// Determines if either there is no currently built version of the agent,
// or if the currently built version is out of date.
// Returns whether a new version needs to be built, and an error if any
// of the checks within the function throw an error.
func (self *AgentBasedHostGateway) AgentNeedsBuild() (bool, error) {
// compute and cache the current hash of the agent package
agentHash, err := util.CurrentGitHash(self.AgentPackageDir)
if err != nil {
return false, fmt.Errorf("error getting git hash of agent package "+
"at %v: %v", self.AgentPackageDir, err)
}
self.currentAgentHash = agentHash
// if the local directory where the executables live does not exist, then we
// certainly need to build the agent
exists, err := util.FileExists(self.ExecutablesDir)
if err != nil {
return false, err
}
if !exists {
return true, nil
}
// if the most recently built agent hash is different from the current
// mci hash, then the agent needs to be rebuilt
lastBuiltRevision, err := db.GetLastAgentBuild()
if err != nil {
return false, fmt.Errorf("error getting last agent build hash: %v", err)
}
return self.currentAgentHash != lastBuiltRevision, nil
}
func TestAgentBasedHostGateway(t *testing.T) {
var hostGateway *AgentBasedHostGateway
SkipConvey("When checking if the agent needs to be built", t, func() {
hostGateway = &AgentBasedHostGateway{}
Convey("a non-existent executables directory should cause the agent"+
" to need to be built", func() {
hostGateway.ExecutablesDir = "/foo/bar/baz/foo/bar"
needsBuild, err := hostGateway.AgentNeedsBuild()
So(err, ShouldBeNil)
So(needsBuild, ShouldBeTrue)
})
Convey("an out-of-date last-built version of the agent should cause"+
" the agent to need to be built", func() {
hostGateway.ExecutablesDir = "/" // just needs to exist
// store the "last built hash" as something different than the
// current one
So(db.StoreLastAgentBuild("fedcba"), ShouldBeNil)
needsBuild, err := hostGateway.AgentNeedsBuild()
So(err, ShouldBeNil)
So(needsBuild, ShouldBeTrue)
})
Convey("an up-to-date last-built version of the agent should cause"+
" the agent to not need to be built", func() {
hostGateway.ExecutablesDir = "/" // just needs to exist
// compute and cache the current hash of the agent package
agentHash, err := util.CurrentGitHash(hostGateway.AgentPackageDir)
So(err, ShouldBeNil)
// store the "last built hash" as the same as the current one
So(db.StoreLastAgentBuild(agentHash), ShouldBeNil)
needsBuild, err := hostGateway.AgentNeedsBuild()
So(err, ShouldBeNil)
So(needsBuild, ShouldBeFalse)
})
})
SkipConvey("When building the agent", t, func() {
hostGateway = &AgentBasedHostGateway{}
So(db.StoreLastAgentBuild("abcdef"), ShouldBeNil)
Convey("a nil AgentCompiler should cause a panic", func() {
So(func() { hostGateway.buildAgent() }, ShouldPanic)
})
Convey("a failed compilation should error and cause the build to not"+
" be recorded as successful", func() {
// attempt to compile
hostGateway.currentAgentHash = "fedcba"
hostGateway.Compiler = &FailingAgentCompiler{}
So(hostGateway.buildAgent(), ShouldNotBeNil)
// make sure the last built hash was not updated
lastBuiltHash, err := db.GetLastAgentBuild()
So(err, ShouldBeNil)
So(lastBuiltHash, ShouldEqual, "abcdef")
})
Convey("a successful compilation should cause the build to be"+
" recorded as successful", func() {
// attempt to compile
hostGateway.currentAgentHash = "fedcba"
hostGateway.Compiler = &SucceedingAgentCompiler{}
So(hostGateway.buildAgent(), ShouldBeNil)
// make sure the last built hash was updated
lastBuiltHash, err := db.GetLastAgentBuild()
So(err, ShouldBeNil)
So(lastBuiltHash, ShouldEqual, "fedcba")
})
})
Convey("When prepping the remote machine", t, func() {
Convey("the remote shell should be created, and the config directory"+
" and agent binaries should be copied over to it", func() {
hostGateway = &AgentBasedHostGateway{
Compiler: &SucceedingAgentCompiler{},
}
// create a mock config directory, mock executables
// directory, and mock remote shell
evgHome := evergreen.FindEvergreenHome()
tmpBase := filepath.Join(evgHome, "taskrunner/testdata/tmp")
mockConfigDir := filepath.Join(tmpBase, "mock_config_dir")
hostGatewayTestConf.ConfigDir = mockConfigDir
mockExecutablesDir := filepath.Join(tmpBase, "mock_executables_dir")
hostGateway.ExecutablesDir = mockExecutablesDir
mockExecutable := filepath.Join(mockExecutablesDir, "main")
mockRemoteShell := filepath.Join(tmpBase, "mock_remote_shell")
evergreen.RemoteShell = mockRemoteShell
// prevent permissions issues
syscall.Umask(0000)
// remove the directories, if they exist (start clean)
exists, err := util.FileExists(tmpBase)
So(err, ShouldBeNil)
if exists {
So(os.RemoveAll(tmpBase), ShouldBeNil)
}
So(os.MkdirAll(tmpBase, 0777), ShouldBeNil)
// create the config and executables directories, as well as a
// mock executable, to copy over
So(os.Mkdir(mockConfigDir, 0777), ShouldBeNil)
So(os.Mkdir(mockExecutablesDir, 0777), ShouldBeNil)
So(ioutil.WriteFile(mockExecutable, []byte("run me"), 0777),
ShouldBeNil)
// mock up a host for localhost
localhost := host.Host{
Host: command.TestRemote,
User: command.TestRemoteUser,
}
// prep the "remote" host
_, err = hostGateway.prepRemoteHost(hostGatewayTestConf,
localhost, []string{"-i", command.TestRemoteKey}, "")
So(err, ShouldBeNil)
// make sure the correct files were created and copied over
exists, err = util.FileExists(filepath.Join(mockRemoteShell,
"mock_config_dir"))
So(err, ShouldBeNil)
So(exists, ShouldBeTrue)
exists, err = util.FileExists(filepath.Join(mockRemoteShell,
"main"))
So(err, ShouldBeNil)
So(exists, ShouldBeTrue)
})
})
}