cargo/ops/
cargo_config.rs

1//! Implementation of `cargo config` subcommand.
2
3use crate::util::context::{ConfigKey, ConfigValue as CV, Definition, GlobalContext};
4use crate::util::errors::CargoResult;
5use crate::{drop_eprintln, drop_println};
6use anyhow::{Error, bail, format_err};
7use serde_json::json;
8use std::borrow::Cow;
9use std::fmt;
10use std::str::FromStr;
11
12pub enum ConfigFormat {
13    Toml,
14    Json,
15    JsonValue,
16}
17
18impl ConfigFormat {
19    /// For clap.
20    pub const POSSIBLE_VALUES: [&'static str; 3] = ["toml", "json", "json-value"];
21}
22
23impl FromStr for ConfigFormat {
24    type Err = Error;
25    fn from_str(s: &str) -> CargoResult<Self> {
26        match s {
27            "toml" => Ok(ConfigFormat::Toml),
28            "json" => Ok(ConfigFormat::Json),
29            "json-value" => Ok(ConfigFormat::JsonValue),
30            f => bail!("unknown config format `{}`", f),
31        }
32    }
33}
34
35impl fmt::Display for ConfigFormat {
36    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
37        match *self {
38            ConfigFormat::Toml => write!(f, "toml"),
39            ConfigFormat::Json => write!(f, "json"),
40            ConfigFormat::JsonValue => write!(f, "json-value"),
41        }
42    }
43}
44
45/// Options for `cargo config get`.
46pub struct GetOptions<'a> {
47    pub key: Option<&'a str>,
48    pub format: ConfigFormat,
49    pub show_origin: bool,
50    pub merged: bool,
51}
52
53pub fn get(gctx: &GlobalContext, opts: &GetOptions<'_>) -> CargoResult<()> {
54    if opts.show_origin && !matches!(opts.format, ConfigFormat::Toml) {
55        bail!(
56            "the `{}` format does not support --show-origin, try the `toml` format instead",
57            opts.format
58        );
59    }
60    let key = match opts.key {
61        Some(key) => ConfigKey::from_str(key),
62        None => ConfigKey::new(),
63    };
64    if opts.merged {
65        let cv = gctx
66            .get_cv_with_env(&key)?
67            .ok_or_else(|| format_err!("config value `{}` is not set", key))?;
68        match opts.format {
69            ConfigFormat::Toml => print_toml(gctx, opts, &key, &cv),
70            ConfigFormat::Json => print_json(gctx, &key, &cv, true),
71            ConfigFormat::JsonValue => print_json(gctx, &key, &cv, false),
72        }
73        if let Some(env) = maybe_env(gctx, &key, &cv) {
74            match opts.format {
75                ConfigFormat::Toml => print_toml_env(gctx, &env),
76                ConfigFormat::Json | ConfigFormat::JsonValue => print_json_env(gctx, &env),
77            }
78        }
79    } else {
80        match &opts.format {
81            ConfigFormat::Toml => print_toml_unmerged(gctx, opts, &key)?,
82            format => bail!(
83                "the `{}` format does not support --merged=no, try the `toml` format instead",
84                format
85            ),
86        }
87    }
88    Ok(())
89}
90
91/// Checks for environment variables that might be used.
92fn maybe_env<'gctx>(
93    gctx: &'gctx GlobalContext,
94    key: &ConfigKey,
95    cv: &CV,
96) -> Option<Vec<(&'gctx str, &'gctx str)>> {
97    // Only fetching a table is unable to load env values. Leaf entries should
98    // work properly.
99    match cv {
100        CV::Table(_map, _def) => {}
101        _ => return None,
102    }
103    let mut env: Vec<_> = gctx
104        .env()
105        .filter(|(env_key, _val)| env_key.starts_with(&format!("{}_", key.as_env_key())))
106        .collect();
107    env.sort_by_key(|x| x.0);
108    if env.is_empty() { None } else { Some(env) }
109}
110
111fn print_toml(gctx: &GlobalContext, opts: &GetOptions<'_>, key: &ConfigKey, cv: &CV) {
112    let origin = |def: &Definition| -> String {
113        if !opts.show_origin {
114            return "".to_string();
115        }
116        format!(" # {}", def)
117    };
118    match cv {
119        CV::Boolean(val, def) => drop_println!(gctx, "{} = {}{}", key, val, origin(def)),
120        CV::Integer(val, def) => drop_println!(gctx, "{} = {}{}", key, val, origin(def)),
121        CV::String(val, def) => drop_println!(
122            gctx,
123            "{} = {}{}",
124            key,
125            toml_edit::Value::from(val),
126            origin(def)
127        ),
128        CV::List(vals, _def) => {
129            if opts.show_origin {
130                drop_println!(gctx, "{} = [", key);
131                for (val, def) in vals {
132                    drop_println!(
133                        gctx,
134                        "    {}, # {}",
135                        serde::Serialize::serialize(val, toml_edit::ser::ValueSerializer::new())
136                            .unwrap(),
137                        def
138                    );
139                }
140                drop_println!(gctx, "]");
141            } else {
142                let vals: toml_edit::Array = vals.iter().map(|x| &x.0).collect();
143                drop_println!(gctx, "{} = {}", key, vals);
144            }
145        }
146        CV::Table(table, _def) => {
147            let mut key_vals: Vec<_> = table.iter().collect();
148            key_vals.sort_by(|a, b| a.0.cmp(b.0));
149            for (table_key, val) in key_vals {
150                let mut subkey = key.clone();
151                // push or push_sensitive shouldn't matter here, since this is
152                // not dealing with environment variables.
153                subkey.push(table_key);
154                print_toml(gctx, opts, &subkey, val);
155            }
156        }
157    }
158}
159
160fn print_toml_env(gctx: &GlobalContext, env: &[(&str, &str)]) {
161    drop_println!(
162        gctx,
163        "# The following environment variables may affect the loaded values."
164    );
165    for (env_key, env_value) in env {
166        let val = shell_escape::escape(Cow::Borrowed(env_value));
167        drop_println!(gctx, "# {}={}", env_key, val);
168    }
169}
170
171fn print_json_env(gctx: &GlobalContext, env: &[(&str, &str)]) {
172    drop_eprintln!(
173        gctx,
174        "note: The following environment variables may affect the loaded values."
175    );
176    for (env_key, env_value) in env {
177        let val = shell_escape::escape(Cow::Borrowed(env_value));
178        drop_eprintln!(gctx, "{}={}", env_key, val);
179    }
180}
181
182fn print_json(gctx: &GlobalContext, key: &ConfigKey, cv: &CV, include_key: bool) {
183    let json_value = if key.is_root() || !include_key {
184        cv_to_json(cv)
185    } else {
186        let mut parts: Vec<_> = key.parts().collect();
187        let last_part = parts.pop().unwrap();
188        let mut root_table = json!({});
189        // Create a JSON object with nested keys up to the value being displayed.
190        let mut table = &mut root_table;
191        for part in parts {
192            table[part] = json!({});
193            table = table.get_mut(part).unwrap();
194        }
195        table[last_part] = cv_to_json(cv);
196        root_table
197    };
198    drop_println!(gctx, "{}", serde_json::to_string(&json_value).unwrap());
199
200    // Helper for recursively converting a CV to JSON.
201    fn cv_to_json(cv: &CV) -> serde_json::Value {
202        match cv {
203            CV::Boolean(val, _def) => json!(val),
204            CV::Integer(val, _def) => json!(val),
205            CV::String(val, _def) => json!(val),
206            CV::List(vals, _def) => {
207                let jvals: Vec<_> = vals.iter().map(|(val, _def)| json!(val)).collect();
208                json!(jvals)
209            }
210            CV::Table(map, _def) => {
211                let mut table = json!({});
212                for (key, val) in map {
213                    table[key] = cv_to_json(val);
214                }
215                table
216            }
217        }
218    }
219}
220
221fn print_toml_unmerged(
222    gctx: &GlobalContext,
223    opts: &GetOptions<'_>,
224    key: &ConfigKey,
225) -> CargoResult<()> {
226    let print_table = |cv: &CV| {
227        drop_println!(gctx, "# {}", cv.definition());
228        print_toml(gctx, opts, &ConfigKey::new(), cv);
229        drop_println!(gctx, "");
230    };
231    // This removes entries from the given CV so that all that remains is the
232    // given key. Returns false if no entries were found.
233    fn trim_cv(mut cv: &mut CV, key: &ConfigKey) -> CargoResult<bool> {
234        for (i, part) in key.parts().enumerate() {
235            match cv {
236                CV::Table(map, _def) => {
237                    map.retain(|key, _value| key == part);
238                    match map.get_mut(part) {
239                        Some(val) => cv = val,
240                        None => return Ok(false),
241                    }
242                }
243                _ => {
244                    let mut key_so_far = ConfigKey::new();
245                    for part in key.parts().take(i) {
246                        key_so_far.push(part);
247                    }
248                    bail!(
249                        "expected table for configuration key `{}`, \
250                         but found {} in {}",
251                        key_so_far,
252                        cv.desc(),
253                        cv.definition()
254                    )
255                }
256            }
257        }
258        Ok(match cv {
259            CV::Table(map, _def) => !map.is_empty(),
260            _ => true,
261        })
262    }
263
264    let mut cli_args = gctx.cli_args_as_table()?;
265    if trim_cv(&mut cli_args, key)? {
266        print_table(&cli_args);
267    }
268
269    // This slurps up some extra env vars that aren't technically part of the
270    // "config" (or are special-cased). I'm personally fine with just keeping
271    // them here, though it might be confusing. The vars I'm aware of:
272    //
273    // * CARGO
274    // * CARGO_HOME
275    // * CARGO_NAME
276    // * CARGO_EMAIL
277    // * CARGO_INCREMENTAL
278    // * CARGO_TARGET_DIR
279    // * CARGO_CACHE_RUSTC_INFO
280    //
281    // All of these except CARGO, CARGO_HOME, and CARGO_CACHE_RUSTC_INFO are
282    // actually part of the config, but they are special-cased in the code.
283    //
284    // TODO: It might be a good idea to teach the Config loader to support
285    // environment variable aliases so that these special cases are less
286    // special, and will just naturally get loaded as part of the config.
287    let mut env: Vec<_> = gctx
288        .env()
289        .filter(|(env_key, _val)| env_key.starts_with(key.as_env_key()))
290        .collect();
291    if !env.is_empty() {
292        env.sort_by_key(|x| x.0);
293        drop_println!(gctx, "# Environment variables");
294        for (key, value) in env {
295            // Displaying this in "shell" syntax instead of TOML, since that
296            // somehow makes more sense to me.
297            let val = shell_escape::escape(Cow::Borrowed(value));
298            drop_println!(gctx, "# {}={}", key, val);
299        }
300        drop_println!(gctx, "");
301    }
302
303    let unmerged = gctx.load_values_unmerged()?;
304    for mut cv in unmerged {
305        if trim_cv(&mut cv, key)? {
306            print_table(&cv);
307        }
308    }
309    Ok(())
310}
cargo/ops/cargo_config.rs

cargo/ops/
cargo_config.rs
