You can find an equivalent REST API your app for these requirements.
For example: getBlogPostByTitle can be translated to:
{{baseUrl}}/rest/api/content?type=blogpost&spaceKey={{spaceKey}}&title={{blogTitle}}&expand=version,space,history
You can find the REST API at DAC here: https://developer.atlassian.com/server/confluence/rest/
Please let me know if you have further questions.