Extracting FBTs

We provide collect-fbts as a utility for collecting strings.

php ./vendor/bin/fbt collect-fbts --path=./path/to/fbt/ --src=./path/to/project/

Options:

name	default	description
--src=`[path]`	none	Cache storage path for source strings
--path=`[path]`	none	The directory where you want to scan usages of fbt in php files.
--fbt-common-path=`[path]`	none	Optional path to the common strings module. This is a map from {[text]: [description]}.

⚠️ Unlike Facebook's version of fbt, we primarily collect <fbt> & translate strings during script execution.

Upon successful execution, the output of the /your/path/to/fbt/.source_strings.json will be in the following format:

[
  "phrases": [
    [
      "hashToText": [
        <hash>: <text>,
        ...
      ],
      "type": "text" | "table",
      "desc": <description>,
      "project": <project>,
      "jsfbt": string | ['t' => <table>, 'm' => <metadata>],
    ]
  ],
  "childParentMappings" => [
    <childIdx>: <parentIdx>
  ]
}

phrases here represents all the source information we need to process and produce an fbt::_(...) callsite's final payload. When combined with corresponding translations to each hashToText entry we can produce the translated payloads fbt::_() expects.

When it comes to moving from source text to translations, what is most pertinent is the hashToText payload containing all relevant texts with their identifying hash. You can choose md5 or tiger hash module. It defaults to md5.

A note on hashes

In the FBT framework, there are 2 main places we uses hashes for identification: text and fbt callsite. The hashToText mapping above represents the hash of the text and its description. This is used when building the translated payloads.

The hash of the callsite (defaulting to jenkins hash) is used to look up the payload in FbtTranslations. This is basically the hash of the object you see in jsfbt.

See Translating FBTs for getting your translations in the right format.

Options:#

A note on hashes#

Options:

A note on hashes