feat: remote taskfiles (HTTP) (#1152)

* feat: remote taskfiles over http

* feat: allow insecure connections when --insecure flag is provided

* feat: better error handling for fetch errors

* fix: ensure cache directory always exists

* fix: setup logger before everything else

* feat: put remote taskfiles behind an experiment

* feat: --download and --offline flags for remote taskfiles

* feat: node.Read accepts a context

* feat: experiment docs

* chore: changelog

* chore: remove unused optional param from Node interface

* chore: tidy up and generalise NewNode function

* fix: use sha256 in remote checksum

* feat: --download by itself will not run a task

* feat: custom error if remote taskfiles experiment is not enabled

* refactor: BaseNode functional options and simplified FileNode

* fix: use hex encoding for checksum instead of b64

errors/errors_taskfile.go

@@ -2,6 +2,7 @@ package errors
 
 import (
 	"fmt"
+	"net/http"
 )
 
 // TaskfileNotFoundError is returned when no appropriate Taskfile is found when
@@ -16,7 +17,7 @@ func (err TaskfileNotFoundError) Error() string {
 	if err.Walk {
 		walkText = " (or any of the parent directories)"
 	}
-	return fmt.Sprintf(`task: No Taskfile found at "%s"%s`, err.URI, walkText)
+	return fmt.Sprintf(`task: No Taskfile found at %q%s`, err.URI, walkText)
 }
 
 func (err TaskfileNotFoundError) Code() int {
@@ -49,3 +50,73 @@ func (err TaskfileInvalidError) Error() string {
 func (err TaskfileInvalidError) Code() int {
 	return CodeTaskfileInvalid
 }
+
+// TaskfileFetchFailedError is returned when no appropriate Taskfile is found when
+// searching the filesystem.
+type TaskfileFetchFailedError struct {
+	URI            string
+	HTTPStatusCode int
+}
+
+func (err TaskfileFetchFailedError) Error() string {
+	var statusText string
+	if err.HTTPStatusCode != 0 {
+		statusText = fmt.Sprintf(" with status code %d (%s)", err.HTTPStatusCode, http.StatusText(err.HTTPStatusCode))
+	}
+	return fmt.Sprintf(`task: Download of %q failed%s`, err.URI, statusText)
+}
+
+func (err TaskfileFetchFailedError) Code() int {
+	return CodeTaskfileFetchFailed
+}
+
+// TaskfileNotTrustedError is returned when the user does not accept the trust
+// prompt when downloading a remote Taskfile.
+type TaskfileNotTrustedError struct {
+	URI string
+}
+
+func (err *TaskfileNotTrustedError) Error() string {
+	return fmt.Sprintf(
+		`task: Taskfile %q not trusted by user`,
+		err.URI,
+	)
+}
+
+func (err *TaskfileNotTrustedError) Code() int {
+	return CodeTaskfileNotTrusted
+}
+
+// TaskfileNotSecureError is returned when the user attempts to download a
+// remote Taskfile over an insecure connection.
+type TaskfileNotSecureError struct {
+	URI string
+}
+
+func (err *TaskfileNotSecureError) Error() string {
+	return fmt.Sprintf(
+		`task: Taskfile %q cannot be downloaded over an insecure connection. You can override this by using the --insecure flag`,
+		err.URI,
+	)
+}
+
+func (err *TaskfileNotSecureError) Code() int {
+	return CodeTaskfileNotSecure
+}
+
+// TaskfileCacheNotFound is returned when the user attempts to use an offline
+// (cached) Taskfile but the files does not exist in the cache.
+type TaskfileCacheNotFound struct {
+	URI string
+}
+
+func (err *TaskfileCacheNotFound) Error() string {
+	return fmt.Sprintf(
+		`task: Taskfile %q was not found in the cache. Remove the --offline flag to use a remote copy or download it using the --download flag`,
+		err.URI,
+	)
+}
+
+func (err *TaskfileCacheNotFound) Code() int {
+	return CodeTaskfileCacheNotFound
+}