ckvs_rpc.h

/**
 * @file ckvs_rpc.h
 * @brief client-side RPC using CURL
 * @author E Bugnion
 */

#pragma once
#include <curl/curl.h>

/**
 * @brief maximal size of the encrypted value.  hex-encoded is 2x
 */
#define CKVS_MAX_VALUE_LEN_HTTP_QUERY (14 * 32)

/**
 * @brief Holds the client state that represents a connection to a remote CKVS
 * server
 */
typedef struct ckvs_connection {
  CURL *curl;       /**< CURL instance used for the connection */
  const char *url;  /**< url to the remote server */
  char *resp_buf;   /**< buffer that will hold the response of the server */
  size_t resp_size; /**< size of resp_buf */
} ckvs_connection_t;

/**
 * @brief Initializes connection to the remote server at url.
 * @param conn (struct ckvs_connection*) the connection to initialize
 * @param url (const char*) target URL (string is not copied)
 * @return int, error code
 */
int ckvs_rpc_init(struct ckvs_connection *conn, const char *url);

/**
 * @brief Cleans up connection to remote server.
 * @param conn (struct ckvs_connection*) the connection to cleanup
 */
void ckvs_rpc_close(struct ckvs_connection *conn);

/* *************************************************** *
 * TODO WEEK 11                                        *
 * *************************************************** */
/**
 * @brief Sends an HTTP GET request to the connected server,
 * using the url and GET payload.
 *
 * @param conn (struct ckvs_connection*) the connection to the server
 * @param GET (const char*) the GET payload
 * @return int, error code
 */
int ckvs_rpc(struct ckvs_connection *conn, const char *GET);

/* *************************************************** *
 * TODO WEEK 13                                        *
 * *************************************************** */
/**
 * @brief Sends an HTTP POST request to the connected server,
 * using its url, and the GET and POST payloads.
 *
 * @param conn (struct ckvs_connection*) the connection to the server
 * @param GET (const char*) the GET payload. Should already contain the fields
 * "name" and "offset".
 * @param POST (const char*) the POST payload
 * @return int, error code
 */
int ckvs_post(struct ckvs_connection *conn, const char *GET, const char *POST);