go-link-shortener-backend, v1.5

Back-end of the service for shorting links.

Formatting a counter as an integer number in the 62 base when generating link codes.

generating link codes:
- formatting a counter as an integer number in the 62 base.

RESTful API:
- link model:
  - creating by an URL;
  - getting by a code;
- representing in a JSON:
  - payloads:
    - of requests;
    - of responses;
  - errors;
generating link codes:
- using a version 4 UUID;
- using sequential counters:
  - formatting:
    - formatting a counter as an integer number in the 10 base;
    - formatting a counter as an integer number in the 62 base;
  - storing:
    - storing in a database only counters chunks;
    - storing counters themselves in memory;
  - sharding:
    - sharding counters chunks;
    - selecting a shard of a counter chunk at random;
server:
- additional routing:
  - redirecting to the link URL by its code;
  - serving static files;
- storing settings in environment variables;
- supporting graceful shutdown;
- logging:
  - logging requests;
  - logging errors;
- panics:
  - recovering on panics;
  - logging of panics;
databases:
- storing links in the MongoDB database;
- storing counters chunks in the etcd database:
  - using a record version as a counter chunk;
- caching links in the Redis database;
distributing:
- Docker image;
- Docker Compose configuration.

Content: code.

License: MIT.