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index bc4de1090f6d4a95e980835cf7c4033002776e79..2624194955c3ed9ebee454fec4e83dc017e0c8ec 100644 (file)
--- a/src/include/core/store.h
+++ b/src/include/core/store.h
#include "sysdb.h"
#include "core/object.h"
+#include "core/data.h"
#include "core/time.h"
-#include "utils/llist.h"
+#include "core/timeseries.h"
#include "utils/strbuf.h"
#include <stdio.h>
extern "C" {
#endif
+/*
+ * Store object types.
+ */
+enum {
+ SDB_HOST = 1,
+ SDB_SERVICE,
+ SDB_METRIC,
+ SDB_ATTRIBUTE,
+};
+#define SDB_STORE_TYPE_TO_NAME(t) \
+ (((t) == SDB_HOST) ? "host" \
+ : ((t) == SDB_SERVICE) ? "service" \
+ : ((t) == SDB_METRIC) ? "metric" \
+ : ((t) == SDB_ATTRIBUTE) ? "attribute" : "unknown")
+
+/*
+ * sdb_store_obj_t represents the super-class of any object stored in the
+ * database. It inherits from sdb_object_t and may safely be cast to a generic
+ * object to access its name.
+ */
+struct sdb_store_obj;
+typedef struct sdb_store_obj sdb_store_obj_t;
+
+/*
+ * 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))
+
+/*
+ * 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))
+
+/*
+ * Queryable fields of a stored object.
+ */
+enum {
+ SDB_FIELD_NAME = 1, /* string */
+ SDB_FIELD_LAST_UPDATE, /* datetime */
+ SDB_FIELD_AGE, /* datetime */
+ SDB_FIELD_INTERVAL, /* datetime */
+ SDB_FIELD_BACKEND, /* string */
+};
+
+#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" : "unknown")
+
+/*
+ * sdb_store_clear:
+ * Clear the entire store and remove all stored objects.
+ */
+void
+sdb_store_clear(void);
+
/*
* sdb_store_host:
* Add/update a host in the store. If the host, identified by its
int
sdb_store_host(const char *name, sdb_time_t last_update);
+/*
+ * sdb_store_has_host:
+ * sdb_store_get_host:
+ * Query the store for a host by its (canonicalized) name.
+ *
+ * sdb_store_get_host increments the ref count of the host object. The caller
+ * needs to deref it when no longer using it.
+ */
_Bool
sdb_store_has_host(const char *name);
+sdb_store_obj_t *
+sdb_store_get_host(const char *name);
+
/*
* sdb_store_attribute:
* Add/update a host's attribute in the store. If the attribute, identified by
* - a negative value on error
*/
int
-sdb_store_attribute(const char *hostname, const char *key, const char *value,
+sdb_store_attribute(const char *hostname,
+ const char *key, const sdb_data_t *value,
sdb_time_t last_update);
/*
* sdb_store_service:
- * Add/update a store in the store. If the service, identified by its name,
+ * Add/update a service in the store. If the service, identified by its name,
* already exists for the specified host, it will be updated according to the
* 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
sdb_store_service(const char *hostname, const char *name,
sdb_time_t last_update);
+/*
+ * sdb_store_service_attr:
+ * Add/update a service's attribute in the store. If the attribute, identified
+ * by its key, already exists for the specified service, it will be updated to
+ * the specified value. If the references service (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_service_attr(const char *hostname, const char *service,
+ const char *key, const sdb_data_t *value, sdb_time_t last_update);
+
+/*
+ * A metric store describes how to access a metric's data.
+ */
+typedef struct {
+ const char *type;
+ const char *id;
+} sdb_metric_store_t;
+
+/*
+ * 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.
+ *
+ * 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
+ */
+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_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:
+ * Creates an arithmetic expression implementing the specified operator on the
+ * specified left and right operand.
+ *
+ * Returns:
+ * - an expression object on success
+ * - NULL else
+ */
+sdb_store_expr_t *
+sdb_store_expr_create(int op, sdb_store_expr_t *left, sdb_store_expr_t *right);
+
+/*
+ * 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.
+ *
+ * Returns:
+ * - an expression object on success
+ * - NULL else
+ */
+sdb_store_expr_t *
+sdb_store_expr_constvalue(const sdb_data_t *value);
+
+/*
+ * sdb_store_expr_eval:
+ * 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_store_obj_t *obj,
+ sdb_data_t *res, sdb_store_matcher_t *filter);
+
+/*
+ * Conditionals may be used to lookup hosts from the store based on a
+ * conditional expression.
+ *
+ * A conditional object inherits from sdb_object_t and, thus, may safely be
+ * cast to a generic object.
+ */
+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_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_cond_t *
+sdb_store_attr_cond(const char *name, sdb_store_expr_t *expr);
+
+/*
+ * 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_cond_t *
+sdb_store_obj_cond(int field, sdb_store_expr_t *expr);
+
+/*
+ * 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_matcher_t *
+sdb_store_name_matcher(int type, const char *name, _Bool re);
+
+/*
+ * 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_matcher_t *
+sdb_store_attr_matcher(const char *name, const char *value, _Bool re);
+
+/*
+ * sdb_store_isnull_matcher:
+ * Creates a matcher matching NULL values.
+ */
+sdb_store_matcher_t *
+sdb_store_isnull_matcher(sdb_store_expr_t *expr);
+
+/*
+ * sdb_store_isnnull_matcher:
+ * Creates a matcher matching non-NULL values.
+ */
+sdb_store_matcher_t *
+sdb_store_isnnull_matcher(sdb_store_expr_t *expr);
+
+/*
+ * sdb_store_child_matcher:
+ * Creates a matcher matching an object's children of the specified type. It
+ * matches if *any* of those children match 'm'.
+ */
+sdb_store_matcher_t *
+sdb_store_child_matcher(int type, sdb_store_matcher_t *m);
+
+/*
+ * 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.
+ */
+sdb_store_matcher_t *
+sdb_store_lt_matcher(sdb_store_cond_t *cond);
+sdb_store_matcher_t *
+sdb_store_le_matcher(sdb_store_cond_t *cond);
+sdb_store_matcher_t *
+sdb_store_eq_matcher(sdb_store_cond_t *cond);
+sdb_store_matcher_t *
+sdb_store_ge_matcher(sdb_store_cond_t *cond);
+sdb_store_matcher_t *
+sdb_store_gt_matcher(sdb_store_cond_t *cond);
+
+sdb_store_matcher_t *
+sdb_store_cmp_lt(sdb_store_expr_t *left, sdb_store_expr_t *right);
+sdb_store_matcher_t *
+sdb_store_cmp_le(sdb_store_expr_t *left, sdb_store_expr_t *right);
+sdb_store_matcher_t *
+sdb_store_cmp_eq(sdb_store_expr_t *left, sdb_store_expr_t *right);
+sdb_store_matcher_t *
+sdb_store_cmp_ne(sdb_store_expr_t *left, sdb_store_expr_t *right);
+sdb_store_matcher_t *
+sdb_store_cmp_ge(sdb_store_expr_t *left, sdb_store_expr_t *right);
+sdb_store_matcher_t *
+sdb_store_cmp_gt(sdb_store_expr_t *left, sdb_store_expr_t *right);
+
+/*
+ * 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_in_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
+
+/*
+ * 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_regex_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
+
+/*
+ * 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_nregex_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
+
+/*
+ * sdb_store_matcher_op_cb:
+ * Callback constructing a matcher operator.
+ */
+typedef sdb_store_matcher_t *(*sdb_store_matcher_op_cb)
+ (sdb_store_expr_t *, sdb_store_expr_t *);
+
+/*
+ * 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
+ */
+sdb_store_matcher_op_cb
+sdb_store_parse_matcher_op(const char *op);
+
+/*
+ * sdb_store_parse_object_type_plural:
+ * Parse the type name (plural) of a stored object.
+ *
+ * Returns:
+ * - the object type on success
+ * - a negative value else
+ */
+int
+sdb_store_parse_object_type_plural(const char *name);
+
+/*
+ * sdb_store_parse_field_name:
+ * Parse the name of a stored object's queryable field.
+ *
+ * Returns:
+ * - the field id on success
+ * - a negative value else
+ */
+int
+sdb_store_parse_field_name(const char *name);
+
+/*
+ * sdb_store_matcher_parse_cmp:
+ * Parse a simple compare expression (<obj_type>.<attr> <op> <expression>).
+ *
+ * Returns:
+ * - a matcher object on success
+ * - NULL else
+ */
+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_matcher_parse_field_cmp:
+ * Parse a simple compare expression for queryable object fields (<field> <op>
+ * <expression>).
+ *
+ * Returns:
+ * - a matcher object on success
+ * - NULL else
+ */
+sdb_store_matcher_t *
+sdb_store_matcher_parse_field_cmp(const char *name, const char *op,
+ sdb_store_expr_t *expr);
+
+/*
+ * sdb_store_dis_matcher:
+ * Creates a matcher matching the disjunction (logical OR) of two matchers.
+ */
+sdb_store_matcher_t *
+sdb_store_dis_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right);
+
+/*
+ * sdb_store_con_matcher:
+ * Creates a matcher matching the conjunction (logical AND) of two matchers.
+ */
+sdb_store_matcher_t *
+sdb_store_con_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right);
+
+/*
+ * sdb_store_con_matcher::
+ * Creates a matcher matching the inverse (logical NOT) of a matcher.
+ */
+sdb_store_matcher_t *
+sdb_store_inv_matcher(sdb_store_matcher_t *m);
+
+/*
+ * sdb_store_matcher_matches:
+ * Check whether the specified matcher matches the specified store object. If
+ * specified, the filter will be used to preselect objects for further
+ * evaluation. It is applied to any object that's used during the evaluation
+ * of the matcher. Only those objects matching the filter will be considered.
+ *
+ * Note that the filter is applied to all object types (hosts, service,
+ * 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
+ * - 0 else
+ */
+int
+sdb_store_matcher_matches(sdb_store_matcher_t *m, sdb_store_obj_t *obj,
+ sdb_store_matcher_t *filter);
+
+/*
+ * 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.
+ */
+typedef int (*sdb_store_lookup_cb)(sdb_store_obj_t *obj, void *user_data);
+
+/*
+ * 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.
+ *
+ * Returns:
+ * - 0 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);
+
+/*
+ * Flags for serialization functions.
+ *
+ * By default, the full host object will be included in the serialized output.
+ * When specifying any of the flags, the respective information will be left
+ * out. The SKIP_EMPTY flags may be used to skip host objects entirely.
+ */
+enum {
+ SDB_SKIP_ATTRIBUTES = 1 << 0,
+ SDB_SKIP_SERVICES = 1 << 1,
+ SDB_SKIP_METRICS = 1 << 2,
+ SDB_SKIP_SERVICE_ATTRIBUTES = 1 << 3,
+
+ SDB_SKIP_ALL = (1 << 8) - 1,
+
+ /* skip hosts if they do not reference any services/metrics */
+ SDB_SKIP_EMPTY_SERVICES = 1 << 8,
+ SDB_SKIP_EMPTY_METRICS = 1 << 9,
+};
+
/*
* sdb_store_tojson:
* Serialize the entire store to JSON and append the result to the specified
- * buffer.
+ * buffer. If specified, only objects matching the filter will be included in
+ * the result (see sdb_store_host_tojson for details).
+ *
+ * Returns:
+ * - 0 on success
+ * - a negative value on error
+ */
+int
+sdb_store_tojson(sdb_strbuf_t *buf, sdb_store_matcher_t *filter, int flags);
+
+/*
+ * sdb_store_host_tojson:
+ * Serialize a host object to JSON and append the result to the specified
+ * buffer. If specified, only objects matching the filter will be included in
+ * the result. The filter is applied to each object individually and, thus,
+ * should not be of any object-type specific kind. The filter is never applied
+ * to the specified host object; the caller is responsible for this and for
+ * correctly handling skipped hosts.
*
* Returns:
* - 0 on success
* - a negative value on error
*/
int
-sdb_store_tojson(sdb_strbuf_t *buf);
+sdb_store_host_tojson(sdb_store_obj_t *host, sdb_strbuf_t *buf,
+ sdb_store_matcher_t *filter, int flags);
+
+/*
+ * sdb_store_iter_cb:
+ * Store iterator callback. Iteration stops if the callback returns non-zero.
+ */
+typedef int (*sdb_store_iter_cb)(sdb_store_obj_t *obj, void *user_data);
+
+/*
+ * 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.
+ *
+ * Returns:
+ * - 0 on success
+ * - a negative value else
+ */
+int
+sdb_store_iterate(sdb_store_iter_cb cb, void *user_data);
#ifdef __cplusplus
} /* extern "C" */