Using the schema compiler {#flatbuffers_guide_using_schema_compiler}
=========================
Usage:
flatc [ GENERATOR OPTIONS ] [ -o PATH ] [ -I PATH ] [ -S ] FILES...
[ -- FILES...]
The files are read and parsed in order, and can contain either schemas
or data (see below). Data files are processed according to the definitions of
the most recent schema specified.
`--` indicates that the following files are binary files in
FlatBuffer format conforming to the schema indicated before it.
Depending on the flags passed, additional files may
be generated for each file processed:
For any schema input files, one or more generators can be specified:
- `--cpp`, `-c` : Generate a C++ header for all definitions in this file (as
`filename_generated.h`).
- `--java`, `-j` : Generate Java code.
- `--csharp`, `-n` : Generate C# code.
- `--go`, `-g` : Generate Go code.
- `--python`, `-p`: Generate Python code.
- `--js`, `-s`: Generate JavaScript code.
- `--php`: Generate PHP code.
- `--grpc`: Generate RPC stub code for GRPC.
For any data input files:
- `--binary`, `-b` : If data is contained in this file, generate a
`filename.bin` containing the binary flatbuffer (or a different extension
if one is specified in the schema).
- `--json`, `-t` : If data is contained in this file, generate a
`filename.json` representing the data in the flatbuffer.
Additional options:
- `-o PATH` : Output all generated files to PATH (either absolute, or
relative to the current directory). If omitted, PATH will be the
current directory. PATH should end in your systems path separator,
e.g. `/` or `\`.
- `-I PATH` : when encountering `include` statements, attempt to load the
files from this path. Paths will be tried in the order given, and if all
fail (or none are specified) it will try to load relative to the path of
the schema file being parsed.
- `-M` : Print make rules for generated files.
- `--strict-json` : Require & generate strict JSON (field names are enclosed
in quotes, no trailing commas in tables/vectors). By default, no quotes are
required/generated, and trailing commas are allowed.
- `--defaults-json` : Output fields whose value is equal to the default value
when writing JSON text.
- `--no-prefix` : Don't prefix enum values in generated C++ by their enum
type.
- `--scoped-enums` : Use C++11 style scoped and strongly typed enums in
generated C++. This also implies `--no-prefix`.
- `--gen-includes` : (deprecated), this is the default behavior.
If the original behavior is required (no include
statements) use `--no-includes.`
- `--no-includes` : Don't generate include statements for included schemas the
generated file depends on (C++).
- `--gen-mutable` : Generate additional non-const accessors for mutating
FlatBuffers in-place.
`--gen-object-api` : Generate an additional object-based API. This API is
more convenient for object construction and mutation than the base API,
at the cost of efficiency (object allocation). Recommended only to be used
if other options are insufficient.
- `--gen-onefile` : Generate single output file (useful for C#)
- `--gen-all`: Generate not just code for the current schema files, but
for all files it includes as well. If the language uses a single file for
output (by default the case for C++ and JS), all code will end up in
this one file.
- `--no-js-exports` : Removes Node.js style export lines (useful for JS)
- `--goog-js-export` : Uses goog.exportsSymbol and goog.exportsProperty
instead of Node.js style exporting. Needed for compatibility with the
Google closure compiler (useful for JS).
- `--raw-binary` : Allow binaries without a file_indentifier to be read.
This may crash flatc given a mismatched schema.
- `--proto`: Expect input files to be .proto files (protocol buffers).
Output the corresponding .fbs file.
Currently supports: `package`, `message`, `enum`, nested declarations,
`import` (use `-I` for paths), `extend`, `oneof`, `group`.
Does not support, but will skip without error: `option`, `service`,
`extensions`, and most everything else.
- `--schema`: Serialize schemas instead of JSON (use with -b). This will
output a binary version of the specified schema that itself corresponds
to the reflection/reflection.fbs schema. Loading this binary file is the
basis for reflection functionality.
- `--bfbs-comments`: Add doc comments to the binary schema files.
- `--conform FILE` : Specify a schema the following schemas should be
an evolution of. Gives errors if not. Useful to check if schema
modifications don't break schema evolution rules.
- `--include-prefix PATH` : Prefix this path to any generated include
statements.
- `--keep-prefix` : Keep original prefix of schema include statement.
- `--reflect-types` : Add minimal type reflection to code generation.
- `--reflect-names` : Add minimal type/name reflection.
NOTE: short-form options for generators are deprecated, use the long form
whenever possible.