implement format json

Cargo.lock

@@ -90,6 +90,7 @@ dependencies = [
  "libc",
  "num-integer",
  "num-traits",
+ "serde",
  "time",
  "winapi",
 ]
@@ -487,6 +488,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "serde_json"
+version = "1.0.64"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "799e97dc9fdae36a5c8b8f2cae9ce2ee9fdce2058c57a93e6099d919fd982f79"
+dependencies = [
+ "itoa",
+ "ryu",
+ "serde",
+]
+
 [[package]]
 name = "serde_yaml"
 version = "0.8.17"
@@ -597,6 +609,7 @@ dependencies = [
  "regex",
  "rusqlite",
  "serde",
+ "serde_json",
  "serde_yaml",
  "tempfile",
  "textwrap 0.14.2",

Cargo.toml

@@ -12,7 +12,7 @@ path = "src/main.rs"
 
 [dependencies]
 clap = "2"
-chrono = "0.4"
+chrono = { version = "0.4", features = ["serde"] }
 rusqlite = { version = "0.25.3", features = ["chrono"] }
 thiserror = "*"
 directories = "*"
@@ -26,6 +26,7 @@ csv = "1.1"
 regex = "1.5"
 lazy_static = "1.4"
 tempfile = "3"
+serde_json = "1.0"
 
 [dev-dependencies]
 pretty_assertions = "0.7.2"

src/error.rs

@@ -69,6 +69,11 @@ some human times, for now restricted to time ago:
     #[error("CSV Error: {0}")]
     CSVError(#[from] csv::Error),
 
+    #[error("Could not serialize to json.
+
+{0}")]
+    SerdeJsonError(#[from] serde_json::Error),
+
     #[error("Corrupted data found in the database:
 {0}
 

src/formatters.rs

@@ -9,12 +9,14 @@ use crate::models::Entry;
 
 pub mod text;
 pub mod csv;
+pub mod json;
 
 #[derive(Debug, Serialize, Deserialize)]
 #[serde(rename_all = "lowercase")]
 pub enum Formatter {
     Text,
     Csv,
+    Json,
     Custom(String),
 }
 
@@ -35,6 +37,7 @@ impl Formatter {
         match &self {
             Formatter::Text => text::print_formatted(entries, out, now, ids)?,
             Formatter::Csv => csv::print_formatted(entries, out, ids)?,
+            Formatter::Json => json::print_formatted(entries, out)?,
             Formatter::Custom(name) => {
                 panic!("attempted custom formatter with name {} which is not implemented", name);
             }
@@ -53,6 +56,7 @@ impl FromStr for Formatter {
         Ok(match &*lower {
             "text" => Formatter::Text,
             "csv" => Formatter::Csv,
+            "json" => Formatter::Json,
             custom_format => Formatter::Custom(custom_format.into()),
         })
     }

src/formatters/json.rs

@@ -0,0 +1,8 @@
+use std::io::Write;
+
+use crate::models::Entry;
+use crate::error::Result;
+
+pub fn print_formatted<W: Write>(entries: Vec<Entry>, out: &mut W) -> Result<()> {
+    Ok(serde_json::to_writer(out, &entries)?)
+}

src/models.rs

@@ -1,6 +1,7 @@
 use chrono::{DateTime, Utc};
+use serde::Serialize;
 
-#[derive(Debug)]
+#[derive(Debug, Serialize)]
 pub struct Entry {
     pub id: u64,
     pub note: Option<String>,