mirror of
https://github.com/zrepl/zrepl.git
synced 2024-12-22 15:11:16 +01:00
WIP PoC signalling
This commit is contained in:
parent
40be626b3a
commit
97a14dba90
@ -2,16 +2,19 @@ package client
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import (
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"context"
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"encoding/json"
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"fmt"
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"github.com/pkg/errors"
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"github.com/zrepl/zrepl/cli"
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"github.com/zrepl/zrepl/config"
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"github.com/zrepl/zrepl/daemon"
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"github.com/zrepl/zrepl/daemon/job"
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)
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var SignalCmd = &cli.Subcommand{
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Use: "signal [replication|reset|snapshot] JOB",
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Use: "signal JOB [replication|reset|snapshot]",
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Short: "run a job replication, abort its current invocation, run a snapshot job",
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Run: func(ctx context.Context, subcommand *cli.Subcommand, args []string) error {
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return runSignalCmd(subcommand.Config(), args)
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@ -28,15 +31,35 @@ func runSignalCmd(config *config.Config, args []string) error {
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return err
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}
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err = jsonRequestResponse(httpc, daemon.ControlJobEndpointSignal,
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jobName := args[0]
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what := args[1]
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var res job.ActiveSideSignalResponse
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err = jsonRequestResponse(httpc, daemon.ControlJobEndpointSignalActive,
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struct {
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Name string
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Op string
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Job string
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job.ActiveSideSignalRequest
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}{
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Name: args[1],
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Op: args[0],
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Job: jobName,
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ActiveSideSignalRequest: job.ActiveSideSignalRequest{
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What: what,
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},
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},
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struct{}{},
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&res,
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)
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pollRequest := daemon.ControlJobEndpointSignalActiveRequest{
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Job: jobName,
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ActiveSidePollRequest: job.ActiveSidePollRequest{
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InvocationId: res.InvocationId,
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What: what,
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},
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}
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j, err := json.Marshal(pollRequest)
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if err != nil {
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panic(err)
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}
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fmt.Println(string(j))
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return err
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}
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@ -11,6 +11,7 @@ import (
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"github.com/pkg/errors"
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"github.com/zrepl/zrepl/daemon"
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"github.com/zrepl/zrepl/daemon/job"
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)
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type Client struct {
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@ -42,14 +43,16 @@ func (c *Client) StatusRaw() ([]byte, error) {
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return r, nil
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}
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func (c *Client) signal(job, sig string) error {
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return jsonRequestResponse(c.h, daemon.ControlJobEndpointSignal,
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func (c *Client) signal(jobName, sig string) error {
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return jsonRequestResponse(c.h, daemon.ControlJobEndpointSignalActive,
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struct {
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Name string
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Op string
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Job string
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job.ActiveSideSignalRequest
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}{
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Name: job,
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Op: sig,
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Job: jobName,
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ActiveSideSignalRequest: job.ActiveSideSignalRequest{
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What: sig,
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},
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},
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struct{}{},
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)
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@ -2,6 +2,7 @@ package client
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import (
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"context"
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"encoding/json"
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"fmt"
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"strconv"
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"time"
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@ -17,12 +18,13 @@ import (
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)
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var waitCmdArgs struct {
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verbose bool
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verbose bool
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interval time.Duration
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token string
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}
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var WaitCmd = &cli.Subcommand{
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Use: "wait [active JOB INVOCATION_ID WHAT]",
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Use: "wait [-t TOKEN | [replication|snapshotting|prune_sender|prune_receiver JOB]]",
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Short: "",
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Run: func(ctx context.Context, subcommand *cli.Subcommand, args []string) error {
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return runWaitCmd(subcommand.Config(), args)
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@ -30,6 +32,7 @@ var WaitCmd = &cli.Subcommand{
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SetupFlags: func(f *pflag.FlagSet) {
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f.BoolVarP(&waitCmdArgs.verbose, "verbose", "v", false, "verbose output")
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f.DurationVarP(&waitCmdArgs.interval, "poll-interval", "i", 100*time.Millisecond, "poll interval")
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f.StringVarP(&waitCmdArgs.token, "token", "t", "", "token produced by 'signal' subcommand")
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},
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}
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@ -40,43 +43,50 @@ func runWaitCmd(config *config.Config, args []string) error {
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return err
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}
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if args[0] != "active" {
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panic(args)
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var pollRequest daemon.ControlJobEndpointSignalActiveRequest
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if waitCmdArgs.token != "" {
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if len(args) != 0 {
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return fmt.Errorf("-t and regular usage is mutually exclusive")
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}
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err := json.Unmarshal([]byte(waitCmdArgs.token), &pollRequest)
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if err != nil {
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return errors.Wrap(err, "cannot unmarshal token")
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}
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} else {
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if args[0] != "active" {
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panic(args)
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}
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args = args[1:]
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jobName := args[0]
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invocationId, err := strconv.ParseUint(args[1], 10, 64)
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if err != nil {
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return errors.Wrap(err, "parse invocation id")
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}
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waitWhat := args[2]
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// updated by subsequent requests
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pollRequest = daemon.ControlJobEndpointSignalActiveRequest{
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Job: jobName,
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ActiveSidePollRequest: job.ActiveSidePollRequest{
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InvocationId: invocationId,
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What: waitWhat,
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},
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}
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}
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args = args[1:]
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jobName := args[0]
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invocationId, err := strconv.ParseUint(args[1], 10, 64)
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if err != nil {
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return errors.Wrap(err, "parse invocation id")
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}
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waitWhat := args[2]
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doneErr := fmt.Errorf("done")
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var pollRequest job.ActiveSidePollRequest
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// updated by subsequent requests
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pollRequest = job.ActiveSidePollRequest{
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InvocationId: invocationId,
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What: waitWhat,
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}
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pollOnce := func() error {
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var res job.ActiveSidePollResponse
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if waitCmdArgs.verbose {
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pretty.Println("making poll request", pollRequest)
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}
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err = jsonRequestResponse(httpc, daemon.ControlJobEndpointPollActive,
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struct {
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Job string
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job.ActiveSidePollRequest
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}{
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Job: jobName,
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ActiveSidePollRequest: pollRequest,
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},
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pollRequest,
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&res,
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)
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if err != nil {
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@ -73,13 +73,18 @@ func (j *controlJob) RegisterMetrics(registerer prometheus.Registerer) {
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}
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const (
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ControlJobEndpointPProf string = "/debug/pprof"
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ControlJobEndpointVersion string = "/version"
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ControlJobEndpointStatus string = "/status"
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ControlJobEndpointSignal string = "/signal"
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ControlJobEndpointPollActive string = "/poll/active"
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ControlJobEndpointPProf string = "/debug/pprof"
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ControlJobEndpointVersion string = "/version"
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ControlJobEndpointStatus string = "/status"
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ControlJobEndpointSignalActive string = "/signal/active"
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ControlJobEndpointPollActive string = "/poll/active"
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)
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type ControlJobEndpointSignalActiveRequest struct {
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Job string
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job.ActiveSidePollRequest
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}
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func (j *controlJob) Run(ctx context.Context) {
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log := job.GetLogger(ctx)
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@ -132,11 +137,7 @@ func (j *controlJob) Run(ctx context.Context) {
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}})
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mux.Handle(ControlJobEndpointPollActive, requestLogger{log: log, handler: jsonRequestResponder{log, func(decoder jsonDecoder) (v interface{}, err error) {
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type reqT struct {
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Job string
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job.ActiveSidePollRequest
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}
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var req reqT
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var req ControlJobEndpointSignalActiveRequest
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if decoder(&req) != nil {
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return nil, errors.Errorf("decode failed")
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}
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@ -163,30 +164,40 @@ func (j *controlJob) Run(ctx context.Context) {
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return res, err
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}}})
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mux.Handle(ControlJobEndpointSignal,
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requestLogger{log: log, handler: jsonRequestResponder{log, func(decoder jsonDecoder) (interface{}, error) {
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mux.Handle(ControlJobEndpointSignalActive,
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requestLogger{log: log, handler: jsonRequestResponder{log, func(decoder jsonDecoder) (v interface{}, err error) {
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type reqT struct {
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Name string
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Op string
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Job string
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job.ActiveSideSignalRequest
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}
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var req reqT
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if decoder(&req) != nil {
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return nil, errors.Errorf("decode failed")
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}
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var err error
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switch req.Op {
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case "replication":
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err = j.jobs.doreplication(req.Name)
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case "reset":
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err = j.jobs.reset(req.Name)
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case "snapshot":
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err = j.jobs.dosnapshot(req.Name)
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default:
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err = fmt.Errorf("operation %q is invalid", req.Op)
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// FIXME dedup the following code with ControlJobEndpointPollActive
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j.jobs.m.RLock()
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jo, ok := j.jobs.jobs[req.Job]
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if !ok {
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j.jobs.m.RUnlock()
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return struct{}{}, fmt.Errorf("unknown job name %q", req.Job)
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}
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return struct{}{}, err
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ajo, ok := jo.(*job.ActiveSide)
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if !ok {
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v, err = struct{}{}, fmt.Errorf("job %q is not an active side (it's a %T)", jo.Name(), jo)
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j.jobs.m.RUnlock()
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return v, err
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}
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res, err := ajo.Signal(req.ActiveSideSignalRequest)
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j.jobs.m.RUnlock()
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return res, err
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}}})
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server := http.Server{
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@ -20,9 +20,6 @@ import (
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"github.com/zrepl/zrepl/config"
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"github.com/zrepl/zrepl/daemon/job"
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"github.com/zrepl/zrepl/daemon/job/doreplication"
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"github.com/zrepl/zrepl/daemon/job/dosnapshot"
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"github.com/zrepl/zrepl/daemon/job/reset"
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"github.com/zrepl/zrepl/daemon/logging"
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"github.com/zrepl/zrepl/logger"
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"github.com/zrepl/zrepl/version"
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@ -132,19 +129,13 @@ type jobs struct {
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wg sync.WaitGroup
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// m protects all fields below it
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m sync.RWMutex
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doreplications map[string]doreplication.Func // by Job.Name
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resets map[string]reset.Func // by Job.Name
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dosnapshots map[string]dosnapshot.Func // by Job.Name
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jobs map[string]job.Job
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m sync.RWMutex
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jobs map[string]job.Job
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}
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func newJobs() *jobs {
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return &jobs{
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doreplications: make(map[string]doreplication.Func),
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resets: make(map[string]reset.Func),
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dosnapshots: make(map[string]dosnapshot.Func),
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jobs: make(map[string]job.Job),
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jobs: make(map[string]job.Job),
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}
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}
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@ -193,39 +184,6 @@ func (s *jobs) status() map[string]*job.Status {
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return ret
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}
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func (s *jobs) doreplication(job string) error {
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s.m.RLock()
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defer s.m.RUnlock()
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wu, ok := s.doreplications[job]
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if !ok {
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return errors.Errorf("Job %s does not exist", job)
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}
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return wu()
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}
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func (s *jobs) reset(job string) error {
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s.m.RLock()
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defer s.m.RUnlock()
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wu, ok := s.resets[job]
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if !ok {
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return errors.Errorf("Job %s does not exist", job)
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}
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return wu()
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}
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func (s *jobs) dosnapshot(job string) error {
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s.m.RLock()
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defer s.m.RUnlock()
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wu, ok := s.dosnapshots[job]
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if !ok {
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return errors.Errorf("Job %s does not exist", job)
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}
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return wu()
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}
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const (
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jobNamePrometheus = "_prometheus"
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jobNameControl = "_control"
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@ -256,12 +214,6 @@ func (s *jobs) start(ctx context.Context, j job.Job, internal bool) {
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s.jobs[jobName] = j
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ctx = zfscmd.WithJobID(ctx, j.Name())
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ctx, doreplication := doreplication.Context(ctx)
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ctx, resetFunc := reset.Context(ctx)
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ctx, dosnapshotFunc := dosnapshot.Context(ctx)
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s.doreplications[jobName] = doreplication
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s.resets[jobName] = resetFunc
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s.dosnapshots[jobName] = dosnapshotFunc
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s.wg.Add(1)
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go func() {
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@ -14,7 +14,6 @@ import (
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"github.com/zrepl/zrepl/util/envconst"
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"github.com/zrepl/zrepl/config"
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"github.com/zrepl/zrepl/daemon/job/doreplication"
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"github.com/zrepl/zrepl/daemon/job/reset"
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"github.com/zrepl/zrepl/daemon/pruner"
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"github.com/zrepl/zrepl/daemon/snapper"
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@ -47,6 +46,7 @@ type ActiveSide struct {
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tasks activeSideTasks
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nextInvocationId uint64
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activeInvocationId uint64 // 0 <=> inactive
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signal chan struct{}
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}
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//go:generate enumer -type=ActiveSideState
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@ -65,6 +65,7 @@ type activeSideTasks struct {
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// valid for state ActiveSideReplicating, ActiveSidePruneSender, ActiveSidePruneReceiver, ActiveSideDone
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replicationReport driver.ReportFunc
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replicationCancel context.CancelFunc
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replicationDone *report.Report
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// valid for state ActiveSidePruneSender, ActiveSidePruneReceiver, ActiveSideDone
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prunerSender, prunerReceiver *pruner.Pruner
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@ -91,7 +92,7 @@ type activeMode interface {
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SenderReceiver() (logic.Sender, logic.Receiver)
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Type() Type
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PlannerPolicy() logic.PlannerPolicy
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RunPeriodic(ctx context.Context, replicationCommon chan<- struct{})
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RunPeriodic(ctx context.Context, wakePeriodic <-chan struct{}, replicationCommon chan<- struct{})
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SnapperReport() *snapper.Report
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ResetConnectBackoff()
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}
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@ -133,7 +134,7 @@ func (m *modePush) Type() Type { return TypePush }
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func (m *modePush) PlannerPolicy() logic.PlannerPolicy { return *m.plannerPolicy }
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func (m *modePush) RunPeriodic(ctx context.Context, replicationCommon chan<- struct{}) {
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func (m *modePush) RunPeriodic(ctx context.Context, wakePeriodic <-chan struct{}, replicationCommon chan<- struct{}) {
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m.snapper.Run(ctx, replicationCommon)
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}
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@ -216,7 +217,7 @@ func (*modePull) Type() Type { return TypePull }
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func (m *modePull) PlannerPolicy() logic.PlannerPolicy { return *m.plannerPolicy }
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func (m *modePull) RunPeriodic(ctx context.Context, replicationCommon chan<- struct{}) {
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func (m *modePull) RunPeriodic(ctx context.Context, wakePeriodic <-chan struct{}, replicationCommon chan<- struct{}) {
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if m.interval.Manual {
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GetLogger(ctx).Info("manual pull configured, periodic pull disabled")
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// "waiting for wakeup replications" is printed in common ActiveSide.do
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@ -432,8 +433,11 @@ func (j *ActiveSide) Run(ctx context.Context) {
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defer cancel()
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periodicCtx, endTask := trace.WithTask(ctx, "periodic")
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defer endTask()
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go j.mode.RunPeriodic(periodicCtx, periodicDone)
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wakePeriodic := make(chan struct{})
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go j.mode.RunPeriodic(periodicCtx, wakePeriodic, periodicDone)
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j.signal = make(chan struct{})
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j.nextInvocationId = 1
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outer:
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@ -444,7 +448,7 @@ outer:
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log.WithError(ctx.Err()).Info("context")
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break outer
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case <-doreplication.Wait(ctx):
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case <-j.signal:
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j.mode.ResetConnectBackoff()
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case <-periodicDone:
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}
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@ -490,7 +494,7 @@ func (j *ActiveSide) Poll(req ActiveSidePollRequest) (*ActiveSidePollResponse, e
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}
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switch req.What {
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case "invocation-done":
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case "invocation":
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var done bool
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if j.activeInvocationId == 0 {
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done = waitForId < j.nextInvocationId
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@ -504,6 +508,47 @@ func (j *ActiveSide) Poll(req ActiveSidePollRequest) (*ActiveSidePollResponse, e
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}
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}
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type ActiveSideSignalRequest struct {
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What string
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}
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type ActiveSideSignalResponse struct {
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InvocationId uint64
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}
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func (j *ActiveSide) Signal(req ActiveSideSignalRequest) (*ActiveSideSignalResponse, error) {
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// switch req.What {
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// case "replication":
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// invocationId, err = j.jobs.doreplication(req.Name)
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// case "reset":
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// err = j.jobs.reset(req.Name)
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// case "snapshot":
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// err = j.jobs.dosnapshot(req.Name)
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// default:
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// err = fmt.Errorf("operation %q is invalid", req.Op)
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// }
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|
||||
switch req.What {
|
||||
case "invocation":
|
||||
j.tasksMtx.Lock()
|
||||
var invocationId uint64
|
||||
if j.activeInvocationId != 0 {
|
||||
invocationId = j.activeInvocationId
|
||||
} else {
|
||||
invocationId = j.nextInvocationId
|
||||
}
|
||||
// non-blocking send (.Run() must not hold mutex while waiting for signals)
|
||||
select {
|
||||
case j.signal <- struct{}{}:
|
||||
default:
|
||||
}
|
||||
j.tasksMtx.Unlock()
|
||||
return &ActiveSideSignalResponse{InvocationId: invocationId}, nil
|
||||
default:
|
||||
return nil, fmt.Errorf("unknown signal %q", req.What)
|
||||
}
|
||||
}
|
||||
|
||||
func (j *ActiveSide) do(ctx context.Context) {
|
||||
|
||||
j.mode.ConnectEndpoints(ctx, j.connecter)
|
||||
@ -546,7 +591,9 @@ func (j *ActiveSide) do(ctx context.Context) {
|
||||
repCancel() // always cancel to free up context resources
|
||||
replicationReport := j.tasks.replicationReport()
|
||||
j.promReplicationErrors.Set(float64(replicationReport.GetFailedFilesystemsCountInLatestAttempt()))
|
||||
|
||||
j.updateTasks(func(tasks *activeSideTasks) {
|
||||
tasks.replicationDone = replicationReport
|
||||
})
|
||||
endSpan()
|
||||
}
|
||||
|
||||
|
@ -1,35 +0,0 @@
|
||||
package doreplication
|
||||
|
||||
import (
|
||||
"context"
|
||||
"errors"
|
||||
)
|
||||
|
||||
type contextKey int
|
||||
|
||||
const contextKeyReplication contextKey = iota
|
||||
|
||||
func Wait(ctx context.Context) <-chan struct{} {
|
||||
wc, ok := ctx.Value(contextKeyReplication).(chan struct{})
|
||||
if !ok {
|
||||
wc = make(chan struct{})
|
||||
}
|
||||
return wc
|
||||
}
|
||||
|
||||
type Func func() error
|
||||
|
||||
var AlreadyReplicating = errors.New("already replicating")
|
||||
|
||||
func Context(ctx context.Context) (context.Context, Func) {
|
||||
wc := make(chan struct{})
|
||||
wuf := func() error {
|
||||
select {
|
||||
case wc <- struct{}{}:
|
||||
return nil
|
||||
default:
|
||||
return AlreadyReplicating
|
||||
}
|
||||
}
|
||||
return context.WithValue(ctx, contextKeyReplication, wc), wuf
|
||||
}
|
@ -1,35 +0,0 @@
|
||||
package dosnapshot
|
||||
|
||||
import (
|
||||
"context"
|
||||
"errors"
|
||||
)
|
||||
|
||||
type contextKey int
|
||||
|
||||
const contextKeyDosnapshot contextKey = iota
|
||||
|
||||
func Wait(ctx context.Context) <-chan struct{} {
|
||||
wc, ok := ctx.Value(contextKeyDosnapshot).(chan struct{})
|
||||
if !ok {
|
||||
wc = make(chan struct{})
|
||||
}
|
||||
return wc
|
||||
}
|
||||
|
||||
type Func func() error
|
||||
|
||||
var AlreadyDosnapshot = errors.New("already snapshotting")
|
||||
|
||||
func Context(ctx context.Context) (context.Context, Func) {
|
||||
wc := make(chan struct{})
|
||||
wuf := func() error {
|
||||
select {
|
||||
case wc <- struct{}{}:
|
||||
return nil
|
||||
default:
|
||||
return AlreadyDosnapshot
|
||||
}
|
||||
}
|
||||
return context.WithValue(ctx, contextKeyDosnapshot, wc), wuf
|
||||
}
|
@ -1,35 +0,0 @@
|
||||
package reset
|
||||
|
||||
import (
|
||||
"context"
|
||||
"errors"
|
||||
)
|
||||
|
||||
type contextKey int
|
||||
|
||||
const contextKeyReset contextKey = iota
|
||||
|
||||
func Wait(ctx context.Context) <-chan struct{} {
|
||||
wc, ok := ctx.Value(contextKeyReset).(chan struct{})
|
||||
if !ok {
|
||||
wc = make(chan struct{})
|
||||
}
|
||||
return wc
|
||||
}
|
||||
|
||||
type Func func() error
|
||||
|
||||
var AlreadyReset = errors.New("already reset")
|
||||
|
||||
func Context(ctx context.Context) (context.Context, Func) {
|
||||
wc := make(chan struct{})
|
||||
wuf := func() error {
|
||||
select {
|
||||
case wc <- struct{}{}:
|
||||
return nil
|
||||
default:
|
||||
return AlreadyReset
|
||||
}
|
||||
}
|
||||
return context.WithValue(ctx, contextKeyReset, wc), wuf
|
||||
}
|
Loading…
Reference in New Issue
Block a user