X-Git-Url: https://git.tokkee.org/?p=sysdb.git;a=blobdiff_plain;f=src%2Finclude%2Fcore%2Fstore.h;h=94a571345852481b89479fd6664f2fc484c103b9;hp=a9788f44bb5b59ac7b166b46667bdb0acc9a70f1;hb=da52b4da948c741d20c7a3995ce5d133af377def;hpb=0e369b5129e64580e444e7d7ef4033a9d2995a28 diff --git a/src/include/core/store.h b/src/include/core/store.h index a9788f4..94a5713 100644 --- a/src/include/core/store.h +++ b/src/include/core/store.h @@ -32,8 +32,10 @@ #include "core/object.h" #include "core/data.h" #include "core/time.h" +#include "core/timeseries.h" #include "utils/strbuf.h" +#include #include #ifdef __cplusplus @@ -46,12 +48,47 @@ extern "C" { enum { SDB_HOST = 1, SDB_SERVICE, - SDB_ATTRIBUTE, + SDB_METRIC, + + SDB_ATTRIBUTE = 1 << 4, + + /* + * Queryable fields of a stored object. + */ + SDB_FIELD_NAME = 1 << 8, /* type: string */ + SDB_FIELD_LAST_UPDATE, /* type: datetime */ + SDB_FIELD_AGE, /* type: datetime */ + SDB_FIELD_INTERVAL, /* type: datetime */ + SDB_FIELD_BACKEND, /* type: array of strings */ + SDB_FIELD_VALUE, /* attributes only; type: type of the value */ }; #define SDB_STORE_TYPE_TO_NAME(t) \ (((t) == SDB_HOST) ? "host" \ : ((t) == SDB_SERVICE) ? "service" \ - : ((t) == SDB_ATTRIBUTE) ? "attribute" : "unknown") + : ((t) == SDB_METRIC) ? "metric" \ + : ((t) == SDB_ATTRIBUTE) ? "attribute" \ + : ((t) == (SDB_ATTRIBUTE | SDB_HOST)) ? "host attribute" \ + : ((t) == (SDB_ATTRIBUTE | SDB_SERVICE)) ? "service attribute" \ + : ((t) == (SDB_ATTRIBUTE | SDB_METRIC)) ? "metric attribute" \ + : "unknown") + +#define SDB_FIELD_TO_NAME(f) \ + (((f) == SDB_FIELD_NAME) ? "name" \ + : ((f) == SDB_FIELD_LAST_UPDATE) ? "last-update" \ + : ((f) == SDB_FIELD_AGE) ? "age" \ + : ((f) == SDB_FIELD_INTERVAL) ? "interval" \ + : ((f) == SDB_FIELD_BACKEND) ? "backend" \ + : ((f) == SDB_FIELD_VALUE) ? "value" \ + : "unknown") + +#define SDB_FIELD_TYPE(f) \ + (((f) == SDB_FIELD_NAME) ? SDB_TYPE_STRING \ + : ((f) == SDB_FIELD_LAST_UPDATE) ? SDB_TYPE_DATETIME \ + : ((f) == SDB_FIELD_AGE) ? SDB_TYPE_DATETIME \ + : ((f) == SDB_FIELD_INTERVAL) ? SDB_TYPE_DATETIME \ + : ((f) == SDB_FIELD_BACKEND) ? (SDB_TYPE_ARRAY | SDB_TYPE_STRING) \ + : ((f) == SDB_FIELD_VALUE) ? -1 /* unknown */ \ + : -1) /* * sdb_store_obj_t represents the super-class of any object stored in the @@ -62,20 +99,72 @@ struct sdb_store_obj; typedef struct sdb_store_obj sdb_store_obj_t; /* - * Queryable fields of a stored object. + * A metric store describes how to access a metric's data. */ -enum { - SDB_FIELD_LAST_UPDATE = 1, /* datetime */ - SDB_FIELD_AGE, /* datetime */ - SDB_FIELD_INTERVAL, /* datetime */ - SDB_FIELD_BACKEND, /* string */ -}; +typedef struct { + const char *type; + const char *id; +} sdb_metric_store_t; -#define SDB_FIELD_TO_NAME(f) \ - (((f) == SDB_FIELD_LAST_UPDATE) ? "last-update" \ - : ((f) == SDB_FIELD_AGE) ? "age" \ - : ((f) == SDB_FIELD_INTERVAL) ? "interval" \ - : ((f) == SDB_FIELD_BACKEND) ? "backend" : "unknown") +/* + * Expressions represent arithmetic expressions based on stored objects and + * their various attributes. + * + * An expression object inherits from sdb_object_t and, thus, may safely be + * cast to a generic object. + */ +struct sdb_store_expr; +typedef struct sdb_store_expr sdb_store_expr_t; +#define SDB_STORE_EXPR(obj) ((sdb_store_expr_t *)(obj)) + +/* + * An expression iterator iterates over the values of an iterable expression + * (see sdb_store_expr_iterable). + */ +struct sdb_store_expr_iter; +typedef struct sdb_store_expr_iter sdb_store_expr_iter_t; + +/* + * Store matchers may be used to lookup hosts from the store based on their + * various attributes. Service and attribute matchers are applied to a host's + * services and attributes and evaluate to true if *any* service or attribute + * matches. + * + * A store matcher object inherits from sdb_object_t and, thus, may safely be + * cast to a generic object. + */ +struct sdb_store_matcher; +typedef struct sdb_store_matcher sdb_store_matcher_t; +#define SDB_STORE_MATCHER(obj) ((sdb_store_matcher_t *)(obj)) + +/* + * A JSON formatter converts stored objects into the JSON format. + * See http://www.ietf.org/rfc/rfc4627.txt + */ +struct sdb_store_json_formatter; +typedef struct sdb_store_json_formatter sdb_store_json_formatter_t; + +/* + * A store writer describes the interface for plugins implementing a store. + */ +typedef struct { + int (*store_host)(const char *name, sdb_time_t last_update, + sdb_object_t *user_data); + int (*store_service)(const char *hostname, const char *name, + sdb_time_t last_update, sdb_object_t *user_data); + int (*store_metric)(const char *hostname, const char *name, + sdb_metric_store_t *store, sdb_time_t last_update, + sdb_object_t *user_data); + int (*store_attribute)(const char *hostname, + const char *key, const sdb_data_t *value, sdb_time_t last_update, + sdb_object_t *user_data); + int (*store_service_attr)(const char *hostname, const char *service, + const char *key, const sdb_data_t *value, sdb_time_t last_update, + sdb_object_t *user_data); + int (*store_metric_attr)(const char *hostname, const char *metric, + const char *key, const sdb_data_t *value, sdb_time_t last_update, + sdb_object_t *user_data); +} sdb_store_writer_t; /* * sdb_store_clear: @@ -109,7 +198,7 @@ sdb_store_host(const char *name, sdb_time_t last_update); * sdb_store_get_host increments the ref count of the host object. The caller * needs to deref it when no longer using it. */ -_Bool +bool sdb_store_has_host(const char *name); sdb_store_obj_t * @@ -142,8 +231,7 @@ sdb_store_attribute(const char *hostname, * specified 'service' object. If the referenced host does not exist, an error * will be reported. Else, a new entry will be created in the store. Any * memory required for storing the entry will be allocated an managed by the - * store itself. The specified service-object will not be referenced or - * further accessed. + * store itself. * * Returns: * - 0 on success @@ -174,14 +262,102 @@ sdb_store_service_attr(const char *hostname, const char *service, const char *key, const sdb_data_t *value, sdb_time_t last_update); /* - * Expressions specify arithmetic expressions. + * sdb_store_metric: + * Add/update a metric in the store. If the metric, identified by its name, + * already exists for the specified host, it will be updated according to the + * specified 'metric' object. If the referenced host does not exist, an error + * will be reported. Else, a new entry will be created in the store. Any + * memory required for storing the entry will be allocated an managed by the + * store itself. * - * A expression object inherits from sdb_object_t and, thus, may safely be - * cast to a generic object. + * If specified, the metric store describes where to access the metric's data. + * + * Returns: + * - 0 on success + * - a positive value if the new entry is older than the currently stored + * entry (in this case, no update will happen) + * - a negative value on error */ -struct sdb_store_expr; -typedef struct sdb_store_expr sdb_store_expr_t; -#define SDB_STORE_EXPR(obj) ((sdb_store_expr_t *)(obj)) +int +sdb_store_metric(const char *hostname, const char *name, + sdb_metric_store_t *store, sdb_time_t last_update); + +/* + * sdb_store_metric_attr: + * Add/update a metric's attribute in the store. If the attribute, identified + * by its key, already exists for the specified metric, it will be updated to + * the specified value. If the references metric (for the specified host) + * does not exist, an error will be reported. Any memory required for storing + * the entry will be allocated and managed by the store itself. + * + * Returns: + * - 0 on success + * - a positive value if the new entry is older than the currently stored + * entry (in this case, no update will happen) + * - a negative value on error + */ +int +sdb_store_metric_attr(const char *hostname, const char *metric, + const char *key, const sdb_data_t *value, sdb_time_t last_update); + +/* + * sdb_store_fetch_timeseries: + * Fetch the time-series described by the specified host's metric and + * serialize it as JSON into the provided string buffer. + * + * Returns: + * - 0 on success + * - a negative value else + */ +int +sdb_store_fetch_timeseries(const char *hostname, const char *metric, + sdb_timeseries_opts_t *opts, sdb_strbuf_t *buf); + +/* + * sdb_store_get_child: + * Retrieve a host's child object of the specified type and name. The + * reference count of the child object will be incremented before returning + * it. The caller is responsible for releasing the object once it's no longer + * used. + * + * Returns: + * - the child object on success + * - NULL else + */ +sdb_store_obj_t * +sdb_store_get_child(sdb_store_obj_t *host, int type, const char *name); + +/* + * sdb_store_get_field: + * Get the value of a stored object's queryable field. The caller is + * responsible for freeing any dynamically allocated memory possibly stored in + * the returned value. If 'res' is NULL, the function will return whether the + * field exists. + * + * Note: Retrieving the backend this way is not currently supported. + * + * Returns: + * - 0 on success + * - a negative value else + */ +int +sdb_store_get_field(sdb_store_obj_t *obj, int field, sdb_data_t *res); + +/* + * sdb_store_get_attr: + * Get the value of a stored object's attribute. The caller is responsible for + * freeing any dynamically allocated memory possibly stored in the returned + * value. If 'res' is NULL, the function will return whether the attribute + * exists. If specified, only attributes matching the filter will be + * considered. + * + * Returns: + * - 0 if the attribute exists + * - a negative value else + */ +int +sdb_store_get_attr(sdb_store_obj_t *obj, const char *name, sdb_data_t *res, + sdb_store_matcher_t *filter); /* * sdb_store_expr_create: @@ -195,6 +371,43 @@ typedef struct sdb_store_expr sdb_store_expr_t; sdb_store_expr_t * sdb_store_expr_create(int op, sdb_store_expr_t *left, sdb_store_expr_t *right); +/* + * sdb_store_expr_typed: + * Creates an expression which evaluates in the context of an object's sibling + * as specified by the given type. + * + * Returns: + * - an expression object on success + * - NULL else + */ +sdb_store_expr_t * +sdb_store_expr_typed(int typ, sdb_store_expr_t *expr); + +/* + * sdb_store_expr_fieldvalue: + * Creates an expression which evaluates to the value of the specified + * queryable field of a stored object. + * + * Returns: + * - an expression object on success + * - NULL else + */ +sdb_store_expr_t * +sdb_store_expr_fieldvalue(int field); + +/* + * sdb_store_expr_attrvalue: + * Creates an expression which evaluates to the value of the specified + * attribute of a stored object. Evaluates to a NULL value if the attribute + * does not exist. + * + * Returns: + * - an expression object on success + * - NULL else + */ +sdb_store_expr_t * +sdb_store_expr_attrvalue(const char *name); + /* * sdb_store_expr_constvalue: * Creates an expression which evaluates to the specified constant value. @@ -208,135 +421,158 @@ sdb_store_expr_constvalue(const sdb_data_t *value); /* * sdb_store_expr_eval: - * Evaluate an expression and stores the result in 'res'. The result's value - * will be allocated dynamically if necessary and, thus, should be free'd by - * the caller (e.g. using sdb_data_free_datum); + * Evaluate an expression for the specified stored object and stores the + * result in 'res'. The result's value will be allocated dynamically if + * necessary and, thus, should be free'd by the caller (e.g. using + * sdb_data_free_datum). The object may be NULL, in which case the expression + * needs to evaluate to a constant value. If specified, only objects matching + * the filter will be used during the evaluation. * * Returns: * - 0 on success * - a negative value else */ int -sdb_store_expr_eval(sdb_store_expr_t *expr, sdb_data_t *res); +sdb_store_expr_eval(sdb_store_expr_t *expr, sdb_store_obj_t *obj, + sdb_data_t *res, sdb_store_matcher_t *filter); + +/* + * sdb_store_expr_iterable: + * Check whether an expression, evaluated in the specified context (HOST, + * SERVICE, METRIC) is iterable, that is, if it may evaluate to multiple + * values. + */ +bool +sdb_store_expr_iterable(sdb_store_expr_t *expr, int context); /* - * Conditionals may be used to lookup hosts from the store based on a - * conditional expression. + * sdb_store_expr_iter: + * Iterate over the elements of an iterable expression. sdb_store_expr_iter + * returns NULL if the expression is not iterable (for the specified object). + * See also sdb_store_expr_iterable. * - * A conditional object inherits from sdb_object_t and, thus, may safely be - * cast to a generic object. + * sdb_store_expr_iter_get_next returns NULL if there is no next element. + */ +sdb_store_expr_iter_t * +sdb_store_expr_iter(sdb_store_expr_t *expr, sdb_store_obj_t *obj, + sdb_store_matcher_t *filter); +void +sdb_store_expr_iter_destroy(sdb_store_expr_iter_t *iter); + +bool +sdb_store_expr_iter_has_next(sdb_store_expr_iter_t *iter); +sdb_data_t +sdb_store_expr_iter_get_next(sdb_store_expr_iter_t *iter); + +/* + * sdb_store_dis_matcher: + * Creates a matcher matching the disjunction (logical OR) of two matchers. */ -struct sdb_store_cond; -typedef struct sdb_store_cond sdb_store_cond_t; -#define SDB_STORE_COND(obj) ((sdb_store_cond_t *)(obj)) +sdb_store_matcher_t * +sdb_store_dis_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right); /* - * sdb_store_attr_cond: - * Creates a conditional based on attribute values. The value of stored - * attributes is compared against the value the expression evaluates to. See - * sdb_data_cmp for details about the comparison. + * sdb_store_con_matcher: + * Creates a matcher matching the conjunction (logical AND) of two matchers. */ -sdb_store_cond_t * -sdb_store_attr_cond(const char *name, sdb_store_expr_t *expr); +sdb_store_matcher_t * +sdb_store_con_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right); /* - * sdb_store_obj_cond: - * Creates a conditional based on queryable object fields. The respective - * field of *any* object type is compared against the value the expression - * evaluates to. + * sdb_store_inv_matcher:: + * Creates a matcher matching the inverse (logical NOT) of a matcher. */ -sdb_store_cond_t * -sdb_store_obj_cond(int field, sdb_store_expr_t *expr); +sdb_store_matcher_t * +sdb_store_inv_matcher(sdb_store_matcher_t *m); /* - * Store matchers may be used to lookup hosts from the store based on their - * various attributes. Service and attribute matchers are applied to a host's - * services and attributes and evaluate to true if *any* service or attribute - * matches. - * - * A store matcher object inherits from sdb_object_t and, thus, may safely be - * cast to a generic object. + * sdb_store_any_matcher: + * Creates a matcher iterating over values of the first expression (which has + * to be iterable). It matches if *any* of those elements match 'm'. 'm' has + * to be an ary operation with the left operand unset. */ -struct sdb_store_matcher; -typedef struct sdb_store_matcher sdb_store_matcher_t; -#define SDB_STORE_MATCHER(obj) ((sdb_store_matcher_t *)(obj)) +sdb_store_matcher_t * +sdb_store_any_matcher(sdb_store_expr_t *iter, sdb_store_matcher_t *m); /* - * sdb_store_name_matcher: - * Creates a matcher matching by the specified object type's name. If 're' is - * true, the specified name is treated as a POSIX extended regular expression. - * Else, the exact name has to match (case-insensitive). + * sdb_store_all_matcher: + * Creates a matcher iterating over values of the first expression (which has + * to be iterable). It matches if *all* of those elements match 'm'. 'm' has + * to be an ary operation with the left operand unset. */ sdb_store_matcher_t * -sdb_store_name_matcher(int type, const char *name, _Bool re); +sdb_store_all_matcher(sdb_store_expr_t *iter, sdb_store_matcher_t *m); /* - * sdb_store_attr_matcher: - * Creates a matcher matching attributes based on their value. If 're' is - * true, the specified name is treated as a POSIX extended regular expression. - * Else, the exact name has to match (case-insensitive). + * sdb_store_in_matcher: + * Creates a matcher which matches if the right value evaluates to an array + * value and the left value is included in that array. See sdb_data_inarray + * for more details. */ sdb_store_matcher_t * -sdb_store_attr_matcher(const char *name, const char *value, _Bool re); +sdb_store_in_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); /* - * sdb_store_isnull_matcher: - * Creates a matcher matching "missing" attributes. + * sdb_store_nin_matcher: + * Like sdb_store_in_matcher but matches if the left value is not included in + * the right value. */ sdb_store_matcher_t * -sdb_store_isnull_matcher(const char *attr_name); +sdb_store_nin_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); /* * sdb_store_lt_matcher, sdb_store_le_matcher, sdb_store_eq_matcher, * sdb_store_ge_matcher, sdb_store_gt_matcher: - * Creates a matcher based on a conditional. The matcher matches objects for - * which the conditional evaluates the object to compare less than, less or - * equal, equal, greater or equal, or greater than the conditional's value - * repsectively. + * Create conditional matchers comparing the values of two expressions. The + * matcher matches if the left expression compres less than, less or equal + * than, equal to, not equal to, greater or equal than, or greater than the + * right expression. */ sdb_store_matcher_t * -sdb_store_lt_matcher(sdb_store_cond_t *cond); +sdb_store_lt_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); sdb_store_matcher_t * -sdb_store_le_matcher(sdb_store_cond_t *cond); +sdb_store_le_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); sdb_store_matcher_t * -sdb_store_eq_matcher(sdb_store_cond_t *cond); +sdb_store_eq_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); sdb_store_matcher_t * -sdb_store_ge_matcher(sdb_store_cond_t *cond); +sdb_store_ne_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); sdb_store_matcher_t * -sdb_store_gt_matcher(sdb_store_cond_t *cond); +sdb_store_ge_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); +sdb_store_matcher_t * +sdb_store_gt_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); /* - * sdb_store_matcher_parse_cmp: - * Parse a simple compare expression (. ). - * - * Returns: - * - a matcher object on success - * - NULL else + * sdb_store_regex_matcher: + * Creates a matcher which matches the string value the left expression + * evaluates to against the regular expression the right expression evaluates + * to. The right expression may either be a constant value regular expression + * or string or a dynamic value evaluating to a string. In the latter case, + * the string is compiled to a regex every time the matcher is executed. */ sdb_store_matcher_t * -sdb_store_matcher_parse_cmp(const char *obj_type, const char *attr, - const char *op, sdb_store_expr_t *expr); +sdb_store_regex_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); /* - * sdb_store_dis_matcher: - * Creates a matcher matching the disjunction (logical OR) of two matchers. + * sdb_store_nregex_matcher: + * Creates a regex matcher just like sdb_store_regex_matcher except that it + * matches in case the regular expression does not match. */ sdb_store_matcher_t * -sdb_store_dis_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right); +sdb_store_nregex_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right); /* - * sdb_store_con_matcher: - * Creates a matcher matching the conjunction (logical AND) of two matchers. + * sdb_store_isnull_matcher: + * Creates a matcher matching NULL values. */ sdb_store_matcher_t * -sdb_store_con_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right); +sdb_store_isnull_matcher(sdb_store_expr_t *expr); /* - * sdb_store_con_matcher:: - * Creates a matcher matching the inverse (logical NOT) of a matcher. + * sdb_store_isnnull_matcher: + * Creates a matcher matching non-NULL values. */ sdb_store_matcher_t * -sdb_store_inv_matcher(sdb_store_matcher_t *m); +sdb_store_isnnull_matcher(sdb_store_expr_t *expr); /* * sdb_store_matcher_matches: @@ -346,8 +582,8 @@ sdb_store_inv_matcher(sdb_store_matcher_t *m); * of the matcher. Only those objects matching the filter will be considered. * * Note that the filter is applied to all object types (hosts, service, - * attribute). Thus, any object-specific matchers are mostly unsuited for this - * purpose and, if used, may result in unexpected behavior. + * metric, attribute). Thus, any object-specific matchers are mostly unsuited + * for this purpose and, if used, may result in unexpected behavior. * * Returns: * - 1 if the object matches @@ -358,91 +594,141 @@ sdb_store_matcher_matches(sdb_store_matcher_t *m, sdb_store_obj_t *obj, sdb_store_matcher_t *filter); /* - * sdb_store_matcher_tostring: - * Format a matcher object as string. This is meant for logging or debugging - * purposes. + * sdb_store_matcher_op_cb: + * Callback constructing a matcher operator. */ -char * -sdb_store_matcher_tostring(sdb_store_matcher_t *m, char *buf, size_t buflen); +typedef sdb_store_matcher_t *(*sdb_store_matcher_op_cb) + (sdb_store_expr_t *, sdb_store_expr_t *); /* - * sdb_store_lookup_cb: - * Lookup callback. It is called for each matching object when looking up data - * in the store. The lookup aborts if the callback returns non-zero. + * sdb_store_parse_matcher_op: + * Parse a matcher operator and return a constructor for the respective + * matcher. + * + * Returns: + * - matcher operator constructor on success + * - NULL else */ -typedef int (*sdb_store_lookup_cb)(sdb_store_obj_t *obj, void *user_data); +sdb_store_matcher_op_cb +sdb_store_parse_matcher_op(const char *op); /* - * sdb_store_scan: - * Look up objects in the store. The specified callback function is called for - * each object in the store matching 'm'. The function performs a full scan of - * all hosts stored in the database. If specified, the filter will be used to - * preselect objects for further evaluation. See the description of - * 'sdb_store_matcher_matches' for details. + * sdb_store_parse_object_type: + * Parse the type name of a stored object. * * Returns: - * - 0 on success + * - the object type on success * - a negative value else */ int -sdb_store_scan(sdb_store_matcher_t *m, sdb_store_matcher_t *filter, - sdb_store_lookup_cb cb, void *user_data); +sdb_store_parse_object_type(const char *name); /* - * Flags for serialization functions. + * sdb_store_parse_object_type_plural: + * Parse the type name (plural) of a stored object. * - * By default, the full object will be included in the serialized output. When - * specifying any of the flags, the respective information will be left out. + * Returns: + * - the object type on success + * - a negative value else */ -enum { - SDB_SKIP_ATTRIBUTES = 1 << 0, - SDB_SKIP_SERVICES = 1 << 1, - SDB_SKIP_SERVICE_ATTRIBUTES = 1 << 2, - - SDB_SKIP_ALL = 0xffff, -}; +int +sdb_store_parse_object_type_plural(const char *name); /* - * sdb_store_tojson: - * Serialize the entire store to JSON and append the result to the specified - * buffer. + * sdb_store_parse_field_name: + * Parse the name of a stored object's queryable field. * * Returns: - * - 0 on success - * - a negative value on error + * - the field id on success + * - a negative value else */ int -sdb_store_tojson(sdb_strbuf_t *buf, int flags); +sdb_store_parse_field_name(const char *name); /* - * sdb_store_host_tojson: - * Serialize a host object to JSON and append the result to the specified - * buffer. + * sdb_store_lookup_cb: + * Lookup callback. It is called for each matching object when looking up data + * in the store passing on the lookup filter and the specified user-data. The + * lookup aborts early if the callback returns non-zero. + */ +typedef int (*sdb_store_lookup_cb)(sdb_store_obj_t *obj, + sdb_store_matcher_t *filter, void *user_data); + +/* + * sdb_store_scan: + * Look up objects of the specified type in the store. The specified callback + * function is called for each object in the store matching 'm'. The function + * performs a full scan of all objects stored in the database. If specified, + * the filter will be used to preselect objects for further evaluation. See + * the description of 'sdb_store_matcher_matches' for details. * * Returns: * - 0 on success - * - a negative value on error + * - a negative value else */ int -sdb_store_host_tojson(sdb_store_obj_t *host, sdb_strbuf_t *buf, int flags); +sdb_store_scan(int type, sdb_store_matcher_t *m, sdb_store_matcher_t *filter, + sdb_store_lookup_cb cb, void *user_data); + +/* + * Flags for JSON formatting. + */ +enum { + SDB_WANT_ARRAY = 1 << 0, +}; + +/* + * sdb_store_json_formatter: + * Create a JSON formatter for the specified object types writing to the + * specified buffer. + */ +sdb_store_json_formatter_t * +sdb_store_json_formatter(sdb_strbuf_t *buf, int type, int flags); /* - * sdb_store_iter_cb: - * Store iterator callback. Iteration stops if the callback returns non-zero. + * sdb_store_json_emit: + * Serialize a single object to JSON adding it to the string buffer associated + * with the formatter object. The serialized object will not include + * attributes or any child objects. Instead, call the function again for each + * of those objects. All attributes have to be emitted before any other + * children types. Use sdb_store_json_emit_full() to emit a full (filtered) + * object. + * + * Note that the output might not be valid JSON before calling + * sdb_store_json_finish(). + * + * Returns: + * - 0 on success + * - a negative value else */ -typedef int (*sdb_store_iter_cb)(sdb_store_obj_t *obj, void *user_data); +int +sdb_store_json_emit(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj); /* - * sdb_store_iterate: - * Iterate the entire store, calling the specified callback for each object. - * The user_data pointer is passed on to each call of the callback. + * sdb_store_json_emit_full: + * Serialize a single object including it's attributes and all children to + * JSON, adding it to the string buffer associated with the formatter object. + * The filter, if specified, is applied to each attribute and child object. + * Only matching objects will be included in the output. + * + * Note that the output might not be valid JSON before calling + * sdb_store_json_finish(). * * Returns: * - 0 on success * - a negative value else */ int -sdb_store_iterate(sdb_store_iter_cb cb, void *user_data); +sdb_store_json_emit_full(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj, + sdb_store_matcher_t *filter); + +/* + * sdb_store_json_finish: + * Finish the JSON output. This function has to be called once after emiting + * all objects. + */ +int +sdb_store_json_finish(sdb_store_json_formatter_t *f); #ifdef __cplusplus } /* extern "C" */