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1 | | -export function hi() {} |
| 1 | +import { |
| 2 | + types, |
| 3 | + getEnv, |
| 4 | + getParent, |
| 5 | + recordPatches, |
| 6 | + getPropertyMembers, |
| 7 | + isPrimitiveType, |
| 8 | + IAnyModelType |
| 9 | +} from "mobx-state-tree" |
| 10 | +import {observable, extendObservable, action} from "mobx" |
| 11 | + |
| 12 | +import {GraphQLClient} from "graphql-request" |
| 13 | +import {SubscriptionClient} from "subscriptions-transport-ws" |
| 14 | + |
| 15 | +export interface QueryOptions { |
| 16 | + raw?: boolean |
| 17 | + // TODO: headers |
| 18 | + // TODO: cacheStrategy |
| 19 | +} |
| 20 | + |
| 21 | +export type CaseHandlers<T, R> = { |
| 22 | + fetching(): R |
| 23 | + error(error: any): R |
| 24 | + data(data: T): R |
| 25 | +} |
| 26 | + |
| 27 | +export interface QueryResult<T = unknown> extends Promise<T> { |
| 28 | + fetching: boolean |
| 29 | + data: T | undefined |
| 30 | + error: any |
| 31 | + refetch(): Promise<T> |
| 32 | + case<R>(handlers: CaseHandlers<T, R>): R |
| 33 | +} |
| 34 | + |
| 35 | +export const MSTGQLStore = types.model("MSTGQLStore").actions(self => { |
| 36 | + const { |
| 37 | + gqlHttpClient, |
| 38 | + gqlWsClient |
| 39 | + }: {gqlHttpClient: GraphQLClient; gqlWsClient: SubscriptionClient} = getEnv( |
| 40 | + self |
| 41 | + ) |
| 42 | + if (!gqlHttpClient && !gqlWsClient) |
| 43 | + throw new Error( |
| 44 | + "Either gqlHttpClient or gqlWsClient (or both) should provided in the MSTGQLStore environment" |
| 45 | + ) |
| 46 | + |
| 47 | + function merge(data: unknown) { |
| 48 | + if (Array.isArray(data)) return data.map(item => mergeHelper(self, item)) |
| 49 | + else return mergeHelper(self, data) |
| 50 | + } |
| 51 | + |
| 52 | + function makeSingleRequest(query: string, variables: any): Promise<any> { |
| 53 | + if (gqlHttpClient) return gqlHttpClient.request(query, variables) |
| 54 | + else { |
| 55 | + return new Promise((resolve, reject) => { |
| 56 | + gqlWsClient |
| 57 | + .request({ |
| 58 | + query, |
| 59 | + variables |
| 60 | + }) |
| 61 | + .subscribe({ |
| 62 | + next(data) { |
| 63 | + resolve(data.data) |
| 64 | + }, |
| 65 | + error: reject |
| 66 | + }) |
| 67 | + }) |
| 68 | + } |
| 69 | + } |
| 70 | + |
| 71 | + function query<T>( |
| 72 | + query: string, |
| 73 | + variables?: any, |
| 74 | + options: QueryOptions = {} |
| 75 | + ): QueryResult<T> { |
| 76 | + // TODO: support options.headers |
| 77 | + // TODO: support options.cacheStrategy |
| 78 | + const req = makeSingleRequest(query, variables) |
| 79 | + |
| 80 | + const handleSuccess = action(data => { |
| 81 | + const value = getFirstValue(data) |
| 82 | + if (options.raw) { |
| 83 | + promise.fetching = false |
| 84 | + return Promise.resolve((promise.data = value)) |
| 85 | + } else { |
| 86 | + try { |
| 87 | + promise.fetching = false |
| 88 | + const normalized = (self as any).merge(value) |
| 89 | + return Promise.resolve((promise.data = normalized)) |
| 90 | + } catch (e) { |
| 91 | + return Promise.reject((promise.error = e)) |
| 92 | + } |
| 93 | + } |
| 94 | + }) |
| 95 | + |
| 96 | + const handleFailure = action(error => { |
| 97 | + promise.fetching = false |
| 98 | + return Promise.reject((promise.error = error)) |
| 99 | + }) |
| 100 | + |
| 101 | + const promise: QueryResult<T> = req.then( |
| 102 | + handleSuccess, |
| 103 | + handleFailure |
| 104 | + ) as any |
| 105 | + extendObservable( |
| 106 | + promise, |
| 107 | + { |
| 108 | + fetching: true, |
| 109 | + data: undefined, |
| 110 | + error: undefined, |
| 111 | + refetch() { |
| 112 | + // refech returs the old observable states |
| 113 | + promise.fetching = false |
| 114 | + return makeSingleRequest(query, variables).then( |
| 115 | + handleSuccess, |
| 116 | + handleFailure |
| 117 | + ) |
| 118 | + }, |
| 119 | + case<R>(handlers: CaseHandlers<T, R>): R { |
| 120 | + return promise.fetching && !promise.data |
| 121 | + ? handlers.fetching() |
| 122 | + : promise.error |
| 123 | + ? handlers.error(promise.error) |
| 124 | + : handlers.data(promise.data!) |
| 125 | + } |
| 126 | + } as any, |
| 127 | + {data: observable.ref} |
| 128 | + ) |
| 129 | + return promise |
| 130 | + } |
| 131 | + |
| 132 | + function mutate<T>( |
| 133 | + mutation: string, |
| 134 | + params?: any, |
| 135 | + optimisticUpdate?: () => void |
| 136 | + ): QueryResult<T> { |
| 137 | + if (optimisticUpdate) { |
| 138 | + const recorder = recordPatches(self) |
| 139 | + optimisticUpdate() |
| 140 | + recorder.stop() |
| 141 | + const promise = query<T>(mutation, params) |
| 142 | + promise.catch(e => { |
| 143 | + recorder.undo() |
| 144 | + }) |
| 145 | + return promise |
| 146 | + } else { |
| 147 | + return query(mutation, params) |
| 148 | + } |
| 149 | + } |
| 150 | + |
| 151 | + function subscribe(query: string, variables?: any): () => void { |
| 152 | + if (!gqlWsClient) throw new Error("No WS client available") |
| 153 | + const sub = gqlWsClient |
| 154 | + .request({ |
| 155 | + query, |
| 156 | + variables |
| 157 | + }) |
| 158 | + .subscribe({ |
| 159 | + next(data) { |
| 160 | + ;(self as any).merge(getFirstValue(data.data)) |
| 161 | + } |
| 162 | + }) |
| 163 | + return () => sub.unsubscribe() |
| 164 | + } |
| 165 | + |
| 166 | + return {merge, mutate, query, subscribe} |
| 167 | +}) |
| 168 | + |
| 169 | +export const MSTGQLObject = types |
| 170 | + .model("MSTGQLObject", { |
| 171 | + __typename: types.string, |
| 172 | + id: types.identifier |
| 173 | + }) |
| 174 | + .views(self => ({ |
| 175 | + get store(): typeof MSTGQLStore.Type { |
| 176 | + return getParent(self, 2) |
| 177 | + } |
| 178 | + })) |
| 179 | + |
| 180 | +export type HttpClientOptions = ConstructorParameters<typeof GraphQLClient>[1] |
| 181 | + |
| 182 | +export function createHttpClient(url: string, options: HttpClientOptions = {}) { |
| 183 | + return new GraphQLClient(url, options) |
| 184 | +} |
| 185 | + |
| 186 | +function typenameToCollectionName(typename: string) { |
| 187 | + return typename.toLowerCase() + "s" |
| 188 | +} |
| 189 | + |
| 190 | +function mergeHelper(store: any, itemData: any) { |
| 191 | + const {__typename, id} = itemData |
| 192 | + if (__typename === undefined) |
| 193 | + throw new Error( |
| 194 | + "__typename field is not available on " + JSON.stringify(itemData) |
| 195 | + ) |
| 196 | + if (id === undefined) |
| 197 | + throw new Error("id field is not available on " + JSON.stringify(itemData)) |
| 198 | + const collection = typenameToCollectionName(__typename) |
| 199 | + const current = store[collection].get(id) |
| 200 | + if (!current) { |
| 201 | + store[collection].set(id, itemData) |
| 202 | + return store[collection].get(id) |
| 203 | + } else { |
| 204 | + // TODO: merge should be recursive for complex values |
| 205 | + Object.assign(current, itemData) |
| 206 | + return current |
| 207 | + } |
| 208 | +} |
| 209 | + |
| 210 | +function getFirstValue(data: any) { |
| 211 | + const keys = Object.keys(data) |
| 212 | + if (keys.length !== 1) |
| 213 | + throw new Error( |
| 214 | + `Expected exactly one response key, got: ${keys.join(", ")}` |
| 215 | + ) |
| 216 | + return data[keys[0]] |
| 217 | +} |
| 218 | + |
| 219 | +export const coreFields = `\n__typename\nid\n` |
| 220 | + |
| 221 | +export function primitiveFields( |
| 222 | + mstType: IAnyModelType, |
| 223 | + exclude: string[] = [] |
| 224 | +) { |
| 225 | + const excludes = new Set(exclude) |
| 226 | + const primitives = new Set(["id", "__typename"]) |
| 227 | + const reflectionData = getPropertyMembers(mstType) |
| 228 | + for (const key in reflectionData.properties) |
| 229 | + if (!excludes.has(key)) { |
| 230 | + const type = reflectionData.properties[key] |
| 231 | + if (isPrimitiveType(type)) primitives.add(key) |
| 232 | + } |
| 233 | + return Array.from(primitives).join("\n") |
| 234 | +} |
| 235 | + |
| 236 | +// TODO: also have a utility for nested objects? |
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