1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136

use std::fmt::Debug;

use implementations::{disk::Disk, memory::Memory};
pub use key::{Key, Scope, Segment};
use serde_json::Value;
use url::Url;

pub use crate::error::Error;
use crate::key::SegmentBuf;

mod error;
mod implementations;
mod key;

type Result<T, E = Error> = std::result::Result<T, E>;

pub trait ReadStore {
    fn has(&self, key: &Key) -> Result<bool>;
    fn has_scope(&self, scope: &Scope) -> Result<bool>;
    fn get(&self, key: &Key) -> Result<Option<Value>>;
    fn list_keys(&self, scope: &Scope) -> Result<Vec<Key>>;
    fn list_scopes(&self) -> Result<Vec<Scope>>;
}

pub trait WriteStore {
    fn store(&self, key: &Key, value: Value) -> Result<()>;
    fn move_value(&self, from: &Key, to: &Key) -> Result<()>;
    fn move_scope(&self, from: &Scope, to: &Scope) -> Result<()>;

    fn delete(&self, key: &Key) -> Result<()>;
    fn delete_scope(&self, scope: &Scope) -> Result<()>;
    fn clear(&self) -> Result<()>;
}

pub(crate) type TransactionCallback = Box<dyn Fn(&dyn KeyValueStoreBackend) -> Result<()>>;

pub trait KeyValueStoreBackend: ReadStore + WriteStore {
    fn transaction(&self, scope: &Scope, callback: TransactionCallback) -> Result<()>;
}

pub trait PubKeyValueStoreBackend: KeyValueStoreBackend + Debug + Send + Sync {}

impl<T> PubKeyValueStoreBackend for T where T: KeyValueStoreBackend + Debug + Send + Sync {}

#[derive(Debug)]
pub struct KeyValueStore {
    inner: Box<dyn PubKeyValueStoreBackend>,
}

impl KeyValueStore {
    pub fn new(storage_uri: &Url, namespace: impl Into<SegmentBuf>) -> Result<KeyValueStore> {
        let namespace = namespace.into();
        let inner: Box<dyn PubKeyValueStoreBackend> = match storage_uri.scheme() {
            "local" => {
                let path = format!(
                    "{}{}",
                    storage_uri.host_str().unwrap_or_default(),
                    storage_uri.path()
                );

                Box::new(Disk::new(&path, namespace.as_str())?)
            }
            "memory" => Box::new(Memory::new(
                format!(
                    "{} {}",
                    storage_uri.host_str().unwrap_or_default(),
                    namespace
                )
                .parse()
                .unwrap_or(namespace),
            )),
            #[cfg(feature = "postgres")]
            "postgres" => Box::new(crate::implementations::postgres::Postgres::new(
                storage_uri,
                namespace,
            )?),
            scheme => Err(crate::error::Error::UnknownScheme(scheme.to_owned()))?,
        };

        Ok(KeyValueStore { inner })
    }
}

impl KeyValueStoreBackend for KeyValueStore {
    fn transaction(&self, scope: &Scope, callback: TransactionCallback) -> Result<()> {
        self.inner.transaction(scope, callback)
    }
}

impl ReadStore for KeyValueStore {
    fn has(&self, key: &Key) -> Result<bool> {
        self.inner.has(key)
    }

    fn has_scope(&self, scope: &Scope) -> Result<bool> {
        self.inner.has_scope(scope)
    }

    fn get(&self, key: &Key) -> Result<Option<Value>> {
        self.inner.get(key)
    }

    fn list_keys(&self, scope: &Scope) -> Result<Vec<Key>> {
        self.inner.list_keys(scope)
    }

    fn list_scopes(&self) -> Result<Vec<Scope>> {
        self.inner.list_scopes()
    }
}

impl WriteStore for KeyValueStore {
    fn store(&self, key: &Key, value: Value) -> Result<()> {
        self.inner.store(key, value)
    }

    fn move_value(&self, from: &Key, to: &Key) -> Result<()> {
        self.inner.move_value(from, to)
    }

    fn move_scope(&self, from: &Scope, to: &Scope) -> Result<()> {
        self.inner.move_scope(from, to)
    }

    fn delete(&self, key: &Key) -> Result<()> {
        self.inner.delete(key)
    }

    fn delete_scope(&self, scope: &Scope) -> Result<()> {
        self.inner.delete_scope(scope)
    }

    fn clear(&self) -> Result<()> {
        self.inner.clear()
    }
}