Provide syntax content to parse: Raptor RDF Syntax Library Manual

+Provide syntax content to parse

The operation of turning syntax into RDF triples has several +alternatives from functions that do most of the work starting from a +URI to functions that allow passing in data buffers.

Parsing and MIME Types

+The mime type of the retrieved content is not used to choose +a parser unless the parser is of type guess. +The guess parser will send an Accept: header +for all known parser syntax mime types (if a URI request is made) +and based on the response, including the identifiers used, +pick the appropriate parser to execute. See +raptor_world_guess_parser_name() +for a full discussion of the inputs to the guessing. +

+Parse the content from a URI (`raptor_parser_parse_uri()`)

The URI is resolved and the content read from it and passed to +the parser: +

+  raptor_parser_parse_uri(rdf_parser, uri, base_uri);
+

+The base_uri is optional (can be +NULL) and will default to the +uri. +

+Parse the content of a URI using an existing WWW connection (`raptor_parser_parse_uri_with_connection()`)

The URI is resolved using an existing WWW connection (for +example a libcurl CURL handle) to allow for any existing +WWW configuration to be reused. See +raptor_new_www_with_connection +for full details of how this works. The content is then read from the +result of resolving the URI: +

+  raptor_parser_parse_uri_with_connection(rdf_parser, uri, base_uri, connection);
+

+The base_uri is optional (can be +NULL) and will default to the +uri. +

+Parse the content of a C `FILE*` (`raptor_parser_parse_file_stream()`)

Parsing can read from a C STDIO file handle: +

+  stream = fopen(filename, "rb");
+  raptor_parser_parse_file_stream(rdf_parser, stream, filename, base_uri);
+  fclose(stream);
+

+This function can use take an optional filename which +is used in locator error messages. +The base_uri may be required by some parsers +and if NULL will cause the parsing to fail. +This requirement can be checked by looking at the flags in +the parser description using +raptor_world_get_parser_description(). +

+Parse the content of a file URI (`raptor_parser_parse_file()`)

Parsing can read from a URI known to be a file: URI: +

+  raptor_parser_parse_file(rdf_parser, file_uri, base_uri);
+

+This function requires that the file_uri is +a file URI, that is +raptor_uri_uri_string_is_file_uri( raptor_uri_as_string( file_uri) ) +must be true. +The base_uri may be required by some parsers +and if NULL will cause the parsing to fail. +

+Parse chunks of syntax content provided by the application (`raptor_parser_parse_start()` and `raptor_parser_parse_chunk()`)

+  raptor_parser_parse_start(rdf_parser, base_uri);
+  while(/* not finished getting content */) {
+    unsigned char *buffer;
+    size_t buffer_len;
+
+    /* ... obtain some syntax content in buffer of size buffer_len bytes ... */
+
+    raptor_parser_parse_chunk(rdf_parser, buffer, buffer_len, 0);
+  }
+  raptor_parser_parse_chunk(rdf_parser, NULL, 0, 1); /* no data and is_end = 1 */
+

+The base_uri argument to +raptor_parser_parse_start() +may be required by some parsers +and if NULL will cause the parsing to fail. +

On the last +raptor_parser_parse_chunk() +call, or after the loop is ended, the is_end +parameter must be set to non-0. Content can be passed with the +final call. If no content is present at the end (such as in +some kind of “end of file” situation), then a 0-length +buffer_len or NULL buffer can be used.

The minimal case is an entire parse in one chunk as follows:

+  raptor_parser_parse_start(rdf_parser, base_uri);
+  raptor_parser_parse_chunk(rdf_parser, buffer, buffer_len, 1); /* is_end = 1 */
+