nwaku/waku/waku_keystore/utils.nim

82 lines
2.4 KiB
Nim

{.push raises: [].}
import json, std/[os, sequtils]
import ./keyfile, ./protocol_types
# Checks if a JsonNode has all keys contained in "keys"
proc hasKeys*(data: JsonNode, keys: openArray[string]): bool =
return all(
keys,
proc(key: string): bool =
return data.hasKey(key),
)
# Safely saves a Keystore's JsonNode to disk.
# If exists, the destination file is renamed with extension .bkp; the file is written at its destination and the .bkp file is removed if write is successful, otherwise is restored
proc save*(json: JsonNode, path: string, separator: string): KeystoreResult[void] =
# We first backup the current keystore
if fileExists(path):
try:
moveFile(path, path & ".bkp")
except: # TODO: Fix "BareExcept" warning
return err(
AppKeystoreError(
kind: KeystoreOsError,
msg: "could not backup keystore: " & getCurrentExceptionMsg(),
)
)
# We save the updated json
var f: File
if not f.open(path, fmAppend):
return err(
AppKeystoreError(
kind: KeystoreOsError,
msg: "error in waku_keystore save: " & getCurrentExceptionMsg(),
)
)
try:
# To avoid other users/attackers to be able to read keyfiles, we make the file readable/writable only by the running user
setFilePermissions(path, {fpUserWrite, fpUserRead})
f.write($json)
# We store a keyfile per line
f.write(separator)
except CatchableError:
# We got some KeystoreOsError writing to disk. We attempt to restore the previous keystore backup
if fileExists(path & ".bkp"):
try:
f.close()
removeFile(path)
moveFile(path & ".bkp", path)
except: # TODO: Fix "BareExcept" warning
# Unlucky, we just fail
return err(
AppKeystoreError(
kind: KeystoreOsError,
msg: "could not restore keystore backup: " & getCurrentExceptionMsg(),
)
)
return err(
AppKeystoreError(
kind: KeystoreOsError,
msg: "could not write keystore: " & getCurrentExceptionMsg(),
)
)
finally:
f.close()
# The write went fine, so we can remove the backup keystore
if fileExists(path & ".bkp"):
try:
removeFile(path & ".bkp")
except CatchableError:
return err(
AppKeystoreError(
kind: KeystoreOsError,
msg: "could not remove keystore backup: " & getCurrentExceptionMsg(),
)
)
return ok()