X-Git-Url: https://git.tokkee.org/?p=sysdb.git;a=blobdiff_plain;f=src%2Finclude%2Fcore%2Fstore.h;h=678af6ff9e706f85a33080ac5a377142e17b0e23;hp=574b01ed262adcfd88d2a6be63afdff7285300a9;hb=a248a2d506d3caf06d3cf5284231df6fc583087e;hpb=a077fb06b0cf27ca51477c76d5520d0c814af8df diff --git a/src/include/core/store.h b/src/include/core/store.h index 574b01e..678af6f 100644 --- a/src/include/core/store.h +++ b/src/include/core/store.h @@ -32,8 +32,11 @@ #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 #include #ifdef __cplusplus @@ -46,127 +49,390 @@ 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 */ + 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; +/* + * 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_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. + * 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_obj; -typedef struct sdb_store_obj sdb_store_obj_t; +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_clear: - * Clear the entire store and remove all stored objects. + * An expression iterator iterates over the values of an iterable expression. */ -void -sdb_store_clear(void); +struct sdb_store_expr_iter; +typedef struct sdb_store_expr_iter sdb_store_expr_iter_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. + * 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. * - * Returns: + * 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)(const char *name, sdb_time_t last_update, + 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)(const char *hostname, const char *name, + sdb_time_t last_update, 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)(const char *hostname, const char *name, + sdb_metric_store_t *store, sdb_time_t last_update, + 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)(const char *hostname, + const char *key, const sdb_data_t *value, sdb_time_t last_update, + sdb_object_t *user_data); + + /* + * 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. + */ + 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); + + /* + * 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. + */ + 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_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. + * + * TODO: Instead of letting the executor write directly to a string buffer + * (which cannot easily be merged with other results), let it hand + * all objects to a store-writer. + */ + int (*execute_query)(sdb_object_t *q, + sdb_strbuf_t *buf, 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(sdb_store_t *store, const char *name, sdb_time_t last_update); int -sdb_store_host(const char *name, sdb_time_t last_update); +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_strbuf_t *buf, sdb_strbuf_t *errbuf); /* * sdb_store_expr_create: @@ -180,6 +446,43 @@ 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. @@ -193,222 +496,254 @@ 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); /* - * 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_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_isnull_matcher(const char *attr_name); +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_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_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. - * - * Returns: - * - 0 on success - * - a negative value on error + * sdb_store_json_formatter: + * Create a JSON formatter for the specified object types writing to the + * specified buffer. */ -int -sdb_store_tojson(sdb_strbuf_t *buf, int flags); +sdb_store_json_formatter_t * +sdb_store_json_formatter(sdb_strbuf_t *buf, int type, int flags); /* - * sdb_store_host_tojson: - * Serialize a host object to JSON and append the result to the specified - * buffer. + * 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 on error + * - a negative value else */ int -sdb_store_host_tojson(sdb_store_obj_t *host, sdb_strbuf_t *buf, 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_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" */