- Remove Mstch engine

- Add varToBool function

CMakeLists.txt

@@ -2,39 +2,13 @@ cmake_minimum_required(VERSION 3.5)
 
 set(TARGET muenvsubst)
 
-project(${TAGRET} LANGUAGES CXX)
+project(${TARGET} LANGUAGES CXX)
 
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
-find_package(args-parser REQUIRED)
-find_package(mbits-mstch REQUIRED)
-find_package(inja REQUIRED)
-
 if(CMAKE_BUILD_TYPE STREQUAL "Release")
   add_link_options(-static -static-libgcc -static-libstdc++ -s)
 endif()
 
-set(SOURCES
-  src/inja_renderer.cpp
-  src/inja_renderer.h
-  src/main.cpp
-  src/mstch_renderer.cpp
-  src/mstch_renderer.h
-  src/tools.cpp
-  src/tools.h
-)
-
-add_executable(${TARGET} ${SOURCES})
-
-target_link_libraries(${TARGET}
-  args-parser::args-parser
-  mbits::mstch
-  pantor::inja
-)
-
-include(GNUInstallDirs)
-install(TARGETS ${TARGET}
-  LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
-  RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
-)
+add_subdirectory(cli)

Dockerfile.uclibc

@@ -27,4 +27,4 @@ RUN set -x && \
     cd /build && \
     cmake /sources -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=Release && \
     cmake --build . && \
-    upx -9 --brute muenvsubst
+    upx -9 --brute cli/muenvsubst

README.md

@@ -5,7 +5,6 @@ Substitutes environment variables using one of the templating engines, as
 
 This is a list of supported template engines:
 
-- `mstch` - [Mustache templates](https://github.com/no1msd/mstch)
 - `inja` - [Inja templates](https://pantor.github.io/inja/)
 
 One of the advantages of this utility is that it is built in a small static binary without any dependencies.
@@ -27,23 +26,14 @@ sudo chmod +x /usr/local/bin/muenvsubst
 Substitutes environment variables using one of the templating engines, as 
 envsubst does. 
 
-USAGE: ./muenvsubst [ -e, --engine <arg> ] [ -h, --help <arg> ] [ -V, 
-       --version ] 
+USAGE: ./muenvsubst [ -h, --help <arg> ] [ -V, --version ] 
 
 OPTIONAL:
- -e, --engine <arg> Use template engine. Supported engines: mstch, inja. 
-                    Default is: inja 
+ -h, --help <arg> Print this help. 
 
- -h, --help <arg>   Print this help. 
-
- -V, --version      Output version information and exit
+ -V, --version    Output version information and exit
 ```
 
-## Mustache syntax
-
-[Mstch](https://github.com/no1msd/mstch) library fully supports original [{{ Mustache }}](https://mustache.github.io/) 
-syntax described [here](https://mustache.github.io/mustache.5.html).
-
 ## Inja syntax
 
 [Inja](https://pantor.github.io/inja/) inspired by Python's Jinja and supports subset of original Jinja syntax. It 
@@ -60,6 +50,16 @@ Additional functions:
   split(text: string, delimiter: string): string
   ```
 
+- Convenient convert boolean variable to boolean type:
+
+  ```
+  varToBool(varName: string): boolean
+  ```
+
+  This function supports strings "true", "yes", "on", "1" for `true` value, other values supposed to be a `false` value. 
+
+  Example: `set DO_SMTH = varToBool("DO_SMTH")`
+
 - Throw error:
 
   ```
@@ -84,7 +84,7 @@ Hello, John!
 
 - Simple variable substitution:
   ```sh
-  echo "Hello, {{ USER }}!" | muenvsubst -e inja
+  echo "Hello, {{ USER }}!" | muenvsubst
   ```
 
   then output will be: 
@@ -96,7 +96,7 @@ Hello, John!
 - Using variable and function:
 
   ```sh
-  muenvsubst -e inja <<EOF
+  muenvsubst <<EOF
   {%- set username = upper(USER) -%}
   Hello, {{ username }}!
   EOF
@@ -111,7 +111,7 @@ Hello, John!
 - Render conditional block:
 
   ```sh
-  USE_GREETER=no USE_GOODBYER=yes muenvsubst -e inja << EOF
+  USE_GREETER=no USE_GOODBYER=yes muenvsubst << EOF
   {%- if USE_GREETER=="yes" -%}
   Hello, {{ USER }}!
   {%- endif -%}
@@ -130,7 +130,7 @@ Hello, John!
 - Using split and loop:
   
   ```sh
-  USERS="John,Mark,Peter" muenvsubst -e inja << EOF
+  USERS="John,Mark,Peter" muenvsubst << EOF
   {%- for user in split(USERS,",") -%}
   Hello, {{ user }}!
   {%- endfor -%}

build-musl.sh

@@ -6,5 +6,5 @@ docker build --progress plain --tag ${IMAGE_NAME} -f Dockerfile.musl .
 
 id=$(docker create ${IMAGE_NAME})
 mkdir -p dist
-docker cp $id:/build/muenvsubst ./dist/
+docker cp $id:/build/cli/muenvsubst ./dist/
 docker rm -v $id

build-uclibc.sh

@@ -6,5 +6,5 @@ docker build --progress=plain --tag ${IMAGE_NAME} -f Dockerfile.uclibc .
 
 id=$(docker create ${IMAGE_NAME})
 mkdir -p dist
-docker cp $id:/build/muenvsubst ./dist/
+docker cp $id:/build/cli/muenvsubst ./dist/
 docker rm -v $id

cli/CMakeLists.txt

@@ -0,0 +1,25 @@
+set(TARGET muenvsubst)
+
+find_package(args-parser REQUIRED)
+find_package(inja REQUIRED)
+
+set(SOURCES
+  inja_renderer.cpp
+  inja_renderer.h
+  main.cpp
+  tools.cpp
+  tools.h
+)
+
+add_executable(${TARGET} ${SOURCES})
+
+target_link_libraries(${TARGET}
+  args-parser::args-parser
+  pantor::inja
+)
+
+include(GNUInstallDirs)
+install(TARGETS ${TARGET}
+  LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+  RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
+)

cli/inja_renderer.cpp

@@ -0,0 +1,72 @@
+#include "inja_renderer.h"
+
+#include <inja/inja.hpp>
+#include <sstream>
+#include <stdexcept>
+
+#include "tools.h"
+
+using namespace std;
+using namespace std::placeholders;
+
+inline void toLower(string& res)
+{
+    transform(res.begin(), res.end(), res.begin(), [](unsigned char c) { return std::tolower(c); });
+}
+
+inline void ltrim(std::string& s)
+{
+    s.erase(s.begin(), std::find_if(s.begin(), s.end(), [](unsigned char ch) { return !std::isspace(ch); }));
+}
+
+inline void rtrim(std::string& s)
+{
+    s.erase(std::find_if(s.rbegin(), s.rend(), [](unsigned char ch) { return !std::isspace(ch); }).base(), s.end());
+}
+
+inja::json split(const inja::Arguments& args)
+{
+    if (args.size() != 2)
+        throw runtime_error("Expected 2 parameters: split(s: string, delimiter: string): string[]");
+    auto s = args[0]->get<string>();
+    auto delimiter = args[1]->get<string>();
+    return stringSplit(s, delimiter);
+}
+
+inja::json varToBool(const inja::Arguments& args, inja::json envs)
+{
+    if (args.size() != 1)
+        throw runtime_error("Expected 1 parameters: toBool(varName: string): bool");
+    auto name = args[0]->get<string>();
+    auto val = envs[name];
+    if (val.is_null())
+        return false;
+    if (val.is_boolean())
+        return val.get<bool>();
+    if (val.is_string()) {
+        auto s = val.get<string>();
+        toLower(s);
+        ltrim(s);
+        rtrim(s);
+        return s == "true" || s == "yes" || s == "on" || s == "1";
+    }
+    throw runtime_error((stringstream() << "Unsupported env value type for name " << name).str());
+}
+
+inja::json error(const inja::Arguments& args)
+{
+    if (args.size() != 1)
+        throw runtime_error("Expected 1 parameters: error(message: string)");
+    auto message = args[0]->get<string>();
+    throw runtime_error(message);
+}
+
+string renderWithInja(const string& tmpl, char** envp)
+{
+    auto envs = getAllEnvs<inja::json>(envp);
+    inja::Environment env;
+    env.add_callback("split", bind(split, _1));
+    env.add_callback("error", bind(error, _1));
+    env.add_callback("varToBool", [&](const inja::Arguments& args) { return varToBool(args, envs); });
+    return env.render(tmpl, envs);
+}

cli/main.cpp

@@ -0,0 +1,40 @@
+#include <args-parser/all.hpp>
+
+#include "inja_renderer.h"
+#include "tools.h"
+
+using namespace std;
+using namespace std::placeholders;
+using namespace Args;
+
+const char* APP_VERSION = "1.2.0";
+
+int main(int argc, char** argv, char** envp)
+{
+    bool showVersion = false;
+    CmdLine cmd(argc, argv);
+    cmd.addHelp(
+        true, argv[0], "Substitutes environment variables using one of the templating engines, as envsubst does.");
+    cmd.addArgWithFlagAndName('V', "version", false, false, "Output version information and exit");
+    try {
+        cmd.parse();
+
+        if (cmd.isDefined("-V")) {
+            cout << "1.2.0" << endl;
+            return 0;
+        }
+
+        auto tmpl = readAllInput();
+        cout << renderWithInja(tmpl, envp);
+
+    } catch (const HelpHasBeenPrintedException&) {
+        return 0;
+    } catch (const BaseException& x) {
+        cerr << x.desc() << "\n";
+        return 1;
+    } catch (const exception& x) {
+        cerr << x.what() << "\n";
+        return 1;
+    }
+    return 0;
+}

conanfile.txt

@@ -1,6 +1,5 @@
 [requires]
 args-parser/6.3.3
-mbits-mstch/1.0.4
 inja/3.4.0
 
 [generators]