diff options
Diffstat (limited to 'contrib/libucl/doc/api.md')
| -rw-r--r-- | contrib/libucl/doc/api.md | 119 |
1 files changed, 105 insertions, 14 deletions
diff --git a/contrib/libucl/doc/api.md b/contrib/libucl/doc/api.md index 0523f53..3b031d2 100644 --- a/contrib/libucl/doc/api.md +++ b/contrib/libucl/doc/api.md @@ -1,30 +1,75 @@ -Synopsis -======== +# API documentation + +**Table of Contents** *generated with [DocToc](http://doctoc.herokuapp.com/)* + +- [Synopsis](#synopsis) +- [Description](#description) + - [Parser functions](#parser-functions) + - [Emitting functions](#emitting-functions) + - [Conversion functions](#conversion-functions) + - [Generation functions](#generation-functions) + - [Iteration functions](#iteration-functions) + - [Validation functions](#validation-functions) + - [Utility functions](#utility-functions) +- [Parser functions](#parser-functions-1) + - [ucl_parser_new](#ucl_parser_new) + - [ucl_parser_register_macro](#ucl_parser_register_macro) + - [ucl_parser_register_variable](#ucl_parser_register_variable) + - [ucl_parser_add_chunk](#ucl_parser_add_chunk) + - [ucl_parser_add_string](#ucl_parser_add_string) + - [ucl_parser_add_file](#ucl_parser_add_file) + - [ucl_parser_get_object](#ucl_parser_get_object) + - [ucl_parser_get_error](#ucl_parser_get_error) + - [ucl_parser_free](#ucl_parser_free) + - [ucl_pubkey_add](#ucl_pubkey_add) + - [ucl_parser_set_filevars](#ucl_parser_set_filevars) + - [Parser usage example](#parser-usage-example) +- [Emitting functions](#emitting-functions-1) + - [ucl_object_emit](#ucl_object_emit) + - [ucl_object_emit_full](#ucl_object_emit_full) +- [Conversion functions](#conversion-functions-1) +- [Generation functions](#generation-functions-1) + - [ucl_object_new](#ucl_object_new) + - [ucl_object_typed_new](#ucl_object_typed_new) + - [Primitive objects generation](#primitive-objects-generation) + - [ucl_object_fromstring_common](#ucl_object_fromstring_common) +- [Iteration functions](#iteration-functions-1) + - [ucl_iterate_object](#ucl_iterate_object) +- [Validation functions](#validation-functions-1) + - [ucl_object_validate](#ucl_object_validate) + +# Synopsis `#include <ucl.h>` -Description -=========== +# Description Libucl is a parser and `C` API to parse and generate `ucl` objects. Libucl consist of several groups of functions: ### Parser functions -Used to parse `ucl` files and provide interface to extract `ucl` object +Used to parse `ucl` files and provide interface to extract `ucl` object. Currently, `libucl` can parse only full `ucl` documents, for instance, it is impossible to parse a part of document and therefore it is impossible to use `libucl` as a streaming parser. In future, this limitation can be removed. ### Emitting functions -Convert `ucl` objects to some textual or binary representation. +Convert `ucl` objects to some textual or binary representation. Currently, libucl supports the following exports: + +- `JSON` - valid json format (can possibly loose some original data, such as implicit arrays) +- `Config` - human-readable configuration format (losseless) +- `YAML` - embedded yaml format (has the same limitations as `json` output) ### Conversion functions -Help to convert `ucl` objects to C types +Help to convert `ucl` objects to C types. These functions are used to convert `ucl_object_t` to C primitive types, such as numbers, strings or boolean values. ### Generation functions -Allow creating of `ucl` objects from C types +Allow creating of `ucl` objects from C types and creating of complex `ucl` objects, such as hashes or arrays from primitive `ucl` objects, such as numbers or strings. ### Iteration functions -Iterate over `ucl` objects +Iterate over `ucl` complex objects or over a chain of values, for example when a key in an object has multiple values (that can be treated as implicit array or implicit consolidation). + +### Validation functions +Validation functions are used to validate some object `obj` using json-schema compatible object `schema`. Both input and schema must be UCL objects to perform validation. ### Utility functions -Provide basic utilities to manage `ucl` objects +Provide basic utilities to manage `ucl` objects: creating, removing, retaining and releasing reference count and so on. # Parser functions @@ -40,6 +85,7 @@ Creates new parser with the specified flags: - `UCL_PARSER_KEY_LOWERCASE` - lowercase keys parsed - `UCL_PARSER_ZEROCOPY` - try to use zero-copy mode when reading files (in zero-copy mode text chunk being parsed without copying strings so it should exist till any object parsed is used) +- `UCL_PARSER_NO_TIME` - treat time values as strings without parsing them as floats ### ucl_parser_register_macro @@ -87,6 +133,14 @@ while this one won't be parsed correctly: This limitation may possible be removed in future. +### ucl_parser_add_string +~~~C +bool ucl_parser_add_string (struct ucl_parser *parser, + const char *data, size_t len); +~~~ + +This function acts exactly like `ucl_parser_add_chunk` does but if `len` argument is zero, then the string `data` must be zero-terminated and the actual length is calculated up to `\0` character. + ### ucl_parser_add_file ~~~C @@ -314,13 +368,14 @@ This function is used to convert a string `str` of size `len` to an UCL objects - `UCL_STRING_PARSE_BOOLEAN` - parse passed string and detect boolean - `UCL_STRING_PARSE_INT` - parse passed string and detect integer number - `UCL_STRING_PARSE_DOUBLE` - parse passed string and detect integer or float number -- `UCL_STRING_PARSE_NUMBER` - parse passed string and detect number (both float or integer types) -- `UCL_STRING_PARSE` - parse passed string (and detect booleans and numbers) +- `UCL_STRING_PARSE_TIME` - parse time values as floating point numbers +- `UCL_STRING_PARSE_NUMBER` - parse passed string and detect number (both float, integer and time types) +- `UCL_STRING_PARSE` - parse passed string (and detect booleans, numbers and time values) - `UCL_STRING_PARSE_BYTES` - assume that numeric multipliers are in bytes notation, for example `10k` means `10*1024` and not `10*1000` as assumed without this flag If parsing operations fail then the resulting UCL object will be a `UCL_STRING`. A caller should always check the type of the returned object and release it after using. -# Iteration function +# Iteration functions Iteration are used to iterate over UCL compound types: arrays and objects. Moreover, iterations could be performed over the keys with multiple values (implicit arrays). To iterate over an object, an array or a key with multiple values there is a function `ucl_iterate_object`. @@ -345,4 +400,40 @@ while ((obj = ucl_iterate_object (top, &it, true))) { ucl_object_tostring_forced (cur)); } } -~~~
\ No newline at end of file +~~~ + +# Validation functions + +Currently, there is only one validation function called `ucl_object_validate`. It performs validation of object using the specified schema. This function is defined as following: + +## ucl_object_validate +~~~C +bool ucl_object_validate (ucl_object_t *schema, + ucl_object_t *obj, struct ucl_schema_error *err); +~~~ + +This function uses ucl object `schema`, that must be valid in terms of `json-schema` draft v4, to validate input object `obj`. If this function returns `true` then validation procedure has been succeed. Otherwise, `false` is returned and `err` is set to a specific value. If caller set `err` to NULL then this function does not set any error just returning `false`. Error is the structure defined as following: + +~~~C +struct ucl_schema_error { + enum ucl_schema_error_code code; /* error code */ + char msg[128]; /* error message */ + ucl_object_t *obj; /* object where error occured */ +}; +~~~ + +Caller may use `code` field to get a numeric error code: + +~~~C +enum ucl_schema_error_code { + UCL_SCHEMA_OK = 0, /* no error */ + UCL_SCHEMA_TYPE_MISMATCH, /* type of object is incorrect */ + UCL_SCHEMA_INVALID_SCHEMA, /* schema is invalid */ + UCL_SCHEMA_MISSING_PROPERTY,/* missing properties */ + UCL_SCHEMA_CONSTRAINT, /* constraint found */ + UCL_SCHEMA_MISSING_DEPENDENCY, /* missing dependency */ + UCL_SCHEMA_UNKNOWN /* generic error */ +}; +~~~ + +`msg` is a stiring description of an error and `obj` is an object where error has been occurred. Error object is not allocated by libucl, so there is no need to free it after validation (a static object should thus be used).
\ No newline at end of file |
