פיתוח מעטפת REST ב-JAVA סביב תוצאות של db query, לשילוב ב-WAR קיים

The goal is to implement a REST API servlet that receives a few parameters (details below), uses them to extract the right results from a database query, and then package the results as a JSON object to return to the client.

The required functionality is to create a Java servlet with a function that receives a REST request (HttpServletRequest), extracts the parameters, gets the data and prepares the JSON object to return.
Another Java class is used for data access – the call to the stored procedure should be in a separate class.

Request
• Source server (string)
• Target server (string)
• Port (number)
• Metric (enum)
o Client reset count
o Server reset count
o Request byte count
o Response byte count
o Request packet count
o Response packet count
• Start time (timestamp)
• End time (timestamp) – must be later than ‘start time’ by at least 10 minutes – i.e. queries for time periods shorter than 10 minutes will not be allowed.
• Section length in minutes (integer) – the section length should be limited according to the full time period of the query. Need to divide the time period by the section length to find the number of sections, then check
o Number of sections higher than some maximum value (40 by default, configurable) will not be allowed
o Number of sections smaller than 5 will not be allowed.
o If the number of sections exceeds the allowed number, then the section length is adjusted accordingly.

Response (JSON)
• In case of error:
o {"code":<error code - integer> ,"message”: <string>, "detailedErrorMessage”: <string> ,"payload":<string>}
• In case of success:
• {“metricName”: <string>, “maxValue”:<integer>, ”minValue”:<integer>, ”avgValue”:<integer>, “sum”:<integer>, “numSections”:<int>,”sectionLength”:<section>,“sections”:<sectionsArray>}
• sectionsArray:
[
{“startTime”:<datetime>, “maxValue”: ”:<integer>, ”minValue”:<integer>, ”avgValue”:<integer>, “sum”:<integer>}
{…}
{…}
]