import json import logging import os import subprocess import sys import tempfile from typing import Any, Callable, Dict, List, Optional, Sequence, Tuple, Type, Union from python_terraform.tfstate import Tfstate logger = logging.getLogger(__name__) COMMAND_WITH_SUBCOMMANDS = {"workspace"} class TerraformFlag: pass class IsFlagged(TerraformFlag): pass class IsNotFlagged(TerraformFlag): pass CommandOutput = Tuple[Optional[int], Optional[str], Optional[str]] class TerraformCommandError(subprocess.CalledProcessError): def __init__(self, ret_code: int, cmd: str, out: Optional[str], err: Optional[str]): super(TerraformCommandError, self).__init__(ret_code, cmd) self.out = out self.err = err logger.error("Error with command %s. Reason: %s", self.cmd, self.err) class Terraform: """Wrapper of terraform command line tool. https://www.terraform.io/ """ def __init__( self, working_dir: Optional[str] = None, targets: Optional[Sequence[str]] = None, state: Optional[str] = None, variables: Optional[Dict[str, str]] = None, parallelism: Optional[str] = None, var_file: Optional[str] = None, terraform_bin_path: Optional[str] = None, is_env_vars_included: bool = True, terraform_version: Optional[float] = 0.13 ): """ :param working_dir: the folder of the working folder, if not given, will be current working folder :param targets: list of target as default value of apply/destroy/plan command :param state: path of state file relative to working folder, as a default value of apply/destroy/plan command :param variables: default variables for apply/destroy/plan command, will be override by variable passing by apply/destroy/plan method :param parallelism: default parallelism value for apply/destroy command :param var_file: passed as value of -var-file option, could be string or list, list stands for multiple -var-file option :param terraform_bin_path: binary path of terraform :type is_env_vars_included: bool :param is_env_vars_included: included env variables when calling terraform cmd """ self.is_env_vars_included = is_env_vars_included self.working_dir = working_dir self.state = state self.targets = [] if targets is None else targets self.variables = dict() if variables is None else variables self.parallelism = parallelism self.terraform_bin_path = ( terraform_bin_path if terraform_bin_path else "terraform" ) self.terraform_version = terraform_version self.var_file = var_file self.temp_var_files = VariableFiles() # store the tfstate data self.tfstate = None self.read_state_file(self.state) self.latest_cmd = '' def apply( self, dir_or_plan: Optional[str] = None, input: bool = False, skip_plan: bool = True, no_color: Type[TerraformFlag] = IsFlagged, **kwargs, ) -> CommandOutput: """Refer to https://terraform.io/docs/commands/apply.html no-color is flagged by default :param no_color: disable color of stdout :param input: disable prompt for a missing variable :param dir_or_plan: folder relative to working folder :param skip_plan: force apply without plan (default: false) :param kwargs: same as kwags in method 'cmd' :returns return_code, stdout, stderr """ if not skip_plan: return self.plan(dir_or_plan=dir_or_plan, **kwargs) global_opts = self._generate_default_general_options(dir_or_plan) default = kwargs.copy() default["input"] = input default["no_color"] = no_color default["auto-approve"] = True # a False value will require an input option_dict = self._generate_default_options(default) args = self._generate_default_args(dir_or_plan) return self.cmd(global_opts, "apply", *args, **option_dict) def refresh( self, dir_or_plan: Optional[str] = None, input: bool = False, no_color: Type[TerraformFlag] = IsFlagged, **kwargs, ) -> CommandOutput: """Refer to https://terraform.io/docs/commands/refresh.html no-color is flagged by default :param no_color: disable color of stdout :param input: disable prompt for a missing variable :param dir_or_plan: folder relative to working folder :param kwargs: same as kwags in method 'cmd' :returns return_code, stdout, stderr """ global_opts = self._generate_default_general_options(dir_or_plan) default = kwargs.copy() default["input"] = input default["no_color"] = no_color option_dict = self._generate_default_options(default) args = self._generate_default_args(dir_or_plan) return self.cmd(global_opts, "refresh", *args, **option_dict) def destroy( self, dir_or_plan: Optional[str] = None, force: Type[TerraformFlag] = IsFlagged, **kwargs, ) -> CommandOutput: """Refer to https://www.terraform.io/docs/commands/destroy.html force/no-color option is flagged by default :return: ret_code, stdout, stderr """ global_opts = self._generate_default_general_options(dir_or_plan) default = kwargs.copy() default["force"] = force options = self._generate_default_options(default) args = self._generate_default_args(dir_or_plan) return self.cmd(global_opts, "destroy", *args, **options) def plan( self, dir_or_plan: Optional[str] = None, detailed_exitcode: Type[TerraformFlag] = IsFlagged, **kwargs, ) -> CommandOutput: """Refer to https://www.terraform.io/docs/commands/plan.html :param detailed_exitcode: Return a detailed exit code when the command exits. :param dir_or_plan: relative path to plan/folder :param kwargs: options :return: ret_code, stdout, stderr """ global_opts = self._generate_default_general_options(dir_or_plan) options = kwargs.copy() options["detailed_exitcode"] = detailed_exitcode options = self._generate_default_options(options) args = self._generate_default_args(dir_or_plan) return self.cmd(global_opts, "plan", *args, **options) def init( self, dir_or_plan: Optional[str] = None, backend_config: Optional[Dict[str, str]] = None, reconfigure: Type[TerraformFlag] = IsFlagged, backend: bool = True, **kwargs, ) -> CommandOutput: """Refer to https://www.terraform.io/docs/commands/init.html By default, this assumes you want to use backend config, and tries to init fresh. The flags -reconfigure and -backend=true are default. :param dir_or_plan: relative path to the folder want to init :param backend_config: a dictionary of backend config options. eg. t = Terraform() t.init(backend_config={'access_key': 'myaccesskey', 'secret_key': 'mysecretkey', 'bucket': 'mybucketname'}) :param reconfigure: whether or not to force reconfiguration of backend :param backend: whether or not to use backend settings for init :param kwargs: options :return: ret_code, stdout, stderr """ options = kwargs.copy() options.update( { "backend_config": backend_config, "reconfigure": reconfigure, "backend": backend, } ) options = self._generate_default_options(options) global_opts = self._generate_default_general_options(dir_or_plan) args = self._generate_default_args(dir_or_plan) return self.cmd(global_opts, "init", *args, **options) def generate_cmd_string(self, global_options: Dict[str, Any], cmd: str, *args, **kwargs) -> List[str]: """For any generate_cmd_string doesn't written as public method of Terraform examples: 1. call import command, ref to https://www.terraform.io/docs/commands/import.html --> generate_cmd_string call: terraform import -input=true aws_instance.foo i-abcd1234 --> python call: tf.generate_cmd_string('import', 'aws_instance.foo', 'i-abcd1234', input=True) 2. call apply command, --> generate_cmd_string call: terraform apply -var='a=b' -var='c=d' -no-color the_folder --> python call: tf.generate_cmd_string('apply', the_folder, no_color=IsFlagged, var={'a':'b', 'c':'d'}) :param cmd: command and sub-command of terraform, seperated with space refer to https://www.terraform.io/docs/commands/index.html :param args: arguments of a command :param kwargs: same as kwags in method 'cmd' :return: string of valid terraform command """ cmds = [self.terraform_bin_path] cmds += self._generate_cmd_options(**global_options) cmds += cmd.split() if cmd in COMMAND_WITH_SUBCOMMANDS: args = list(args) subcommand = args.pop(0) cmds.append(subcommand) cmds += self._generate_cmd_options(**kwargs) cmds += args self.latest_cmd = ' '.join(cmds) return cmds def cmd( self, global_opts: Dict[str, Any], cmd: str, *args, capture_output: Union[bool, str] = True, raise_on_error: bool = True, synchronous: bool = True, **kwargs, ) -> CommandOutput: """Run a terraform command, if success, will try to read state file :param cmd: command and sub-command of terraform, seperated with space refer to https://www.terraform.io/docs/commands/index.html :param args: arguments of a command :param kwargs: any option flag with key value without prefixed dash character if there's a dash in the option name, use under line instead of dash, ex. -no-color --> no_color if it's a simple flag with no value, value should be IsFlagged ex. cmd('taint', allow＿missing=IsFlagged) if it's a boolean value flag, assign True or false if it's a flag could be used multiple times, assign list to it's value if it's a "var" variable flag, assign dictionary to it if a value is None, will skip this option if the option 'capture_output' is passed (with any value other than True), terraform output will be printed to stdout/stderr and "None" will be returned as out and err. if the option 'raise_on_error' is passed (with any value that evaluates to True), and the terraform command returns a nonzerop return code, then a TerraformCommandError exception will be raised. The exception object will have the following properties: returncode: The command's return code out: The captured stdout, or None if not captured err: The captured stderr, or None if not captured :return: ret_code, out, err """ if capture_output is True: stderr = subprocess.PIPE stdout = subprocess.PIPE elif capture_output == "framework": stderr = None stdout = None else: stderr = sys.stderr stdout = sys.stdout cmds = self.generate_cmd_string(global_opts, cmd, *args, **kwargs) logger.info("Command: %s", " ".join(cmds)) working_folder = self.working_dir if self.working_dir else None environ_vars = {} if self.is_env_vars_included: environ_vars = os.environ.copy() p = subprocess.Popen( cmds, stdout=stdout, stderr=stderr, cwd=working_folder, env=environ_vars ) if not synchronous: return None, None, None out, err = p.communicate() ret_code = p.returncode logger.info("output: %s", out) if ret_code == 0: self.read_state_file() else: logger.warning("error: %s", err) self.temp_var_files.clean_up() if capture_output is True: out = out.decode() err = err.decode() else: out = None err = None if ret_code and raise_on_error: raise TerraformCommandError(ret_code, " ".join(cmds), out=out, err=err) return ret_code, out, err def output( self, *args, capture_output: bool = True, **kwargs ) -> Union[None, str, Dict[str, str], Dict[str, Dict[str, str]]]: """Refer https://www.terraform.io/docs/commands/output.html Note that this method does not conform to the (ret_code, out, err) return convention. To use the "output" command with the standard convention, call "output_cmd" instead of "output". :param args: Positional arguments. There is one optional positional argument NAME; if supplied, the returned output text will be the json for a single named output value. :param kwargs: Named options, passed to the command. In addition, 'full_value': If True, and NAME is provided, then the return value will be a dict with "value', 'type', and 'sensitive' properties. :return: None, if an error occured Output value as a string, if NAME is provided and full_value is False or not provided Output value as a dict with 'value', 'sensitive', and 'type' if NAME is provided and full_value is True. dict of named dicts each with 'value', 'sensitive', and 'type', if NAME is not provided """ kwargs["json"] = IsFlagged if capture_output is False: raise ValueError("capture_output is required for this method") global_opts = self._generate_default_general_options(False) ret, out, _ = self.output_cmd(global_opts, *args, **kwargs) if ret: return None return json.loads(out.lstrip()) def read_state_file(self, file_path=None) -> None: """Read .tfstate file :param file_path: relative path to working dir :return: states file in dict type """ working_dir = self.working_dir or "" file_path = file_path or self.state or "" if not file_path: backend_path = os.path.join(file_path, ".terraform", "terraform.tfstate") if os.path.exists(os.path.join(working_dir, backend_path)): file_path = backend_path else: file_path = os.path.join(file_path, "terraform.tfstate") file_path = os.path.join(working_dir, file_path) self.tfstate = Tfstate.load_file(file_path) def set_workspace(self, workspace, *args, **kwargs) -> CommandOutput: """Set workspace :param workspace: the desired workspace. :return: status """ global_opts = self._generate_default_general_options(False) return self.cmd(global_opts, "workspace", "select", workspace, *args, **kwargs) def create_workspace(self, workspace, *args, **kwargs) -> CommandOutput: """Create workspace :param workspace: the desired workspace. :return: status """ global_opts = self._generate_default_general_options(False) return self.cmd(global_opts, "workspace", "new", workspace, *args, **kwargs) def delete_workspace(self, workspace, *args, **kwargs) -> CommandOutput: """Delete workspace :param workspace: the desired workspace. :return: status """ global_opts = self._generate_default_general_options(False) return self.cmd(global_opts, "workspace", "delete", workspace, *args, **kwargs) def show_workspace(self, **kwargs) -> CommandOutput: """Show workspace, this command does not need the [DIR] part :return: workspace """ global_opts = self._generate_default_general_options(False) return self.cmd(global_opts, "workspace", "show", **kwargs) def _generate_default_args(self, dir_or_plan: Optional[str]) -> Sequence[str]: if (self.terraform_version < 1.0 and dir_or_plan): return [dir_or_plan] else: return [] def _generate_default_general_options(self, dir_or_plan: Optional[str]) -> Dict[str, Any]: if (self.terraform_version >= 1.0 and dir_or_plan): return {"chdir": dir_or_plan} else: return {} def _generate_default_options( self, input_options: Dict[str, Any] ) -> Dict[str, Any]: return { "state": self.state, "target": self.targets, "var": self.variables, "var_file": self.var_file, "parallelism": self.parallelism, "no_color": IsFlagged, "input": False, **input_options, } def _generate_cmd_options(self, **kwargs) -> List[str]: """ """ result = [] for option, value in kwargs.items(): if "_" in option: option = option.replace("_", "-") if isinstance(value, list): for sub_v in value: result += [f"-{option}={sub_v}"] continue if isinstance(value, dict): if "backend-config" in option: for bk, bv in value.items(): result += [f"-backend-config={bk}={bv}"] continue # since map type sent in string won't work, create temp var file for # variables, and clean it up later elif option == "var": # We do not create empty var-files if there is no var passed. # An empty var-file would result in an error: An argument or block definition is required here if value: filename = self.temp_var_files.create(value) result += [f"-var-file={filename}"] continue # simple flag, if value is IsFlagged: result += [f"-{option}"] continue if value is None or value is IsNotFlagged: continue if isinstance(value, bool): value = "true" if value else "false" result += [f"-{option}={value}"] return result def __exit__(self, exc_type, exc_value, traceback) -> None: self.temp_var_files.clean_up() def __getattr__(self, item: str) -> Callable: def wrapper(*args, **kwargs): cmd_name = str(item) if cmd_name.endswith("_cmd"): cmd_name = cmd_name[:-4] logger.debug("called with %r and %r", args, kwargs) global_opts = self._generate_default_general_options(False) return self.cmd(global_opts, cmd_name, *args, **kwargs) return wrapper class VariableFiles: def __init__(self): self.files = [] def create(self, variables: Dict[str, str]) -> str: with tempfile.NamedTemporaryFile( "w+t", suffix=".tfvars.json", delete=False ) as temp: logger.debug("%s is created", temp.name) self.files.append(temp) logger.debug("variables wrote to tempfile: %s", variables) temp.write(json.dumps(variables)) file_name = temp.name return file_name def clean_up(self): for f in self.files: os.unlink(f.name) self.files = []