Re: [Tarantool-patches] [PATCHv2 1/2] core: add setting error injections via env

[Sergey Bronnikov via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

Hello,

thanks for the patch!

see my comments below

On 18.02.2021 22:30, Artem Starshov wrote:
> Sometimes, it's useful to set error injections via environment
> variables and this commit adds this opportunity.
>
> e.g: `ERRINJ_WAL_WRITE=true tarantool` will be launched with
> ERRINJ_WAL_WRITE setted to true.
>
> Errinjs with bool parameters can should be set as "true", "TRUE",
> "false" or "FALSE".
>
> Errinjs with int or double parameters should be whole valid ("123s" is invalid).
> e.g. for int or double: "123", "-1", "2.34", "+2.34".
>
> Part of #5040
> ---
>   src/lib/core/errinj.c                         | 26 +++++++++++++++++++
>   src/lib/core/errinj.h                         |  5 ++++
>   src/main.cc                                   |  1 +
>   .../errinj_set_with_enviroment_vars.test.lua  | 14 ++++++++++
>   ...errinj_set_with_enviroment_vars_script.lua | 13 ++++++++++
>   5 files changed, 59 insertions(+)
>   create mode 100755 test/box-tap/errinj_set_with_enviroment_vars.test.lua
>   create mode 100644 test/box-tap/errinj_set_with_enviroment_vars_script.lua
>
> diff --git a/src/lib/core/errinj.c b/src/lib/core/errinj.c
> index d3aa0ca4f..3c1194f20 100644
> --- a/src/lib/core/errinj.c
> +++ b/src/lib/core/errinj.c
> @@ -66,3 +66,29 @@ int errinj_foreach(errinj_cb cb, void *cb_ctx) {
>   	}
>   	return 0;
>   }
> +
> +void errinj_set_with_environment_vars() {
> +    for (enum errinj_id i = 0; i < errinj_id_MAX; i++) {
> +        struct errinj *inj = &errinjs[i];
> +        const char *env_value = getenv(inj->name);
> +        if (!env_value || *env_value == '\0')
> +            continue;
> +
> +        if (inj->type == ERRINJ_INT) {
> +            char *end;
> +            int64_t int_value = strtoll(env_value, &end, 10);
> +            if (*end == '\0')
> +                inj->iparam = int_value;
> +        } else if (inj->type == ERRINJ_BOOL) {
> +            if (strcmp(env_value, "false") == 0 || strcmp(env_value, "FALSE") == 0)

1. What happen if someone set boolean value to "False"?

May be it's worth to convert env_value to lowercase and then compare? 
The same question for "true".


> +                inj->bparam = false;
> +            else if (strcmp(env_value, "true") == 0 || strcmp(env_value, "TRUE") == 0)
> +                inj->bparam = true;
> +        } else if (inj->type == ERRINJ_DOUBLE) {
> +            char *end;
> +            double double_value = strtod(env_value, &end);
> +            if (*end == '\0')
> +                inj->dparam = double_value;
> +        }
> +    }
> +}
> diff --git a/src/lib/core/errinj.h b/src/lib/core/errinj.h
> index 814c57c2e..d76aedf7a 100644
> --- a/src/lib/core/errinj.h
> +++ b/src/lib/core/errinj.h
> @@ -168,6 +168,11 @@ typedef int (*errinj_cb)(struct errinj *e, void *cb_ctx);
>   int
>   errinj_foreach(errinj_cb cb, void *cb_ctx);
>   
> +/**
> + * Set injections by scanning ERRINJ_$(NAME) in environment variables
> + */
> +void errinj_set_with_environment_vars();
> +
>   #ifdef NDEBUG
>   #  define ERROR_INJECT(ID, CODE)
>   #  define ERROR_INJECT_WHILE(ID, CODE)
> diff --git a/src/main.cc b/src/main.cc
> index 2fce81bb3..58a660689 100644
> --- a/src/main.cc
> +++ b/src/main.cc
> @@ -710,6 +710,7 @@ main(int argc, char **argv)
>   	memtx_tx_manager_init();
>   	crypto_init();
>   	systemd_init();
> +	errinj_set_with_environment_vars();
>   	tarantool_lua_init(tarantool_bin, main_argc, main_argv);
>   
>   	start_time = ev_monotonic_time();
> diff --git a/test/box-tap/errinj_set_with_enviroment_vars.test.lua b/test/box-tap/errinj_set_with_enviroment_vars.test.lua
> new file mode 100755
> index 000000000..f52ebcc11
> --- /dev/null
> +++ b/test/box-tap/errinj_set_with_enviroment_vars.test.lua
> @@ -0,0 +1,14 @@
> +#!/usr/bin/env tarantool
> +local fio = require('fio')
> +
> +-- Execute errinj_set_with_enviroment_vars_script.lua
> +-- via tarantool with presetted environment variables.
> +local TARANTOOL_PATH = arg[-1]
> +local set_env_str = 'ERRINJ_TESTING=true ERRINJ_WAL_WRITE_PARTIAL=1 ERRINJ_VY_READ_PAGE_TIMEOUT=2.5'
> +local script_file = fio.pathjoin(

2. variable name should reflect a purpose of variable.

name is about script file, when variable contains a path to a file.

> +        os.getenv('PWD'),
> +        'box-tap',
> +        'errinj_set_with_enviroment_vars_script.lua')
> +local shell_command = ('%s %s %s'):format(set_env_str, TARANTOOL_PATH, script_file)
> +
> +os.exit(os.execute(shell_command))
> diff --git a/test/box-tap/errinj_set_with_enviroment_vars_script.lua b/test/box-tap/errinj_set_with_enviroment_vars_script.lua
> new file mode 100644
> index 000000000..b8903b907
> --- /dev/null
> +++ b/test/box-tap/errinj_set_with_enviroment_vars_script.lua
> @@ -0,0 +1,13 @@
> +-- Script for box-tap/errinj_set_with_enviroment_vars.test.lua test.
> +
> +local tap = require('tap')
> +local errinj = box.error.injection
> +
> +local res = tap.test('set errinjs via environment variables', function(test)
> +    test:plan(3)
> +    test:is(errinj.get('ERRINJ_TESTING'), true, "set bool error injection")
> +    test:is(errinj.get('ERRINJ_WAL_WRITE_PARTIAL'), 1, "set int error injection")
> +    test:is(errinj.get('ERRINJ_VY_READ_PAGE_TIMEOUT'), 2.5, "set double error injection")
> +end)
> +
> +os.exit(res and 0 or 1)