code optimize

manifest.json

@@ -16,9 +16,10 @@
   },
   "background": {
     "scripts": [
+      "scripts/background.js",
+      "scripts/result.js",
       "scripts/tools.js",
-      "scripts/extract.js",
-      "scripts/background.js"
+      "scripts/extract.js"
     ],
     "persistent": false
   },
@@ -26,7 +27,6 @@
     "matches": ["*://*/*"],
     "js": [
       "scripts/jquery.min.js",
-      "scripts/tools.js",
       "scripts/content.js"
     ],
     "run_at": "document_idle"

scripts/background.js

@@ -1,9 +1,14 @@
 chrome.runtime.onMessage.addListener(function (message, sender, sendResponse) {
-    if (message.from === "DataExtracter:Extract")
+    if (message.from === "DataExtracter:Extract") {
+        if (!testArgs(...message.args)) {
+            sendResponse(signitures);
+            return;
+        }
         extract(...message.args).catch(
             err => {
                 console.log(err);
                 alert(err);
             }
         );
+    }
 });

scripts/content.js

@@ -1,19 +1,32 @@
-chrome.runtime.onMessage.addListener(
+function extract(...args) {
+    let message = {
+        from: "DataExtracter:Extract",
+        args: args
+    }
+    chrome.runtime.sendMessage(message, r => {
+        if (r) console.log(r);
+    });
+}
+
+chrome.runtime.onMessage.addListener(
     function (request, sender, sendResponse) {
+        if (!request.from) return;
+        let [ext, act] = request.from.split(":");
+        if (ext.toLowerCase() !== 'dataextracter') return;
         // console.log(request);
-        switch (request.from) {
-            case "DataExtracter:Extract":
-                let data = extractData(request.itemsSelector, request.fieldSelectors);
+        switch (act.toLowerCase()) {
+            case "extract":
+                let data = extractTabData(request.itemsSelector, request.fieldSelectors);
                 if (sendResponse) sendResponse(data);
                 break;
-            case "DataExtracter:GotoUrl":
+            case "gotourl":
                 window.location.replace(request.url);
                 if (sendResponse) sendResponse(request.url);
                 break;
-            case "DataExtracter:ReportIn":
+            case "reportin":
                 if (sendResponse) sendResponse(request.from);
                 break;
-            case "DataExtracter:QueryUrl":
+            case "queryurl":
                 if (sendResponse) sendResponse(window.location.href);
                 break;
             default:
@@ -22,7 +35,7 @@
     }
 );
 
-function extractData(itemsSelector, fieldSelectors) {
+function extractTabData(itemsSelector, fieldSelectors) {
     return $(itemsSelector).toArray().map(
         item => fieldSelectors.map(
             selector => {
@@ -31,65 +44,4 @@ function extractData(itemsSelector, fieldSelectors) {
             }
         )
     );
-}
-
-function extract(...args) {
-    let sig = `
-# DataExtracter Help
-----------------------------
-
-## Signitures:
-----------------------------
-
-function extract(itemsSelector:string, fieldSelectors:string[])
-function extract(itemsSelector:string, fieldSelectors:string[], url:string, from:number, to:number, interval:number)
-function extract(itemsSelector:string, fieldSelectors:string, url:string, pages:number[])
-
-## Examples:
-----------------------------
-
-### Extract current page
-extract(".list-item", ["a.title", "p.content"])
-
-### Extract multiple pages (1-10, interval 1)
-extract(".list-item", ["a.title", "p.content"],"http://sample.com/?pn=\${page}", 1, 10, 1)
-
-### Extract specified pages (1,3,5)
-extract(".list-item", ["a.title", "p.content"], "http://sample.com/?pn=\${page}", [1, 3, 5])
-
-## Advanced Examples:
-----------------------------
-
-### Extract link text and target (use 'selector@attribute')
-extract('.list-item', ['a.title', 'a.title@href'])
-`.trim();
-    if (!testArgs(...args)) {
-        console.log(sig);
-        return;
-    }
-    if (args.length == 2) {
-        saveFileAsk(extractData(args[0], args[1]));
-        return;
-    }
-    let message = {
-        from: "DataExtracter:Extract",
-        args: args
-    }
-    chrome.runtime.sendMessage(message, r => {
-        if (r) {
-            console.log(r);
-            alert(r);
-        }
-    });
-}
-
-function testArgs(...args) {
-    if (args.length < 2) return false;
-    if (args.length == 2)
-        return (args[0] && args[1] && (typeof args[0] == "string") && (args[1] instanceof Array))
-    let urls = [];
-    if (args.length > 2) return (typeof args[2] == "string") && (
-        (args[3] instanceof Array) ||
-        (!isNaN(args[3]) && !isNaN(args[4]) && !isNaN(args[5]))
-    )
 }

scripts/extract.js

@@ -2,54 +2,74 @@
  * Extract data from current tab / multiple urls.
  * @param {string} itemsSelector items selectors for selecting items (data rows)
  * @param {Array<string>} fieldSelectors fields selectors for selecting fields (data columns) under each item
- * @param {string} url url template to generate urls by filling with page numers.
- * @param {...number} args page numers, either [from, to, interval] or [...pages]
+ * @param {...any} args url list / url templates, page numers, either [from, to, interval] or [...pages]
  */
-function extract(itemsSelector, fieldSelectors, url, ...args) {
+async function extract(itemsSelector, fieldSelectors, ...args) {
+    let result = await getData(itemsSelector, fieldSelectors, ...args);
+    if (confirm(
+            `Click confirm to download if the sample data looks good (${result.data.length} items)：\n\n${result.toString(50) || "- Empty -"}`
+        )) {
+        saveFile(result, "text/csv");
+    }
+}
+
+/**
+ * Extract data from current tab / multiple urls.
+ * @param {string} itemsSelector items selectors for selecting items (data rows)
+ * @param {Array<string>} fieldSelectors fields selectors for selecting fields (data columns) under each item
+ * @param {...any} args url list / url templates, page numers, either [from, to, interval] or [...pages]
+ */
+async function getData(itemsSelector, fieldSelectors, ...args) {
+    if (!testArgs(itemsSelector, fieldSelectors, ...args))
+        throw new Error(`Invalid call arguments.\n\n${signitures}\n\n`);
     let urls = [];
-    if (url) {
-        if (args[0] instanceof Array) {
-            urls = args[0].map(p => url.replace("${page}", p));
-        } else if (args.length >= 3) {
-            let from = args.shift();
-            let to = args.shift();
-            let interval = args.shift();
-            for (let i = from; i <= to; i += interval) {
-                urls.push(url.replace("${page}", i));
+    if (args.length) {
+        let arg = args.shift();
+        if (arg instanceof Array) {
+            urls = arg;
+        } else if (arg instanceof ExractResult) {
+            urls = arg.column(0);
+        } else {
+            let urlTempl = arg;
+            if (urlTempl) {
+                if (args[0] instanceof Array) {
+                    urls = args[0].map(p => urlTempl.replace("${page}", p));
+                } else if (args.length >= 3) {
+                    let from = args.shift();
+                    let to = args.shift();
+                    let interval = args.shift();
+                    for (let i = from; i <= to; i += interval) {
+                        urls.push(urlTempl.replace("${page}", i));
+                    }
+                }
             }
         }
     }
     let data = [];
+    let tab = await getActiveTab(true) || await getActiveTab(false);
+    if (!tab) throw new Error("Cannot find active tab.");
     return new Promise((resolve, reject) => {
-        chrome.tabs.query({
-            active: true,
-            currentWindow: true
-        }, function (tabs) {
-            let pms;
-            let tab = tabs[0];
-            if (urls.length) {
-                pms = urls.reduce((p, url) => p.then(
-                    results => {
-                        data.push(...results);
-                        return redirectTab(tab, url).then(
-                            () => extractData(tab, itemsSelector, fieldSelectors)
-                        );
-                    },
-                    () => p
-                ), Promise.resolve([]));
-            } else {
-                pms = extractData(tab, itemsSelector, fieldSelectors);
-            }
-            pms.then(
+        let pms;
+        if (urls.length) {
+            pms = urls.reduce((p, url) => p.then(
                 results => {
                     data.push(...results);
-                    data.unshift(fieldSelectors);
-                    saveFileAsk(data);
-                    resolve("save done.")
+                    return redirectTab(tab, url).then(
+                        () => extractTabData(tab, itemsSelector, fieldSelectors)
+                    );
                 },
-                err => reject(err)
-            );
-        });
+                () => p
+            ), Promise.resolve([]));
+        } else {
+            pms = extractTabData(tab, itemsSelector, fieldSelectors);
+        }
+        pms.then(
+            results => {
+                data.push(...results);
+                resolve(new ExractResult(data));
+            },
+            err => reject(err)
+        );
     });
 }
 
@@ -60,10 +80,10 @@ function redirectTab(tab, url) {
             if (url !== u) {
                 curUrl = u;
                 let req = {
-                    from: "DataExtracter:GotoUrl",
+                    from: "GotoUrl",
                     url: url
                 }
-                chrome.tabs.sendMessage(tab.id, req);
+                sendMessage(tab, req);
             }
         })
         .then(() => queryUrl(tab, curUrl))
@@ -71,21 +91,20 @@ function redirectTab(tab, url) {
 }
 
 /**
- * extract data in from the target tab, usually used to detect if the content script is ready.
+ * extract data in from the target tab.
  * @param {any} tab target tab
  * @param {string} itemsSelector items selectors for selecting items (data rows)
  * @param {Array<string>} fieldSelectors fields selectors for selecting fields (data columns) under each item
  * @returns {Promise<string[]>} a promise of extracted data
  */
-function extractData(tab, itemsSelector, fieldSelectors) {
+function extractTabData(tab, itemsSelector, fieldSelectors) {
     let req = {
-        from: "DataExtracter:Extract",
+        from: "Extract",
         itemsSelector: itemsSelector,
         fieldSelectors: fieldSelectors
     }
-    let failMsg = "extractTabData failed after 10 second.";
     let cond = r => !!r;
-    return sendMessageAndDetect(tab, req, cond, failMsg);
+    return sendMessage(tab, req, cond);
 }
 
 /**
@@ -95,11 +114,10 @@ function extractData(tab, itemsSelector, fieldSelectors) {
  */
 function reportIn(tab) {
     let req = {
-        from: "DataExtracter:ReportIn"
+        from: "ReportIn"
     }
-    let failMsg = "reportIn failed after 10 second.";
     let cond = r => r == req.from;
-    return sendMessageAndDetect(tab, req, cond, failMsg);
+    return sendMessage(tab, req, cond);
 }
 
 /**
@@ -110,11 +128,10 @@ function reportIn(tab) {
  */
 function queryUrl(tab, urlExcluded) {
     let req = {
-        from: "DataExtracter:QueryUrl"
+        from: "QueryUrl"
     }
-    let failMsg = "queryUrl failed after 10 second.";
     let cond = url => url && (!urlExcluded || (urlExcluded && urlExcluded != url));
-    return sendMessageAndDetect(tab, req, cond, failMsg);
+    return sendMessage(tab, req, cond);
 }
 
 /**
@@ -122,27 +139,27 @@ function queryUrl(tab, urlExcluded) {
  * @param {object} tab the table where to send the message
  * @param {object} req the request data.
  * @param {function} cond success condition function, r:any=>boolean
- * @param {string} failMsg message when failed after time out
  * @param {number} failedTimeOut fail time out
  * @param {number} detectInterval interval for detecting
  * @return {Promise} a promise of the response.
  */
-function sendMessageAndDetect(tab, req, cond, failMsg, failedTimeOut, detectInterval) {
+function sendMessage(tab, req, cond, failedTimeOut, detectInterval) {
+    req.from = "DataExtracter:" + req.from;
     failedTimeOut = failedTimeOut || 10000;
     detectInterval = detectInterval || 500;
     return new Promise((resolve, reject) => {
         let timeOut;
         let rejectTimeout = setTimeout(() => {
-            reject(failMsg);
+            reject(`${req.from} failed after ${failedTimeOut/1000} seconds.`);
             clearTimeout(timeOut);
         }, failedTimeOut);
         loop();
 
         function loop() {
             chrome.tabs.sendMessage(tab.id, req, r => {
-                if (cond(r)) {
-                    resolve(r);
+                if (!cond || cond(r)) {
                     clearTimeout(rejectTimeout);
+                    resolve(r);
                 } else {
                     timeOut = setTimeout(() => {
                         loop();
@@ -151,4 +168,15 @@ function sendMessageAndDetect(tab, req, cond, failMsg, failedTimeOut, detectInte
             });
         }
     });
+}
+
+async function getActiveTab(currentWindow) {
+    return new Promise((resolve, reject) => {
+        chrome.tabs.query({
+            active: true,
+            currentWindow: currentWindow
+        }, function (tabs) {
+            resolve(tabs[0]);
+        })
+    })
 }

scripts/result.js

@@ -0,0 +1,31 @@
+class ExractResult {
+    constructor(data) {
+        this._data = data || [];
+
+    }
+    row(index) {
+        return this._data[index];
+    }
+    column(index) {
+        return [...new Array(this._data.length).keys()].map(
+            i => this._data[i][index]
+        );
+    }
+    get data() {
+        return this._data;
+    }
+    toString(rowsCount) {
+        let data = rowsCount > 0 ? this._data.slice(0, rowsCount) : this._data;
+        return data.slice().reduce(
+            (csv, lineCells) => {
+                let line = lineCells.reduce(
+                    (lineText, cell, idx) => {
+                        cell = '"' + cell.trim().replace(/"/g, '""') + '"';
+                        return lineText + cell + (idx == lineCells.length - 1 ? "" : ",")
+                    }, "");
+                return csv + line + "\n";
+            },
+            ""
+        );
+    }
+}

scripts/tools.js

@@ -1,16 +1,43 @@
-function formatCSV(data) {
-    return data.reduce(
-        (csv, lineCells) => {
-            let line = lineCells.reduce(
-                (lineText, cell, idx) => {
-                    cell = '"' + cell.trim().replace(/"/g, '""') + '"';
-                    return lineText + cell + (idx == lineCells.length - 1 ? "" : ",")
-                }, "");
-            return csv + line + "\n";
-        },
-        ""
-    );
-}
+const signitures = `
+# DataExtracter Help
+----------------------------
+
+## Signitures:
+----------------------------
+
+function extract(itemsSelector:string, fieldSelectors:string[])
+function extract(itemsSelector:string, fieldSelectors:string[], url:string, from:number, to:number, interval:number)
+function extract(itemsSelector:string, fieldSelectors:string, url:string, pages:number[])
+function extract(itemsSelector:string, fieldSelectors:string[], urls:string[])
+function extract(itemsSelector:string, fieldSelectors:string[], urls:ExractResult)
+
+## Examples:
+----------------------------
+
+### Extract current page
+extract(".list-item", ["a.title", "p.content"])
+
+### Extract multiple pages (1-10, interval 1)
+extract(".list-item", ["a.title", "p.content"],"http://sample.com/?pn=\${page}", 1, 10, 1)
+
+### Extract multiple urls (list)
+extract(".list-item", ["a.title", "p.content"],["http://sample.com/abc","http://sample.com/xyz"])
+
+### Extract specified pages (1,3,5)
+extract(".list-item", ["a.title", "p.content"], "http://sample.com/?pn=\${page}", [1, 3, 5])
+
+## Advanced Examples:
+----------------------------
+
+### Extract link text and target (use 'selector@attribute')
+extract('.list-item', ['a.title', 'a.title@href'])
+
+### Collect links from page(s) & Extract data of each link
+>> (Available only in console of extension background page)
+
+extract('body',["a.title", "p.content"], await getData('.list-item', ['.item a@href'],["http://sample.com/abc"]))
+`.trim();
+
 
 function saveFile(data, mimeType, fileName) {
     fileName = fileName || document.title || "result";
@@ -44,10 +71,48 @@ function saveFile(data, mimeType, fileName) {
     }
 }
 
-function saveFileAsk(data) {
-    let csv = formatCSV(data.slice(1, 50)).trim() || "- Empty -";
-    if (confirm(`Click confirm to download if the sample data looks good (${data.length-1} items)：\n\n${csv}`)) {
-        csv = formatCSV(data);
-        saveFile(csv, "text/csv");
+function testArgs(...args) {
+    switch (args.length) {
+        case 0, 1:
+            return false;
+        case 2:
+            return args[0] && args[1] &&
+                (typeof args[0] == "string") &&
+                (args[1] instanceof Array) &&
+                testArrayVals(args[1], v => typeof v == "string");
+        case 3:
+            return args[0] && args[1] &&
+                typeof args[0] == "string" &&
+                args[1] instanceof Array &&
+                testArrayVals(args[1], v => typeof v == "string") &&
+                (
+                    (
+                        args[2] instanceof Array &&
+                        testArrayVals(args[2], v => typeof v == "string")
+                    ) || (
+                        args[2] instanceof ExractResult
+                    )
+                );
+        case 4:
+            return args[0] && args[1] &&
+                typeof args[0] == "string" &&
+                args[1] instanceof Array &&
+                testArrayVals(args[1], v => typeof v == "string") &&
+                typeof args[2] == "string" &&
+                args[3] instanceof Array &&
+                testArrayVals(args[3], v => typeof v == "number");
+        case 6:
+            return args[0] && args[1] &&
+                typeof args[0] == "string" &&
+                args[1] instanceof Array &&
+                testArrayVals(args[1], v => typeof v == "string") &&
+                typeof args[2] == "string" &&
+                !isNaN(args[3]) && !isNaN(args[4]) && !isNaN(args[5]);
+        default:
+            return false;
+    }
+
+    function testArrayVals(arr, tester) {
+        return arr.reduce((p, c) => p && tester(c), true);
     }
 }