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README.md

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 # gojsonvalidator
 Generic tool to validate input json string and check the parameters
+
+## Introduce
+In most of the micro-service application, we use json to deliver data from one to another, but validating the parameter in json is always boring, so this tool will give you a big help. It can check which parameters are required, and if the value are exceed the limitation, or you can set a default value if some optional key is not given.
+
+## How to Use