Add option to print output as JSON (#9)

Make StatusContext struct serializable using serde so that it can be serialized to JSON. 
Added command line option that lets users print output as JSON. 
The new command line option must be set along with the verbose flag.

cfn-guard/Cargo.toml

@@ -9,7 +9,7 @@ edition = "2018"
 [dependencies]
 nom = "5.1.2"
 nom_locate = "2.0.0"
-indexmap = "1.6.0"
+indexmap = { version = "1.6.0", features = ["serde-1"] }
 regex = "1.3.9"
 simple_logger = "1.3.0"
 clap = "2.29.0"

cfn-guard/src/commands/tracker.rs

@@ -1,10 +1,12 @@
 use crate::rules::{Evaluate, EvaluationContext, Result, Status, EvaluationType, path_value::PathAwareValue};
 use nom::lib::std::fmt::Formatter;
+use serde::{Serialize};
 
-#[derive(Debug)]
+#[derive(Serialize, Debug)]
 pub(super) struct StatusContext {
     pub(super) eval_type: EvaluationType,
     pub(super) context: String,
+    #[serde(skip_serializing)]
     pub(super) msg: Option<String>,
     pub(super) from: Option<PathAwareValue>,
     pub(super) to: Option<PathAwareValue>,

cfn-guard/src/commands/validate.rs

@@ -48,6 +48,8 @@ impl Command for Validate {
                 .help("sort by last modified times within a directory"))
             .arg(Arg::with_name("verbose").long("verbose").short("v").required(false)
                 .help("verbose logging"))
+            .arg(Arg::with_name("print-json").long("print-json").short("p").required(false)
+                .help("Print output in json format"))
     }
 
     fn execute(&self, app: &ArgMatches<'_>) -> Result<()> {
@@ -67,6 +69,7 @@ impl Command for Validate {
             false
         };
 
+        let print_json = app.is_present("print-json");
 
         let files = get_files(file, cmp)?;
         let data_files = get_files(data, cmp)?;
@@ -83,7 +86,7 @@ impl Command for Validate {
                         },
 
                         Ok(rules) => {
-                            evaluate_against_data_files(&data_files, &rules, verbose)?
+                            evaluate_against_data_files(&data_files, &rules, verbose, print_json)?
                         }
                     }
                 }
@@ -96,7 +99,8 @@ impl Command for Validate {
 #[derive(Debug)]
 struct ConsoleReporter<'r> {
     root_context: StackTracker<'r>,
-    verbose: bool
+    verbose: bool,
+    print_json: bool
 }
 
 fn colored_string(status: Option<Status>) -> ColoredString {
@@ -155,42 +159,50 @@ pub(super) fn print_context(cxt: &StatusContext, depth: usize) {
 }
 
 impl<'r, 'loc> ConsoleReporter<'r> {
-    fn new(root: StackTracker<'r>, verbose: bool) -> Self {
+    fn new(root: StackTracker<'r>, verbose: bool, print_json: bool) -> Self {
         ConsoleReporter {
             root_context: root,
             verbose,
+            print_json,
         }
     }
 
     fn report(self) {
-        print!("{}", "Summary Report".underline());
         let stack = self.root_context.stack();
         let top = stack.first().unwrap();
-        println!(" Overall File Status = {}", colored_string(top.status));
-
-        let longest = top.children.iter()
-            .max_by(|f, s| {
-                (*f).context.len().cmp(&(*s).context.len())
-            })
-            .map(|elem| elem.context.len())
-            .unwrap_or(20);
-
-       for container in &top.children {
-           print!("{}", container.context);
-           let container_level = container.context.len();
-           let spaces = longest - container_level + 4;
-           for _idx in 0..spaces {
-               print!(" ");
-           }
-           println!("{}", colored_string(container.status));
-        }
 
-        if self.verbose {
-            println!("Evaluation Tree");
-            for each in &top.children {
-                print_context(each, 1);
-            }
+        if self.verbose && self.print_json {
+            let serialized_user = serde_json::to_string_pretty(&top.children).unwrap();
+            println!("{}", serialized_user);
         }
+        else {
+            print!("{}", "Summary Report".underline());
+            println!(" Overall File Status = {}", colored_string(top.status));
+
+            let longest = top.children.iter()
+                .max_by(|f, s| {
+                    (*f).context.len().cmp(&(*s).context.len())
+                })
+                .map(|elem| elem.context.len())
+                .unwrap_or(20);
+
+           for container in &top.children {
+               print!("{}", container.context);
+               let container_level = container.context.len();
+               let spaces = longest - container_level + 4;
+               for _idx in 0..spaces {
+                   print!(" ");
+               }
+               println!("{}", colored_string(container.status));
+            }
+
+           if self.verbose {
+               println!("Evaluation Tree");
+               for each in &top.children {
+                   print_context(each, 1);
+               }
+           }
+       }
     }
 }
 
@@ -237,7 +249,7 @@ impl<'r> ConsoleReporter<'r> {
 
 }
 
-fn evaluate_against_data_files(data_files: &[PathBuf], rules: &RulesFile<'_>, verbose: bool) -> Result<()> {
+fn evaluate_against_data_files(data_files: &[PathBuf], rules: &RulesFile<'_>, verbose: bool, print_json: bool) -> Result<()> {
     let mut iterator = iterate_over(data_files, |content, _| {
         match serde_json::from_str::<serde_json::Value>(&content) {
             Ok(value) => PathAwareValue::try_from(value),
@@ -254,7 +266,7 @@ fn evaluate_against_data_files(data_files: &[PathBuf], rules: &RulesFile<'_>, ve
             Ok(root) => {
                 let root_context = RootScope::new(rules, &root);
                 let stacker = StackTracker::new(&root_context);
-                let reporter = ConsoleReporter::new(stacker, verbose);
+                let reporter = ConsoleReporter::new(stacker, verbose, print_json);
                 rules.evaluate(&root, &reporter)?;
                 reporter.report();
             }

cfn-guard/src/rules/mod.rs

@@ -13,10 +13,11 @@ use colored::*;
 use crate::rules::path_value::PathAwareValue;
 use nom::lib::std::convert::TryFrom;
 use crate::rules::errors::ErrorKind;
+use serde::{Serialize};
 
 pub(crate) type Result<R> = std::result::Result<R, Error>;
 
-#[derive(Debug, Clone, PartialEq, Copy)]
+#[derive(Debug, Clone, PartialEq, Copy, Serialize)]
 pub(crate) enum Status {
     PASS,
     FAIL,
@@ -49,7 +50,7 @@ impl TryFrom<&str> for Status {
     }
 }
 
-#[derive(Debug, Clone, PartialEq, Copy)]
+#[derive(Debug, Clone, PartialEq, Copy, Serialize)]
 pub(crate) enum EvaluationType {
     File,
     Rule,

cfn-guard/src/rules/path_value.rs

@@ -18,8 +18,9 @@ use super::{EvaluationContext, Evaluate, Status};
 use std::cmp::Ordering;
 use crate::rules::evaluate::AutoReport;
 use crate::rules::EvaluationType;
+use serde::{Serialize};
 
-#[derive(Clone, Debug, PartialEq, Eq, Hash)]
+#[derive(Clone, Debug, PartialEq, Eq, Hash, Serialize)]
 pub(crate) struct Path(pub(crate) String);
 
 impl std::fmt::Display for Path {
@@ -103,14 +104,14 @@ impl Path {
     }
 }
 
-#[derive(PartialEq, Debug, Clone)]
+#[derive(PartialEq, Debug, Clone, Serialize)]
 pub(crate) struct MapValue {
     keys: Vec<PathAwareValue>,
     values: indexmap::IndexMap<String, PathAwareValue>,
 }
 
 
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Serialize)]
 pub(crate) enum PathAwareValue {
     Null(Path),
     String((Path, String)),

cfn-guard/src/rules/values.rs

@@ -7,6 +7,8 @@ use nom::lib::std::fmt::Formatter;
 use crate::rules::errors::{Error};
 use crate::rules::parser::Span;
 
+use serde::{Serialize};
+
 #[derive(PartialEq, Debug, Clone, Hash, Copy)]
 pub enum CmpOperator {
     Eq,
@@ -112,7 +114,7 @@ impl Hash for Value {
 //
 //    .X in r(10, 20]
 //    .X in r(10, 20)
-#[derive(PartialEq, Debug, Clone)]
+#[derive(PartialEq, Debug, Clone, Serialize)]
 pub struct RangeType<T: PartialOrd> {
     pub upper: T,
     pub lower: T,