Create Cassandra Migrations from Rust Structs

Custom derive to simplify cassandra table creation from rust structs

Installation

cassandra_macro = "0.1.0" cassandra_macro_derive = "0.1.0"

Example with primary key

```rust use cassandramacro::Cassandra; use cassandramacro_derive::Cassandra;

[table(keyspace = "fog")]

[derive(Debug, Cassandra)]

pub struct TestRust { #[column(type = "TEXT", primarykey)] keyone: String, }

fn main() { let f = TestRust { key_one: String::from("one") };

println!("{}", f.create_table_cql()); /// CREATE TABLE IF NOT EXISTS fog.test_rust (key_one TEXT, PRIMARY KEY (key_one));
println!("{}", f.drop_table_cql());   /// DROP TABLE IF EXISTS fog.test_rust
println!("{}", f.key_space());        /// fog
println!("{}", f.table_name());       /// test_rust

}

```

Example with compound key

```rust use cassandramacro::Cassandra; use cassandramacro_derive::Cassandra;

[table(keyspace = "fog")]

[derive(Debug, Cassandra)]

pub struct TestRust { #[column(type = "UUID", compoundkey(position = 2))] keyone: String,

#[column(type = "TEXT", compound_key(position = 1))]
key_two: String,

}

fn main() { let f = TestRust { keyone: String::from("one"), keytwo: String::from("two") };

println!("{}", f.create_table_cql()); ///CREATE TABLE IF NOT EXISTS fog.test_rust (key_one UUID,key_two TEXT, PRIMARY KEY (key_two,key_one) ) ; 
println!("{}", f.drop_table_cql());
println!("{}", f.key_space());
println!("{}", f.table_name());

} ```

Example with compound key & cluster key & options

```rust use cassandramacro::Cassandra; use cassandramacro_derive::Cassandra;

/// Options are separated with '|' char

[table(keyspace = "fog", options = "comment='From RUST' | COMPACTION = { 'class' : 'SizeTieredCompactionStrategy' }")]

[derive(Debug, Cassandra)]

pub struct TestRust { #[column(type = "UUID", compoundkey(position = 2))] keyone: String,

#[column(type = "TEXT", compound_key(position = 1))]
key_two: String,

#[column(type = "TIMESTAMP", cluster_key(order = "DESC", position = 1))]
created: i64,

updated: i64, // Field with no annotation is ignored

}

fn main() { let f = TestRust { keyone: String::from("one"), keytwo: String::from("two"), created: 0, updated: 0, };

println!("{}", f.create_table_cql()); /// CREATE TABLE IF NOT EXISTS fog.test_rust ( key_two TEXT,created TIMESTAMP,key_one UUID, PRIMARY KEY ((key_two,key_one), created) ) WITH CLUSTERING ORDER BY (created DESC) AND comment='From RUST'  AND  COMPACTION = { 'class' : 'SizeTieredCompactionStrategy' };
println!("{}", f.drop_table_cql());
println!("{}", f.key_space());
println!("{}", f.table_name());

}

```