+ } else if (var.length() == 0) {
+ return var;
+ } else {
+ ObjectMapper objectMapper = new ObjectMapper();
+
+ // First parse and check if input is valid JSON string
+ try {
+ objectMapper.readTree((String) strings.get(0));
+ } catch (JsonProcessingException ex) {
+ throw new ParseException("Valid JSON string not supplied", ex);
+ } catch (IOException e) {
+ e.printStackTrace();
+ }
+
+ // Return parsed JSON Object as a HashMap
+ try {
+ return (HashMap) JSONUtils.INSTANCE.load((String)
strings.get(0), Object.class);
+ } catch (IOException e) {
+ e.printStackTrace();
+ }
+ }
+ return new ParseException("Unable to parse JSON string");
+ }
+ }
+
+ @Stellar(name = "JSON_TO_LIST"
+ , description = "Returns a List object for the specified JSON
string"
+ , params = {
+ "str - the JSON String to convert, may be null"
+ }
+ , returns = "a List object containing the parsed JSON string"
+ )
+ public static class JsonToList extends BaseStellarFunction {
+
+ @Override
+ public Object apply(List<Object> strings) {
+
+ if (strings == null || strings.size() == 0) {
+ throw new IllegalArgumentException("[JSON_TO_LIST] incorrect
arguments. Usage: JSON_TO_LIST <JSON String>");
+ }
+ String var = (strings.get(0) == null) ? null : (String)
strings.get(0);
+ if (var == null) {
+ return null;
+ } else if (var.length() == 0) {
+ return var;
+ } else {
+ ObjectMapper objectMapper = new ObjectMapper();
+
+ // First parse and check if input is valid JSON string
+ try {
+ objectMapper.readTree((String) strings.get(0));
+ } catch (JsonProcessingException ex) {
+ throw new ParseException("Valid JSON string not supplied", ex);
+ } catch (IOException e) {
+ e.printStackTrace();
+ }
+
--- End diff --
I am not sure about using TypeReference here, Map<String,Object> is the
natural type, I think it would be List<Object> ?
What type of list do you get when you just cast?
---
