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index 574b01ed262adcfd88d2a6be63afdff7285300a9..0cee91362998d55c4f329c031572d5096e68400c 100644 (file)
--- a/src/include/core/store.h
+++ b/src/include/core/store.h
#include "core/object.h"
#include "core/data.h"
#include "core/time.h"
+#include "core/timeseries.h"
+#include "parser/ast.h"
#include "utils/strbuf.h"
+#include <stdbool.h>
#include <stdio.h>
#ifdef __cplusplus
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 */
+ SDB_FIELD_TIMESERIES, /* metrics only; type: boolean */
};
#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" \
+ : ((f) == SDB_FIELD_TIMESERIES) ? "timeseries" \
+ : "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 */ \
+ : ((f) == SDB_FIELD_TIMESERIES) ? SDB_TYPE_BOOLEAN \
+ : -1)
+
+/*
+ * sdb_store_t represents an in-memory store. It inherits from sdb_object_t
+ * and may safely be case to a generic object.
+ */
+struct sdb_store;
+typedef struct sdb_store sdb_store_t;
+#define SDB_STORE(obj) ((sdb_store_t *)(obj))
+
+/*
+ * sdb_store_obj_t represents the super-class of any stored object. 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;
+/*
+ * sdb_store_host_t represents the meta-data of a stored host object.
+ */
+typedef struct {
+ const char *name;
+
+ sdb_time_t last_update;
+ sdb_time_t interval;
+ const char * const *backends;
+ size_t backends_num;
+} sdb_store_host_t;
/*
- * 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.
+ * sdb_store_service_t represents the meta-data of a stored service object.
*/
-struct sdb_store_obj;
-typedef struct sdb_store_obj sdb_store_obj_t;
+typedef struct {
+ const char *hostname;
+ const char *name;
+
+ sdb_time_t last_update;
+ sdb_time_t interval;
+ const char * const *backends;
+ size_t backends_num;
+} sdb_store_service_t;
/*
- * sdb_store_clear:
- * Clear the entire store and remove all stored objects.
+ * sdb_metric_store_t specifies how to access a metric's data.
*/
-void
-sdb_store_clear(void);
+typedef struct {
+ const char *type;
+ const char *id;
+} sdb_metric_store_t;
/*
- * sdb_store_host:
- * Add/update a host in the store. If the host, identified by its
- * canonicalized name, already exists, it will be updated according to the
- * specified name and timestamp. 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.
+ * sdb_store_metric_t represents the meta-data of a stored metric object.
+ */
+typedef struct {
+ const char *hostname;
+ const char *name;
+ struct {
+ const char *type;
+ const char *id;
+ } store;
+
+ sdb_time_t last_update;
+ sdb_time_t interval;
+ const char * const *backends;
+ size_t backends_num;
+} sdb_store_metric_t;
+
+/*
+ * sdb_store_attribute_t represents a stored attribute.
+ */
+typedef struct {
+ const char *hostname; /* optional */
+ int parent_type;
+ const char *parent;
+ const char *key;
+ sdb_data_t value;
+
+ sdb_time_t last_update;
+ sdb_time_t interval;
+ const char * const *backends;
+ size_t backends_num;
+} sdb_store_attribute_t;
+
+/*
+ * Expressions represent arithmetic expressions based on stored objects and
+ * their various attributes.
*
- * Returns:
+ * 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.
+ */
+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
+ *
+ * A JSON formatter object inherits from sdb_object_t and, thus, may safely be
+ * cast to a generic object.
+ */
+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.
+ *
+ * Any of the call-back functions shall return:
* - 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
*/
+typedef struct {
+ /*
+ * store_host:
+ * Add/update a host in the store. If the host, identified by its
+ * canonicalized name, already exists, it will be updated according to the
+ * specified name and timestamp. Else, a new entry will be created in the
+ * store.
+ */
+ int (*store_host)(sdb_store_host_t *host, sdb_object_t *user_data);
+
+ /*
+ * store_service:
+ * 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 name and timestamp. If the referenced host
+ * does not exist, an error will be reported. Else, a new entry will be
+ * created in the store.
+ */
+ int (*store_service)(sdb_store_service_t *service, sdb_object_t *user_data);
+
+ /*
+ * 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 attributes. If the referenced host does not
+ * exist, an error will be reported. Else, a new entry will be created in
+ * the store.
+ */
+ int (*store_metric)(sdb_store_metric_t *metric, sdb_object_t *user_data);
+
+ /*
+ * store_attribute:
+ * Add/update a host's attribute in the store. If the attribute,
+ * identified by its key, already exists for the specified host, it will
+ * be updated to the specified values. If the referenced host does not
+ * exist, an error will be reported. Else, a new entry will be created in
+ * the store.
+ */
+ int (*store_attribute)(sdb_store_attribute_t *attr, sdb_object_t *user_data);
+} sdb_store_writer_t;
+
+/*
+ * sdb_store_writer:
+ * A store writer implementation that provides an in-memory object store. It
+ * expects a store object as its user-data argument.
+ */
+extern sdb_store_writer_t sdb_store_writer;
+
+/*
+ * A store reader describes the interface to query a store implementation.
+ */
+typedef struct {
+ /*
+ * prepare_query:
+ * Prepare the query described by 'ast' for execution.
+ */
+ sdb_object_t *(*prepare_query)(sdb_ast_node_t *ast,
+ sdb_strbuf_t *errbuf, sdb_object_t *user_data);
+
+ /*
+ * execute_query:
+ * Execute a previously prepared query. The callback may expect that only
+ * queries prepared by its respective prepare callback will be passed to
+ * this function. The query result will be passed back via the specified
+ * store writer.
+ */
+ int (*execute_query)(sdb_object_t *q,
+ sdb_store_writer_t *w, sdb_object_t *wd,
+ sdb_strbuf_t *errbuf, sdb_object_t *user_data);
+} sdb_store_reader_t;
+
+/*
+ * sdb_store_reader:
+ * A store reader implementation that uses an in-memory object store. It
+ * expects a store object as its user-data argument.
+ */
+extern sdb_store_reader_t sdb_store_reader;
+
+/*
+ * sdb_store_create:
+ * Allocate a new in-memory store.
+ */
+sdb_store_t *
+sdb_store_create(void);
+
+/*
+ * sdb_store_host, sdb_store_service, sdb_store_metric, sdb_store_attribute,
+ * sdb_store_metric_attr:
+ * Store an object in the specified store. The hostname is expected to be
+ * canonical.
+ */
int
-sdb_store_host(const char *name, sdb_time_t last_update);
+sdb_store_host(sdb_store_t *store, const char *name, sdb_time_t last_update);
+int
+sdb_store_service(sdb_store_t *store, const char *hostname, const char *name,
+ sdb_time_t last_update);
+int
+sdb_store_metric(sdb_store_t *store, const char *hostname, const char *name,
+ sdb_metric_store_t *metric_store, sdb_time_t last_update);
+int
+sdb_store_attribute(sdb_store_t *store, const char *hostname,
+ const char *key, const sdb_data_t *value, sdb_time_t last_update);
+int
+sdb_store_service_attr(sdb_store_t *store, const char *hostname,
+ const char *service, const char *key, const sdb_data_t *value,
+ sdb_time_t last_update);
+int
+sdb_store_metric_attr(sdb_store_t *store, const char *hostname,
+ const char *metric, const char *key, const sdb_data_t *value,
+ sdb_time_t last_update);
/*
- * sdb_store_has_host:
* sdb_store_get_host:
- * Query the store for a host by its (canonicalized) name.
+ * Query the specified 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.
+ * The function 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_get_host(sdb_store_t *store, const char *name);
/*
- * sdb_store_attribute:
- * Add/update a host's attribute in the store. If the attribute, identified by
- * its key, already exists for the specified host, it will be updated to the
- * specified values. 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 and managed by the store
- * itself.
+ * 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. The host data is
+ * retrieved from the specified store.
*
* 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
+ * - a negative value else
*/
int
-sdb_store_attribute(const char *hostname,
- const char *key, const sdb_data_t *value,
- sdb_time_t last_update);
+sdb_store_fetch_timeseries(sdb_store_t *store,
+ 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_service:
- * 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.
+ * 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.
*
* 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
+ * - a negative value else
*/
int
-sdb_store_service(const char *hostname, const char *name,
- sdb_time_t last_update);
+sdb_store_get_field(sdb_store_obj_t *obj, int field, sdb_data_t *res);
/*
- * 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.
+ * 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 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
+ * - 0 if the attribute exists
+ * - a negative value else
*/
int
-sdb_store_service_attr(const char *hostname, const char *service,
- const char *key, const sdb_data_t *value, sdb_time_t last_update);
+sdb_store_get_attr(sdb_store_obj_t *obj, const char *name, sdb_data_t *res,
+ sdb_store_matcher_t *filter);
/*
- * Expressions specify arithmetic expressions.
+ * Querying a store:
*
- * A expression object inherits from sdb_object_t and, thus, may safely be
- * cast to a generic object.
+ * - Query interface: A query is a formal description of an interaction with
+ * the store. It can be used, both, for read and write access. The query is
+ * described by its abstract syntax tree (AST). The parser package provides
+ * means to parse a string (SysQL) representation of the query into an AST.
+ *
+ * - Matcher / expression interface: This low-level interface provides direct
+ * control over how to access the store. It is used by the query
+ * implementation internally and can only be used for read access.
*/
-struct sdb_store_expr;
-typedef struct sdb_store_expr sdb_store_expr_t;
-#define SDB_STORE_EXPR(obj) ((sdb_store_expr_t *)(obj))
+
+/*
+ * sdb_store_query_t:
+ * A parsed query readily prepared for execution.
+ */
+struct sdb_store_query;
+typedef struct sdb_store_query sdb_store_query_t;
+
+/*
+ * sdb_store_query_prepare:
+ * Prepare the query described by 'ast' for execution in a store.
+ *
+ * Returns:
+ * - a store query on success
+ * - NULL else
+ */
+sdb_store_query_t *
+sdb_store_query_prepare(sdb_ast_node_t *ast);
+
+/*
+ * sdb_store_query_prepare_matcher:
+ * Prepare the logical expression described by 'ast' for execution as a store
+ * matcher.
+ *
+ * Returns:
+ * - a matcher on success
+ * - NULL else
+ */
+sdb_store_matcher_t *
+sdb_store_query_prepare_matcher(sdb_ast_node_t *ast);
+
+/*
+ * sdb_store_query_execute:
+ * Execute a previously prepared query in the specified store. The query
+ * result will be written to 'buf' and any errors to 'errbuf'.
+ *
+ * Returns:
+ * - the result type (to be used by the server reply)
+ * - a negative value on error
+ */
+int
+sdb_store_query_execute(sdb_store_t *store, sdb_store_query_t *m,
+ sdb_store_writer_t *w, sdb_object_t *wd, sdb_strbuf_t *errbuf);
/*
* sdb_store_expr_create:
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.
/*
* 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);
/*
- * 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).
*
- * 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.
*/
-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_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_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_dis_matcher:
+ * Creates a matcher matching the disjunction (logical OR) 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_dis_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right);
/*
- * 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_con_matcher:
+ * Creates a matcher matching the conjunction (logical AND) of two matchers.
*/
-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_con_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right);
/*
- * 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_inv_matcher::
+ * Creates a matcher matching the inverse (logical NOT) of a matcher.
*/
sdb_store_matcher_t *
-sdb_store_name_matcher(int type, const char *name, _Bool re);
+sdb_store_inv_matcher(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_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.
*/
sdb_store_matcher_t *
-sdb_store_attr_matcher(const char *name, const char *value, _Bool re);
+sdb_store_any_matcher(sdb_store_expr_t *iter, sdb_store_matcher_t *m);
/*
- * sdb_store_isnull_matcher:
- * Creates a matcher matching "missing" attributes.
+ * 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_isnull_matcher(const char *attr_name);
+sdb_store_all_matcher(sdb_store_expr_t *iter, sdb_store_matcher_t *m);
+
+/*
+ * 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_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_expr_t *left, sdb_store_expr_t *right);
sdb_store_matcher_t *
-sdb_store_le_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_eq_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_ge_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_cond_t *cond);
+sdb_store_gt_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
/*
- * 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_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_istrue_matcher, sdb_store_isfalse_matcher:
+ * Creates a matcher matching boolean values.
*/
sdb_store_matcher_t *
-sdb_store_inv_matcher(sdb_store_matcher_t *m);
+sdb_store_istrue_matcher(sdb_store_expr_t *expr);
+sdb_store_matcher_t *
+sdb_store_isfalse_matcher(sdb_store_expr_t *expr);
/*
* sdb_store_matcher_matches:
- * Check whether the specified matcher matches the specified store object.
+ * 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_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.
+ * 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, void *user_data);
+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 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.
+ * Look up objects of the specified type in the specified store. The specified
+ * callback function is called for each object in the store matching 'm'. The
+ * function performs a full scan of all stored objects. 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_lookup_cb cb,
- void *user_data);
+sdb_store_scan(sdb_store_t *store, int type,
+ 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 object will be included in the serialized output. When
- * specifying any of the flags, the respective information will be left out.
+ * Flags for JSON formatting.
*/
enum {
- SDB_SKIP_ATTRIBUTES = 1 << 0,
- SDB_SKIP_SERVICES = 1 << 1,
- SDB_SKIP_SERVICE_ATTRIBUTES = 1 << 2,
-
- SDB_SKIP_ALL = 0xffff,
+ SDB_WANT_ARRAY = 1 << 0,
};
/*
- * sdb_store_tojson:
- * Serialize the entire store to JSON and append the result to the specified
- * buffer.
+ * 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_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_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 on error
+ * - a negative value else
*/
int
-sdb_store_tojson(sdb_strbuf_t *buf, int flags);
+sdb_store_emit(sdb_store_obj_t *obj, sdb_store_writer_t *w, sdb_object_t *wd);
/*
- * sdb_store_host_tojson:
- * Serialize a host object to JSON and append the result to the specified
- * buffer.
+ * sdb_store_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 on error
+ * - a negative value else
*/
int
-sdb_store_host_tojson(sdb_store_obj_t *host, sdb_strbuf_t *buf, int flags);
+sdb_store_emit_full(sdb_store_obj_t *obj, sdb_store_matcher_t *filter,
+ sdb_store_writer_t *w, sdb_object_t *wd);
/*
- * sdb_store_iter_cb:
- * Store iterator callback. Iteration stops if the callback returns non-zero.
+ * sdb_store_json_finish:
+ * Finish the JSON output. This function has to be called once after emiting
+ * all objects.
*/
-typedef int (*sdb_store_iter_cb)(sdb_store_obj_t *obj, void *user_data);
+int
+sdb_store_json_finish(sdb_store_json_formatter_t *f);
/*
- * 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
+ * sdb_store_json_writer:
+ * A store writer implementation that generates JSON output. It expects a
+ * store JSON formatter as its user-data argument.
*/
-int
-sdb_store_iterate(sdb_store_iter_cb cb, void *user_data);
+extern sdb_store_writer_t sdb_store_json_writer;
#ifdef __cplusplus
} /* extern "C" */