serde: accept JSON numbers as Decimal in CLOB/data/gamma responses

Introduce a shared DecimalFromAny serde_with adapter in
src/serde_helpers.rs that accepts strings, integers, and floats when
deserializing rust_decimal::Decimal, and apply it to the response
fields where the Polymarket API returns JSON numbers rather than
strings.

Impact today: ClobClient::tick_size (called transitively by
limit_order().build() / market_order().build()) fails against the live
/tick-size endpoint because {"minimum_tick_size": 0.01} comes back as
a JSON number, so any live order placement errors out before signing.
data::Client::positions and gamma::Client::markets hit the same class
of bug on avgPrice, lastTradePrice, bestBid/bestAsk, volume fields,
liquidity fields, and price-change fields.

Covered structs:
- TickSize (clob): deserializer now goes through DecimalFromAny.
- Position, ClosedPosition, Trade (data): all Decimal fields annotated.
  ClosedPosition gains its missing #[serde_as] struct marker.
- Market and related (gamma): 56 Option<Decimal> fields annotated.

Backwards compatible: DecimalFromAny still accepts string-encoded
Decimals, so responses that already work continue to work. No new
dependencies. No feature flag changes.

Verified: cargo build / cargo test pass under
--features "clob,data,gamma,heartbeats,tracing" with no additional
failures introduced. Live reproduction of the pre-patch error:

    let client = ClobClient::new("https://clob.polymarket.com", ClobConfig::default())?;
    client.tick_size(some_real_token_id).await?;
    // Err: invalid type: floating point `0.01`, expected a Decimal type representing a fixed-point number

and after the patch the same call returns TickSize::Hundredth.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: moeuu

src/clob/types/mod.rs

@@ -417,7 +417,14 @@ impl<'de> Deserialize<'de> for TickSize {
     where
         D: Deserializer<'de>,
     {
-        let dec = <Decimal as Deserialize>::deserialize(deserializer)?;
+        // The Polymarket API returns `minimum_tick_size` as a JSON number
+        // (e.g. `0.01`), which `Decimal`'s default deserializer rejects
+        // because it expects a string. Delegate to the shared flexible
+        // Decimal deserializer so we handle both representations.
+        use serde_with::DeserializeAs;
+        let dec = <crate::serde_helpers::DecimalFromAny as DeserializeAs<Decimal>>::deserialize_as(
+            deserializer,
+        )?;
         TickSize::try_from(dec).map_err(de::Error::custom)
     }
 }

src/data/types/response.rs

@@ -7,6 +7,8 @@ use chrono::{DateTime, NaiveDate, Utc};
 use serde::{Deserialize, Deserializer};
 use serde_with::{DefaultOnNull, DisplayFromStr, NoneAsEmptyString, serde_as};
 
+use crate::serde_helpers::DecimalFromAny;
+
 use super::{ActivityType, Side};
 use crate::types::{Address, B256, Decimal, U256};
 
@@ -74,24 +76,34 @@ pub struct Position {
     /// The market condition ID (unique market identifier).
     pub condition_id: B256,
     /// Number of outcome tokens held.
+    #[serde_as(as = "DecimalFromAny")]
     pub size: Decimal,
     /// Average entry price for the position.
+    #[serde_as(as = "DecimalFromAny")]
     pub avg_price: Decimal,
     /// Initial value (cost basis) of the position.
+    #[serde_as(as = "DecimalFromAny")]
     pub initial_value: Decimal,
     /// Current market value of the position.
+    #[serde_as(as = "DecimalFromAny")]
     pub current_value: Decimal,
     /// Unrealized cash profit/loss.
+    #[serde_as(as = "DecimalFromAny")]
     pub cash_pnl: Decimal,
     /// Unrealized percentage profit/loss.
+    #[serde_as(as = "DecimalFromAny")]
     pub percent_pnl: Decimal,
     /// Total amount bought (cumulative).
+    #[serde_as(as = "DecimalFromAny")]
     pub total_bought: Decimal,
     /// Realized profit/loss from closed portions.
+    #[serde_as(as = "DecimalFromAny")]
     pub realized_pnl: Decimal,
     /// Realized percentage profit/loss.
+    #[serde_as(as = "DecimalFromAny")]
     pub percent_realized_pnl: Decimal,
     /// Current market price of the outcome.
+    #[serde_as(as = "DecimalFromAny")]
     pub cur_price: Decimal,
     /// Whether the position can be redeemed (market resolved).
     pub redeemable: bool,
@@ -129,6 +141,7 @@ pub struct Position {
 ///
 /// Returned by the `/closed-positions` endpoint. Represents positions that
 /// have been fully sold or redeemed, with final profit/loss figures.
+#[serde_as]
 #[derive(Debug, Clone, Deserialize, Builder)]
 #[serde(rename_all = "camelCase")]
 #[non_exhaustive]
@@ -140,12 +153,16 @@ pub struct ClosedPosition {
     /// The market condition ID (unique market identifier).
     pub condition_id: B256,
     /// Average entry price for the position.
+    #[serde_as(as = "DecimalFromAny")]
     pub avg_price: Decimal,
     /// Total amount bought (cumulative).
+    #[serde_as(as = "DecimalFromAny")]
     pub total_bought: Decimal,
     /// Realized profit/loss from the closed position.
+    #[serde_as(as = "DecimalFromAny")]
     pub realized_pnl: Decimal,
     /// Final market price when position was closed.
+    #[serde_as(as = "DecimalFromAny")]
     pub cur_price: Decimal,
     /// Unix timestamp when the position was closed.
     pub timestamp: i64,
@@ -187,8 +204,10 @@ pub struct Trade {
     /// The market condition ID (unique market identifier).
     pub condition_id: B256,
     /// Number of tokens traded.
+    #[serde_as(as = "DecimalFromAny")]
     pub size: Decimal,
     /// Execution price per token.
+    #[serde_as(as = "DecimalFromAny")]
     pub price: Decimal,
     /// Unix timestamp when the trade occurred.
     pub timestamp: i64,

src/gamma/types/response.rs

@@ -10,7 +10,7 @@ use serde_with::NoneAsEmptyString;
 use serde_with::json::JsonString;
 use serde_with::{DisplayFromStr, StringWithSeparator, formats::CommaSeparator, serde_as};
 
-use crate::serde_helpers::StringFromAny;
+use crate::serde_helpers::{DecimalFromAny, StringFromAny};
 use crate::types::{Address, B256, Decimal, U256};
 
 /// Image optimization metadata.
@@ -245,8 +245,11 @@ pub struct Event {
     pub new: Option<bool>,
     pub featured: Option<bool>,
     pub restricted: Option<bool>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub liquidity: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub open_interest: Option<Decimal>,
     pub sort_by: Option<String>,
     pub category: Option<String>,
@@ -260,10 +263,15 @@ pub struct Event {
     pub created_at: Option<DateTime<Utc>>,
     pub updated_at: Option<DateTime<Utc>>,
     pub comments_enabled: Option<bool>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub competitive: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_24hr: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1wk: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1mo: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1yr: Option<Decimal>,
     pub featured_image: Option<String>,
     pub disqus_thread: Option<String>,
@@ -274,7 +282,9 @@ pub struct Event {
     #[serde_as(as = "Option<StringFromAny>")]
     pub turn_provider_id: Option<String>,
     pub enable_order_book: Option<bool>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub liquidity_amm: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub liquidity_clob: Option<Decimal>,
     pub neg_risk: Option<bool>,
     #[serde_as(as = "NoneAsEmptyString")]
@@ -317,7 +327,9 @@ pub struct Event {
     pub cant_estimate: Option<bool>,
     pub estimated_value: Option<String>,
     pub templates: Option<Vec<Template>>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub spreads_main_line: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub totals_main_line: Option<Decimal>,
     pub carousel_map: Option<String>,
     pub pending_deployment: Option<bool>,
@@ -353,13 +365,15 @@ pub struct Market {
     pub end_date: Option<DateTime<Utc>>,
     pub category: Option<String>,
     pub amm_type: Option<String>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub liquidity: Option<Decimal>,
     pub sponsor_name: Option<String>,
     pub sponsor_image: Option<String>,
     pub start_date: Option<DateTime<Utc>>,
     pub x_axis_value: Option<String>,
     pub y_axis_value: Option<String>,
     pub denomination_token: Option<U256>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub fee: Option<Decimal>,
     pub image: Option<String>,
     pub icon: Option<String>,
@@ -370,6 +384,7 @@ pub struct Market {
     pub outcomes: Option<Vec<String>>,
     #[serde_as(as = "Option<JsonString>")]
     pub outcome_prices: Option<Vec<Decimal>>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume: Option<Decimal>,
     pub active: Option<bool>,
     pub market_type: Option<String>,
@@ -400,21 +415,29 @@ pub struct Market {
     pub question_id: Option<B256>,
     pub uma_end_date: Option<String>,
     pub enable_order_book: Option<bool>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub order_price_min_tick_size: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub order_min_size: Option<Decimal>,
     pub uma_resolution_status: Option<String>,
     pub curation_order: Option<i32>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_num: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub liquidity_num: Option<Decimal>,
     pub end_date_iso: Option<NaiveDate>,
     pub start_date_iso: Option<NaiveDate>,
     pub uma_end_date_iso: Option<NaiveDate>,
     pub has_reviewed_dates: Option<bool>,
     pub ready_for_cron: Option<bool>,
     pub comments_enabled: Option<bool>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_24hr: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1wk: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1mo: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1yr: Option<Decimal>,
     pub game_start_time: Option<String>,
     pub seconds_delay: Option<i32>,
@@ -427,19 +450,32 @@ pub struct Market {
     #[serde(rename = "teamBID")]
     pub team_b_id: Option<String>,
     pub uma_bond: Option<String>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub uma_reward: Option<Decimal>,
     pub fpmm_live: Option<bool>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_24hr_amm: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1wk_amm: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1mo_amm: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1yr_amm: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_24hr_clob: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1wk_clob: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1mo_clob: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_1yr_clob: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_amm: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_clob: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub liquidity_amm: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub liquidity_clob: Option<Decimal>,
     pub maker_base_fee: Option<i32>,
     pub taker_base_fee: Option<i32>,
@@ -460,18 +496,30 @@ pub struct Market {
     pub ready_timestamp: Option<DateTime<Utc>>,
     pub funded_timestamp: Option<DateTime<Utc>>,
     pub accepting_orders_timestamp: Option<DateTime<Utc>>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub competitive: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub rewards_min_size: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub rewards_max_spread: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub spread: Option<Decimal>,
     pub automatically_resolved: Option<bool>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub one_day_price_change: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub one_hour_price_change: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub one_week_price_change: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub one_month_price_change: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub one_year_price_change: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub last_trade_price: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub best_bid: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub best_ask: Option<Decimal>,
     pub automatically_active: Option<bool>,
     pub clear_book_on_start: Option<bool>,
@@ -484,6 +532,7 @@ pub struct Market {
     pub game_id: Option<String>,
     pub group_item_range: Option<String>,
     pub sports_market_type: Option<String>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub line: Option<Decimal>,
     pub uma_resolution_statuses: Option<String>,
     pub pending_deployment: Option<bool>,
@@ -532,11 +581,14 @@ pub struct ClobReward {
     pub condition_id: Option<B256>,
     pub start_date: Option<NaiveDate>,
     pub end_date: Option<NaiveDate>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub rewards_amount: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub rewards_daily_rate: Option<Decimal>,
 }
 
 /// A series of related events.
+#[serde_as]
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Builder)]
 #[serde(rename_all = "camelCase")]
 #[non_exhaustive]
@@ -566,9 +618,13 @@ pub struct Series {
     pub created_at: Option<DateTime<Utc>>,
     pub updated_at: Option<DateTime<Utc>>,
     pub comments_enabled: Option<bool>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub competitive: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume_24hr: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub volume: Option<Decimal>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub liquidity: Option<Decimal>,
     pub start_date: Option<DateTime<Utc>>,
     #[serde(rename = "pythTokenID")]
@@ -585,11 +641,13 @@ pub struct Series {
 }
 
 /// A comment position.
+#[serde_as]
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Builder)]
 #[serde(rename_all = "camelCase")]
 #[non_exhaustive]
 pub struct CommentPosition {
     pub token_id: Option<U256>,
+    #[serde_as(as = "Option<DecimalFromAny>")]
     pub position_size: Option<Decimal>,
 }