This is a simple JSON Server that delivers pseudo performance data. It is used to help testing programming capabilities
1) Requirements for the program that should be developed using JAVA
The program shall retrieve for a given 5 minute slice the performance data from the server. The unix timestamp shall be the timestamp at the beginning of the time interval. If the start time of the program is smaller than current time - 5 minutes another time slice shall be retrieved. After successfully retrieving a time slice the start date of the time slice shall be written to a file on the disk. If no more time slices can be retrieved the program shall terminate.
If the program is started again the file shall be read and retrieving of data shall start with the next time slice. The date/time in the file shall be in a human understandable format.
The output shall be one or more valid JSON files with the following format. (Each time slice is one JSON file.)
- each line is a valid JSON format
- {starttime:"|ISO 8601 Format|",duration:|duration in minutes|,key:{key:"|Value of Key|"},value:{|Name-Val1|:|val1|,|Name-Val2|:|val2|,...}}
Hint: One of easiest JSON formating libraries is Google GSON: https://github.com/google/gson
2) The Simulator
The first thing is a simulator, that simulates providing performance data.
It can be started with java -jar perfserver-[....].jar. The source code is in this github repository. This launches a webserver with the folliwng functions on http://127.0.0.1:8001
/hello -> This answers with: Hello World /getdata -> This shall be called with the following parameter ?time=[unix timestamp in seconds]
http://127.0.0.1:8001/getdata?time=1639062504
This delivers a CSV file in the following format:
Timestamp|Duration|Key|[Name of values|]*