Is there anything something like "http://www.example.com/jira/rest/agile/1.0/sprint?project=XYZ", to retrieve all the sprints in a project.
JIRA platform api can retrieve projects info and JIRA software API can retrieve sprints for a given board. But i need sprints for any given project (combination) or atleast boards for a given project so that i can retrieve sprints in those boards later
You can do it but with two resources:
https://docs.atlassian.com/jira-software/REST/cloud/#agile/1.0/board-getAllBoards
Use the query parameters projectKeyOrId and type to filter them.
Iterate all the elements and use the url below with the id of each board to get its sprints:
https://docs.atlassian.com/jira-software/REST/cloud/#agile/1.0/board/{boardId}/sprint-getAllSprints