X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=blobdiff_plain;f=docs%2Freference-v3%2Ffunc-req.md;fp=docs%2Freference-v3%2Ffunc-req.md;h=bdec581f1f534cf66b4f777bc2817c096b47c13a;hb=525e9eaa644ca92fad23adfbb7c3119ae8b57a30;hp=0000000000000000000000000000000000000000;hpb=9e15212d26916f59fae2be6d9e618ae9b75a4f40;p=src%2Fapp-framework-binder.git diff --git a/docs/reference-v3/func-req.md b/docs/reference-v3/func-req.md new file mode 100644 index 00000000..bdec581f --- /dev/null +++ b/docs/reference-v3/func-req.md @@ -0,0 +1,835 @@ +Functions of class afb_req_t +============================ + +## General function + +### afb_req_is_valid + +```C +/** + * Checks whether the request 'req' is valid or not. + * + * @param req the request to check + * + * @return 0 if not valid or 1 if valid. + */ +int afb_req_is_valid( + afb_req_t*req); +``` + +### afb_req_get_api + +```C +/** + * Retrieves the api that serves the request + * + * @param req the request whose serving api is queried + * + * @return the api serving the request + */ +afb_api_t afb_req_get_api( + afb_req_t*req); +``` + +### afb_req_get_vcbdata + +```C +/** + * Retrieves the callback data of the verb. This callback data is set + * when the verb is created. + * + * @param req whose verb vcbdata is queried + * + * @return the callback data attached to the verb description + */ +void *afb_req_get_vcbdata( + afb_req_t*req); +``` + +### afb_req_get_called_api + +```C +/** + * Retrieve the name of the called api. + * + * @param req the request + * + * @return the name of the called api + * + * @see afb_api_new_api + * @see afb_api_add_alias + */ +const char *afb_req_get_called_api( + afb_req_t*req); +``` + +### afb_req_get_called_verb + +```C +/** + * Retrieve the name of the called verb + * + * @param req the request + * + * @return the name of the called verb + */ +const char *afb_req_get_called_verb( + afb_req_t*req); +``` + +### afb_req_addref + +```C +/** + * Increments the count of references of 'req'. + * + * @param req the request + * + * @return returns the request req + */ +afb_req_t*afb_req_addref( + afb_req_t*req); +``` + +### afb_req_unref + +```C +/** + * Decrement the count of references of 'req'. + * + * @param req the request + */ +void afb_req_unref( + afb_req_t*req); +``` + + +## Logging functions + +### afb_req_wants_log_level + +```C +/** + * Is the log message of 'level (as defined for syslog) required for the + * request 'req'? + * + * @param req the request + * @param level the level to check as defined for syslog: + * + * EMERGENCY 0 System is unusable + * ALERT 1 Action must be taken immediately + * CRITICAL 2 Critical conditions + * ERROR 3 Error conditions + * WARNING 4 Warning conditions + * NOTICE 5 Normal but significant condition + * INFO 6 Informational + * DEBUG 7 Debug-level messages + * + * @return 0 if not required or a value not null if required + * + * @see syslog + */ +int afb_req_wants_log_level( + afb_req_t*req, + int level); +``` + +### afb_req_vverbose + +```C +/** + * Send associated to 'req' a message described by 'fmt' and its 'args' + * to the journal for the verbosity 'level'. + * + * 'file', 'line' and 'func' are indicators of position of the code in source files + * (see macros __FILE__, __LINE__ and __func__). + * + * 'level' is defined by syslog standard: + * EMERGENCY 0 System is unusable + * ALERT 1 Action must be taken immediately + * CRITICAL 2 Critical conditions + * ERROR 3 Error conditions + * WARNING 4 Warning conditions + * NOTICE 5 Normal but significant condition + * INFO 6 Informational + * DEBUG 7 Debug-level messages + * + * @param req the request + * @param level the level of the message + * @param file the source filename that emits the message or NULL + * @param line the line number in the source filename that emits the message + * @param func the name of the function that emits the message or NULL + * @param fmt the message format as for printf + * @param args the arguments to the format + * + * @see printf + * @see afb_req_verbose + */ +void afb_req_vverbose( + afb_req_t*req, + int level, const char *file, + int line, + const char * func, + const char *fmt, + va_list args); +``` + +### afb_req_verbose + +```C +/** + * Send associated to 'req' a message described by 'fmt' and following parameters + * to the journal for the verbosity 'level'. + * + * 'file', 'line' and 'func' are indicators of position of the code in source files + * (see macros __FILE__, __LINE__ and __func__). + * + * 'level' is defined by syslog standard: + * EMERGENCY 0 System is unusable + * ALERT 1 Action must be taken immediately + * CRITICAL 2 Critical conditions + * ERROR 3 Error conditions + * WARNING 4 Warning conditions + * NOTICE 5 Normal but significant condition + * INFO 6 Informational + * DEBUG 7 Debug-level messages + * + * @param req the request + * @param level the level of the message + * @param file the source filename that emits the message or NULL + * @param line the line number in the source filename that emits the message + * @param func the name of the function that emits the message or NULL + * @param fmt the message format as for printf + * @param ... the arguments of the format 'fmt' + * + * @see printf + */ +void afb_req_verbose( + afb_req_t*req, + int level, const char *file, + int line, + const char * func, + const char *fmt, + ...); +``` + +## Arguments/parameters function + +### afb_req_get + +```C +/** + * Gets from the request 'req' the argument of 'name'. + * + * Returns a PLAIN structure of type 'struct afb_arg'. + * + * When the argument of 'name' is not found, all fields of result are set to NULL. + * + * When the argument of 'name' is found, the fields are filled, + * in particular, the field 'result.name' is set to 'name'. + * + * There is a special name value: the empty string. + * The argument of name "" is defined only if the request was made using + * an HTTP POST of Content-Type "application/json". In that case, the + * argument of name "" receives the value of the body of the HTTP request. + * + * @param req the request + * @param name the name of the argument to get + * + * @return a structure describing the retrieved argument for the request + * + * @see afb_req_value + * @see afb_req_path + */ +struct afb_arg afb_req_get( + afb_req_t*req, + const char *name); +``` + +### afb_req_value + +```C +/** + * Gets from the request 'req' the string value of the argument of 'name'. + * Returns NULL if when there is no argument of 'name'. + * Returns the value of the argument of 'name' otherwise. + * + * Shortcut for: afb_req_get(req, name).value + * + * @param req the request + * @param name the name of the argument's value to get + * + * @return the value as a string or NULL + * + * @see afb_req_get + * @see afb_req_path + */ +const char *afb_req_value( + afb_req_t*req, + const char *name); +``` + +### afb_req_path + +```C +/** + * Gets from the request 'req' the path for file attached to the argument of 'name'. + * Returns NULL if when there is no argument of 'name' or when there is no file. + * Returns the path of the argument of 'name' otherwise. + * + * Shortcut for: afb_req_get(req, name).path + * + * @param req the request + * @param name the name of the argument's path to get + * + * @return the path if any or NULL + * + * @see afb_req_get + * @see afb_req_value + */ +const char *afb_req_path( + afb_req_t*req, + const char *name); +``` + +### afb_req_json + +```C +/** + * Gets from the request 'req' the json object hashing the arguments. + * + * The returned object must not be released using 'json_object_put'. + * + * @param req the request + * + * @return the JSON object of the query + * + * @see afb_req_get + * @see afb_req_value + * @see afb_req_path + */ +struct json_object *afb_req_json( + afb_req_t*req); +``` + +## Reply functions + +The functions **success** and **fail** are still supported. +These functions are now implemented as the following macros: + +```C +#define afb_req_success(r,o,i) afb_req_reply(r,o,NULL,i) +#define afb_req_success_f(r,o,...) afb_req_reply_f(r,o,NULL,__VA_ARGS__) +#define afb_req_success_v(r,o,f,v) afb_req_reply_v(r,o,NULL,f,v) +#define afb_req_fail(r,e,i) afb_req_reply(r,NULL,e,i) +#define afb_req_fail_f(r,e,...) afb_req_reply_f(r,NULL,e,__VA_ARGS__) +#define afb_req_fail_v(r,e,f,v) afb_req_reply_v(r,NULL,e,f,v) +``` + + +### afb_req_reply + +```C +/** + * Sends a reply to the request 'req'. + * + * The status of the reply is set to 'error' (that must be NULL on success). + * Its send the object 'obj' (can be NULL) with an + * informational comment 'info (can also be NULL). + * + * For convenience, the function calls 'json_object_put' for 'obj'. + * Thus, in the case where 'obj' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * @param req the request + * @param obj the replied object or NULL + * @param error the error message if it is a reply error or NULL + * @param info an informative text or NULL + * + * @see afb_req_reply_v + * @see afb_req_reply_f + */ +void afb_req_reply( + afb_req_t*req, + struct json_object *obj, + const char *error, + const char *info); +``` + +### afb_req_reply_v + +```C +/** + * Same as 'afb_req_reply_f' but the arguments to the format 'info' + * are given as a variable argument list instance. + * + * For convenience, the function calls 'json_object_put' for 'obj'. + * Thus, in the case where 'obj' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * @param req the request + * @param obj the replied object or NULL + * @param error the error message if it is a reply error or NULL + * @param info an informative text containing a format as for vprintf + * @param args the va_list of arguments to the format as for vprintf + * + * @see afb_req_reply + * @see afb_req_reply_f + * @see vprintf + */ +void afb_req_reply_v( + afb_req_t*req, + struct json_object *obj, + const char *error, + const char *info, + va_list args); +``` + +### afb_req_reply_f + +```C +/** + * Same as 'afb_req_reply' but the 'info' is a formatting + * string followed by arguments. + * + * For convenience, the function calls 'json_object_put' for 'obj'. + * Thus, in the case where 'obj' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * @param req the request + * @param obj the replied object or NULL + * @param error the error message if it is a reply error or NULL + * @param info an informative text containing a format as for printf + * @param ... the arguments to the format as for printf + * + * @see afb_req_reply + * @see afb_req_reply_v + * @see printf + */ +void afb_req_reply_f( + afb_req_t*req, + struct json_object *obj, + const char *error, + const char *info, + ...); +``` + +## Subcall functions + + + +### afb_req_subcall + +```C +/** + * Calls the 'verb' of the 'api' with the arguments 'args' and 'verb' in the name of the binding. + * The result of the call is delivered to the 'callback' function with the 'callback_closure'. + * + * For convenience, the function calls 'json_object_put' for 'args'. + * Thus, in the case where 'args' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * The 'callback' receives 5 arguments: + * 1. 'closure' the user defined closure pointer 'closure', + * 2. 'object' a JSON object returned (can be NULL) + * 3. 'error' a string not NULL in case of error + * 4. 'info' a string handling some info (can be NULL) + * 5. 'req' the req + * + * @param req The request + * @param api The api name of the method to call + * @param verb The verb name of the method to call + * @param args The arguments to pass to the method + * @param flags The bit field of flags for the subcall as defined by @ref afb_req_subcall_flags_t + * @param callback The to call on completion + * @param closure The closure to pass to the callback + * + * The flags are any combination of the following values: + * + * - afb_req_x2_subcall_catch_events = 1 + * + * the calling API wants to receive the events from subscription + * + * - afb_req_x2_subcall_pass_events = 2 + * + * the original request will receive the events from subscription + * + * - afb_req_x2_subcall_on_behalf = 4 + * + * the calling API wants to use the credentials of the original request + * + * - afb_req_x2_subcall_api_session = 8 + * + * the calling API wants to use its session instead of the one of the + * original request + * + * @see also 'afb_req_subcall_sync' + */ +void afb_req_subcall( + afb_req_t*req, + const char *api, + const char *verb, + struct json_object *args, + int flags, + void (*callback)( + void *closure, + struct json_object *object, + const char *error, + const char * info, + afb_req_t*req), + void *closure); +``` + +### afb_req_subcall_sync + +```C +/** + * Makes a call to the method of name 'api' / 'verb' with the object 'args'. + * This call is made in the context of the request 'req'. + * This call is synchronous, it waits untill completion of the request. + * It returns 0 on success or a negative value on error answer. + * + * For convenience, the function calls 'json_object_put' for 'args'. + * Thus, in the case where 'args' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * See also: + * - 'afb_req_subcall_req' that is convenient to keep request alive automatically. + * - 'afb_req_subcall' that doesn't keep request alive automatically. + * + * @param req The request + * @param api The api name of the method to call + * @param verb The verb name of the method to call + * @param args The arguments to pass to the method + * @param flags The bit field of flags for the subcall as defined by @ref afb_req_subcall_flags + * @param object a pointer where the replied JSON object is stored must be freed using @ref json_object_put (can be NULL) + * @param error a pointer where a copy of the replied error is stored must be freed using @ref free (can be NULL) + * @param info a pointer where a copy of the replied info is stored must be freed using @ref free (can be NULL) + * + * @return 0 in case of success or -1 in case of error + */ +int afb_req_subcall_sync( + afb_req_t*req, + const char *api, + const char *verb, + struct json_object *args, + int flags, + struct json_object **object, + char **error, + char **info); +``` + +## Event functions + +### afb_req_subscribe + +```C +/** + * Establishes for the client link identified by 'req' a subscription + * to the 'event'. + * + * @param req the request + * @param event the event to subscribe + * + * @return 0 in case of successful subscription or -1 in case of error. + */ +int afb_req_subscribe( + afb_req_t*req, + afb_event_t event); +``` + +### afb_req_unsubscribe + +```C +/** + * Revokes the subscription established to the 'event' for the client + * link identified by 'req'. + * Returns 0 in case of successful subscription or -1 in case of error. + * + * @param req the request + * @param event the event to revoke + * + * @return 0 in case of successful subscription or -1 in case of error. + */ +int afb_req_unsubscribe( + afb_req_t*req, + afb_event_t event); +``` + +## Session functions + +### afb_req_context + +```C +/** + * Manage the pointer stored by the binding for the client session of 'req'. + * + * If no previous pointer is stored or if 'replace' is not zero, a new value + * is generated using the function 'create_context' called with the 'closure'. + * If 'create_context' is NULL the generated value is 'closure'. + * + * When a value is created, the function 'free_context' is recorded and will + * be called (with the created value as argument) to free the created value when + * it is not more used. + * + * This function is atomic: it ensures that 2 threads will not race together. + * + * @param req the request + * @param replace if not zero an existing value is replaced + * @param create_context the creation function or NULL + * @param free_context the destroying function or NULL + * @param closure the closure to the creation function + * + * @return the stored value + */ +void *afb_req_context( + afb_req_t*req, + int replace, + void *(*create_context)(void *closure), + void (*free_context)(void*), + void *closure); +``` + +### afb_req_context_get + +```C +/** + * Gets the pointer stored by the binding for the session of 'req'. + * When the binding has not yet recorded a pointer, NULL is returned. + * + * Shortcut for: afb_req_context(req, 0, NULL, NULL, NULL) + * + * @param req the request + * + * @return the previously stored value + */ +void *afb_req_context_get( + afb_req_t*req); +``` + +### afb_req_context_set + +```C +/** + * Stores for the binding the pointer 'context' to the session of 'req'. + * The function 'free_context' will be called when the session is closed + * or if binding stores an other pointer. + * + * Shortcut for: afb_req_context(req, 1, NULL, free_context, context) + * + * + * @param req the request + * @param context the context value to store + * @param free_context the cleaning function for the stored context (can be NULL) + */ +void afb_req_context_set( + afb_req_t*req, + void *context, + void (*free_context)(void*)); +``` + +### afb_req_context_clear + +```C +/** + * Frees the pointer stored by the binding for the session of 'req' + * and sets it to NULL. + * + * Shortcut for: afb_req_context_set(req, NULL, NULL) + * + * @param req the request + */ +void afb_req_context_clear( + afb_req_t*req); +``` + +### afb_req_session_close + +```C +/** + * Closes the session associated with 'req' + * and delete all associated contexts. + * + * @param req the request + */ +void afb_req_session_close( + afb_req_t*req); +``` + +### afb_req_session_set_LOA + +```C +/** + * Sets the level of assurance of the session of 'req' + * to 'level'. The effect of this function is subject of + * security policies. + * + * @param req the request + * @param level of assurance from 0 to 7 + * + * @return 0 on success or -1 if failed. + */ +int afb_req_session_set_LOA( + afb_req_t*req, + unsigned level); +``` + +## Credential/client functions + +### afb_req_has_permission + +```C +/** + * Check whether the 'permission' is granted or not to the client + * identified by 'req'. + * + * @param req the request + * @param permission string to check + * + * @return 1 if the permission is granted or 0 otherwise. + */ +int afb_req_has_permission( + afb_req_t*req, + const char *permission); +``` + +### afb_req_get_application_id + +```C +/** + * Get the application identifier of the client application for the + * request 'req'. + * + * Returns the application identifier or NULL when the application + * can not be identified. + * + * The returned value if not NULL must be freed by the caller + * + * @param req the request + * + * @return the string for the application id of the client MUST BE FREED + */ +char *afb_req_get_application_id( + afb_req_t*req); +``` + +### afb_req_get_uid + +```C +/** + * Get the user identifier (UID) of the client for the + * request 'req'. + * + * @param req the request + * + * @return -1 when the application can not be identified or the unix uid. + * + */ +int afb_req_get_uid( + afb_req_t*req); +``` + +### afb_req_get_client_info + +```C +/** + * Get informations about the client of the + * request 'req'. + * + * Returns an object with client informations: + * { + * "pid": int, "uid": int, "gid": int, + * "label": string, "id": string, "user": string, + * "uuid": string, "LOA": int + * } + * + * If some of this information can't be computed, the field of the return + * object will not be set at all. + * + * @param req the request + * + * @return a JSON object that must be freed using @ref json_object_put + */ +struct json_object *afb_req_get_client_info( + afb_req_t*req); +``` + +## Legacy functions + +### afb_req_subcall_legacy + +```C +/** + * @deprecated use @ref afb_req_subcall + * + * Makes a call to the method of name 'api' / 'verb' with the object 'args'. + * This call is made in the context of the request 'req'. + * On completion, the function 'callback' is invoked with the + * 'closure' given at call and two other parameters: 'iserror' and 'result'. + * 'status' is 0 on success or negative when on an error reply. + * 'result' is the json object of the reply, you must not call json_object_put + * on the result. + * + * For convenience, the function calls 'json_object_put' for 'args'. + * Thus, in the case where 'args' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * @param req the request + * @param api the name of the api to call + * @param verb the name of the verb to call + * @param args the arguments of the call as a JSON object + * @param callback the call back that will receive the reply + * @param closure the closure passed back to the callback + * + * @see afb_req_subcall + * @see afb_req_subcall_sync + */ +void afb_req_subcall_legacy( + afb_req_t*req, + const char *api, + const char *verb, + struct json_object *args, + void (*callback)( + void *closure, + int iserror, + struct json_object *result, + afb_req_t*req), + void *closure); +``` + +### afb_req_subcall_sync_legacy + +```C +/** + * @deprecated use @ref afb_req_subcall_sync + * + * Makes a call to the method of name 'api' / 'verb' with the object 'args'. + * This call is made in the context of the request 'req'. + * This call is synchronous, it waits untill completion of the request. + * It returns 0 on success or a negative value on error answer. + * The object pointed by 'result' is filled and must be released by the caller + * after its use by calling 'json_object_put'. + * + * For convenience, the function calls 'json_object_put' for 'args'. + * Thus, in the case where 'args' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * @param req the request + * @param api the name of the api to call + * @param verb the name of the verb to call + * @param args the arguments of the call as a JSON object + * @param result the pointer to the JSON object pointer that will receive the result + * + * @return 0 on success or a negative value on error answer. + * + * @see afb_req_subcall + * @see afb_req_subcall_sync + */ +int afb_req_subcall_sync_legacy( + afb_req_t*req, + const char *api, + const char *verb, + struct json_object *args, + struct json_object **result); +``` +