1 Using the schema compiler {#flatbuffers_guide_using_schema_compiler} 2 ========================= 3 4 Usage: 5 6 flatc [ GENERATOR OPTIONS ] [ -o PATH ] [ -I PATH ] [ -S ] FILES... 7 [ -- FILES...] 8 9 The files are read and parsed in order, and can contain either schemas 10 or data (see below). Data files are processed according to the definitions of 11 the most recent schema specified. 12 13 `--` indicates that the following files are binary files in 14 FlatBuffer format conforming to the schema indicated before it. 15 16 Depending on the flags passed, additional files may 17 be generated for each file processed: 18 19 For any schema input files, one or more generators can be specified: 20 21 - `--cpp`, `-c` : Generate a C++ header for all definitions in this file (as 22 `filename_generated.h`). 23 24 - `--java`, `-j` : Generate Java code. 25 26 - `--csharp`, `-n` : Generate C# code. 27 28 - `--go`, `-g` : Generate Go code. 29 30 - `--python`, `-p`: Generate Python code. 31 32 - `--js`, `-s`: Generate JavaScript code. 33 34 - `--php`: Generate PHP code. 35 36 - `--grpc`: Generate RPC stub code for GRPC. 37 38 For any data input files: 39 40 - `--binary`, `-b` : If data is contained in this file, generate a 41 `filename.bin` containing the binary flatbuffer (or a different extension 42 if one is specified in the schema). 43 44 - `--json`, `-t` : If data is contained in this file, generate a 45 `filename.json` representing the data in the flatbuffer. 46 47 Additional options: 48 49 - `-o PATH` : Output all generated files to PATH (either absolute, or 50 relative to the current directory). If omitted, PATH will be the 51 current directory. PATH should end in your systems path separator, 52 e.g. `/` or `\`. 53 54 - `-I PATH` : when encountering `include` statements, attempt to load the 55 files from this path. Paths will be tried in the order given, and if all 56 fail (or none are specified) it will try to load relative to the path of 57 the schema file being parsed. 58 59 - `-M` : Print make rules for generated files. 60 61 - `--strict-json` : Require & generate strict JSON (field names are enclosed 62 in quotes, no trailing commas in tables/vectors). By default, no quotes are 63 required/generated, and trailing commas are allowed. 64 65 - `--defaults-json` : Output fields whose value is equal to the default value 66 when writing JSON text. 67 68 - `--no-prefix` : Don't prefix enum values in generated C++ by their enum 69 type. 70 71 - `--scoped-enums` : Use C++11 style scoped and strongly typed enums in 72 generated C++. This also implies `--no-prefix`. 73 74 - `--gen-includes` : (deprecated), this is the default behavior. 75 If the original behavior is required (no include 76 statements) use `--no-includes.` 77 78 - `--no-includes` : Don't generate include statements for included schemas the 79 generated file depends on (C++). 80 81 - `--gen-mutable` : Generate additional non-const accessors for mutating 82 FlatBuffers in-place. 83 84 `--gen-object-api` : Generate an additional object-based API. This API is 85 more convenient for object construction and mutation than the base API, 86 at the cost of efficiency (object allocation). Recommended only to be used 87 if other options are insufficient. 88 89 - `--gen-onefile` : Generate single output file (useful for C#) 90 91 - `--gen-all`: Generate not just code for the current schema files, but 92 for all files it includes as well. If the language uses a single file for 93 output (by default the case for C++ and JS), all code will end up in 94 this one file. 95 96 - `--no-js-exports` : Removes Node.js style export lines (useful for JS) 97 98 - `--goog-js-export` : Uses goog.exportsSymbol and goog.exportsProperty 99 instead of Node.js style exporting. Needed for compatibility with the 100 Google closure compiler (useful for JS). 101 102 - `--raw-binary` : Allow binaries without a file_indentifier to be read. 103 This may crash flatc given a mismatched schema. 104 105 - `--proto`: Expect input files to be .proto files (protocol buffers). 106 Output the corresponding .fbs file. 107 Currently supports: `package`, `message`, `enum`, nested declarations, 108 `import` (use `-I` for paths), `extend`, `oneof`, `group`. 109 Does not support, but will skip without error: `option`, `service`, 110 `extensions`, and most everything else. 111 112 - `--schema`: Serialize schemas instead of JSON (use with -b). This will 113 output a binary version of the specified schema that itself corresponds 114 to the reflection/reflection.fbs schema. Loading this binary file is the 115 basis for reflection functionality. 116 117 - `--bfbs-comments`: Add doc comments to the binary schema files. 118 119 - `--conform FILE` : Specify a schema the following schemas should be 120 an evolution of. Gives errors if not. Useful to check if schema 121 modifications don't break schema evolution rules. 122 123 - `--include-prefix PATH` : Prefix this path to any generated include 124 statements. 125 126 - `--keep-prefix` : Keep original prefix of schema include statement. 127 128 - `--reflect-types` : Add minimal type reflection to code generation. 129 - `--reflect-names` : Add minimal type/name reflection. 130 131 NOTE: short-form options for generators are deprecated, use the long form 132 whenever possible. 133
