1 files changed, 268 insertions, 0 deletions
diff --git a/poky/bitbake/lib/bb/fetch2/gomod.py b/poky/bitbake/lib/bb/fetch2/gomod.py
new file mode 100644
index 0000000000..21fbe80f56
--- /dev/null
+++ b/poky/bitbake/lib/bb/fetch2/gomod.py
@@ -0,0 +1,268 @@
+"""
+BitBake 'Fetch' implementation for Go modules
+
+The gomod/gomodgit fetchers are used to download Go modules to the module cache
+from a module proxy or directly from a version control repository.
+
+Example SRC_URI:
+
+SRC_URI += "gomod://golang.org/x/net;version=v0.9.0;sha256sum=..."
+SRC_URI += "gomodgit://golang.org/x/net;version=v0.9.0;repo=go.googlesource.com/net;srcrev=..."
+
+Required SRC_URI parameters:
+
+- version
+    The version of the module.
+
+Optional SRC_URI parameters:
+
+- mod
+    Fetch and unpack the go.mod file only instead of the complete module.
+    The go command may need to download go.mod files for many different modules
+    when computing the build list, and go.mod files are much smaller than
+    module zip files.
+    The default is "0", set mod=1 for the go.mod file only.
+
+- sha256sum
+    The checksum of the module zip file, or the go.mod file in case of fetching
+    only the go.mod file. Alternatively, set the SRC_URI varible flag for
+    "module@version.sha256sum".
+
+- protocol
+    The method used when fetching directly from a version control repository.
+    The default is "https" for git.
+
+- repo
+    The URL when fetching directly from a version control repository. Required
+    when the URL is different from the module path.
+
+- srcrev
+    The revision identifier used when fetching directly from a version control
+    repository. Alternatively, set the SRCREV varible for "module@version".
+
+- subdir
+    The module subdirectory when fetching directly from a version control
+    repository. Required when the module is not located in the root of the
+    repository.
+
+Related variables:
+
+- GO_MOD_PROXY
+    The module proxy used by the fetcher.
+
+- GO_MOD_CACHE_DIR
+    The directory where the module cache is located.
+    This must match the exported GOMODCACHE variable for the go command to find
+    the downloaded modules.
+
+See the Go modules reference, https://go.dev/ref/mod, for more information
+about the module cache, module proxies and version control systems.
+"""
+
+import hashlib
+import os
+import re
+import shutil
+import subprocess
+import zipfile
+
+import bb
+from bb.fetch2 import FetchError
+from bb.fetch2 import MissingParameterError
+from bb.fetch2 import runfetchcmd
+from bb.fetch2 import subprocess_setup
+from bb.fetch2.git import Git
+from bb.fetch2.wget import Wget
+
+
+def escape(path):
+    """Escape capital letters using exclamation points."""
+    return re.sub(r'([A-Z])', lambda m: '!' + m.group(1).lower(), path)
+
+
+class GoMod(Wget):
+    """Class to fetch Go modules from a Go module proxy via wget"""
+
+    def supports(self, ud, d):
+        """Check to see if a given URL is for this fetcher."""
+        return ud.type == 'gomod'
+
+    def urldata_init(self, ud, d):
+        """Set up to download the module from the module proxy.
+
+        Set up to download the module zip file to the module cache directory
+        and unpack the go.mod file (unless downloading only the go.mod file):
+
+        cache/download/<module>/@v/<version>.zip: The module zip file.
+        cache/download/<module>/@v/<version>.mod: The go.mod file.
+        """
+
+        proxy = d.getVar('GO_MOD_PROXY') or 'proxy.golang.org'
+        moddir = d.getVar('GO_MOD_CACHE_DIR') or 'pkg/mod'
+
+        if 'version' not in ud.parm:
+            raise MissingParameterError('version', ud.url)
+
+        module = ud.host
+        if ud.path != '/':
+            module += ud.path
+        ud.parm['module'] = module
+
+        # Set URL and filename for wget download
+        path = escape(module + '/@v/' + ud.parm['version'])
+        if ud.parm.get('mod', '0') == '1':
+            path += '.mod'
+        else:
+            path += '.zip'
+            ud.parm['unpack'] = '0'
+        ud.url = bb.fetch2.encodeurl(
+            ('https', proxy, '/' + path, None, None, None))
+        ud.parm['downloadfilename'] = path
+
+        # Set name parameter if sha256sum is set in recipe
+        name = f"{module}@{ud.parm['version']}"
+        if d.getVarFlag('SRC_URI', name + '.sha256sum'):
+            ud.parm['name'] = name
+
+        # Set subdir for unpack
+        ud.parm['subdir'] = os.path.join(moddir, 'cache/download',
+                                         os.path.dirname(path))
+
+        super().urldata_init(ud, d)
+
+    def unpack(self, ud, rootdir, d):
+        """Unpack the module in the module cache."""
+
+        # Unpack the module zip file or go.mod file
+        super().unpack(ud, rootdir, d)
+
+        if ud.localpath.endswith('.zip'):
+            # Unpack the go.mod file from the zip file
+            module = ud.parm['module']
+            unpackdir = os.path.join(rootdir, ud.parm['subdir'])
+            name = os.path.basename(ud.localpath).rsplit('.', 1)[0] + '.mod'
+            bb.note(f"Unpacking {name} to {unpackdir}/")
+            with zipfile.ZipFile(ud.localpath) as zf:
+                with open(os.path.join(unpackdir, name), mode='wb') as mf:
+                    try:
+                        f = module + '@' + ud.parm['version'] + '/go.mod'
+                        shutil.copyfileobj(zf.open(f), mf)
+                    except KeyError:
+                        # If the module does not have a go.mod file, synthesize
+                        # one containing only a module statement.
+                        mf.write(f'module {module}\n'.encode())
+
+
+class GoModGit(Git):
+    """Class to fetch Go modules directly from a git repository"""
+
+    def supports(self, ud, d):
+        """Check to see if a given URL is for this fetcher."""
+        return ud.type == 'gomodgit'
+
+    def urldata_init(self, ud, d):
+        """Set up to download the module from the git repository.
+
+        Set up to download the git repository to the module cache directory and
+        unpack the module zip file and the go.mod file:
+
+        cache/vcs/<hash>:                         The bare git repository.
+        cache/download/<module>/@v/<version>.zip: The module zip file.
+        cache/download/<module>/@v/<version>.mod: The go.mod file.
+        """
+
+        moddir = d.getVar('GO_MOD_CACHE_DIR') or 'pkg/mod'
+
+        if 'version' not in ud.parm:
+            raise MissingParameterError('version', ud.url)
+
+        module = ud.host
+        if ud.path != '/':
+            module += ud.path
+        ud.parm['module'] = module
+
+        # Set host, path and srcrev for git download
+        if 'repo' in ud.parm:
+            repo = ud.parm['repo']
+            idx = repo.find('/')
+            if idx != -1:
+                ud.host = repo[:idx]
+                ud.path = repo[idx:]
+            else:
+                ud.host = repo
+                ud.path = ''
+        if 'protocol' not in ud.parm:
+            ud.parm['protocol'] = 'https'
+        name = f"{module}@{ud.parm['version']}"
+        ud.names = [name]
+        srcrev = d.getVar('SRCREV_' + name)
+        if srcrev:
+            if 'srcrev' not in ud.parm:
+                ud.parm['srcrev'] = srcrev
+        else:
+            if 'srcrev' in ud.parm:
+                d.setVar('SRCREV_' + name, ud.parm['srcrev'])
+        if 'branch' not in ud.parm:
+            ud.parm['nobranch'] = '1'
+
+        # Set subpath, subdir and bareclone for git unpack
+        if 'subdir' in ud.parm:
+            ud.parm['subpath'] = ud.parm['subdir']
+        key = f"git3:{ud.parm['protocol']}://{ud.host}{ud.path}".encode()
+        ud.parm['key'] = key
+        ud.parm['subdir'] = os.path.join(moddir, 'cache/vcs',
+                                         hashlib.sha256(key).hexdigest())
+        ud.parm['bareclone'] = '1'
+
+        super().urldata_init(ud, d)
+
+    def unpack(self, ud, rootdir, d):
+        """Unpack the module in the module cache."""
+
+        # Unpack the bare git repository
+        super().unpack(ud, rootdir, d)
+
+        moddir = d.getVar('GO_MOD_CACHE_DIR') or 'pkg/mod'
+
+        # Create the info file
+        module = ud.parm['module']
+        repodir = os.path.join(rootdir, ud.parm['subdir'])
+        with open(repodir + '.info', 'wb') as f:
+            f.write(ud.parm['key'])
+
+        # Unpack the go.mod file from the repository
+        unpackdir = os.path.join(rootdir, moddir, 'cache/download',
+                                 escape(module), '@v')
+        bb.utils.mkdirhier(unpackdir)
+        srcrev = ud.parm['srcrev']
+        version = ud.parm['version']
+        escaped_version = escape(version)
+        cmd = f"git ls-tree -r --name-only '{srcrev}'"
+        if 'subpath' in ud.parm:
+            cmd += f" '{ud.parm['subpath']}'"
+        files = runfetchcmd(cmd, d, workdir=repodir).split()
+        name = escaped_version + '.mod'
+        bb.note(f"Unpacking {name} to {unpackdir}/")
+        with open(os.path.join(unpackdir, name), mode='wb') as mf:
+            f = 'go.mod'
+            if 'subpath' in ud.parm:
+                f = os.path.join(ud.parm['subpath'], f)
+            if f in files:
+                cmd = ['git', 'cat-file', 'blob', srcrev + ':' + f]
+                subprocess.check_call(cmd, stdout=mf, cwd=repodir,
+                                      preexec_fn=subprocess_setup)
+            else:
+                # If the module does not have a go.mod file, synthesize one
+                # containing only a module statement.
+                mf.write(f'module {module}\n'.encode())
+
+        # Synthesize the module zip file from the repository
+        name = escaped_version + '.zip'
+        bb.note(f"Unpacking {name} to {unpackdir}/")
+        with zipfile.ZipFile(os.path.join(unpackdir, name), mode='w') as zf:
+            prefix = module + '@' + version + '/'
+            for f in files:
+                cmd = ['git', 'cat-file', 'blob', srcrev + ':' + f]
+                data = subprocess.check_output(cmd, cwd=repodir,
+                                               preexec_fn=subprocess_setup)
+                zf.writestr(prefix + f, data)