Text file src/README.vendor

Documentation: Index

     1Vendoring in std and cmd
     2========================
     3
     4The Go command maintains copies of external packages needed by the
     5standard library in the src/vendor and src/cmd/vendor directories.
     6
     7In GOPATH mode, imports of vendored packages are resolved to these
     8directories following normal vendor directory logic
     9(see golang.org/s/go15vendor).
    10
    11In module mode, std and cmd are modules (defined in src/go.mod and
    12src/cmd/go.mod). When a package outside std or cmd is imported
    13by a package inside std or cmd, the import path is interpreted
    14as if it had a "vendor/" prefix. For example, within "crypto/tls",
    15an import of "golang.org/x/crypto/cryptobyte" resolves to
    16"vendor/golang.org/x/crypto/cryptobyte". When a package with the
    17same path is imported from a package outside std or cmd, it will
    18be resolved normally. Consequently, a binary may be built with two
    19copies of a package at different versions if the package is
    20imported normally and vendored by the standard library.
    21
    22Vendored packages are internally renamed with a "vendor/" prefix
    23to preserve the invariant that all packages have distinct paths.
    24This is necessary to avoid compiler and linker conflicts. Adding
    25a "vendor/" prefix also maintains the invariant that standard
    26library packages begin with a dotless path element.
    27
    28The module requirements of std and cmd do not influence version
    29selection in other modules. They are only considered when running
    30module commands like 'go get' and 'go mod vendor' from a directory
    31in GOROOT/src.
    32
    33Maintaining vendor directories
    34==============================
    35
    36Before updating vendor directories, ensure that module mode is enabled.
    37Make sure GO111MODULE=off is not set ('on' or 'auto' should work).
    38
    39Requirements may be added, updated, and removed with 'go get'.
    40The vendor directory may be updated with 'go mod vendor'.
    41A typical sequence might be:
    42
    43    cd src
    44    go get -d golang.org/x/net@latest
    45    go mod tidy
    46    go mod vendor
    47
    48Use caution when passing '-u' to 'go get'. The '-u' flag updates
    49modules providing all transitively imported packages, not only
    50the module providing the target package.
    51
    52Note that 'go mod vendor' only copies packages that are transitively
    53imported by packages in the current module. If a new package is needed,
    54it should be imported before running 'go mod vendor'.

View as plain text