store and retrieve JSON DAG node

This is silly, converting to JSON and then parsing it.
So far IPFS HTTP API can't give us CBOR directly:
ipfs/kubo#4313

Cargo.toml

@@ -9,3 +9,6 @@ edition = "2018"
 [dependencies]
 ipfs-api = "0.9.0"
 tokio = { version = "0.2", features = ["full"] }
+futures = "0.3"
+serde = "1.0"
+serde_json = "1.0"

rustfmt.toml

@@ -0,0 +1,67 @@
+max_width = 100
+chain_width = 100
+hard_tabs = true
+tab_spaces = 4
+newline_style = "Auto"
+use_small_heuristics = "Default"
+indent_style = "Block"
+wrap_comments = false
+format_code_in_doc_comments = false
+comment_width = 80
+normalize_comments = false
+normalize_doc_attributes = false
+license_template_path = ""
+format_strings = false
+format_macro_matchers = false
+format_macro_bodies = true
+empty_item_single_line = true
+struct_lit_single_line = true
+fn_single_line = false
+where_single_line = false
+imports_indent = "Block"
+imports_layout = "Mixed"
+merge_imports = false
+reorder_imports = true
+reorder_modules = true
+reorder_impl_items = false
+type_punctuation_density = "Wide"
+space_before_colon = false
+space_after_colon = true
+spaces_around_ranges = false
+binop_separator = "Front"
+remove_nested_parens = true
+combine_control_expr = true
+overflow_delimited_expr = false
+struct_field_align_threshold = 0
+enum_discrim_align_threshold = 0
+match_arm_blocks = true
+match_arm_leading_pipes = "Never"
+force_multiline_blocks = false
+fn_args_layout = "Tall"
+brace_style = "SameLineWhere"
+control_brace_style = "AlwaysSameLine"
+trailing_semicolon = true
+trailing_comma = "Vertical"
+match_block_trailing_comma = false
+blank_lines_upper_bound = 1
+blank_lines_lower_bound = 0
+edition = "2018"
+version = "One"
+inline_attribute_width = 0
+merge_derives = true
+use_try_shorthand = false
+use_field_init_shorthand = false
+force_explicit_abi = true
+condense_wildcard_suffixes = false
+color = "Auto"
+unstable_features = true
+disable_all_formatting = false
+skip_children = false
+hide_parse_errors = false
+error_on_line_overflow = false
+error_on_unformatted = false
+report_todo = "Never"
+report_fixme = "Never"
+ignore = []
+emit_mode = "Files"
+make_backup = false

src/main.rs

@@ -1,14 +1,59 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 Shawn Rutledge
+**
+** This file is free software; you can redistribute it and/or
+** modify it under the terms of the GNU General Public License
+** version 3 as published by the Free Software Foundation
+** and appearing in the file LICENSE included in the packaging
+** of this file.
+**
+** This code is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+** GNU General Public License for more details.
+**
+****************************************************************************/
+
+use futures::TryStreamExt;
 use ipfs_api::IpfsClient;
+use serde_json::Value;
+use std::any::type_name;
 use std::io::Cursor;
 use tokio;
 
+fn type_of<T>(_: T) -> &'static str {
+    type_name::<T>()
+}
+
 #[tokio::main]
 async fn main() {
     let client = IpfsClient::default();
-    let data = Cursor::new("Hello World!");
+    let data = r#"{"hello":423453343}"#;
+    let dag_node = Cursor::new(data);
+    println!("{}", type_of(data));
+
+    let response = client
+        .dag_put(dag_node)
+        .await
+        .expect("error adding dag node");
+
+    let cid = response.cid.cid_string;
+    eprintln!("added: {:?}", cid);
 
-    match client.add(data).await {
-        Ok(res) => println!("{}", res.hash),
-        Err(e) => eprintln!("error adding file: {}", e)
+    match client
+        .dag_get(&cid)
+        .map_ok(|chunk| chunk.to_vec())
+        .try_concat()
+        .await
+    {
+        Ok(bytes) => {
+            println!("{}", String::from_utf8_lossy(&bytes[..]));
+            let deserialized: Value = serde_json::from_slice(&bytes).unwrap();
+            println!("deserialized = {:?}", deserialized);
+        }
+        Err(e) => {
+            eprintln!("error reading dag node: {}", e);
+        }
     }
 }